Sample records for t-cell depleted haploidentical

  1. Novel treatment of severe combined immunodeficiency utilizing ex-vivo T-cell depleted haploidentical hematopoietic stem cell transplantation and CD45RA+ depleted donor lymphocyte infusions.

    PubMed

    Brodszki, Nicholas; Turkiewicz, Dominik; Toporski, Jacek; Truedsson, Lennart; Dykes, Josefina

    2016-01-15

    Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment available for severe combined immunodeficiency (SCID); although, there is a high incidence of severe infections and an increased risk of graft-versus host-disease (GvHD) with HSCT. Early intervention is a crucial prognostic factor and a HLA-haploidentical parental donor is often available. Haploidentical HSCT protocols utilizing extensively ex vivo T-cell depleted grafts (CliniMACs system) have proven efficient in preventing GvHD, but cause a delay in early T-cell recovery that increases the risk of viral infections. Here, we present a novel approach for treating SCID that combines selective depletion of GvHD-inducing alpha/beta (α/β) T-cells from the haploidentical HSCT graft with a subsequent donor lymphocyte infusion (DLI) enriched for CD45RO+ memory T-cells. Our patient was diagnosed with SCID (T-B + NK+ phenotype). At 9 months of age, he received a T cell receptor(TCR)α/β-cell depleted graft from his haploidentical mother, following a reduced intensity conditioning regimen with no additional GvHD prophylaxis. Engraftment was rapid with complete donor chimerism and no signs of GvHD. However, at 12 weeks post HSCT, the patient was still T-cell lymphopenic with clinical symptoms of multiple severe viral infections. Consequently, therapeutic DLIs were initiated for enhanced anti-viral immunity. The patient was treated with CD45RA+ depleted haploidentical maternal donor lymphocytes enriched from unmobilized whole blood, and a total T-cell dose of no more than 25 x10(3) CD3+ cells/kg with >99.9% purity of CD3 + CD45RO+ memory T-cells was transferred. Following the DLI, a prompt increase in CD3 + CD4+ and CD3 + CD8+ counts was observed with a subsequent clearance of viral infections. No acute or chronic GvHD was observed. Automated depletion of CD45RA+ naïve T-cells from unmobilized whole blood is a simple and rapid strategy to provide unmanipulated DLIs

  2. Differences in Aspergillus-specific immune recovery between T-cell-replete and T-cell-depleted hematopoietic transplants.

    PubMed

    Perruccio, Katia; Topini, Fabiana; Tosti, Antonella; Gazzola, Maria Vittoria; Messina, Chiara; Martelli, Massimo F; Caniglia, Maurizio; Velardi, Andrea; Cesaro, Simone

    2015-12-01

    After hematopoietic stem cell transplantation, invasive aspergillosis remains one of the most lethal infections. Susceptibility may be due to prophylaxis and treatment of graft-vs.-host disease in T-cell-replete transplants, and delayed immune rebuilding due to T-cell depletion in haploidentical transplantation. We monitored CD4(+) T-cell recovery and anti-Aspergillus immune competence in pediatric recipients of T-cell-replete matched transplants and of prevalently adult recipients of T-cell-depleted matched or haploidentical transplants for hematological malignancies. Although CD4(+) T-cell counts were higher in T-cell-replete transplant recipients at all post-transplant time points, Aspergillus-specific T cells were first detected 15-18 months after T-cell-replete matched, 7-9 months after T-cell-depleted matched, and 9-12 months after haploidentical transplantation, respectively. Incidence of invasive aspergillosis was 22% with 10% mortality after T-cell-replete transplants, 0% after T-cell-depleted matched, and 7% with 4% mortality after haploidentical transplants. Although T-cell counts were significantly higher after T-cell-replete transplants, post-transplant immune suppression/GvHD appeared to impair their function. Specific Aspergillus immune competence recovered faster after T-cell-depleted transplants, whether matched or haploidentical. T-cell-replete transplants were associated with a higher incidence of invasive aspergillosis and Aspergillus-related deaths. These results showed that T-cell depletion without post-transplant immunosuppression is associated to a faster immune recovery than T-cell-replete transplantation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Selective Depletion of αβ T Cells and B Cells for Human Leukocyte Antigen-Haploidentical Hematopoietic Stem Cell Transplantation. A Three-Year Follow-Up of Procedure Efficiency.

    PubMed

    Li Pira, Giuseppina; Malaspina, David; Girolami, Elia; Biagini, Simone; Cicchetti, Elisabetta; Conflitti, Gianpiero; Broglia, Manuel; Ceccarelli, Stefano; Lazzaro, Stefania; Pagliara, Daria; Meschini, Antonella; Bertaina, Alice; Montanari, Mauro; Locatelli, Franco

    2016-11-01

    HLA-haploidentical family donors represent a valuable option for children requiring allogeneic hematopoietic stem cell transplantation (HSCT). Because graft-versus-host diseases (GVHD) is a major complication of HLA-haploidentical HSCT because of alloreactive T cells in the graft, different methods have been used for ex vivo T cell depletion. Removal of donor αβ T cells, the subset responsible for GVHD, and of B cells, responsible for post-transplantation lymphoproliferative disorders, have been recently developed for HLA-haploidentical HSCT. This manipulation preserves, in addition to CD34 +  progenitors, natural killer, γδ T, and monocytes/dendritic cells, contributing to anti-leukemia activity and protection against infections. We analyzed depletion efficiency and cell yield in 200 procedures performed in the last 3 years at our center. Donors underwent CD34 +   hematopoietic stem cell (HSC) peripheral blood mobilization with granulocyte colony-stimulating factor (G-CSF). Poor CD34 +  cell mobilizers (48 of 189, 25%) received plerixafor in addition to G-CSF. Aphereses containing a median of 52.5 × 10 9 nucleated cells and 494 × 10 6 CD34 +  HSC were manipulated using the CliniMACS device. In comparison to the initial product, αβ T cell depletion produced a median 4.1-log reduction (range, 3.1 to 5.5) and B cell depletion led to a median 3.4-log reduction (range, 2.0 to 4.7). Graft products contained a median of 18.5 × 10 6 CD34 +  HSC/kg recipient body weight, with median values of residual αβ T cells and B cells of 29 × 10 3 /kg and 33 × 10 3 /kg, respectively. Depletion efficiency monitored at 6-month intervals demonstrated steady performance, while improved recovery of CD34 +  cells was observed after the first year (P = .0005). These data indicate that αβ T cell and B cell depletion of HSC grafts from HLA-haploidentical donors was efficient and reproducible. Copyright © 2016 The American Society for Blood and Marrow

  4. Adoptive immunotherapy with allodepleted donor T-cells improves immune reconstitution after haploidentical stem cell transplantation

    PubMed Central

    Amrolia, Persis J.; Muccioli-Casadei, Giada; Huls, Helen; Adams, Stuart; Durett, April; Gee, Adrian; Yvon, Eric; Weiss, Heidi; Cobbold, Mark; Gaspar, H. Bobby; Rooney, Cliona; Kuehnle, Ingrid; Ghetie, Victor; Schindler, John; Krance, Robert; Heslop, Helen E.; Veys, Paul; Vitetta, Ellen; Brenner, Malcolm K.

    2006-01-01

    Poor T lymphocyte reconstitution limits the use of haploidentical stem cell transplantation (SCT) because it results in a high mortality from viral infections. One approach to overcome this problem is to infuse donor T cells from which alloreactive lymphocytes have been selectively depleted, but the immunologic benefit of this approach is unknown. We have used an anti-CD25 immunotoxin to deplete alloreactive lymphocytes and have compared immune reconstitution after allodepleted donor T cells were infused at 2 dose levels into recipients of T-cell–depleted haploidentical SCT. Eight patients were treated at 104 cells/kg/dose, and 8 patients received 105 cells/kg/dose. Patients receiving 105 cells/kg/dose showed significantly improved T-cell recovery at 3, 4, and 5 months after SCT compared with those receiving 104 cells/kg/dose (P < .05). Accelerated T-cell recovery occurred as a result of expansion of the effector memory (CD45RA–CCR-7-) population (P < .05), suggesting that protective T-cell responses are likely to be long lived. T-cell–receptor signal joint excision circles (TRECs) were not detected in reconstituting T cells in dose-level 2 patients, indicating they are likely to be derived from the infused allodepleted cells. Spectratyping of the T cells at 4 months demonstrated a polyclonal Vβ repertoire. Using tetramer and enzyme-linked immunospot (ELISPOT) assays, we have observed cytomegalovirus (CMV)– and Epstein-Barr virus (EBV)–specific responses in 4 of 6 evaluable patients at dose level 2 as early as 2 to 4 months after transplantation, whereas such responses were not observed until 6 to 12 months in dose-level 1 patients. The incidence of significant acute (2 of 16) and chronic graft-versus-host disease (GVHD; 2 of 15) was low. These data demonstrate that allodepleted donor T cells can be safely used to improve T-cell recovery after haploidentical SCT and may broaden the applicability of this approach. PMID:16741253

  5. Haploidentical/mismatched hematopoietic stem cell transplantation without in vitro T cell depletion for T cell acute lymphoblastic leukemia.

    PubMed

    Wang, Yu; Liu, Dai-Hong; Xu, Lan-Ping; Liu, Kai-Yan; Chen, Huan; Chen, Yu-Hong; Han, Wei; Zhang, Xiao-Hui; Huang, Xiao-Jun

    2012-05-01

    The outcome of T cell acute lymphoblastic leukemia (T-ALL) is poorly understood. Allogeneic hematopoietic stem cell transplantation (HSCT) remains 1 of the best options to cure T-ALL. However, many patients cannot find an HLA-matched donor. Our institute established a new protocol for haplo-identical HSCT. Busulfan, cyclophosphamide, cytosine arabinoside, and methyl CCNU plus antithymocyte globulin was used for conditioning therapy. Seventy-two patients diagnosed with T-ALL underwent transplantation from haploidentical donor family members. The incidence rates of grades II to IV acute graft-versus-host disease (aGVHD) and of grades III and IV aGVHD were 49% ± 12% and 19% ± 12%, respectively. The cumulative incidence rate for chronic GVHD (cGVHD) at 2 years after HSCT was 41% ± 12%. After a median follow-up of 12 months, 15 patients had relapsed, 14 died from relapse, and 41 patients were still alive without disease recurrence. The probability of leukemia-free survival (LFS) was 44.2% ± 7.4% at 3 years. Patients transplanted during their first complete remission (CR1) had a lower relapse rate (18.8% versus 37.5%, P = .049, with a relative risk [RR] = 0.247, P = .007), a lower nonrelapse mortality (NRM) rate (16.6% versus 50.0%, P = .046, with an RR = 0.279, P = .024), and better LFS (54.8% versus 12.5%, P = .001, with an RR = 0.315, P = .004) compared with patients transplanted beyond CR1. This study confirmed that haploidentical/mismatched HSCT could be an alternative treatment choice for T-ALL. Copyright © 2012 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  6. Haploidentical HCT using an αβ T-cell-depleted graft with targeted αβ(+) cells by add-back after a reduced intensity preparative regimen containing low-dose TBI.

    PubMed

    Im, H J; Koh, K N; Suh, J K; Lee, S W; Choi, E S; Jang, S; Kwon, S W; Park, C-J; Seo, J J

    2016-09-01

    Between 2012 and 2015, 42 pediatric patients underwent haploidentical hematopoietic cell transplantation using an αβ(+) T-cell-depleted graft with targeted αβ cells at 1-5 × 10(5)/kg by add-back; 31 had hematologic malignancy (HM), 8 had non-malignant disease (NM) and 3 had solid tumors. All patients received uniform reduced-intensity conditioning with fludarabine, cyclophosphamide, rabbit anti-thymocyte globulin and low-dose TBI. All 42 patients achieved neutrophil engraftment at a median of 10 days. The cumulative incidences (CIs) of ⩾grade II and ⩾grade III acute GvHD were 31±7.1% (SE) and 12±5.0%, respectively, and 1-year CI of chronic GvHD was 15±5.8%. One patient died of CMV pneumonia, leading to transplant-related mortality (TRM) of 2.6±2.5%. Sixteen patients relapsed and 11 died of disease. At a median follow-up of 19 months (range, 5-43 months), the estimated 2-year event-free survival for NM and HM were 88±11.7 and 50±10.1%, respectively. Our study demonstrated that haploidentical hematopoietic cell transplantation after ex vivo depletion of αβ(+) T cells with targeted dose noticeably reduced the graft failure rate and TRM in pediatric patients and could be applied to patients lacking a suitable related or unrelated donor.

  7. Selective T-cell depletion targeting CD45RA reduces viremia and enhances early T-cell recovery compared with CD3-targeted T-cell depletion.

    PubMed

    Triplett, Brandon M; Muller, Brad; Kang, Guolian; Li, Ying; Cross, Shane J; Moen, Joseph; Cunningham, Lea; Janssen, William; Mamcarz, Ewelina; Shook, David R; Srinivasan, Ashok; Choi, John; Hayden, Randall T; Leung, Wing

    2018-02-01

    T-cell depletion (TCD) effectively reduces severe graft-versus-host disease in recipients of HLA-mismatched allografts. However, TCD is associated with delayed immune recovery and increased infections. We hypothesized that specific depletion of CD45RA+ naive T cells, rather than broad depletion of CD3+ T cells, can preserve memory-immunity in the allografts and confer protection against important viral infections in the early post-transplant period. Sixty-seven patients who received TCD haploidentical donor transplantation for hematologic malignancy on 3 consecutive trials were analyzed. Patients receiving CD45RA-depleted donor grafts had 2000-fold more donor T cells infused, significantly higher T-cell counts at Day +30 post transplant (550/μL vs 10/μL; P < .001), and higher T-cell diversity by Vbeta spectratyping at Day +100 (P < .001). Importantly, these recipients experienced a significant reduction in both the incidence (P = .002) and duration (P = .02) of any viremia (cytomegalovirus, Epstein-Barr virus, or adenovirus) in the first 6 months post transplant. Specifically, recipients of CD3-depleted grafts were more likely to experience adenovirus viremia (27% vs 4%, P = .02). CD45RA-depletion provided a large number of donor memory T cells to the recipients and was associated with enhanced early T-cell recovery and protection against viremia. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Outcome of children with acute leukemia given HLA-haploidentical HSCT after αβ T-cell and B-cell depletion.

    PubMed

    Locatelli, Franco; Merli, Pietro; Pagliara, Daria; Li Pira, Giuseppina; Falco, Michela; Pende, Daniela; Rondelli, Roberto; Lucarelli, Barbarella; Brescia, Letizia Pomponia; Masetti, Riccardo; Milano, Giuseppe Maria; Bertaina, Valentina; Algeri, Mattia; Pinto, Rita Maria; Strocchio, Luisa; Meazza, Raffaella; Grapulin, Lavinia; Handgretinger, Rupert; Moretta, Alessandro; Bertaina, Alice; Moretta, Lorenzo

    2017-08-03

    Allogeneic hematopoietic stem cell transplantation (HSCT) from an HLA-haploidentical relative (haplo-HSCT) is a suitable option for children with acute leukemia (AL) either relapsed or at high-risk of treatment failure. We developed a novel method of graft manipulation based on negative depletion of αβ T and B cells and conducted a prospective trial evaluating the outcome of children with AL transplanted with this approach. Eighty AL children, transplanted between September 2011 and September 2014, were enrolled in the trial. All children were given a fully myeloablative preparative regimen. Anti-T-lymphocyte globulin from day -5 to -3 was used for preventing graft rejection and graft-versus-host disease (GVHD); no patient received any posttransplantation GVHD prophylaxis. Two children experienced primary graft failure. The cumulative incidence of skin-only, grade 1-2 acute GVHD was 30%; no patient developed extensive chronic GVHD. Four patients died, the cumulative incidence of nonrelapse mortality being 5%, whereas 19 relapsed, resulting in a 24% cumulative incidence of relapse. With a median follow-up of 46 months for surviving patients, the 5-year probability of chronic GVHD-free, relapse-free survival (GRFS) is 71%. Total body irradiation-containing preparative regimen was the only variable favorably influencing relapse incidence and GRFS. The outcomes of these 80 patients are comparable to those of 41 and 51 children given transplantation from an HLA-identical sibling or a 10/10 allelic-matched unrelated donor in the same period. These data indicate that haplo-HSCT after αβ T- and B-cell depletion represents a competitive alternative for children with AL in need of urgent allograft. This trial was registered at www.clinicaltrials.gov as #NCT01810120. © 2017 by The American Society of Hematology.

  9. Selective T cell-depleted haploidentical hematopoietic stem cell transplantation for relapsed/refractory neuroblastoma.

    PubMed

    Liu, Anthony P Y; Lee, Pamela P W; Kwok, Janette S Y; Leung, Rock Y Y; Chiang, Alan K S; Ha, Shau-Yin; Cheuk, Daniel K L; Chan, Godfrey C F

    2018-06-19

    Relapsed/refractory NB carries a bleak outcome, warranting novel treatment options. HaploHSCT induces a graft-versus-NB effect via natural killer cell alloreactivity. Review of patients with relapsed/refractory NB who underwent haploHSCT with ex vivo T-cell depletion in our unit from 2013 through 2018. Ten patients were identified (male=5; median age at haploHSCT=6.45 y, range: 3.49-11.02 y). Indications were relapsed in 7 and refractoriness in 3; disease status at haploHSCT was CR in 2, PR in 6, and PD in 2. All patients received peripheral blood stem cell grafts after ex vivo T-cell depletion (CD3/CD19-depletion=1; TCR-αβ/CD19-depletion=4; CD3/CD45RA-depletion=4; and TCR-αβ/CD45RA-depletion=1). Conditioning regimens were fludarabine-based. Neutrophils engrafted on median D + 10 (range: D + 9 to +13), and platelets engrafted (≥20 × 10 9 /L) on median D + 8 (range: D + 5 to D + 14). Early T- and NK-cell recovery were evident. Of the 10 patients, acute rejection developed in 1 (who died of PD despite rescue HSCT), and 1 died of sepsis before engraftment; 8 experienced full donor-chimerism post-HSCT. Among the 8, 6 experienced CR, 1 died of PD, and 1 died of pulmonary hypertensive crisis before evaluation. At publication, 4 were in remission (2.8, 7.4, 28.5, and 58.9 months). No significant GvHD occurred. HaploHSCT with selective ex vivo T-cell depletion may be a safe and useful salvage strategy for relapsed/refractory NB. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Related HLA-mismatched/haploidentical hematopoietic stem cell transplantation without in vitro T-cell depletion: observations of a single Chinese center.

    PubMed

    Huang, Xiaojun; Liu, Daihong

    2011-01-01

    The Institute of Hematology, Peking University, is the largest hematopoietic stem cell transplantation (HSCT) center in China. A total of 400 HSCTs performed in 2010 accounted for a quarter of all allogeneic HSCTs performed in China. The GIAC protocol, which uses HLA-mismatched/haploidentical blood or bone marrow transplantation without in vitro T-cell depletion, entails administration of granulocyte-colony stimulating factor (G-CSF) to all donors, intensified immunological suppression, and treatment with anti-human thymocyte immunoglobulin. The stem cell grafts are a combination of G-CSF-primed bone marrow cells and G-CSF-mobilized peripheral blood stem cells, which may be critical to the success of this protocol through the immune modulation of G-CSF. Using this protocol, more than 99% engraftment and complete donor chimerism were achieved in pediatric and adult patients with hematological malignancies. The incidence of graft-versus-host disease (GVHD) grades 3 and 4 was 13.4% and that of extensive chronic GVHD 22.6%. Comparable relapse rates were observed between patients who received unmanipulated haploidentical transplantation, and those who received HLA-identical or unrelated HSCT. Patients with confirmed minimal residual disease, (expression levels of Wilms' tumor suppressor gene 1 and flow cytometry) after HSCT received pre-emptive modified donor lymphocyte infusion to prevent relapse. Infection was the main cause of non-relapse death. Prospective studies are ongoing to investigate the mechanisms of immune reconstitution in order to refine the protocol. In 1964, a patient with severe aplastic anemia received a bone marrow infusion from her syngeneic, pregnant sister, and remained disease-free over a 40-year follow-up period. Following this success, there was a 20-year interruption in the transplantation program at our center. The hiatus ended in 1981 with the first allogeneic HSCT, which was used to treat a girl with acute lymphoblastic leukemia (ALL). In

  11. Successful adoptive transfer and in vivo expansion of haploidentical γδ T cells.

    PubMed

    Wilhelm, Martin; Smetak, Manfred; Schaefer-Eckart, Kerstin; Kimmel, Brigitte; Birkmann, Josef; Einsele, Hermann; Kunzmann, Volker

    2014-02-15

    The primary aim of this pilot study was to determine the feasibility and safety of an adoptive transfer and in vivo expansion of human haploidentical γδ T lymphocytes. Patients with advanced haematological malignancies who are not eligible for allogeneic transplantation received peripheral blood mononuclear cells from half-matched family donors. For that, a single unstimulated leukapheresis product was incubated with both the anti-CD4 and anti-CD8 antibodies conjugated to paramagnetic particles. The depletion procedure was performed on a fully automated CliniMACS device according to the manufacturer's instructions. On average, patients received 2.17 × 10⁶/kg (range 0.9-3.48) γδ T cells with <1% CD4- or CD8-positive cells remaining in the product. All patients received prior lymphopenia-inducing chemotherapy (fludarabine 20-25 mg/m² day -6 until day -2 and cyclophosphamide 30-60 mg/kg day -6 and -5) and were treated with 4 mg zoledronate on day 0 and 1.0 x 10⁶ IU/m² IL-2 on day +1 until day +6 for the induction of γδ T cell proliferation in vivo. This resulted in a marked in vivo expansion of donor γδ T cells and, to a lower extent, natural killer cells and double-negative αβ T cells (mean 68-fold, eight-fold, and eight-fold, respectively). Proliferation peaked by around day +8 and donor cells persisted up to 28 days. Although refractory to all prior therapies, three out of four patients achieved a complete remission, which lasted for 8 months in a patient with plasma cell leukaemia. One patient died from an infection 6 weeks after treatment. This pilot study shows that adoptive transfer and in vivo expansion of haploidentical γδ T lymphocytes is feasible and suggests a potential role of these cells in the treatment of haematological diseases.

  12. T-cell replete haploidentical donor transplantation using post-transplant CY: an emerging standard-of-care option for patients who lack an HLA-identical sibling donor.

    PubMed

    Bashey, A; Solomon, S R

    2014-08-01

    Availability of an HLA-identical sibling (MRD) or suitably matched unrelated donor (MUD) has historically been a limiting factor in the application of allogeneic hematopoietic transplantation. Although almost all patients have an HLA-haploidentical family donor, prior attempts at transplantation from such donors using T-cell replete grafts and conventional immunosuppression were associated with unacceptable rates of GVHD, and when stringent ex vivo T-cell depletion was used to control GVHD, rates of graft rejection and post-transplant infections were prohibitive. The recent approach to HLA-haploidentical donor transplantation developed in Baltimore that uses T-cell replete grafts and post-transplant CY (Haplo-post-HCT-CY) to control post-transplant allo-reactivity appears to have overcome many of the obstacles historically associated with haploidentical donor transplantation. In particular, TRM rates of <10% are usual and rapid reconstitution of immunity leads to a low rate of post-transplant infections and no post-tranplant lymphoproliferative disorders (PTLD), consistent with the hypothesis that post-transplant CY selectively depletes proliferating alloreactive T cells responsible for GVHD and graft rejection while preserving resting memory T cells essential for post-transplant immunologic recovery. In parallel trials using similar non-myeloablative conditioning regimens, Haplo-post-HCT-CY produced similar overall survival to double umbilical cord blood transplantation(DUCBT) in adult patients (62% vs 54%), with low rates of TRM (7% vs 24%), severe acute GVHD (0% vs 21%) and chronic GVHD (13% vs 25%). Furthermore, recent non-randomized comparisons adjusted for risk factors show that Haplo-post-HCT-CY achieve at least equivalent outcomes to conventional MRD and MUD transplants. Although most experience has been obtained using BM, emerging data suggest that a G-CSF mobilized PBSC graft can also safely be used for Haplo-post-HCT-CY. Haplo-post-HCT-CY also avoids the

  13. Optimization of individualized graft composition: CD3/CD19 depletion combined with CD34 selection for haploidentical transplantation.

    PubMed

    Huenecke, Sabine; Bremm, Melanie; Cappel, Claudia; Esser, Ruth; Quaiser, Andrea; Bonig, Halvard; Jarisch, Andrea; Soerensen, Jan; Klingebiel, Thomas; Bader, Peter; Koehl, Ulrike

    2016-09-01

    Excessive T-cell depletion (TCD) is a prerequisite for graft manufacturing in haploidentical stem cell (SC) transplantation by using either CD34 selection or direct TCD such as CD3/CD19 depletion. To optimize graft composition we compared 1) direct or indirect TCD only, 2) a combination of CD3/CD19-depleted with CD34-selected grafts, or 3) TCD twice for depletion improvement based on our 10-year experience with 320 separations in graft manufacturing and quality control. SC recovery was significantly higher (85%, n = 187 vs. 73%, n = 115; p < 0.0001), but TCD was inferior (median log depletion, -3.6 vs. -5.2) for CD3/CD19 depletion compared to CD34 selection, respectively. For end products with less than -2.5 log TCD, a second depletion step led to a successful improvement in TCD. Thawing of grafts showed a high viability and recovery of SCs, but low NK-cell yield. To optimize individualized graft engineering, a calculator was developed to estimate the results of the final graft based on the content of CD34+ and CD3+ cells in the leukapheresis product. Finally, calculated splitting of the starting product followed by CD3/19 depletion together with CD34+ graft manipulation may enable the composition of optimized grafts with high CD34+-cell and minimal T-cell content. © 2016 AABB.

  14. Effective adoptive transfer of haploidentical tumor-specific T cells in B16-melanoma bearing mice.

    PubMed

    Cui, Nai-peng; Xie, Shao-jian; Han, Jin-sheng; Ma, Zhen-feng; Chen, Bao-ping; Cai, Jian-hui

    2012-03-01

    Adoptive transfer of allogeneic tumor-specific T cells often results in severe graft-versus-host disease (GVHD). Here, we sought to maximize graft-versus-tumor and minimize GVHD by using haploidentical T cells in pre-irradiated B16-melanoma bearing mice. C57BL/6 mice bearing B16-melanoma tumors were irradiated with 0, 5, or 7 Gy total body irradiation (TBI), or 7 Gy TBI plus bone marrow transplantation. Tumor areas were measured every 3 days to assess the influence of irradiation treatment on tumor regression. B16-melanoma bearing mice were irradiated with 7 Gy TBI; sera and spleens were harvested at days 1, 3, 5, 7, 9, 11, and 13 after irradiation. White blood cell levels were measured and transforming growth factor β1 (TGF-b1) and interleukin 10 (IL-10) levels in serum were detected using enzyme-linked immunosorbent assay (ELISA) kits. Real-time reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometry were performed to test TGF-b1, IL-10 and Foxp3 mRNA levels and the proportion of CD4+CD25+Foxp3+ T-regulatory cells (Tregs) in spleens. B16-melanoma bearing C57BL/6 mice were irradiated with 7 Gy TBI followed by syngeneic (Syn1/Syn2) or haploidentical (Hap1/Hap2), dendritic cell-induced cytotoxic T lymphocytes (DC-CTLs) treatment, tumor areas and system GVHD were observed every 3 days. Mice were killed 21 days after the DC-CTLs adoptive transfer; histologic analyses of eyes, skin, liver, lungs, and intestine were then performed. Irradiation with 7 Gy TBI on the B16-melanoma-bearing mice did not influence tumor regression compared to the control group; however, it down-regulated the proportion of Tregs in spleens and the TGF-b1 and IL-10 levels in sera and spleens, suggesting inhibition of autoimmunity and intervention of tumor microenvironment. Adoptive transfer of haploidentical DC-CTLs significantly inhibited B16-melanoma growth. GVHD assessment and histology analysis showed no significant difference among the groups. Adoptive transfer of

  15. Is there a stronger graft-versus-leukemia effect using HLA-haploidentical donors compared with HLA-identical siblings?

    PubMed

    Ringdén, O; Labopin, M; Ciceri, F; Velardi, A; Bacigalupo, A; Arcese, W; Ghavamzadeh, A; Hamladji, R M; Schmid, C; Nagler, A; Mohty, M

    2016-02-01

    Haploidentical hematopoietic stem cell transplants (HSCTs) are increasingly used, but it is unknown whether they have a stronger graft-versus-leukemia (GVL) effect. We analyzed 10 679 acute leukemia patients who underwent HSCT from an HLA-matched sibling donor (MSD, n=9815) or a haploidentical donor (⩾2 HLA-antigen disparity, n=864) between 2007 and 2012, reported to the European Group for Blood and Marrow Transplantation. In a Cox regression model, acute and chronic graft-versus-host disease (GVHD) was added as time-dependent variables. There was no difference in probability of relapse between recipients of haploidentical and MSD grafts. Factors of importance for relapse after T-cell-replete grafts included remission status at HSCT, Karnofsky score ⩽80, acute GVHD of grade II or higher and chronic GVHD (P<10(-5)). Patients with post-transplant cyclophosphamide (n=194) had similar outcome as other T-cell-replete haploidentical transplants (n=369). Non-relapse mortality was significantly higher in the haploidentical group compared with that in MSD patients (P<10(-5)). Leukemia-free survival was superior in the MSD patients receiving T-cell-replete (P<10(-5)) or T-cell-depleted grafts (P=0.0006). The risk of relapse was the same in acute leukemia patients who received haploidentical donor grafts as in those given MSD transplants, suggesting a similar GVL effect.

  16. Immunological Outcome in Haploidentical-HSC Transplanted Patients Treated with IL-10-Anergized Donor T Cells

    PubMed Central

    Bacchetta, Rosa; Lucarelli, Barbarella; Sartirana, Claudia; Gregori, Silvia; Lupo Stanghellini, Maria T.; Miqueu, Patrick; Tomiuk, Stefan; Hernandez-Fuentes, Maria; Gianolini, Monica E.; Greco, Raffaella; Bernardi, Massimo; Zappone, Elisabetta; Rossini, Silvano; Janssen, Uwe; Ambrosi, Alessandro; Salomoni, Monica; Peccatori, Jacopo; Ciceri, Fabio; Roncarolo, Maria-Grazia

    2013-01-01

    T-cell therapy after hematopoietic stem cell transplantation (HSCT) has been used alone or in combination with immunosuppression to cure hematologic malignancies and to prevent disease recurrence. Here, we describe the outcome of patients with high-risk/advanced stage hematologic malignancies, who received T-cell depleted (TCD) haploidentical-HSCT (haplo-HSCT) combined with donor T lymphocytes pretreated with IL-10 (ALT-TEN trial). IL-10-anergized donor T cells (IL-10-DLI) contained T regulatory type 1 (Tr1) cells specific for the host alloantigens, limiting donor-vs.-host-reactivity, and memory T cells able to respond to pathogens. IL-10-DLI were infused in 12 patients with the goal of improving immune reconstitution after haplo-HSCT without increasing the risk of graft-versus-host-disease (GvHD). IL-10-DLI led to fast immune reconstitution in five patients. In four out of the five patients, total T-cell counts, TCR-Vβ repertoire and T-cell functions progressively normalized after IL-10-DLI. These four patients are alive, in complete disease remission and immunosuppression-free at 7.2 years (median follow-up) after haplo-HSCT. Transient GvHD was observed in the immune reconstituted (IR) patients, despite persistent host-specific hypo-responsiveness of donor T cells in vitro and enrichment of cells with Tr1-specific biomarkers in vivo. Gene-expression profiles of IR patients showed a common signature of tolerance. This study provides the first indication of the feasibility of Tr1 cell-based therapy and paves way for the use of these Tr1 cells as adjuvant treatment for malignancies and immune-mediated disorders. PMID:24550909

  17. Haploidentical and Matched Sibling Donor Hematopoietic Cell Transplantation for Patients with HLA-Homozygous Haplotypes.

    PubMed

    Kanda, Junya; Ikegame, Kazuhiro; Fuji, Shigeo; Kurokawa, Mineo; Kanamori, Heiwa; Fukuda, Takahiro; Ohashi, Kazuteru; Ishikawa, Jun; Ogawa, Hiroyasu; Inoue, Masami; Ichinohe, Tatsuo; Atsuta, Yoshiko; Kanda, Yoshinobu

    2016-11-01

    More than 1% of the Japanese population has HLA-homozygous haplotypes. For patients with such haplotypes, HLA-haploidentical family members who have no HLA mismatch in the graft-versus-host direction are readily available donor candidates for hematopoietic cell transplantation (HCT). In this study, the outcomes of patients with homozygous HLA-A, -B, and -DRB1 antigens who received HCT without T cell depletion from a haploidentical related donor with mismatches in the host-versus-graft direction only (hetero-to-homo, n = 78) or from an HLA-matched sibling donor (MSD) (MSD-homo, n = 153) were compared with those in patients with heterozygous haplotypes who received HCT from an MSD (MSD-hetero, n = 7242). Transplant outcomes in the hetero-to-homo group were similar to those in the MSD-hetero group regarding neutrophil engraftment, grades III to IV acute graft-versus-host disease (aGVHD), nonrelapse mortality (NRM), relapse, and overall survival. On the other hand, the incidences of severe aGVHD and NRM in the MSD-homo group were significantly lower than those in the MSD-hetero group (grades III to IV aGVHD: aHR .50, P = .034; NRM: aHR .48, P = .004). In conclusion, patients with HLA-homozygous haplotypes achieved lower GVHD and NRM rates for MSD transplantation than those with HLA-heterozygous haplotypes. When an MSD or an appropriate alternative donor is not available for patients with HLA-homozygous haplotypes who need immediate transplantation, transplantation from a haploidentical donor without T cell depletion is a viable option, given the comparable transplant outcomes for hetero-to-homo HCT and MSD-hetero HCT. Copyright © 2016 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  18. Haploidentical Stem Cell Transplantation for Refractory/Relapsed Neuroblastoma.

    PubMed

    Illhardt, Toni; Toporski, Jacek; Feuchtinger, Tobias; Turkiewicz, Dominik; Teltschik, Heiko-Manuel; Ebinger, Martin; Schwarze, Carl-Philipp; Holzer, Ursula; Lode, Holger N; Albert, Michael H; Gruhn, Bernd; Urban, Christian; Dykes, Josefina H; Teuffel, Oliver; Schumm, Michael; Handgretinger, Rupert; Lang, Peter

    2018-05-01

    Pediatric patients with refractory or relapsed metastatic neuroblastoma (NBL) have a poor prognosis despite autologous stem cell transplantation (SCT). Allogeneic SCT from a haploidentical donor has a remarkable alloreactive effect in patients with leukemia; thus, we evaluated this approach in children with very high-risk NBL. We analyzed data from 2 prospective phase I/II trials. A total of 26 patients with refractory (n = 5), metastatic relapsed (n = 20), or locally relapsed MYCN-positive (n = 1) NBL received a median of 17 × 10 6 /kg T/B cell-depleted CD34 + stem cells with 68 × 10 3 /kg residual T cells and 107 × 10 6 /kg natural killer cells. The conditioning regimen comprised melphalan, fludarabine, thiotepa, OKT3, and a short course of mycophenolate mofetil post-transplantation. Engraftment occurred in 96% of the patients. Event-free survival and overall survival at 5 years were 19% and 23%, respectively. No transplantation-related mortality was observed, and the single death was due to progression/subsequent relapse. The median duration of follow-up was 8.1 years. Patients in complete remission before SCT had a significantly better prognosis than those with residual tumor load (P < .01). All patients with progressive disease before SCT relapsed within 1 year. Grade II and grade III acute graft-versus-host disease (GVHD) occurred in 31% and 12% of the patients, respectively. Chronic limited and extensive GVHD occurred in 28% and 10%, respectively. Our data indicate that haploidentical SCT is a feasible treatment option that can induce long-term remission in some patients with NBL with tolerable side effects, and may enable the development of further post-transplantation therapeutic strategies based on the donor-derived immune system. Copyright © 2018. Published by Elsevier Inc.

  19. Clinical-grade purification of natural killer cells in haploidentical hematopoietic stem cell transplantation.

    PubMed

    Meyer-Monard, Sandrine; Passweg, Jakob; Siegler, Uwe; Kalberer, Christian; Koehl, Ulrike; Rovó, Alicia; Halter, Jörg; Stern, Martin; Heim, Dominik; Alois Gratwohl, Johannes Rischewski; Tichelli, André

    2009-02-01

    Because of a high risk of graft-versus-host disease (GVHD), donor lymphocyte infusions with unmodified lymphapheresis products are not used after haploidentical hematopoietic stem cell transplantation. Natural killer (NK) cells have antitumor activity and may consolidate engraftment without inducing GVHD. Production of NK cells under good manufacturing practice (GMP) conditions in a sufficient number is difficult. Twenty-four apheresis procedures and subsequent NK-cell enrichment from 14 haploidentical donors were performed. NK-cell enrichment was performed using a GMP suitable immunomagnetic procedure. Factors influencing the NK-cell recovery, purity, and NK-cell dose were analyzed. A median number of 4.9 x 10(8) NK cells were obtained and median NK-cell recovery was 58 percent. Median T-cell depletion was 4.32 log. The absolute NK-cell number in the final product after processing significantly correlated with the preharvest NK-cell content of the peripheral blood (p = 0.002, r = 0.867). The NK-cell recovery was inversely correlated to the absolute NK-cell number in the apheresis product (p = 0.01, r = -0.51). The NK-cell dose per kg of body weight of the patient was inversely correlated to the weight of the patient (p = 0.007, r = -0.533). Donors with a high NK-cell count in peripheral blood are likely to provide NK-cell products with the highest cell number. However, maximal NK-cell dose is limited and high NK-cell doses may only be obtained for patients with a low body weight, making children and young adults the best candidates for NK-cell therapy.

  20. Co-infusion of haplo-identical CD19-chimeric antigen receptor T cells and stem cells achieved full donor engraftment in refractory acute lymphoblastic leukemia.

    PubMed

    Cai, Bo; Guo, Mei; Wang, Yao; Zhang, Yajing; Yang, Jun; Guo, Yelei; Dai, Hanren; Yu, Changlin; Sun, Qiyun; Qiao, Jianhui; Hu, Kaixun; Zuo, Hongli; Dong, Zheng; Zhang, Zechuan; Feng, Mingxing; Li, Bingxia; Sun, Yujing; Liu, Tieqiang; Liu, Zhiqing; Wang, Yi; Huang, Yajing; Yao, Bo; Han, Weidong; Ai, Huisheng

    2016-11-25

    Elderly patients with relapsed and refractory acute lymphoblastic leukemia (ALL) have poor prognosis. Autologous CD19 chimeric antigen receptor-modified T (CAR-T) cells have potentials to cure patients with B cell ALL; however, safety and efficacy of allogeneic CD19 CAR-T cells are still undetermined. We treated a 71-year-old female with relapsed and refractory ALL who received co-infusion of haplo-identical donor-derived CD19-directed CAR-T cells and mobilized peripheral blood stem cells (PBSC) following induction chemotherapy. Undetectable minimal residual disease by flow cytometry was achieved, and full donor cell engraftment was established. The transient release of cytokines and mild fever were detected. Significantly elevated serum lactate dehydrogenase, alanine transaminase, bilirubin and glutamic-oxalacetic transaminase were observed from days 14 to 18, all of which were reversible after immunosuppressive therapy. Our preliminary results suggest that co-infusion of haplo-identical donor-derived CAR-T cells and mobilized PBSCs may induce full donor engraftment in relapsed and refractory ALL including elderly patients, but complications related to donor cell infusions should still be cautioned. Allogeneic CART-19 for Elderly Relapsed/Refractory CD19+ ALL. NCT02799550.

  1. T-cell-replete haploidentical HSCT with low-dose anti-T-lymphocyte globulin compared with matched sibling HSCT and unrelated HSCT.

    PubMed

    Luo, Yi; Xiao, Haowen; Lai, Xiaoyu; Shi, Jimin; Tan, Yamin; He, Jingsong; Xie, Wanzhuo; Zheng, Weiyan; Zhu, Yuanyuan; Ye, Xiujin; Yu, Xiaohong; Cai, Zhen; Lin, Maofang; Huang, He

    2014-10-23

    We developed an approach of T-cell-replete haploidentical hematopoietic stem cell transplantation (HSCT) with low-dose anti-T-lymphocyte globulin and prospectively compared outcomes of all contemporaneous T-cell-replete HSCT performed at our center using matched sibling donors (MSDs), unrelated donors (URDs), and haploidentical related donors (HRDs). From 2008 to 2013, 90 patients underwent MSD-HSCT, 116 underwent URD-HSCT, and 99 underwent HRD-HSCT. HRDs were associated with higher incidences of grades 2 to 4 (42.4%) and severe acute graft-versus-host disease (17.2%) and nonrelapse mortality (30.5%), compared with MSDs (15.6%, 5.6%, and 4.7%, respectively; P < .05), but were similar to URDs, even fully 10/10 HLA-matched URDs. For high-risk patients, a superior graft-versus-leukemia effect was observed in HRD-HSCT, with 5-year relapse rates of 15.4% in HRD-HSCT, 28.2% in URD-HSCT (P = .07), and 49.9% in MSD-HSCT (P = .002). Furthermore, 5-year disease-free survival rates were not significantly different for patients undergoing transplantation using 3 types of donors, with 63.6%, 58.4%, and 58.3% for MSD, URD, and HRD transplantation, respectively (P = .574). Our data indicate that outcomes after HSCT from suitably matched URDs and HRDs with low-dose anti-T-lymphocyte globulin are similar and that HRD improves outcomes of patients with high-risk leukemia. This trial was registered at www.chictr.org (Chinese Clinical Trial Registry) as #ChiCTR-OCH-12002490. © 2014 by The American Society of Hematology.

  2. Successful haploidentical donor hematopoietic stem cell transplant and restoration of STAT3 function in an adolescent with autosomal dominant hyper-IgE syndrome.

    PubMed

    Patel, N C; Gallagher, J L; Torgerson, T R; Gilman, A L

    2015-07-01

    Autosomal dominant hyper-IgE syndrome (AD-HIES), caused by mutations in Signal Transducer and Activator of Transcription 3 (STAT3) is associated with defective STAT3 signaling and Th17 differentiation and recurrent bacterial and fungal infections. Most patients suffer significant morbidity and premature mortality. Hematopoietic stem cell transplantation (HSCT) has been reported in a small number of cases, with mixed outcomes. We report successful haploidentical donor HSCT in a patient with AD-HIES. Evaluation of lymphocyte subsets, STAT3 signaling, and Th17 cells was performed pre- and post-HSCT. A 14-year old female with AD-HIES developed recurrent methicillin-resistant Staphylococcus aureus (MRSA) abscesses. Immunologic analysis showed elevated IgE (4331 kU/L), absent Th17 cells, and markedly decreased STAT3 phosphorylation in cytokine stimulated peripheral blood mononuclear cells. She had breakthrough abscesses despite clindamycin and trimethoprim-sulfamethoxazole prophylaxis, and developed steroid refractory autoimmune hemolytic anemia. She underwent T-cell depleted haploidentical HSCT from her father following reduced intensity conditioning. She developed one MRSA hand abscess after transplant. Twenty-four months post transplant, she had complete donor chimerism (>95 % donor), normal absolute T cell numbers, and a normal percentage of Th17 cells. IgE was normal at 25 kU/L. She remains well 42 months after transplantation off all antibacterial prophylaxis. Haploidentical HSCT led to successful bone marrow engraftment, normalization of STAT3 signaling in hematopoietic cells, normalization of IgE, and restoration of immune function in this patient with AD-HIES.

  3. Preservation of Antigen-Specific Functions of αβ T Cells and B Cells Removed from Hematopoietic Stem Cell Transplants Suggests Their Use As an Alternative Cell Source for Advanced Manipulation and Adoptive Immunotherapy.

    PubMed

    Li Pira, Giuseppina; Di Cecca, Stefano; Biagini, Simone; Girolami, Elia; Cicchetti, Elisabetta; Bertaina, Valentina; Quintarelli, Concetta; Caruana, Ignazio; Lucarelli, Barbarella; Merli, Pietro; Pagliara, Daria; Brescia, Letizia Pomponia; Bertaina, Alice; Montanari, Mauro; Locatelli, Franco

    2017-01-01

    Hematopoietic stem cell transplantation is standard therapy for numerous hematological diseases. The use of haploidentical donors, sharing half of the HLA alleles with the recipient, has facilitated the use of this procedure as patients can rely on availability of a haploidentical donor within their family. Since HLA disparity increases the risk of graft-versus-host disease, T-cell depletion has been used to remove alloreactive lymphocytes from the graft. Selective removal of αβ T cells, which encompass the alloreactive repertoire, combined with removal of B cells to prevent EBV-related lymphoproliferative disease, proved safe and effective in clinical studies. Depleted αβ T cells and B cells are generally discarded as by-products. Considering the possible use of donor T cells for donor lymphocyte infusions or for generation of pathogen-specific T cells as mediators of graft-versus-infection effect, we tested whether cells in the discarded fractions were functionally intact. Response to alloantigens and to viral antigens comparable to that of unmanipulated cells indicated a functional integrity of αβ T cells, in spite of the manipulation used for their depletion. Furthermore, B cells proved to be efficient antigen-presenting cells, indicating that antigen uptake, processing, and presentation were fully preserved. Therefore, we propose that separated αβ T lymphocytes could be employed for obtaining pathogen-specific T cells, applying available methods for positive selection, which eventually leads to indirect allodepletion. In addition, these functional T cells could undergo additional manipulation, such as direct allodepletion or genetic modification.

  4. Preservation of Antigen-Specific Functions of αβ T Cells and B Cells Removed from Hematopoietic Stem Cell Transplants Suggests Their Use As an Alternative Cell Source for Advanced Manipulation and Adoptive Immunotherapy

    PubMed Central

    Li Pira, Giuseppina; Di Cecca, Stefano; Biagini, Simone; Girolami, Elia; Cicchetti, Elisabetta; Bertaina, Valentina; Quintarelli, Concetta; Caruana, Ignazio; Lucarelli, Barbarella; Merli, Pietro; Pagliara, Daria; Brescia, Letizia Pomponia; Bertaina, Alice; Montanari, Mauro; Locatelli, Franco

    2017-01-01

    Hematopoietic stem cell transplantation is standard therapy for numerous hematological diseases. The use of haploidentical donors, sharing half of the HLA alleles with the recipient, has facilitated the use of this procedure as patients can rely on availability of a haploidentical donor within their family. Since HLA disparity increases the risk of graft-versus-host disease, T-cell depletion has been used to remove alloreactive lymphocytes from the graft. Selective removal of αβ T cells, which encompass the alloreactive repertoire, combined with removal of B cells to prevent EBV-related lymphoproliferative disease, proved safe and effective in clinical studies. Depleted αβ T cells and B cells are generally discarded as by-products. Considering the possible use of donor T cells for donor lymphocyte infusions or for generation of pathogen-specific T cells as mediators of graft-versus-infection effect, we tested whether cells in the discarded fractions were functionally intact. Response to alloantigens and to viral antigens comparable to that of unmanipulated cells indicated a functional integrity of αβ T cells, in spite of the manipulation used for their depletion. Furthermore, B cells proved to be efficient antigen-presenting cells, indicating that antigen uptake, processing, and presentation were fully preserved. Therefore, we propose that separated αβ T lymphocytes could be employed for obtaining pathogen-specific T cells, applying available methods for positive selection, which eventually leads to indirect allodepletion. In addition, these functional T cells could undergo additional manipulation, such as direct allodepletion or genetic modification. PMID:28386262

  5. T-cell-depleted haploidentical stem cell transplantation results improve with time in adults with acute leukemia: A study from the Acute Leukemia Working Party of the European Society of Blood and Marrow Transplantation (EBMT).

    PubMed

    Sestili, Simona; Labopin, Myriam; Ruggeri, Annalisa; Velardi, Andrea; Ciceri, Fabio; Maertens, Johan; Kanz, Lothar; Aversa, Franco; Lewalle, Philippe; Bunjes, Donald; Mohty, Mohamad; Nagler, Arnon

    2018-05-15

    T-cell-depleted, haploidentical transplantations (haplos) are commonly offered to patients who have high-risk, acute leukemia in the absence of a human leukocyte antigen (HLA) full-matched donor. To determine the effect of transplantation period, the authors divided 308 adults with de novo, acute leukemia who underwent T-cell-depleted haplo from 2005 to 2015 into 2 groups, according the year in which they underwent transplantation (2005-2011 [n = 191] and 2012-2015 [n = 117]). The median age was 41 years in patients who underwent transplantation before 2012 and 46 years in those who underwent transplantation after 2012 (P = .04). Most patients had acute myeloid leukemia (75% vs 69%; P = .26) and were in first complete remission (CR1) (55% vs 64%; P = .12) at the time of transplantation. The cumulative incidence of grade 2, 3, and 4 acute graft-versus-host disease (GvHD) and chronic GvHD were not different between the 2 groups (acute GvHD: 20% vs 22% cumulative incidence in patients who underwent haplo before and after 2012, respectively [P = .67]; chronic GvHD: 19% vs 11% cumulative incidence, respectively; P = .12]. The 2-year relapse incidence was 20%, the nonrelapse mortality (NRM) rate was 48%, and no difference was observed over time (21% vs 19% [P = .72] and 54% vs 38% [P = .11] for patients who underwent haplo before and after 2012, respectively). The main cause of NRM was infection. Haplo after 2012 (hazard ratio [HR], 0.57; P = .01), younger age (HR, 0.82; P = .02), and receipt of a reduced-intensity conditioning (RIC) regimen (HR, 0.53; P = .01) were independently associated with lower NRM. The 2-year overall survival rate was 36% and improved after 2012 (29% vs 47% before 2012; P = .02); and it was higher for patients who underwent transplantation in CR1 (41% vs 29%; P = .01). In multivariate analysis, haplo after 2012 (HR, 0.54; P = .003) and receipt of a RIC regimen (HR, 0.54; P = .005) were independently associated with better overall survival

  6. Long-term outcome after haploidentical stem cell transplant and infusion of T cells expressing the inducible caspase 9 safety transgene.

    PubMed

    Zhou, Xiaoou; Di Stasi, Antonio; Tey, Siok-Keen; Krance, Robert A; Martinez, Caridad; Leung, Kathryn S; Durett, April G; Wu, Meng-Fen; Liu, Hao; Leen, Ann M; Savoldo, Barbara; Lin, Yu-Feng; Grilley, Bambi J; Gee, Adrian P; Spencer, David M; Rooney, Cliona M; Heslop, Helen E; Brenner, Malcolm K; Dotti, Gianpietro

    2014-06-19

    Adoptive transfer of donor-derived T lymphocytes expressing a safety switch may promote immune reconstitution in patients undergoing haploidentical hematopoietic stem cell transplant (haplo-HSCT) without the risk for uncontrolled graft versus host disease (GvHD). Thus, patients who develop GvHD after infusion of allodepleted donor-derived T cells expressing an inducible human caspase 9 (iC9) had their disease effectively controlled by a single administration of a small-molecule drug (AP1903) that dimerizes and activates the iC9 transgene. We now report the long-term follow-up of 10 patients infused with such safety switch-modified T cells. We find long-term persistence of iC9-modified (iC9-T) T cells in vivo in the absence of emerging oligoclonality and a robust immunologic benefit, mediated initially by the infused cells themselves and subsequently by an apparently accelerated reconstitution of endogenous naive T lymphocytes. As a consequence, these patients have immediate and sustained protection from major pathogens, including cytomegalovirus, adenovirus, BK virus, and Epstein-Barr virus in the absence of acute or chronic GvHD, supporting the beneficial effects of this approach to immune reconstitution after haplo-HSCT. This study was registered at www.clinicaltrials.gov as #NCT00710892. © 2014 by The American Society of Hematology.

  7. Long-term outcome after haploidentical stem cell transplant and infusion of T cells expressing the inducible caspase 9 safety transgene

    PubMed Central

    Zhou, Xiaoou; Di Stasi, Antonio; Tey, Siok-Keen; Krance, Robert A.; Martinez, Caridad; Leung, Kathryn S.; Durett, April G.; Wu, Meng-Fen; Liu, Hao; Leen, Ann M.; Savoldo, Barbara; Lin, Yu-Feng; Grilley, Bambi J.; Gee, Adrian P.; Spencer, David M.; Rooney, Cliona M.; Heslop, Helen E.; Brenner, Malcolm K.

    2014-01-01

    Adoptive transfer of donor-derived T lymphocytes expressing a safety switch may promote immune reconstitution in patients undergoing haploidentical hematopoietic stem cell transplant (haplo-HSCT) without the risk for uncontrolled graft versus host disease (GvHD). Thus, patients who develop GvHD after infusion of allodepleted donor-derived T cells expressing an inducible human caspase 9 (iC9) had their disease effectively controlled by a single administration of a small-molecule drug (AP1903) that dimerizes and activates the iC9 transgene. We now report the long-term follow-up of 10 patients infused with such safety switch-modified T cells. We find long-term persistence of iC9-modified (iC9-T) T cells in vivo in the absence of emerging oligoclonality and a robust immunologic benefit, mediated initially by the infused cells themselves and subsequently by an apparently accelerated reconstitution of endogenous naive T lymphocytes. As a consequence, these patients have immediate and sustained protection from major pathogens, including cytomegalovirus, adenovirus, BK virus, and Epstein-Barr virus in the absence of acute or chronic GvHD, supporting the beneficial effects of this approach to immune reconstitution after haplo-HSCT. This study was registered at www.clinicaltrials.gov as #NCT00710892. PMID:24753538

  8. Anti-leukaemic activity of a novel haploidentical-transplantation approach employing unmanipulated bone marrow followed by CD6-depleted peripheral blood stem cells in children with refractory/relapsed acute leukaemia.

    PubMed

    Schuster, Friedhelm R; Meisel, Roland; Führer, Monika; Reuther, Susanne; Hauer, Julia; Tischer, Johanna; Feuchtinger, Tobias; Laws, Hans-Jürgen; Kolb, Hans-Jochem; Borkhardt, Arndt

    2013-09-01

    The treatment outcome of children with refractory acute leukaemia or relapse post-stem cell transplantation is dismal. We report 10 children (non-remission n = 7) who underwent a new haploidentical transplant approach utilizing unmanipulated bone marrow followed by CD6-depleted peripheral blood stem cells. Nine patients had successful engraftment and no evidence of leukaemia. Acute and chronic graft-versus-host-disease was observed in five and three patients, respectively; two patients died of treatment-related toxicity. Seven patients relapsed after 7 (range 3-34) months, however two patients are alive at 6·5 and 7·0 years. This approach provides anti-leukaemic activity even in heavily pre-treated children but long-term disease control requires further intervention. © 2013 John Wiley & Sons Ltd.

  9. Limited tumor infiltration by activated T effector cells restricts the therapeutic activity of regulatory T cell depletion against established melanoma

    PubMed Central

    Quezada, Sergio A.; Peggs, Karl S.; Simpson, Tyler R.; Shen, Yuelei; Littman, Dan R.; Allison, James P.

    2008-01-01

    Interference with inhibitory immunological checkpoints controlling T cell activation provides new opportunities to augment cancer immunotherapies. Whereas cytotoxic T lymphocyte–associated antigen-4 blockade has shown promising preclinical and clinical results, therapeutic CD4+CD25+ T reg cell depletion has failed to consistently enhance immune-based therapies. Using B16/BL6, a transplantable murine melanoma model, we show a dichotomy between the effects of T reg cell depletion on tumor rejection dependent on whether depletion occurs before (prophylactic) or after (therapeutic) tumor engraftment. Failure to promote rejection with therapeutic depletion is not related to lack of T reg cell depletion, to elimination of CD25+ effector T cells, or to a failure to enhance systemic antitumor T cell responses, but correlates with failure of effector cells to infiltrate the tumor and increase the intratumor ratio of effector T cell/T reg cell. Finally, systemic antitumor responses generated upon therapeutic T reg cell depletion are significantly stronger than those generated in the presence of T reg cells, and are capable of eliciting rejection of established tumors after transfer into immunoablated recipients receiving combination immunotherapy. The data demonstrate a dissociation between measurable systemic responses and tumor rejection during CD25-directed T reg cell depletion, and suggest an alternative, clinically applicable strategy for the treatment of established tumors. PMID:18725522

  10. T-cell-replete haploidentical stem cell transplantation is highly efficacious for relapsed and refractory childhood acute leukaemia.

    PubMed

    Kobayashi, S; Ito, M; Sano, H; Mochizuki, K; Akaihata, M; Waragai, T; Ohara, Y; Hosoya, M; Ohto, H; Kikuta, A

    2014-10-01

    Despite improvements in first-line therapies, the outcomes of relapsed or refractory childhood acute leukaemia that has not achieved complete remission after relapse, has relapsed after stem cell transplantation (SCT), has primary induction failure and has relapsed with a very unfavourable cytogenetic risk profile, are dismal. We evaluated the feasibility and efficacy of T-cell-replete haploidentical peripheral blood stem cell transplantation (haplo-SCT) with low-dose anti-human thymocyte immunoglobulin (ATG), tacrolimus, methotrexate and prednisolone (PSL) in 14 paediatric patients with high-risk childhood acute leukaemia. All patients achieved complete engraftment. The median time to reaching an absolute neutrophil count of more than 0.5 × 10(9) L(-1) was 14 days. Acute graft-vs-host disease (aGVHD) of grades II-IV and III-IV developed in 10 (71%) and 2 (14%) patients, respectively. Treatment-related mortality and relapse occurred in one (7%) patient and six (43%) patients, respectively. Eleven patients were alive and seven of them were disease-free with a median follow-up of 36 months (range: 30-159 months). The probability of event-free survival after 2 years was 50%. These findings indicate that T-cell-replete haplo-SCT, with low-dose ATG and PSL, provides sustained remission with an acceptable risk of GVHD in paediatric patients with advanced haematologic malignancies. © 2014 The Authors. Transfusion Medicine published by John Wiley & Sons Ltd on behalf of British Blood Transfusion Society.

  11. Haploidentical Hematopoietic Stem Cell Transplantation as Platform for Post-transplant Cellular Therapy

    PubMed Central

    Kongtim, Piyanuch; Lee, Dean A.; Cooper, Laurence J. N.; Kebriaei, Partow; Champlin, Richard E.; Ciurea, Stefan O.

    2016-01-01

    Haploidentical transplantation can extend the opportunity for transplantation to almost all patients who lack an HLA-matched donor. Advances in the field of haploidentical transplantation have led to a marked decrease in treatment-related mortality, allowing investigators to focus on developing rationale pre- and peri-remission therapies aimed at preventing disease relapse post-transplant. Due to widespread availability, low treatment-related mortality and cost, haploidentical donors may become the preferred “alternative” donors for allogeneic hematopoietic stem cell transplantation. One of the major advantages of using a related donor is the possibility to collect or generate additional cellular products from the same immediate available donor, which will not be rejected. Infusion of these cells in the peri-transplant period, derived from the same immune system, is opening the possibility to markedly enhance the anti-tumor effects of the graft and hasten immunologic reconstitution post-transplant. PMID:26172479

  12. IL-7 receptor blockade following T cell depletion promotes long-term allograft survival

    PubMed Central

    Mai, Hoa-Le; Boeffard, Françoise; Longis, Julie; Danger, Richard; Martinet, Bernard; Haspot, Fabienne; Vanhove, Bernard; Brouard, Sophie; Soulillou, Jean-Paul

    2014-01-01

    T cell depletion is commonly used in organ transplantation for immunosuppression; however, a restoration of T cell homeostasis following depletion leads to increased memory T cells, which may promote transplant rejection. The cytokine IL-7 is important for controlling lymphopoiesis under both normal and lymphopenic conditions. Here, we investigated whether blocking IL-7 signaling with a mAb that targets IL-7 receptor α (IL-7Rα) alone or following T cell depletion confers an advantage for allograft survival in murine transplant models. We found that IL-7R blockade alone induced indefinite pancreatic islet allograft survival if anti–IL-7R treatment was started 3 weeks before graft. IL-7R blockade following anti-CD4– and anti-CD8–mediated T cell depletion markedly prolonged skin allograft survival. Furthermore, IL-7 inhibition in combination with T cell depletion synergized with either CTLA-4Ig administration or suboptimal doses of tacrolimus to induce long-term skin graft acceptance in this stringent transplant model. Together, these therapies inhibited T cell reconstitution, decreased memory T cell numbers, increased the relative frequency of Tregs, and abrogated both cellular and humoral alloimmune responses. Our data suggest that IL-7R blockade following T cell depletion has potential as a robust, immunosuppressive therapy in transplantation. PMID:24569454

  13. B cell depletion reduces T cell activation in pancreatic islets in a murine autoimmune diabetes model.

    PubMed

    Da Rosa, Larissa C; Boldison, Joanne; De Leenheer, Evy; Davies, Joanne; Wen, Li; Wong, F Susan

    2018-06-01

    Type 1 diabetes is a T cell-mediated autoimmune disease characterised by the destruction of beta cells in the islets of Langerhans, resulting in deficient insulin production. B cell depletion therapy has proved successful in preventing diabetes and restoring euglycaemia in animal models of diabetes, as well as in preserving beta cell function in clinical trials in the short term. We aimed to report a full characterisation of B cell kinetics post B cell depletion, with a focus on pancreatic islets. Transgenic NOD mice with a human CD20 transgene expressed on B cells were injected with an anti-CD20 depleting antibody. B cells were analysed using multivariable flow cytometry. There was a 10 week delay in the onset of diabetes when comparing control and experimental groups, although the final difference in the diabetes incidence, following prolonged observation, was not statistically significant (p = 0.07). The co-stimulatory molecules CD80 and CD86 were reduced on stimulation of B cells during B cell depletion and repopulation. IL-10-producing regulatory B cells were not induced in repopulated B cells in the periphery, post anti-CD20 depletion. However, the early depletion of B cells had a marked effect on T cells in the local islet infiltrate. We demonstrated a lack of T cell activation, specifically with reduced CD44 expression and effector function, including IFN-γ production from both CD4 + and CD8 + T cells. These CD8 + T cells remained altered in the pancreatic islets long after B cell depletion and repopulation. Our findings suggest that B cell depletion can have an impact on T cell regulation, inducing a durable effect that is present long after repopulation. We suggest that this local effect of reducing autoimmune T cell activity contributes to delay in the onset of autoimmune diabetes.

  14. Haploidentical stem cell transplantation for children with high-risk leukemia.

    PubMed

    Palma, Julia; Salas, Lucia; Carrión, Flavio; Sotomayor, Cristián; Catalán, Paula; Paris, Claudia; Turner, Victoria; Jorquera, Hugo; Handgretinger, Rupert; Rivera, Gastón K

    2012-11-01

    The Chilean population is ethnically diverse, and more than 50% of children referred for hematopoietic stem cell transplantation (HSCT) lack a suitable donor. To expand the donor pool, we assessed the feasibility, tolerance, and efficacy of using a haploidentical (HI) donor and a reduced-intensity conditioning regimen for high-risk pediatric leukemia. This study was facilitated by technology transfer from St. Jude Children's Research Hospital over the 2 preceding years. Between March 2006 and April 2009, 10 patients (median age, 9.8 years) received T cell-depleted grafts at Calvo Mackenna Hospital in Santiago. Median cell doses were CD34+: 7.45 × 10(6)/kg (range, 4.00-20.20 × 10(6)/kg); CD3+: 0.88 × 10(5)/kg (0.11-1.35 × 10(5)/kg); and CD56+: 71.30 × 10(6)/kg (31.50-131.80 × 10(6)/kg). Nine patients experienced complete engraftment; six of the nine remain alive and clinically well 13-50 months post-HSCT. Three patients died after bone marrow relapse, while only one died of transplant-related causes. Virus reactivation was the main post-transplant complication: 5/10 had positive CMV PCR but none had CMV disease. One patient developed acute GvHD > grade II and only one had chronic GvHD. HI-HSCT is feasible in our setting, offers a rational treatment option, and expands the donor pool significantly for children with high-risk leukemia in a developing country. This information is especially relevant to other ethnically diverse populations that are poorly represented in international donor registries. Copyright © 2012 Wiley Periodicals, Inc.

  15. Causes of mortality after haploidentical hematopoietic stem cell transplantation and the comparison with HLA-identical sibling hematopoietic stem cell transplantation.

    PubMed

    Yan, C H; Xu, L P; Wang, F R; Chen, H; Han, W; Wang, Yu; Wang, J Z; Liu, K Y; Huang, X J

    2016-03-01

    This study was performed to investigate incidence, causes and factors influencing mortality after haploidentical hematopoietic stem cell transplantation (HSCT) and to compare differences between haploidentical HSCT and HLA-identical sibling HSCT. From January 2000 to June 2011, 1411 patients with acute leukemia or myelodysplastic syndrome were included in this study. Of these patients, 571 received HLA-identical sibling HSCT and 840 received haploidentical HSCT. The cumulative incidence of overall mortality and transplant-related mortality (TRM) after haploidentical HSCT was higher than those after HLA-identical sibling HSCT (38.7% vs. 33.3%, P=0.012 and 27.5% vs. 19.9%, P=0.002), but the incidence of relapse-related mortality (RRM) did not differ between the two groups (15.6% vs. 16.7%, P=0.943). A multivariate analysis suggested that high-risk disease status and haploidentical HSCT correlated with a higher incidence of overall mortality (P<0.0001, hazard ratio=1.911 and P=0.019, hazard ratio=1.249); in addition, in haploidentical HSCT, only high-risk disease status correlated with a higher incidence of overall mortality (P<0.0001, hazard ratio=1.845). Our study suggested that haploidentical HSCT provided a higher incidence of overall mortality and TRM but the same incidence of RRM compared with HLA-identical sibling HSCT. Therefore, HLA-identical sibling HSCT remains the first choice, but haploidentical HSCT is available for patients without an HLA-identical sibling donor.

  16. Curative or pre-emptive adenovirus-specific T cell transfer from matched unrelated or third party haploidentical donors after HSCT, including UCB transplantations: a successful phase I/II multicenter clinical trial.

    PubMed

    Qian, Chongsheng; Campidelli, Arnaud; Wang, Yingying; Cai, Huili; Venard, Véronique; Jeulin, Hélène; Dalle, Jean Hugues; Pochon, Cécile; D'aveni, Maud; Bruno, Benedicte; Paillard, Catherine; Vigouroux, Stéphane; Jubert, Charlotte; Ceballos, Patrice; Marie-Cardine, Aude; Galambrun, Claire; Cholle, Clément; Clerc Urmes, Isabelle; Petitpain, Nadine; De Carvalho Bittencourt, Marcelo; Decot, Véronique; Reppel, Loïc; Salmon, Alexandra; Clement, Laurence; Bensoussan, Danièle

    2017-05-08

    Allogeneic hematopoietic stem cell transplantation (HSCT), the most widely used potentially curable cellular immunotherapeutic approach in the treatment of hematological malignancies, is limited by life-threatening complications: graft versus host disease (GVHD) and infections especially viral infections refractory to antiviral drugs. Adoptive transfer of virus-specific T cells is becoming an alternative treatment for infections following HSCT. We report here the results of a phase I/II multicenter study which includes a series of adenovirus-specific T cell (ADV-VST) infusion either from the HSCT donor or from a third party haploidentical donor for patients transplanted with umbilical cord blood (UCB). Fourteen patients were eligible and 11 patients received infusions of ADV-VST generated by interferon (IFN)-γ-based immunomagnetic isolation from a leukapheresis from their original donor (42.9%) or a third party haploidentical donor (57.1%). One patient resolved ADV infection before infusion, and ADV-VST could not reach release or infusion criteria for two patients. Two patients received cellular immunotherapy alone without antiviral drugs as a pre-emptive treatment. One patient with adenovirus infection and ten with adenovirus disease were infused with ADV-VST (mean 5.83 ± 8.23 × 10 3 CD3+IFN-γ+ cells/kg) up to 9 months after transplantation. The 11 patients showed in vivo expansion of specific T cells up to 60 days post-infusion, associated with adenovirus load clearance in ten of the patients (91%). Neither de novo GVHD nor side effects were observed during the first month post-infusion, but GVHD reactivations occurred in three patients, irrespective of the type of leukapheresis donor. For two of these patients, GVHD reactivation was controlled by immunosuppressive treatment. Four patients died during follow-up, one due to refractory ADV disease. Adoptive transfer of rapidly isolated ADV-VST is an effective therapeutic option for achieving in vivo

  17. The early expansion of anergic NKG2Apos/CD56dim/CD16neg natural killer cells represents a therapeutic target in haploidentical haematopoietic stem cell transplantation.

    PubMed

    Roberto, Alessandra; Di Vito, Clara; Zaghi, Elisa; Mazza, Emilia Maria Cristina; Capucetti, Arianna; Calvi, Michela; Tentorio, Paolo; Zanon, Veronica; Sarina, Barbara; Mariotti, Jacopo; Bramanti, Stefania; Tenedini, Elena; Tagliafico, Enrico; Bicciato, Silvio; Santoro, Armando; Roederer, Mario; Marcenaro, Emanuela; Castagna, Luca; Lugli, Enrico; Mavilio, Domenico

    2018-04-26

    Natural Killer cells are the first lymphocyte population to reconstitute early after non myelo-ablative and T cell-replete haploidentical hematopoietic stem cell transplantation with post-transplant infusion of cyclophosphamide. The present study characterizes the transient and predominant expansion starting from the 2nd week after haploidentical hematopoietic stem cell transplantation of a donor-derived unconventional subset of NKp46neg-low/CD56dim/CD16neg natural killer cells expressing remarkable high levels of CD94/NKG2A. Both transcription and phenotypic profiles indicated that unconventional NKp46neg-low/CD56dim/CD16neg natural killer cells are a distinct natural killer cell subpopulation with features of late stage differentiation, yet retaining proliferative capability and functional plasticity to generate conventional NKp46pos/CD56bright/CD16pos natural killer cells in response to interleukin-15 plus interleukin-18. While present at low frequency in healthy donors, unconventional NKp46neg-low/CD56dim/CD16neg natural killer cells are greatly expanded in the following 7 weeks after haploidentical hematopoietic stem cell transplantation and express high levels of the activating receptors NKGD and NKp30 as well as of the lytic granules Granzyme-B and Perforin. Nonetheless, NKp46neg-low/CD56dim/CD16neg natural killer cells displayed a markedly defective cytotoxicity that could be reversed by blocking the inhibitory receptor CD94/NKG2A. These data open new important perspectives to better understand the ontogenesis/homeostasis of human natural killer cells and to develop a novel immune-therapeutic approach that targets the inhibitory NKG2A check point, thus unleashing natural killer cell alloreactivity early after haploidentical hematopoietic stem cell transplantation. Copyright © 2018, Ferrata Storti Foundation.

  18. Riboflavin Depletion Promotes Tumorigenesis in HEK293T and NIH3T3 Cells by Sustaining Cell Proliferation and Regulating Cell Cycle-Related Gene Transcription.

    PubMed

    Long, Lin; He, Jian-Zhong; Chen, Ye; Xu, Xiu-E; Liao, Lian-Di; Xie, Yang-Min; Li, En-Min; Xu, Li-Yan

    2018-05-07

    Riboflavin is an essential component of the human diet and its derivative cofactors play an established role in oxidative metabolism. Riboflavin deficiency has been linked with various human diseases. The objective of this study was to identify whether riboflavin depletion promotes tumorigenesis. HEK293T and NIH3T3 cells were cultured in riboflavin-deficient or riboflavin-sufficient medium and passaged every 48 h. Cells were collected every 5 generations and plate colony formation assays were performed to observe cell proliferation. Subcutaneous tumorigenicity assays in NU/NU mice were used to observe tumorigenicity of riboflavin-depleted HEK293T cells. Mechanistically, gene expression profiling and gene ontology analysis were used to identify abnormally expressed genes induced by riboflavin depletion. Western blot analyses, cell cycle analyses, and chromatin immunoprecipitation were used to validate the expression of cell cycle-related genes. Plate colony formation of NIH3T3 and HEK293T cell lines was enhanced >2-fold when cultured in riboflavin-deficient medium for 10-20 generations. Moreover, we observed enhanced subcutaneous tumorigenicity in NU/NU mice following injection of riboflavin-depleted compared with normal HEK293T cells (55.6% compared with 0.0% tumor formation, respectively). Gene expression profiling and gene ontology analysis revealed that riboflavin depletion induced the expression of cell cycle-related genes. Validation experiments also found that riboflavin depletion decreased p21 and p27 protein levels by ∼20%, and increased cell cycle-related and expression-elevated protein in tumor (CREPT) protein expression >2-fold, resulting in cyclin D1 and CDK4 levels being increased ∼1.5-fold, and cell cycle acceleration. We also observed that riboflavin depletion decreased intracellular riboflavin levels by 20% and upregulated expression of riboflavin transporter genes, particularly SLC52A3, and that the changes in CREPT and SLC52A3 correlated with

  19. Recipient-donor KIR ligand matching prevents CMV reactivation post-haploidentical T cell-replete transplantation.

    PubMed

    Zhao, Xiang-Yu; Luo, Xue-Yi; Yu, Xing-Xing; Zhao, Xiao-Su; Han, Ting-Ting; Chang, Ying-Jun; Huo, Ming-Rui; Xu, Lan-Ping; Zhang, Xiao-Hui; Liu, Kai-Yan; Li, Dan; Jiang, Zheng-Fan; Huang, Xiao-Jun

    2017-06-01

    Licensed natural killer (NK) cells have been demonstrated to have anti-cytomegalovirus (CMV) activity. We prospectively analysed the human leucocyte antigen typing of donor-recipient pairs and the killer cell immunoglobulin-like receptor (KIR) typing of donors for 180 leukaemia patients to assess the predictive roles of licensed NK cells on CMV reactivation post-T-cell-replete haploidentical stem cell transplantation. Multivariate analysis showed that donor-recipient KIR ligand graft-versus-host or host-versus-graft direction mismatch was associated with increased refractory CMV infection (Hazard ratio = 2·556, 95% confidence interval, 1·377-4·744, P = 0·003) post-transplantation. Donor-recipient KIR ligand matching decreased CMV reactivation [51·65% (46·67, 56·62%) vs. 75·28% (70·87, 79·69%), P = 0·012], refractory CMV infection [17·58% (13·77, 21·40%) vs. 35·96% (31·09, 40·82%), P = 0·004] and CMV disease [3·30% (1·51, 5·08%) vs. 11·24% (8·04, 14·43%), P = 0·024] by day 100 post-transplantation. In addition, the percentage of γ-interferon expression on donor-derived NK cells was significantly higher in the recipients among the recipient-donor pairs with a KIR ligand match compared with that in the recipients among the pairs with a KIR ligand graft-versus-host or host-versus-graft direction mismatch on days 30 and 100 post-transplantation (P = 0·036 and 0·047, respectively). These findings have suggested that donor-recipient KIR ligand matching might promote the NK cell licensing process, thereby increasing NK cell-mediated protection against CMV reactivation. © 2017 John Wiley & Sons Ltd.

  20. Treatment of acute leukemia with unmanipulated HLA-mismatched/haploidentical blood and bone marrow transplantation.

    PubMed

    Huang, Xiao-Jun; Liu, Dai-Hong; Liu, Kai-Yan; Xu, Lan-Ping; Chen, Huan; Han, Wei; Chen, Yu-Hong; Zhang, Xiao-Hui; Lu, Dao-Pei

    2009-02-01

    Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains one of the best therapeutic options to cure acute leukemia (AL). However, many patients have no human leukocyte antigen (HLA)-matched donor. Recently, we developed a new method for HLA-mismatched/haploidentical transplantation without in vitro T cell depletion (TCD). This method combined granulocyte-colony stimulating factor (G-CSF)-primed bone marrow and peripheral blood with intensive immunosuppression. We analyzed the outcome of 250 consecutive patients with AL who underwent HLA-mismatched/haploidentical transplantation with 1-3 mismatched loci of HLA-A, B, and DR from family donors via our new transplant protocol. Two hundred forty-nine patients achieved sustained, full donor chimerism. The incidence of grade 2-4 acute graft-versus-host disease (aGVHD) was 45.8%, and that of grades 3 and 4 was 13.4%, which was not associated with the extent of HLA disparity. The cumulative incidence of total chronic GVHD (cGVHD) was 53.9% and that of extensive cGVHD was 22.6% in 217 evaluable patients. One hundred forty-one of the 250 patients survived free of disease recurrence at a median of 1092 days (range: 442-2437 days) of follow-up. Seventeen patients received DLI as a treatment for relapse after transplantation and 7 patients achieved leukemia-free survival (LFS). The 3-year probability of LFS for acute myelogenous leukemia (AML) was 70.7% and 55.9%, and for acute lymphoblastic leukemia (ALL) it was 59.7% and 24.8% in standard-risk and high-risk groups, respectively. Lower LFS were associated with diagnosis of acute leukemia in the high-risk group (P= .001, relative risk [RR], 95% confidence interval [CI]: 2.94[1.535-5.631]) and the occurrence of aGVHD of grades 3 and 4 (P= .004). HLA-mismatched/haploidentical HSCT was feasible with unmanipulated blood and bone marrow harvest.

  1. In vitro generation of Epstein-Barr virus-specific cytotoxic T cells in patients receiving haplo-identical allogeneic stem cell transplantation.

    PubMed

    Musk, P; Szmania, S; Galloway, A T; Johnson, K; Scott, A; Guttman, S; Bridges, K; Bruorton, M; Gatlin, J; Garcia, J V; Lamb, L; Chiang, K Y; Spencer, T; Henslee-Downey, J; van Rhee, F

    2001-01-01

    Use of a partially mismatched related donor (PMRD) is an option for patients who require allogeneic transplantation but do not have a matched sibling or unrelated donor. Epstein-Barr virus (EBV)-induced lymphoma is a major cause of mortality after PMRD transplantation. In this study, we present a clinical grade culture system for donor-derived EBV-specific cytotoxic T cells (CTLs) that do not recognize haplo-identical recipient cells. The EBV-specific CTLs were tested for cytolytic specificity and other functional properties, including ability to transgress into tissues, propensity for apoptosis, degree of clonality, stability of dominant T-cell clones, and Tc and Th phenotypes. The EBV-specific CTLs were routinely expanded to greater than 80 x 10(6) over a period of 5 weeks, which is sufficient for clinical application. A CD8+ phenotype predominated, and the CTLs were highly specific for donor lymphoblastoid cell lines (LCLs) without killing of recipient targets or K562. Vbeta spectratyping showed an oligoclonal population that was stable on prolonged culture. The EBV-specific CTLs were activated (D-related human leukocyte antigen [HLA-DR+], L-selectin+/-) and of memory phenotype (CD45RO+). Expression of the integrin VLA-4 suggested that these CTLs could adhere to endothelium and migrate into tissues. The Bcl-2 message was upregulated, which may protect the CTLs from the apoptosis. The first demonstration of overexpression of bcl-2 in human memory CTLs. In addition, we show that lymphoblastoid cell lines used to generate CTLs are readily genetically modified with recombinant lentivirus, indicating that genetically engineered antigen presentation is feasible.

  2. CD4 T Cell Depletion Exacerbates Acute Mycobacterium tuberculosis While Reactivation of Latent Infection Is Dependent on Severity of Tissue Depletion in Cynomolgus Macaques

    PubMed Central

    Lin, Philana Ling; Rutledge, Tara; Green, Angela M.; Bigbee, Matthew; Fuhrman, Carl; Klein, Edwin

    2012-01-01

    Abstract CD4 T cells are believed to be important in protection against Mycobacterium tuberculosis, but the relative contribution to control of initial or latent infection is not known. Antibody-mediated depletion of CD4 T cells in M. tuberculosis-infected cynomolgus macaques was used to study the role of CD4 T cells during acute and latent infection. Anti-CD4 antibody severely reduced levels of CD4 T cells in blood, airways, and lymph nodes. Increased pathology and bacterial burden were observed in CD4-depleted monkeys during the first 8 weeks of infection compared to controls. CD4-depleted monkeys had greater interferon (IFN)-γ expression and altered expression of CD8 T cell activation markers. During latent infection, CD4 depletion resulted in clinical reactivation in only three of six monkeys. Reactivation was associated with lower CD4 T cells in the hilar lymph nodes. During both acute and latent infection, CD4 depletion was associated with reduced percentages of CXCR3+ expressing CD8 T cells, reported to be involved in T cell recruitment, regulatory function, and effector and memory T cell maturation. CXCR3+ CD8 T cells from hilar lymph nodes had more mycobacteria-specific cytokine expression and greater coexpression of multiple cytokines compared to CXCR3− CD8 T cells. CD4 T cells are required for protection against acute infection but reactivation from latent infection is dependent on the severity of depletion in the draining lymph nodes. CD4 depletion influences CD8 T cell function. This study has important implications for human HIV–M. tuberculosis coinfection. PMID:22480184

  3. T Cell-Replete Peripheral Blood Haploidentical Hematopoietic Cell Transplantation with Post-Transplantation Cyclophosphamide Results in Outcomes Similar to Transplantation from Traditionally Matched Donors in Active Disease Acute Myeloid Leukemia.

    PubMed

    How, Joan; Slade, Michael; Vu, Khoan; DiPersio, John F; Westervelt, Peter; Uy, Geoffrey L; Abboud, Camille N; Vij, Ravi; Schroeder, Mark A; Fehniger, Todd A; Romee, Rizwan

    2017-04-01

    Outcomes for patients with acute myeloid leukemia (AML) who fail to achieve complete remission remain poor. Hematopoietic cell transplantation (HCT) has been shown to induce long-term survival in AML patients with active disease. HCT is largely performed with HLA-matched unrelated or HLA-matched related donors. Recently, HCT with HLA-haploidentical related donors has been identified as a feasible option when HLA-matched donors are not immediately available. However, there are little data comparing outcomes for AML patients with active disease who receive haploidentical versus traditionally matched HCT. We retrospectively analyzed data from 99 AML patients with active disease undergoing allogeneic HCT at a single institution. Forty-three patients received unrelated donor HCT, 32 patients received matched related donor HCT, and 24 patients received peripheral blood haploidentical HCT with post-transplantation cyclophosphamide. We found no significant differences between treatment groups in terms of overall survival (OS), event-free survival, transplantation-related mortality, cumulative incidence of relapse, and cumulative incidence of acute and chronic graft-versus-host disease (GVHD). We performed univariate regression analysis of variables that modified OS in all patients and found only younger age at transplantation and development of chronic GVHD significantly improved outcome. Although limited by our relatively small sample size, these results indicate that haploidentical HCT in active AML patients have comparable outcomes to HCT with traditionally matched donors. Haploidentical HCT can be considered in this population of high-risk patients when matched donors are unavailable or when wait times for transplantation are unacceptably long. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  4. In vivo T cell depletion regulates resistance and morbidity in murine schistosomiasis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Phillips, S.M.; Linette, G.P.; Doughty, B.L.

    1987-08-01

    These studies assessed the roles of subpopulations of T lymphocytes in inducing and modulating resistance to schistosomiasis and thereby influencing subsequent morbidity. C57BL/6 mice were depleted in vivo of Lyt-1+, Lyt-2+, and L3T4+ cells by the daily administration of monoclonal antibodies. The development of protective immunity, induced by exposure to irradiated Schistosoma mansoni cercariae as expressed in depleted animals, was compared to that demonstrated in undepleted, normal, and congenitally athymic C57BL/6 mice. The development of morbidity was determined by spleen weight, portal pressure and reticuloendothelial system activity. The results indicated that depletion of specific subpopulations of T lymphocytes minimally affectedmore » the primary development of parasites; however, depletion strongly influenced the development of resistance to the parasite and subsequent morbidity due to infection. Depletion of T lymphocytes by anti-Lyt-1+ or anti-L3T4+ antibody decreased the development of resistance, antibody and delayed-type hypersensitivity directed against schistosome antigens. Morbidity due to disease was increased. Depletion of Lyt-2+ cells produced opposite changes with augmented resistance and reduced morbidity. Congenitally athymic mice developed minimal resistance and morbidity. Moreover, resistance was inversely related to the morbidity shown by a given animal. These studies indicate that the development of protective immunity to S. mansoni cercariae is regulated by discrete subpopulations of T lymphocytes. The feasibility of decreasing morbidity by increasing specific immunologically mediated resistance is suggested.« less

  5. Challenges of T Cell Therapies for Virus-associated Diseases after Hematopoietic Stem Cell Transplantation

    PubMed Central

    Leen, Ann M.; Tripic, Tamara; Rooney, Cliona M.

    2009-01-01

    Importance of the field Hematopoietic stem cell transplantation (HSCT) is the treatment of choice for many hematological malignancies and genetic disorders. A majority of patients do not have a human leukocyte antigen (HLA) identical sibling donor, and alternative stem cell sources include HLA-matched or mismatched unrelated donors and haploidentical related donors. However, alternative donor HSCT are associated with three major complications (i) graft rejection, (ii) graft-versus-host disease (GvHD) and (iii) delayed immune reconstitution leading to viral infections and relapse. Areas covered in this review Graft rejection and the risk of GvHD can be significantly reduced by using intensive conditioning regimens, including in vivo T cell depletion as well as ex vivo T cell depletion of the graft. However, the benefits of removing alloreactive T cells from the graft are offset by the concomitant removal of T cells with anti-viral or anti-tumor activity as well as the profound delay in endogenous T cell recovery post-transplant. Thus, opportunistic infections, many of which are not amenable to conventional small-molecule therapeutics, are frequent in these patients and are associated with significant morbidity and high mortality rates. This review discusses current cell therapies to prevent or treat viral infections/reactivations post-transplant. What the reader will gain The reader will gain an understanding of the current state of cell therapy to prevent and treat viral infections post-HSCT, and will be introduced to preclinical studies designed to develop and validate new manufacturing procedures intended to improve therapeutic efficacy and reduce associated toxicities. Take home message Reconstitution of HSCT recipients with antigen-specific T cells, produced either by allodepletion or in vitro reactivation, can offer an effective strategy to provide both immediate and long-term protection without harmful alloreactivity. PMID:20132056

  6. Depletion of FAP+ cells reduces immunosuppressive cells and improves metabolism and functions CD8+T cells within tumors

    PubMed Central

    Zhang, Ying; Ertl, Hildegund C.J.

    2016-01-01

    The tumor stroma, which is essential to support growth and metastasis of malignant cells, provides targets for active immunotherapy of cancer. Previous studies have shown that depleting fibroblast activation protein (FAP)-expressing stromal cells reduces tumor progression and concomitantly increases tumor antigen (TA)-specific T cell responses. However the underlying pathways remain ill defined. Here we identify that immunosuppressive cells (ISCs) from tumor-bearing mice impose metabolic stress on CD8+T cells, which is associated with increased expression of the co-inhibitor PD-1. In two mouse melanoma models, depleting FAP+ stroma cells from the tumor microenvironment (TME) upon vaccination with an adenoviral-vector reduces frequencies and functions of ISCs. This is associated with changes in the cytokine/chemokine milieu in the TME and decreased activity of STAT6 signaling within ISCs. Decreases in ISCs upon FAP+stromal cell depletion is associated with reduced metabolic stress of vaccine-induced tumor infiltrating CD8+T cells and their delayed progression towards functional exhaustion, resulting in prolonged survival of tumor-bearing mice. PMID:26943036

  7. Depletion of FAP+ cells reduces immunosuppressive cells and improves metabolism and functions CD8+T cells within tumors.

    PubMed

    Zhang, Ying; Ertl, Hildegund C J

    2016-04-26

    The tumor stroma, which is essential to support growth and metastasis of malignant cells, provides targets for active immunotherapy of cancer. Previous studies have shown that depleting fibroblast activation protein (FAP)-expressing stromal cells reduces tumor progression and concomitantly increases tumor antigen (TA)-specific T cell responses. However the underlying pathways remain ill defined. Here we identify that immunosuppressive cells (ISCs) from tumor-bearing mice impose metabolic stress on CD8+T cells, which is associated with increased expression of the co-inhibitor PD-1. In two mouse melanoma models, depleting FAP+ stroma cells from the tumor microenvironment (TME) upon vaccination with an adenoviral-vector reduces frequencies and functions of ISCs. This is associated with changes in the cytokine/chemokine milieu in the TME and decreased activity of STAT6 signaling within ISCs. Decreases in ISCs upon FAP+stromal cell depletion is associated with reduced metabolic stress of vaccine-induced tumor infiltrating CD8+T cells and their delayed progression towards functional exhaustion, resulting in prolonged survival of tumor-bearing mice.

  8. Ex vivo T-cell-depleted allogeneic stem cell transplantation for hematologic malignancies: The search for an optimum transplant T-cell dose and T-cell add-back strategy.

    PubMed

    Anandi, Prathima; Tian, Xin; Ito, Sawa; Muranski, Pawel; Chokshi, Puja D; Watters, Noelle; Chawla, Upneet; Hensel, Nancy; Stroncek, David F; Battiwalla, Minoo; Barrett, A John

    2017-06-01

    T-cell depletion (TCD) of allogeneic stem cell transplants (SCT) can reduce graft-versus-host disease but may negatively affect transplant outcome by delaying immune recovery. To optimize TCD in HLA-matched siblings with hematologic malignancies, we explored varying the transplant CD3+ T-cell dose between 2 and 50 × 10 4 /kg (corresponding to 3-4 log depletion) and studied the impact of 0-6 × 10 7 /kg CD3+ donor lymphocyte infusion (DLI) "add-back" on immune recovery post-SCT. Two hundred seventeen consecutive patients (age range, 10-75 years) with hematologic malignancy (excluding chronic leukemias) underwent ex vivo TCD SCT from HLA-identical sibling donors from 1994-2015. Ninety-four patients had standard-risk disease (first remission acute leukemia [AL] and early stage myelodysplastic syndromes [MDS]) and 123 had high-risk disease (AL beyond first complete remission, advanced MDS or refractory B-cell malignancy). Median follow-up was 8.5 years. At 20 years post-SCT, overall survival (OS) was 40%, nonrelapse mortality (NRM) was 27% and relapse incidence was 39%. Factors affecting outcome in multivariate analysis were transplantation era, with OS increasing from 38% in the period 1994-2000 to 58% in 2011-2015, disease risk (hazard ratio [HR], 1.68 for high risk) and increasing age (HR, 1.19 per decade). Neither the T-cell dose or the add back of T cells in the first 100 days had any effect on OS, NRM and relapse. Outcomes for TCD SCT have greatly improved. However, our data do not support the need to precisely manipulate transplant CD3+ T-cell dose provided at least 3-log depletion is achieved or the use of T-cell add-back. Future improvements for TCD SCT await better strategies to prevent relapse, especially in high-risk recipients. Published by Elsevier Inc.

  9. Early recovery of T-cell function predicts improved survival after T-cell depleted allogeneic transplant.

    PubMed

    Goldberg, Jenna D; Zheng, Junting; Ratan, Ravin; Small, Trudy N; Lai, Kuan-Chi; Boulad, Farid; Castro-Malaspina, Hugo; Giralt, Sergio A; Jakubowski, Ann A; Kernan, Nancy A; O'Reilly, Richard J; Papadopoulos, Esperanza B; Young, James W; van den Brink, Marcel R M; Heller, Glenn; Perales, Miguel-Angel

    2017-08-01

    Infection, relapse, and GVHD can complicate allogeneic hematopoietic stem cell transplantation (allo-HSCT). Although the effect of poor immune recovery on infection risk is well-established, there are limited data on the effect of immune reconstitution on relapse and survival, especially following T-cell depletion (TCD). To characterize the pattern of immune reconstitution in the first year after transplant and its effects on survival and relapse, we performed a retrospective study in 375 recipients of a myeloablative TCD allo-HSCT for hematologic malignancies. We noted that different subsets recover sequentially, CD8 + T cells first, followed by total CD4 + and naïve CD4 + T cells, indicating thymic recovery during the first year after HSCT. In the multivariate model, a fully HLA-matched donor and recovery of T-cell function, assessed by PHA response at 6 months, were the only factors independently associated with OS and EFS. In conclusion, T-cell recovery is an important predictor of outcome after TCD allo-HSCT.

  10. Adoptive cell therapy for lymphoma with CD4 T cells depleted of CD137-expressing regulatory T cells.

    PubMed

    Goldstein, Matthew J; Kohrt, Holbrook E; Houot, Roch; Varghese, Bindu; Lin, Jack T; Swanson, Erica; Levy, Ronald

    2012-03-01

    Adoptive immunotherapy with antitumor T cells is a promising novel approach for the treatment of cancer. However, T-cell therapy may be limited by the cotransfer of regulatory T cells (T(reg)). Here, we explored this hypothesis by using 2 cell surface markers, CD44 and CD137, to isolate antitumor CD4 T cells while excluding T(regs). In a murine model of B-cell lymphoma, only CD137(neg)CD44(hi) CD4 T cells infiltrated tumor sites and provided protection. Conversely, the population of CD137(pos)CD44hi CD4 T cells consisted primarily of activated T(regs). Notably, this CD137(pos) T(reg) population persisted following adoptive transfer and maintained expression of FoxP3 as well as CD137. Moreover, in vitro these CD137(pos) cells suppressed the proliferation of effector cells in a contact-dependent manner, and in vivo adding the CD137(pos)CD44(hi) CD4 cells to CD137(neg)CD44(hi) CD4 cells suppressed the antitumor immune response. Thus, CD137 expression on CD4 T cells defined a population of activated T(regs) that greatly limited antitumor immune responses. Consistent with observations in the murine model, human lymphoma biopsies also contained a population of CD137(pos) CD4 T cells that were predominantly CD25(pos)FoxP3(pos) T(regs). In conclusion, our findings identify 2 surface markers that can be used to facilitate the enrichment of antitumor CD4 T cells while depleting an inhibitory T(reg) population.

  11. Tolerance and chimerism.

    PubMed

    Kolb, Hans-Jochem; Guenther, Wolfgang; Gyurkocza, Boglarka; Hoetzl, Florian; Simoes, Belinda; Falk, Christine; Schleuning, Michael; Ledderose, Georg

    2003-05-15

    Stem-cell transplantation from human leukocyte antigen (HLA)-haploidentical family members carries a high risk of rejection and graft-versus-host disease (GVHD) if donor and recipient differ by more than one HLA antigen. The authors have developed treatment protocols from studies in dog leukocyte antigen-haploidentical dogs that prevent rejection and modify GVHD to the extent that patients with aggressive hematologic neoplasia can be treated with success. Principal improvements have been achieved in the use of cyclophosphamide and total-body irradiation for conditioning and T-cell depletion for prevention of GVHD. More recently, the combination of marrow and CD6-depleted mobilized donor blood cells (MDBC) has been introduced for HLA-haploidentical transplantation on the basis that CD6-depleted MDBC contain immunoregulatory cells besides stem cells and natural killer cells. Clinical results are reported on 36 patients with high-risk hematologic neoplasia. The results encourage the use of HLA-haploidentical stem-cell transplantation at an earlier stage of the disease. This method could also be of use for tolerance induction in organ transplantation.

  12. Cytotoxicity of Tumor Antigen Specific Human T Cells Is Unimpaired by Arginine Depletion

    PubMed Central

    Knies, Diana; Medenhoff, Sergej; Wabnitz, Guido; Luckner-Minden, Claudia; Feldmeyer, Nadja; Voss, Ralf-Holger; Kropf, Pascale; Müller, Ingrid; Conradi, Roland; Samstag, Yvonne; Theobald, Matthias; Ho, Anthony D.; Goldschmidt, Hartmut; Hundemer, Michael

    2013-01-01

    Tumor-growth is often associated with the expansion of myeloid derived suppressor cells that lead to local or systemic arginine depletion via the enzyme arginase. It is generally assumed that this arginine deficiency induces a global shut-down of T cell activation with ensuing tumor immune escape. While the impact of arginine depletion on polyclonal T cell proliferation and cytokine secretion is well documented, its influence on chemotaxis, cytotoxicity and antigen specific activation of human T cells has not been demonstrated so far. We show here that chemotaxis and early calcium signaling of human T cells are unimpaired in the absence of arginine. We then analyzed CD8+ T cell activation in a tumor peptide as well as a viral peptide antigen specific system: (i) CD8+ T cells with specificity against the MART-1aa26–35*A27L tumor antigen expanded with in vitro generated dendritic cells, and (ii) clonal CMV pp65aa495–503 specific T cells and T cells retrovirally transduced with a CMV pp65aa495–503 specific T cell receptor were analyzed. Our data demonstrate that human CD8+ T cell antigen specific cytotoxicity and perforin secretion are completely preserved in the absence of arginine, while antigen specific proliferation as well as IFN-γ and granzyme B secretion are severely compromised. These novel results highlight the complexity of antigen specific T cell activation and demonstrate that human T cells can preserve important activation-induced effector functions in the context of arginine deficiency. PMID:23717444

  13. Successful haploidentical PBSCT with subsequent T-cell addbacks in a boy with HyperIgM syndrome presenting as severe congenital neutropenia.

    PubMed

    Jasinska, Aleksandra; Kalwak, Krzysztof; Trelinska, Joanna; Borowiec, Maciej; Piatosa, Barbara; Zeman, Krzysztof; Mlynarski, Wojciech

    2013-02-01

    HIGM syndrome is a group of primary immunodeficiency disorders characterized by recurrent bacterial and opportunistic infections; it is also associated with normal to elevated serum IgM levels and a concomitant deficiency of IgG, IgA, and IgE. In this report, we give account of a boy with X-linked HIGM and a novel Y172C mutation within his CD40LG gene. He presented with severe neutropenia as the dominating symptom. His bone marrow showed maturation arrest at the promyelocyte/myelocyte stage, typical of congenital neutropenia. This boy suffered from life-threatening infections and required high doses of rhG-CSF, and a haploidentical PBSCT was also successfully performed, thus leading to reconstitution of CD40L expression on activated CD4+ T cells (as assessed with flow cytometry six months after the procedure). Two low-dose T-cell addbacks were required to re-establish full donor chimerism and clear CMV reactivation. The report demonstrates that in select cases, alternative donor allogeneic HSCT supported by DLI may be effective in correcting the defect in X-linked HIGM, and HSCT in HIGM children is not necessarily limited to matched sibling donor transplantation. © 2012 John Wiley & Sons A/S.

  14. Depletion of Regulatory T Cells Augments a Vaccine-Induced T Effector Cell Response against the Liver-Stage of Malaria but Fails to Increase Memory

    PubMed Central

    Espinoza Mora, Maria del Rosario; Steeg, Christiane; Tartz, Susanne; Heussler, Volker; Sparwasser, Tim; Link, Andreas; Fleischer, Bernhard; Jacobs, Thomas

    2014-01-01

    Regulatory T cells (Treg) have been shown to restrict vaccine-induced T cell responses in different experimental models. In these studies CD4+CD25+ Treg were depleted using monoclonal antibodies against CD25, which might also interfere with CD25 on non-regulatory T cell populations and would have no effect on Foxp3+CD25− Treg. To obtain more insights in the specific function of Treg during vaccination we used mice that are transgenic for a bacterial artificial chromosome expressing a diphtheria toxin (DT) receptor-eGFP fusion protein under the control of the foxp3 gene locus (depletion of regulatory T cell mice; DEREG). As an experimental vaccine-carrier recombinant Bordetella adenylate cyclase toxoid fused with a MHC-class I-restricted epitope of the circumsporozoite protein (ACT-CSP) of Plasmodium berghei (Pb) was used. ACT-CSP was shown by us previously to introduce the CD8+ epitope of Pb-CSP into the MHC class I presentation pathway of professional antigen-presenting cells (APC). Using this system we demonstrate here that the number of CSP-specific T cells increases when Treg are depleted during prime but also during boost immunization. Importantly, despite this increase of T effector cells no difference in the number of antigen-specific memory cells was observed. PMID:25115805

  15. Exacerbation of spontaneous autoimmune nephritis following regulatory T cell depletion in B cell lymphoma 2-interacting mediator knock-out mice.

    PubMed

    Wang, Y M; Zhang, G Y; Wang, Y; Hu, M; Zhou, J J; Sawyer, A; Cao, Q; Wang, Y; Zheng, G; Lee, V W S; Harris, D C H; Alexander, S I

    2017-05-01

    Regulatory T cells (T regs ) have been recognized as central mediators for maintaining peripheral tolerance and limiting autoimmune diseases. The loss of T regs or their function has been associated with exacerbation of autoimmune disease. However, the temporary loss of T regs in the chronic spontaneous disease model has not been investigated. In this study, we evaluated the role of T regs in a novel chronic spontaneous glomerulonephritis model of B cell lymphoma 2-interacting mediator (Bim) knock-out mice by transient depleting T regs . Bim is a pro-apoptotic member of the B cell lymphoma 2 (Bcl-2) family. Bim knock-out (Bim -/- ) mice fail to delete autoreactive T cells in thymus, leading to chronic spontaneous autoimmune kidney disease. We found that T reg depletion in Bim -/- mice exacerbated the kidney injury with increased proteinuria, impaired kidney function, weight loss and greater histological injury compared with wild-type mice. There was a significant increase in interstitial infiltrate of inflammatory cells, antibody deposition and tubular damage. Furthermore, the serum levels of cytokines interleukin (IL)-2, IL-4, IL-6, IL-10, IL-17α, interferon (IFN)-γ and tumour necrosis factor (TNF)-α were increased significantly after T reg depletion in Bim -/- mice. This study demonstrates that transient depletion of T regs leads to enhanced self-reactive T effector cell function followed by exacerbation of kidney disease in the chronic spontaneous kidney disease model of Bim-deficient mice. © 2017 British Society for Immunology.

  16. High risk of graft failure in patients with anti-HLA antibodies undergoing haploidentical stem-cell transplantation.

    PubMed

    Ciurea, Stefan O; de Lima, Marcos; Cano, Pedro; Korbling, Martin; Giralt, Sergio; Shpall, Elizabeth J; Wang, Xuemei; Thall, Peter F; Champlin, Richard E; Fernandez-Vina, Marcelo

    2009-10-27

    BACKGROUND.: Although donor-specific anti-human leukocyte antigen (HLA) antibodies (DSA) have been implicated in graft rejection in solid organ transplantation, their role in hematopoietic stem-cell transplantation remains unclear. METHODS.: To address the hypothesis that the presence of DSA contributes to the development graft failure, we tested 24 consecutive patients for the presence of anti-HLA antibodies determined by a sensitive and specific solid-phase/single-antigen assay. The study included a total of 28 haploidentical transplants, each with 2 to 5 HLA allele mismatches, at a single institution, from September 2005 to August 2008. RESULTS.: DSA were detected in five patients (21%). Three of four (75%) patients with DSA before the first transplant failed to engraft, compared with 1 of 20 (5%) without DSA (P=0.008). All four patients who experienced primary graft failure had second haploidentical transplants. One patient developed a second graft failure with persistent high DSA levels, whereas three engrafted, two of them in the absence of DSA. No other known factors that could negatively influence engraftment were associated with the development of graft failure in these patients. CONCLUSIONS.: These results suggest that donor-specific anti-HLA antibodies are associated with a high rate of graft rejection in patients undergoing haploidentical stem-cell transplantation. Anti-HLA sensitization should be evaluated routinely in hematopoietic stem-cell transplantation with HLA mismatched donors.

  17. Mobilized Peripheral Blood Stem Cells Versus Unstimulated Bone Marrow As a Graft Source for T-Cell-Replete Haploidentical Donor Transplantation Using Post-Transplant Cyclophosphamide.

    PubMed

    Bashey, Asad; Zhang, Mei-Jie; McCurdy, Shannon R; St Martin, Andrew; Argall, Trevor; Anasetti, Claudio; Ciurea, Stefan O; Fasan, Omotayo; Gaballa, Sameh; Hamadani, Mehdi; Munshi, Pashna; Al Malki, Monzr M; Nakamura, Ryotaro; O'Donnell, Paul V; Perales, Miguel-Angel; Raj, Kavita; Romee, Rizwan; Rowley, Scott; Rocha, Vanderson; Salit, Rachel B; Solh, Melhem; Soiffer, Robert J; Fuchs, Ephraim Joseph; Eapen, Mary

    2017-09-10

    Purpose T-cell-replete HLA-haploidentical donor hematopoietic transplantation using post-transplant cyclophosphamide was originally described using bone marrow (BM). With increasing use of mobilized peripheral blood (PB), we compared transplant outcomes after PB and BM transplants. Patients and Methods A total of 681 patients with hematologic malignancy who underwent transplantation in the United States between 2009 and 2014 received BM (n = 481) or PB (n = 190) grafts. Cox regression models were built to examine differences in transplant outcomes by graft type, adjusting for patient, disease, and transplant characteristics. Results Hematopoietic recovery was similar after transplantation of BM and PB (28-day neutrophil recovery, 88% v 93%, P = .07; 100-day platelet recovery, 88% v 85%, P = .33). Risks of grade 2 to 4 acute (hazard ratio [HR], 0.45; P < .001) and chronic (HR, 0.35; P < .001) graft-versus-host disease were lower with transplantation of BM compared with PB. There were no significant differences in overall survival by graft type (HR, 0.99; P = .98), with rates of 54% and 57% at 2 years after transplantation of BM and PB, respectively. There were no differences in nonrelapse mortality risks (HR, 0.92; P = .74) but relapse risks were higher after transplantation of BM (HR, 1.49; P = .009). Additional exploration confirmed that the higher relapse risks after transplantation of BM were limited to patients with leukemia (HR, 1.73; P = .002) and not lymphoma (HR, 0.87; P = .64). Conclusion PB and BM grafts are suitable for haploidentical transplantation with the post-transplant cyclophosphamide approach but with differing patterns of treatment failure. Although, to our knowledge, this is the most comprehensive comparison, these findings must be validated in a randomized prospective comparison with adequate follow-up.

  18. Lineage-specific T-cell reconstitution following in vivo CD4+ and CD8+ lymphocyte depletion in nonhuman primates.

    PubMed

    Engram, Jessica C; Cervasi, Barbara; Borghans, Jose A M; Klatt, Nichole R; Gordon, Shari N; Chahroudi, Ann; Else, James G; Mittler, Robert S; Sodora, Donald L; de Boer, Rob J; Brenchley, Jason M; Silvestri, Guido; Paiardini, Mirko

    2010-08-05

    Many features of T-cell homeostasis in primates are still unclear, thus limiting our understanding of AIDS pathogenesis, in which T-cell homeostasis is lost. Here, we performed experiments of in vivo CD4(+) or CD8(+) lymphocyte depletion in 2 nonhuman primate species, rhesus macaques (RMs) and sooty mangabeys (SMs). Whereas RMs develop AIDS after infection with simian immunodeficiency virus (SIV), SIV-infected SMs are typically AIDS-resistant. We found that, in both species, most CD4(+) or CD8(+) T cells in blood and lymph nodes were depleted after treatment with their respective antibodies. These CD4(+) and CD8(+) lymphocyte depletions were followed by a largely lineage-specific CD4(+) and CD8(+) T-cell proliferation, involving mainly memory T cells, which correlated with interleukin-7 plasma levels. Interestingly, SMs showed a faster repopulation of naive CD4(+) T cells than RMs. In addition, in both species CD8(+) T-cell repopulation was faster than that of CD4(+) T cells, with CD8(+) T cells reconstituting a normal pool within 60 days and CD4(+) T cells remaining below baseline levels up to day 180 after depletion. While this study revealed subtle differences in CD4(+) T-cell repopulation in an AIDS-sensitive versus an AIDS-resistant species, such differences may have particular relevance in the presence of active SIV repli cation, where CD4(+) T-cell destruction is chronic.

  19. Lineage-specific T-cell reconstitution following in vivo CD4+ and CD8+ lymphocyte depletion in nonhuman primates

    PubMed Central

    Engram, Jessica C.; Cervasi, Barbara; Borghans, Jose A. M.; Klatt, Nichole R.; Gordon, Shari N.; Chahroudi, Ann; Else, James G.; Mittler, Robert S.; Sodora, Donald L.; de Boer, Rob J.; Brenchley, Jason M.; Silvestri, Guido

    2010-01-01

    Many features of T-cell homeostasis in primates are still unclear, thus limiting our understanding of AIDS pathogenesis, in which T-cell homeostasis is lost. Here, we performed experiments of in vivo CD4+ or CD8+ lymphocyte depletion in 2 nonhuman primate species, rhesus macaques (RMs) and sooty mangabeys (SMs). Whereas RMs develop AIDS after infection with simian immunodeficiency virus (SIV), SIV-infected SMs are typically AIDS-resistant. We found that, in both species, most CD4+ or CD8+ T cells in blood and lymph nodes were depleted after treatment with their respective antibodies. These CD4+ and CD8+ lymphocyte depletions were followed by a largely lineage-specific CD4+ and CD8+ T-cell proliferation, involving mainly memory T cells, which correlated with interleukin-7 plasma levels. Interestingly, SMs showed a faster repopulation of naive CD4+ T cells than RMs. In addition, in both species CD8+ T-cell repopulation was faster than that of CD4+ T cells, with CD8+ T cells reconstituting a normal pool within 60 days and CD4+ T cells remaining below baseline levels up to day 180 after depletion. While this study revealed subtle differences in CD4+ T-cell repopulation in an AIDS-sensitive versus an AIDS-resistant species, such differences may have particular relevance in the presence of active SIV repli cation, where CD4+ T-cell destruction is chronic. PMID:20484087

  20. Depletion of CD4+ T cells abrogates post-peak decline of viremia in SIV-infected rhesus macaques

    PubMed Central

    Ortiz, Alexandra M.; Klatt, Nichole R.; Li, Bing; Yi, Yanjie; Tabb, Brian; Hao, Xing Pei; Sternberg, Lawrence; Lawson, Benton; Carnathan, Paul M.; Cramer, Elizabeth M.; Engram, Jessica C.; Little, Dawn M.; Ryzhova, Elena; Gonzalez-Scarano, Francisco; Paiardini, Mirko; Ansari, Aftab A.; Ratcliffe, Sarah; Else, James G.; Brenchley, Jason M.; Collman, Ronald G.; Estes, Jacob D.; Derdeyn, Cynthia A.; Silvestri, Guido

    2011-01-01

    CD4+ T cells play a central role in the immunopathogenesis of HIV/AIDS, and their depletion during chronic HIV infection is a hallmark of disease progression. However, the relative contribution of CD4+ T cells as mediators of antiviral immune responses and targets for virus replication is still unclear. Here, we have generated data in SIV-infected rhesus macaques (RMs) that suggest that CD4+ T cells are essential in establishing control of virus replication during acute infection. To directly assess the role of CD4+ T cells during primary SIV infection, we in vivo depleted these cells from RMs prior to infecting the primates with a pathogenic strain of SIV. Compared with undepleted animals, CD4+ lymphocyte–depleted RMs showed a similar peak of viremia, but did not manifest any post-peak decline of virus replication despite CD8+ T cell– and B cell–mediated SIV-specific immune responses comparable to those observed in control animals. Interestingly, depleted animals displayed rapid disease progression, which was associated with increased virus replication in non-T cells as well as the emergence of CD4-independent SIV-envelopes. Our results suggest that the antiviral CD4+ T cell response may play an important role in limiting SIV replication, which has implications for the design of HIV vaccines. PMID:22005304

  1. Apoptotic depletion of CD4+ T cells in idiopathic CD4+ T lymphocytopenia.

    PubMed Central

    Laurence, J; Mitra, D; Steiner, M; Lynch, D H; Siegal, F P; Staiano-Coico, L

    1996-01-01

    Progressive loss of CD4+ T lymphocytes, accompanied by opportunistic infections characteristic of the acquired immune deficiency syndrome, ahs been reported in the absence of any known etiology. The pathogenesis of this syndrome, a subset of idiopathic CD4+ T lymphocytopenia (ICL), is uncertain. We report that CD4+ T cells from seven of eight ICL patients underwent accelerated programmed cell death, a process facilitated by T cell receptor cross-linking. Apoptosis was associated with enhanced expression of Fas and Fas ligand in unstimulated cell populations, and partially inhibited by soluble anti-Fas mAb. In addition, apoptosis was suppressed by aurintricarboxylic acid, an inhibitor of calcium-dependent endonucleases and proteases, in cells from four of seven patients, The in vivo significance of these findings was supported by three factors: the absence of accelerated apoptosis in persons with stable, physiologic CD4 lymphopenia without clinical immune deficiency; detection of serum antihistone H2B autoantibodies, one consequence of DNA fragmentation, in some patients; and its selectivity, with apoptosis limited to the CD4 population in some, and occurring among CD8+ T cells predominantly in those individuals with marked depletion of both CD4+ T lymphocytes linked to clinical immune suppression have evidence for accelerated T cell apoptosis in vitro that may be pathophysiologic and amenable to therapy with apoptosis inhibitors. PMID:8609222

  2. Chorion Mesenchymal Stem Cells Show Superior Differentiation, Immunosuppressive, and Angiogenic Potentials in Comparison With Haploidentical Maternal Placental Cells

    PubMed Central

    González, Paz L.; Carvajal, Catalina; Cuenca, Jimena; Alcayaga-Miranda, Francisca; Figueroa, Fernando E.; Bartolucci, Jorge; Salazar-Aravena, Lorena

    2015-01-01

    Mesenchymal stem cells (MSCs) of placental origin have become increasingly translational owing to their abundance and accessibility. MSCs of different origin share several features but also present biological differences that might point to distinct clinical properties. Hence, mixing fetal and maternal cells from the same placenta can lead to contradicting results. We analyzed the biological characteristics of haploidentical MSCs isolated from fetal sources, including the umbilical cord (UC-MSCs) and chorion (Ch-MSCs), compared with maternal decidua MSCs (Dc-MSCs). All MSCs were analyzed for general stem cell properties. In addition, immunosuppressive capacity was assessed by the inhibition of T-cell proliferation, and angiogenic potential was evaluated in a Matrigel transplantation assay. The comparison between haploidentical MSCs displayed several distinct features, including (a) marked differences in the expression of CD56, (b) a higher proliferative capacity for Dc-MSCs and UC-MSCs than for Ch-MSCs, (c) a diversity of mesodermal differentiation potential in favor of fetal MSCs, (d) a higher capacity for Ch-MSCs to inhibit T-cell proliferation, and (e) superior angiogenic potential of Ch-MSCs evidenced by a higher capability to form tubular vessel-like structures and an enhanced release of hepatocyte growth factor and vascular endothelial growth factor under hypoxic conditions. Our results suggest that assessing the prevalence of fetomaternal contamination within placental MSCs is necessary to increase robustness and limit side effects in their clinical use. Finally, our work presents evidence positioning fetoplacental cells and notably Ch-MSCs in the forefront of the quest for cell types that are superior for applications in regenerative medicine. Significance This study analyzed the biological characteristics of mesenchymal stem cells (MSCs) isolated from fetal and maternal placental origins. The findings can be summarized as follows: (a) important differences

  3. Administration of herpes simplex-thymidine kinase-expressing donor T cells with a T-cell-depleted allogeneic marrow graft.

    PubMed

    Tiberghien, P; Ferrand, C; Lioure, B; Milpied, N; Angonin, R; Deconinck, E; Certoux, J M; Robinet, E; Saas, P; Petracca, B; Juttner, C; Reynolds, C W; Longo, D L; Hervé, P; Cahn, J Y

    2001-01-01

    Administration of donor T cells expressing the herpes simplex-thymidine kinase (HS-tk) with a hematopoietic stem cell (HSC) transplantation could allow, if graft-versus-host disease (GVHD) was to occur, a selective in vivo depletion of these T cells by the use of ganciclovir (GCV). The study evaluates the feasibility of such an approach. Escalating numbers of donor HS-tk-expressing CD3(+) gene-modified cells (GMCs) are infused with a T-cell-depleted bone marrow transplantation (BMT). Twelve patients with hematological malignancies received 2 x 10(5) (n = 5), 6 x 10(5) (n = 5), or 20 x 10(5) (n = 2) donor CD3(+) GMCs/kg with a BMT from a human leukocyte antigen (HLA)-identical sibling. No acute toxicity was associated with GMC administration. An early increase of circulating GMCs followed by a progressive decrease and long-lasting circulation of GMCs was documented. GCV treatment resulted in significant rapid decrease in circulating GMCs. Three patients developed acute GVHD, with a grade of at least II, while one patient developed chronic GVHD. Treatment with GCV alone was associated with a complete remission (CR) in 2 patients with acute GVHD, while the addition of glucocorticoids was necessary to achieve a CR in the last case. Long-lasting CR occurred with GCV treatment in the patient with chronic GVHD. Unfortunately, Epstein-Barr virus-lymphoproliferative disease occurred in 3 patients. Overall, the administration of low numbers of HS-tk-expressing T cells early following an HLA-identical BMT is associated with no acute toxicity, persistent circulation of the GMCs, and GCV-sensitive GVHD. Such findings open the way to the infusion of higher numbers of gene-modified donor T cells to enhance post-BMT immune competence while preserving GCV-sensitive alloreactivity.

  4. Pyroptosis drives CD4 T-cell depletion in HIV-1 infection

    PubMed Central

    Doitsh, Gilad; Galloway, Nicole LK; Geng, Xin; Yang, Zhiyuan; Monroe, Kathryn M.; Zepeda, Orlando; Hunt, Peter W.; Hatano, Hiroyu; Sowinski, Stefanie; Muñoz-Arias, Isa; Greene, Warner C.

    2014-01-01

    The pathway causing CD4 T-cell death in HIV-infected hosts remains poorly understood. Apoptosis has been proposed as the key mechanism for CD4 T-cell loss. We now show that caspase-3-mediated apoptosis accounts for the death of only a small fraction of productively infected cells. The remaining >95% of quiescent lymphoid CD4 T-cells die by caspase-1-mediated pyroptosis triggered by abortive viral infection. Pyroptosis corresponds to an intensely inflammatory form of programmed cell death where cytoplasmic contents and pro-inflammatory cytokines including IL-1β, are released. This death pathway thus links the two signature events in HIV infection––CD4 T-cell depletion and chronic inflammation––and creates a vicious pathogenic cycle where dying CD4 T-cells release inflammatory signals that attract more cells to die. This cycle can be broken by caspase-1 inhibitors shown to be safe in humans, raising the possibility of a new class of “anti-AIDS” therapeutics targeting the host rather than the virus. PMID:24356306

  5. Donor-derived CD19-targeted T cell infusion induces minimal residual disease-negative remission in relapsed B-cell acute lymphoblastic leukaemia with no response to donor lymphocyte infusions after haploidentical haematopoietic stem cell transplantation.

    PubMed

    Chen, Yuhong; Cheng, Yifei; Suo, Pan; Yan, Chenhua; Wang, Yu; Chen, Yao; Han, Wei; Xu, Lanping; Zhang, Xiaohui; Liu, Kaiyan; Chang, Lungji; Xiao, Lei; Huang, Xiaojun

    2017-11-01

    Relapse is a common cause of failure in patients with B-cell acute lymphoblastic leukaemia (B-ALL) after haploidentical haematopoietic stem cell transplantation (haplo-HSCT), and non-responders to donor lymphoblastic infusion after HSCT have a very poor prognosis. Although donor-derived CD19-directed chimeric antigen receptor-modified (CAR) T cells can potentially cure leukaemia, their effectiveness and safety have not been confirmed in relapsed B-ALL cases after haplo-HSCT. Between January 2015 and January 2017, two and four patients each received one and two infusions of CAR T cells from haplo-HSCT donors. Five (83·33%) achieved minimal residual disease (MRD)-negative remission; one patient was discharged automatically without evaluation after developing severe thrombotic microangiopathies. Four of five responsive patients relapsed after 2-7 months, and one died of sepsis following MRD-negative remission after a second infusion. None of the other second infusion recipients achieved a second complete remission. Five patients (83·33%) experienced eight courses of grade 1-3 cytokine release syndrome; two were treated with tocilizumab. Two (33·3%) and one patient developed grade 2 and 3 acute graft-versus-host disease (aGVHD), respectively; the former was controlled with glucocorticoids. Donor-derived CAR T-cell infusion seems be effective and safe for relapsed B-ALL after haplo-HSCT, although larger clinical studies are needed. © 2017 John Wiley & Sons Ltd.

  6. Increased loss of CCR5+ CD45RA- CD4+ T cells in CD8+ lymphocyte-depleted Simian immunodeficiency virus-infected rhesus monkeys.

    PubMed

    Veazey, Ronald S; Acierno, Paula M; McEvers, Kimberly J; Baumeister, Susanne H C; Foster, Gabriel J; Rett, Melisa D; Newberg, Michael H; Kuroda, Marcelo J; Williams, Kenneth; Kim, Eun-Young; Wolinsky, Steven M; Rieber, E Peter; Piatak, Michael; Lifson, Jeffrey D; Montefiori, David C; Brown, Charles R; Hirsch, Vanessa M; Schmitz, Jörn E

    2008-06-01

    Previously we have shown that CD8(+) T cells are critical for containment of simian immunodeficiency virus (SIV) viremia and that rapid and profound depletion of CD4(+) T cells occurs in the intestinal tract of acutely infected macaques. To determine the impact of SIV-specific CD8(+) T-cell responses on the magnitude of the CD4(+) T-cell depletion, we investigated the effect of CD8(+) lymphocyte depletion during primary SIV infection on CD4(+) T-cell subsets and function in peripheral blood, lymph nodes, and intestinal tissues. In peripheral blood, CD8(+) lymphocyte-depletion changed the dynamics of CD4(+) T-cell loss, resulting in a more pronounced loss 2 weeks after infection, followed by a temporal rebound approximately 2 months after infection, when absolute numbers of CD4(+) T cells were restored to baseline levels. These CD4(+) T cells showed a markedly skewed phenotype, however, as there were decreased levels of memory cells in CD8(+) lymphocyte-depleted macaques compared to controls. In intestinal tissues and lymph nodes, we observed a significantly higher loss of CCR5(+) CD45RA(-) CD4(+) T cells in CD8(+) lymphocyte-depleted macaques than in controls, suggesting that these SIV-targeted CD4(+) T cells were eliminated more efficiently in CD8(+) lymphocyte-depleted animals. Also, CD8(+) lymphocyte depletion significantly affected the ability to generate SIV Gag-specific CD4(+) T-cell responses and neutralizing antibodies. These results reemphasize that SIV-specific CD8(+) T-cell responses are absolutely critical to initiate at least partial control of SIV infection.

  7. Optimized depletion of chimeric antigen receptor T cells in murine xenograft models of human acute myeloid leukemia

    PubMed Central

    Kenderian, Saad S.; Shen, Feng; Ruella, Marco; Shestova, Olga; Kozlowski, Miroslaw; Li, Yong; Schrank-Hacker, April; Morrissette, Jennifer J. D.; Carroll, Martin; June, Carl H.; Grupp, Stephan A.; Gill, Saar

    2017-01-01

    We and others previously reported potent antileukemia efficacy of CD123-redirected chimeric antigen receptor (CAR) T cells in preclinical human acute myeloid leukemia (AML) models at the cost of severe hematologic toxicity. This observation raises concern for potential myeloablation in patients with AML treated with CD123-redirected CAR T cells and mandates novel approaches for toxicity mitigation. We hypothesized that CAR T-cell depletion with optimal timing after AML eradication would preserve leukemia remission and allow subsequent hematopoietic stem cell transplantation. To test this hypothesis, we compared 3 CAR T-cell termination strategies: (1) transiently active anti-CD123 messenger RNA–electroporated CART (RNA-CART123); (2) T-cell ablation with alemtuzumab after treatment with lentivirally transduced anti–CD123-4-1BB-CD3ζ T cells (CART123); and (3) T-cell ablation with rituximab after treatment with CD20-coexpressing CART123 (CART123-CD20). All approaches led to rapid leukemia elimination in murine xenograft models of human AML. Subsequent antibody-mediated depletion of CART123 or CART123-CD20 did not impair leukemia remission. Time-course studies demonstrated that durable leukemia remission required CAR T-cell persistence for 4 weeks prior to ablation. Upon CAR T-cell termination, we further demonstrated successful hematopoietic engraftment with a normal human donor to model allogeneic stem cell rescue. Results from these studies will facilitate development of T-cell depletion strategies to augment the feasibility of CAR T-cell therapy for patients with AML. PMID:28246194

  8. B cell depleting therapy regulates splenic and circulating T follicular helper cells in immune thrombocytopenia.

    PubMed

    Audia, Sylvain; Rossato, Marzia; Trad, Malika; Samson, Maxime; Santegoets, Kim; Gautheron, Alexandrine; Bekker, Cornelis; Facy, Olivier; Cheynel, Nicolas; Ortega-Deballon, Pablo; Boulin, Mathieu; Berthier, Sabine; Leguy-Seguin, Vanessa; Martin, Laurent; Ciudad, Marion; Janikashvili, Nona; Saas, Philippe; Radstake, Timothy; Bonnotte, Bernard

    2017-02-01

    B cells are involved in immune thrombocytopenia (ITP) pathophysiology by producing antiplatelet auto-antibodies. However more than a half of ITP patients do not respond to B cell depletion induced by rituximab (RTX). The persistence of splenic T follicular helper cells (TFH) that we demonstrated to be expanded during ITP and to support B cell differentiation and antiplatelet antibody-production may participate to RTX inefficiency. Whereas it is well established that the survival of TFH depends on B cells in animal models, nothing is known in humans yet. To determine the effect of B cell depletion on human TFH, we quantified B cells and TFH in the spleen and in the blood from ITP patients treated or not with RTX. We showed that B cell depletion led to a dramatic decrease in splenic TFH and in CXCL13 and IL-21, two cytokines predominantly produced by TFH. The absolute count of circulating TFH and serum CXCL13 also decreased after RTX treatment, whatever the therapeutic response. Therefore, we showed that the maintenance of TFH required B cells and that TFH are not involved in the inefficiency of RTX in ITP. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Cell death by pyroptosis drives CD4 T-cell depletion in HIV-1 infection

    NASA Astrophysics Data System (ADS)

    Doitsh, Gilad; Galloway, Nicole L. K.; Geng, Xin; Yang, Zhiyuan; Monroe, Kathryn M.; Zepeda, Orlando; Hunt, Peter W.; Hatano, Hiroyu; Sowinski, Stefanie; Muñoz-Arias, Isa; Greene, Warner C.

    2014-01-01

    The pathway causing CD4 T-cell death in HIV-infected hosts remains poorly understood although apoptosis has been proposed as a key mechanism. We now show that caspase-3-mediated apoptosis accounts for the death of only a small fraction of CD4 T cells corresponding to those that are both activated and productively infected. The remaining over 95% of quiescent lymphoid CD4 T cells die by caspase-1-mediated pyroptosis triggered by abortive viral infection. Pyroptosis corresponds to an intensely inflammatory form of programmed cell death in which cytoplasmic contents and pro-inflammatory cytokines, including IL-1β, are released. This death pathway thus links the two signature events in HIV infection--CD4 T-cell depletion and chronic inflammation--and creates a pathogenic vicious cycle in which dying CD4 T cells release inflammatory signals that attract more cells to die. This cycle can be broken by caspase 1 inhibitors shown to be safe in humans, raising the possibility of a new class of `anti-AIDS' therapeutics targeting the host rather than the virus.

  10. Severe depletion of mucosal CD4+ T cells in AIDS-free simian immunodeficiency virus-infected sooty mangabeys.

    PubMed

    Gordon, Shari N; Klatt, Nichole R; Bosinger, Steven E; Brenchley, Jason M; Milush, Jeffrey M; Engram, Jessica C; Dunham, Richard M; Paiardini, Mirko; Klucking, Sara; Danesh, Ali; Strobert, Elizabeth A; Apetrei, Cristian; Pandrea, Ivona V; Kelvin, David; Douek, Daniel C; Staprans, Silvija I; Sodora, Donald L; Silvestri, Guido

    2007-09-01

    HIV-infected humans and SIV-infected rhesus macaques experience a rapid and dramatic loss of mucosal CD4+ T cells that is considered to be a key determinant of AIDS pathogenesis. In this study, we show that nonpathogenic SIV infection of sooty mangabeys (SMs), a natural host species for SIV, is also associated with an early, severe, and persistent depletion of memory CD4+ T cells from the intestinal and respiratory mucosa. Importantly, the kinetics of the loss of mucosal CD4+ T cells in SMs is similar to that of SIVmac239-infected rhesus macaques. Although the nonpathogenic SIV infection of SMs induces the same pattern of mucosal target cell depletion observed during pathogenic HIV/SIV infections, the depletion in SMs occurs in the context of limited local and systemic immune activation and can be reverted if virus replication is suppressed by antiretroviral treatment. These results indicate that a profound depletion of mucosal CD4+ T cells is not sufficient per se to induce loss of mucosal immunity and disease progression during a primate lentiviral infection. We propose that, in the disease-resistant SIV-infected SMs, evolutionary adaptation to both preserve immune function with fewer mucosal CD4+ T cells and attenuate the immune activation that follows acute viral infection protect these animals from progressing to AIDS.

  11. Fever after peripheral blood stem cell infusion in haploidentical transplantation with post-transplant cyclophosphamide.

    PubMed

    Arango, Marcos; Combariza, Juan F

    2017-06-01

    Noninfection-related fever can occur after peripheral blood stem cell infusion in haploidentical hematopoietic stem cell transplantation with post-transplant cyclophosphamide. The objective of this study was to analyze the incidence of fever and characterize some clinical features of affected patients. A retrospective case-series study with 40 patients who received haploidentical hematopoietic stem cell transplantation was carried out. Thirty-three patients (82.5%) developed fever; no baseline characteristic was associated with its development. Median time to fever onset was 25.5h (range, 9.5-100h) and median peak temperature was 39.0°C (range, 38.1-40.5°C). Not a single patient developed hemodynamic or respiratory compromise that required admission to the intensive care unit. Fever was not explained by infection in any case. Ninety-one percent of the febrile episodes resolved within 96h of cyclophosphamide administration. No significant difference in overall survival, event-free survival, or graft versus host disease-free/relapse-free survival was found in the group of febrile individuals after peripheral blood stem cell infusion. Fever after peripheral blood stem cell infusion in this clinical setting was common; it usually subsides with cyclophosphamide administration. The development of fever was not associated with an adverse prognosis. Copyright © 2017 King Faisal Specialist Hospital & Research Centre. Published by Elsevier B.V. All rights reserved.

  12. Late Graft Rejection in Association With T-Large Granular Lymphocyte Expansion of Recipient Origin After Human Leukocyte Antigen-Haploidentical Stem Cell Transplantation: A Case Report.

    PubMed

    Nakagawa, N; Yamazaki, H; Aoki, G; Kondo, Y; Nakao, S

    2016-11-01

    Large granular lymphocyte (LGL) expansion occasionally occurs after allogeneic stem cell transplantation (allo-SCT), and is thought to be a good prognostic sign that is associated with a lower relapse rate. However, there have been no reports of late graft failure (LGF) due to graft rejection in association with oligoclonal LGL expansion. We herein report a case of LGF associated with the transient expansion of recipient-derived T-LGL after allo-SCT. A 65-year-old man underwent peripheral blood stem cell transplantation (PBSCT) from his human leukocyte antigen (HLA)-haploidentical son for the treatment of acute myeloid leukemia, which had evolved from a myelodysplastic syndrome (MDS). Neutrophil engraftment occurred on day 20. A chimerism analysis on day 29 showed both granulocytes and mononuclear cells in the peripheral blood to be completely of donor origin. However, his neutrophil count gradually decreased and a chimerism analysis on day 61 showed that 84% of the patient's T cells were of recipient origin while the granulocytes were 100% donor-derived. His LGLs rapidly increased to 4.01 × 10 9 /L on day 113 and decreased thereafter. The percentage of donor cells in his granulocytes gradually decreased, and the patient's leukocytes were completely replaced by recipient cells on day 177. The clinical course suggests that the expansion of recipient-derived T-LGLs after allo-SCT can be a sign of graft rejection. Early intervention may be needed if the LGL expansion is recipient-derived. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Depletion of CD4⁺ T cells abrogates post-peak decline of viremia in SIV-infected rhesus macaques.

    PubMed

    Ortiz, Alexandra M; Klatt, Nichole R; Li, Bing; Yi, Yanjie; Tabb, Brian; Hao, Xing Pei; Sternberg, Lawrence; Lawson, Benton; Carnathan, Paul M; Cramer, Elizabeth M; Engram, Jessica C; Little, Dawn M; Ryzhova, Elena; Gonzalez-Scarano, Francisco; Paiardini, Mirko; Ansari, Aftab A; Ratcliffe, Sarah; Else, James G; Brenchley, Jason M; Collman, Ronald G; Estes, Jacob D; Derdeyn, Cynthia A; Silvestri, Guido

    2011-11-01

    CD4+ T cells play a central role in the immunopathogenesis of HIV/AIDS, and their depletion during chronic HIV infection is a hallmark of disease progression. However, the relative contribution of CD4+ T cells as mediators of antiviral immune responses and targets for virus replication is still unclear. Here, we have generated data in SIV-infected rhesus macaques (RMs) that suggest that CD4+ T cells are essential in establishing control of virus replication during acute infection. To directly assess the role of CD4+ T cells during primary SIV infection, we in vivo depleted these cells from RMs prior to infecting the primates with a pathogenic strain of SIV. Compared with undepleted animals, CD4+ lymphocyte-depleted RMs showed a similar peak of viremia, but did not manifest any post-peak decline of virus replication despite CD8+ T cell- and B cell-mediated SIV-specific immune responses comparable to those observed in control animals. Interestingly, depleted animals displayed rapid disease progression, which was associated with increased virus replication in non-T cells as well as the emergence of CD4-independent SIV-envelopes. Our results suggest that the antiviral CD4+ T cell response may play an important role in limiting SIV replication, which has implications for the design of HIV vaccines.

  14. Severe Depletion of Mucosal CD4+ T Cells in AIDS-Free Simian Immunodeficiency Virus-Infected Sooty Mangabeys1

    PubMed Central

    Gordon, Shari N.; Klatt, Nichole R.; Bosinger, Steven E.; Brenchley, Jason M.; Milush, Jeffrey M.; Engram, Jessica C.; Dunham, Richard M.; Paiardini, Mirko; Klucking, Sara; Danesh, Ali; Strobert, Elizabeth A.; Apetrei, Cristian; Pandrea, Ivona V.; Kelvin, David; Douek, Daniel C.; Staprans, Silvija I.; Sodora, Donald L.; Silvestri, Guido

    2008-01-01

    HIV-infected humans and SIV-infected rhesus macaques experience a rapid and dramatic loss of mucosal CD4+ T cells that is considered to be a key determinant of AIDS pathogenesis. In this study, we show that nonpathogenic SIV infection of sooty mangabeys (SMs), a natural host species for SIV, is also associated with an early, severe, and persistent depletion of memory CD4+ T cells from the intestinal and respiratory mucosa. Importantly, the kinetics of the loss of mucosal CD4+ T cells in SMs is similar to that of SIVmac239-infected rhesus macaques. Although the nonpathogenic SIV infection of SMs induces the same pattern of mucosal target cell depletion observed during pathogenic HIV/SIV infections, the depletion in SMs occurs in the context of limited local and systemic immune activation and can be reverted if virus replication is suppressed by antiretroviral treatment. These results indicate that a profound depletion of mucosal CD4+ T cells is not sufficient per se to induce loss of mucosal immunity and disease progression during a primate lentiviral infection. We propose that, in the disease-resistant SIV-infected SMs, evolutionary adaptation to both preserve immune function with fewer mucosal CD4+ T cells and attenuate the immune activation that follows acute viral infection protect these animals from progressing to AIDS. PMID:17709517

  15. Fc-dependent depletion of tumor-infiltrating regulatory T cells co-defines the efficacy of anti–CTLA-4 therapy against melanoma

    PubMed Central

    Simpson, Tyler R.; Li, Fubin; Montalvo-Ortiz, Welby; Sepulveda, Manuel A.; Bergerhoff, Katharina; Arce, Frederick; Roddie, Claire; Henry, Jake Y.; Yagita, Hideo; Wolchok, Jedd D.; Peggs, Karl S.; Ravetch, Jeffrey V.

    2013-01-01

    Treatment with monoclonal antibody specific for cytotoxic T lymphocyte–associated antigen 4 (CTLA-4), an inhibitory receptor expressed by T lymphocytes, has emerged as an effective therapy for the treatment of metastatic melanoma. Although subject to debate, current models favor a mechanism of activity involving blockade of the inhibitory activity of CTLA-4 on both effector (T eff) and regulatory (T reg) T cells, resulting in enhanced antitumor effector T cell activity capable of inducing tumor regression. We demonstrate, however, that the activity of anti–CTLA-4 antibody on the T reg cell compartment is mediated via selective depletion of T reg cells within tumor lesions. Importantly, T reg cell depletion is dependent on the presence of Fcγ receptor–expressing macrophages within the tumor microenvironment, indicating that T reg cells are depleted in trans in a context-dependent manner. Our results reveal further mechanistic insight into the activity of anti-CTLA-4–based cancer immunotherapy, and illustrate the importance of specific features of the local tumor environment on the final outcome of antibody-based immunomodulatory therapies. PMID:23897981

  16. [Outcome of haploidentical hematopoietic stem cell transplantation for non-Hodgkin lymphoma].

    PubMed

    Xu, T; Chen, J; Jin, Z M; Miao, M; Fu, C C; Qiu, H Y; Tang, X W; Han, Y; Sun, A N; Wu, D P

    2016-08-14

    To explore the efficacy and safety of haploidentical hematopoietic stem cell transplantation (Haplo- HSCT) for refractory, relapsed or highly aggressive non- Hodgkin lymphoma (NHL) patients. A total of 26 patients with refractory, relapsed or highly aggressive NHL who received Haplo- HSCT from Jan. 2004 to Mar. 2015 were analyzed retrospectively. Of them, 4 patients had diffuse large B-cell lymphoma (DLBCL), 1 had follicular lymphoma, 5 had B-lymphoblastic lymphoma/leukemia, 9 had T- lymphoblastic lymphoma/leukemia, 1 patient anaplastic large cell lymphoma (ALK-negative), 5 had peripheral T-cell lymphoma (NOS), and 1 had NK/T-cell lymphoma. At the time of initial diagnosis, 6 patients had Ann Arbor stage Ⅲ disease, 20 patients showed stage Ⅳ. At the time of Haplo- HSCT, 7 patients were in the first complete remission (CR1), 4 in the second complete remission (CR2), 7 in partial remission, 1 in stable disease, 7 in progressive disease, and 19 of 26 patients were refractory or relapsed. The neutrophil and platelet counts recovered at 12 (11-17) d and 14 (11-31) d after Haplo- HSCT, respectively. All patients achieved full donor chimerism at 30d after Haplo- HSCT. With a median follow- up of 14 (4- 136) months, 20 cases (76.92%) survived, 15 (57.69%) survived without lymphoma, and 7 (26.92%) relapsed. Conditioning regimen related adverse reactions were all disappeared after treatment. The estimated 2-year recurrence rate after Haplo-HSCT was 42.20%. The estimated 2-year overall survival (OS) and disease-free survival (DFS) rate was 71.60% and 48.90%, respectively. Patients in CR before Haplo- HSCT experienced better 2- year OS (100.0% vs 52.4%, P=0.023) and 2- year DFS (88.9% vs 27.0%, P=0.013). Haplo- HSCT may effective and safe for those relapsed, refractory or highly aggressive NHL patients who did not have matched donor nor suitable for autologous HSCT.

  17. Targeted antibody-mediated depletion of murine CD19 CAR T cells permanently reverses B cell aplasia

    PubMed Central

    Paszkiewicz, Paulina J.; Fräßle, Simon P.; Srivastava, Shivani; Sommermeyer, Daniel; Hudecek, Michael; Sadelain, Michel; Liu, Lingfeng; Jensen, Michael C.; Riddell, Stanley R.; Busch, Dirk H.

    2016-01-01

    The adoptive transfer of T cells that have been genetically modified to express a CD19-specific chimeric antigen receptor (CAR) is effective for treating human B cell malignancies. However, the persistence of functional CD19 CAR T cells causes sustained depletion of endogenous CD19+ B cells and hypogammaglobulinemia. Thus, there is a need for a mechanism to ablate transferred T cells after tumor eradication is complete to allow recovery of normal B cells. Previously, we developed a truncated version of the epidermal growth factor receptor (EGFRt) that is coexpressed with the CAR on the T cell surface. Here, we show that targeting EGFRt with the IgG1 monoclonal antibody cetuximab eliminates CD19 CAR T cells both early and late after adoptive transfer in mice, resulting in complete and permanent recovery of normal functional B cells, without tumor relapse. EGFRt can be incorporated into many clinical applications to regulate the survival of gene-engineered cells. These results support the concept that EGFRt represents a promising approach to improve safety of cell-based therapies. PMID:27760047

  18. Targeted antibody-mediated depletion of murine CD19 CAR T cells permanently reverses B cell aplasia.

    PubMed

    Paszkiewicz, Paulina J; Fräßle, Simon P; Srivastava, Shivani; Sommermeyer, Daniel; Hudecek, Michael; Drexler, Ingo; Sadelain, Michel; Liu, Lingfeng; Jensen, Michael C; Riddell, Stanley R; Busch, Dirk H

    2016-11-01

    The adoptive transfer of T cells that have been genetically modified to express a CD19-specific chimeric antigen receptor (CAR) is effective for treating human B cell malignancies. However, the persistence of functional CD19 CAR T cells causes sustained depletion of endogenous CD19+ B cells and hypogammaglobulinemia. Thus, there is a need for a mechanism to ablate transferred T cells after tumor eradication is complete to allow recovery of normal B cells. Previously, we developed a truncated version of the epidermal growth factor receptor (EGFRt) that is coexpressed with the CAR on the T cell surface. Here, we show that targeting EGFRt with the IgG1 monoclonal antibody cetuximab eliminates CD19 CAR T cells both early and late after adoptive transfer in mice, resulting in complete and permanent recovery of normal functional B cells, without tumor relapse. EGFRt can be incorporated into many clinical applications to regulate the survival of gene-engineered cells. These results support the concept that EGFRt represents a promising approach to improve safety of cell-based therapies.

  19. Role of immune activation in CD4+ T-cell depletion in HIV-1 infected Indian patients.

    PubMed

    Vajpayee, M; Kaushik, S; Sreenivas, V; Mojumdar, K; Mendiratta, S; Chauhan, N K

    2009-01-01

    The correlation of immune activation with CD4(+) depletion and HIV-1 disease progression has been evidenced by several studies involving mainly clade B virus. However, this needs to be investigated in developing countries such as India predominately infected with clade C virus. In a cross-sectional study of 68 antiretroviral treatment naïve, HIV-1 infected Indian patients, we studied the association between CD4(+) T cells, plasma HIV-1 RNA levels, and immune activation markers using unadjusted and adjusted correlative analyses. Significant negative correlations of higher magnitude were observed between the CD4(+) T cell percentages and plasma HIV-1 RNA levels in the study population when adjusted for the effects of immune activation markers. However, the negative association of CD4(+) T cells with immune activation markers remained unaffected when controlled for the effects of plasma HIV-1 RNA levels. Our results support the important role of immune activation in CD4(+) T cell depletion and disease progression during untreated HIV-1 infection.

  20. The European Society for Blood and Marrow Transplantation (EBMT) Consensus Guidelines for the Detection and Treatment of Donor-specific Anti-HLA Antibodies (DSA) in Haploidentical Hematopoietic Cell Transplantation.

    PubMed

    Ciurea, Stefan O; Cao, Kai; Fernadez-Vina, Marcelo; Kongtim, Piyanuch; Malki, Monzr Al; Fuchs, Ephraim; Luznik, Leo; Huang, Xiao-Jun; Ciceri, Fabio; Locatelli, Franco; Aversa, Franco; Castagna, Luca; Bacigalupo, Andrea; Martelli, Massimo; Blaise, Didier; Handgretinger, Rupert; Roy, Denis-Claude; O'Donnell, Paul; Bashey, Asad; Lazarus, Hillard M; Ballen, Karen; Savani, Bipin N; Mohty, Mohamad; Nagler, Arnon

    2018-05-01

    Haploidentical donors are now increasingly considered for transplantation in the absence of HLA-matched donors or when an urgent transplant is needed. Donor-specific anti-HLA antibodies (DSA) have been recently recognized as an important barrier against successful engraftment of donor cells, which can affect transplant survival. DSA appear more prevalent in this type of transplant due to higher likelihood of alloimmunization of multiparous females against offspring's HLA antigens, and the degree of mismatch. Here we summarize the evidence for the role of DSA in the development of primary graft failure in haploidentical transplantation and provide consensus recommendations from the European Society for Blood and Marrow Transplant Group on testing, monitoring, and treatment of patients with DSA receiving haploidentical hematopoietic progenitor cell transplantation.

  1. Exacerbation of spontaneous autoimmune nephritis following regulatory T cell depletion in B cell lymphoma 2‐interacting mediator knock‐out mice

    PubMed Central

    Wang, Y. M.; Zhang, G. Y.; Wang, Y.; Hu, M.; Zhou, J. J.; Sawyer, A.; Cao, Q.; Wang, Y.; Zheng, G.; Lee, V. W. S.; Harris, D. C. H.

    2017-01-01

    Summary Regulatory T cells (Tregs) have been recognized as central mediators for maintaining peripheral tolerance and limiting autoimmune diseases. The loss of Tregs or their function has been associated with exacerbation of autoimmune disease. However, the temporary loss of Tregs in the chronic spontaneous disease model has not been investigated. In this study, we evaluated the role of Tregs in a novel chronic spontaneous glomerulonephritis model of B cell lymphoma 2‐interacting mediator (Bim) knock‐out mice by transient depleting Tregs. Bim is a pro‐apoptotic member of the B cell lymphoma 2 (Bcl‐2) family. Bim knock‐out (Bim–/–) mice fail to delete autoreactive T cells in thymus, leading to chronic spontaneous autoimmune kidney disease. We found that Treg depletion in Bim–/– mice exacerbated the kidney injury with increased proteinuria, impaired kidney function, weight loss and greater histological injury compared with wild‐type mice. There was a significant increase in interstitial infiltrate of inflammatory cells, antibody deposition and tubular damage. Furthermore, the serum levels of cytokines interleukin (IL)−2, IL‐4, IL‐6, IL‐10, IL‐17α, interferon (IFN)‐γ and tumour necrosis factor (TNF)‐α were increased significantly after Treg depletion in Bim–/– mice. This study demonstrates that transient depletion of Tregs leads to enhanced self‐reactive T effector cell function followed by exacerbation of kidney disease in the chronic spontaneous kidney disease model of Bim‐deficient mice. PMID:28152566

  2. Combination of a Haploidentical Stem Cell Transplant With Umbilical Cord Blood for Cerebral X-Linked Adrenoleukodystrophy.

    PubMed

    Jiang, Hua; Jiang, Min-Yan; Liu, Sha; Cai, Yan-Na; Liang, Cui-Li; Liu, Li

    2015-08-01

    Childhood cerebral X-linked adrenoleukodystrophy is a rapidly progressive neurodegenerative disorder that affects central nervous system myelin and the adrenal cortex. Hematopoietic stem cell transplantation is the best available curative therapy if performed during the early stages of disease. Only 30% of patients who might benefit from a hematopoietic stem cell transplant will have a full human leukocyte antigen-matched donor, which is considered to be the best choice. We present a 5-year-old boy with cerebral X-linked adrenoleukodystrophy whose brain magnetic resonance imaging severity score was 7 and who needed an immediate transplantation without an available full human leukocyte antigen-matched donor. We combined haploidentical and umbilical cord blood sources for transplantation and saw encouraging results. After transplantation, the patient showed neurological stability for 6 months and the level of very long chain fatty acids had decreased. By 1 year, the patient appeared to gradually develop cognition, motor, and visual disturbances resulting from possible mix chimerism. Transplantation of haploidentical stem cells combined with the infusion of umbilical cord blood is a novel approach for treating cerebral X-linked adrenoleukodystrophy. It is critical to monitor posttransplant chimerism and carry out antirejection therapy timely for a beneficial clinical outcome. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Cytomegalovirus reactivation is associated with a lower rate of early relapse in myeloid malignancies independent of in-vivo T cell depletion strategy.

    PubMed

    Hilal, Talal; Slone, Stacey; Peterson, Shawn; Bodine, Charles; Gul, Zartash

    2017-06-01

    The association between cytomegalovirus (CMV) reactivation and relapse risk has not been evaluated in relation to T cell depletion strategies. We evaluated 93 patients who underwent allogeneic hematopoietic stem cell transplantation (HSCT) and analyzed the association between T cell depletion strategies with the cumulative incidence of relapse and CMV reactivation. A total of 33% of patients who received ATG vs. 34% who received alemtuzumab developed CMV reactivation. The cumulative incidence of relapse was 3% at 1year and 20% at 3 years in patients with CMV reactivation vs. 30% at 1year and 38% at 3 years in patients without CMV reactivation (p=0.02). When analyzed separately, this effect persisted in the myeloid, but not the lymphoid group. There was a numerical trend towards increased non-relapse mortality (NRM) in patients with CMV reactivation, especially in the myeloid group. The choice of T cell depleting agent and the rate of CMV reactivation were not associated with different overall survival (OS) rates. These results suggest that the choice of T cell depletion strategy may have similar effects on rates of CMV reactivation, disease relapse, and survival. Further studies examining these variables in patients not exposed to in-vivo T cell depleting agents may be of interest. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Sequential Dysfunction and Progressive Depletion of Candida albicans-Specific CD4 T Cell Response in HIV-1 Infection

    PubMed Central

    Liu, Fengliang; Fan, Xiuzhen; Auclair, Sarah; Ferguson, Monique; Sun, Jiaren; Soong, Lynn; Hou, Wei; Redfield, Robert R.; Birx, Deborah L.; Ratto-Kim, Silvia; Robb, Merlin L.; Kim, Jerome H.; Michael, Nelson L.; Hu, Haitao

    2016-01-01

    Loss of immune control over opportunistic infections can occur at different stages of HIV-1 (HIV) disease, among which mucosal candidiasis caused by the fungal pathogen Candida albicans (C. albicans) is one of the early and common manifestations in HIV-infected human subjects. The underlying immunological basis is not well defined. We have previously shown that compared to cytomegalovirus (CMV)-specific CD4 cells, C. albicans-specific CD4 T cells are highly permissive to HIV in vitro. Here, based on an antiretroviral treatment (ART) naïve HIV infection cohort (RV21), we investigated longitudinally the impact of HIV on C. albicans- and CMV-specific CD4 T-cell immunity in vivo. We found a sequential dysfunction and preferential depletion for C. albicans-specific CD4 T cell response during progressive HIV infection. Compared to Th1 (IFN-γ, MIP-1β) functional subsets, the Th17 functional subsets (IL-17, IL-22) of C. albicans-specific CD4 T cells were more permissive to HIV in vitro and impaired earlier in HIV-infected subjects. Infection history analysis showed that C. albicans-specific CD4 T cells were more susceptible to HIV in vivo, harboring modestly but significantly higher levels of HIV DNA, than CMV-specific CD4 T cells. Longitudinal analysis of HIV-infected individuals with ongoing CD4 depletion demonstrated that C. albicans-specific CD4 T-cell response was preferentially and progressively depleted. Taken together, these data suggest a potential mechanism for earlier loss of immune control over mucosal candidiasis in HIV-infected patients and provide new insights into pathogen-specific immune failure in AIDS pathogenesis. PMID:27280548

  5. Profound CD4+/CCR5+ T cell expansion is induced by CD8+ lymphocyte depletion but does not account for accelerated SIV pathogenesis.

    PubMed

    Okoye, Afam; Park, Haesun; Rohankhedkar, Mukta; Coyne-Johnson, Lia; Lum, Richard; Walker, Joshua M; Planer, Shannon L; Legasse, Alfred W; Sylwester, Andrew W; Piatak, Michael; Lifson, Jeffrey D; Sodora, Donald L; Villinger, Francois; Axthelm, Michael K; Schmitz, Joern E; Picker, Louis J

    2009-07-06

    Depletion of CD8(+) lymphocytes during acute simian immunodeficiency virus (SIV) infection of rhesus macaques (RMs) results in irreversible prolongation of peak-level viral replication and rapid disease progression, consistent with a major role for CD8(+) lymphocytes in determining postacute-phase viral replication set points. However, we report that CD8(+) lymphocyte depletion is also associated with a dramatic induction of proliferation among CD4(+) effector memory T (T(EM)) cells and, to a lesser extent, transitional memory T (T(TrM)) cells, raising the question of whether an increased availability of optimal (activated/proliferating), CD4(+)/CCR5(+) SIV "target" cells contributes to this accelerated pathogenesis. In keeping with this, depletion of CD8(+) lymphocytes in SIV(-) RMs led to a sustained increase in the number of potential CD4(+) SIV targets, whereas such depletion in acute SIV infection led to increased target cell consumption. However, we found that the excess CD4(+) T(EM) cell proliferation of CD8(+) lymphocyte-depleted, acutely SIV-infected RMs was completely inhibited by interleukin (IL)-15 neutralization, and that this inhibition did not abrogate the rapidly progressive infection in these RMs. Moreover, although administration of IL-15 during acute infection induced robust CD4(+) T(EM) and T(TrM) cell proliferation, it did not recapitulate the viral dynamics of CD8(+) lymphocyte depletion. These data suggest that CD8(+) lymphocyte function has a larger impact on the outcome of acute SIV infection than the number and/or activation status of target cells available for infection and viral production.

  6. Distinct Biomarker Profiles in Ex Vivo T Cell Depletion Graft Manipulation Strategies: CD34+ Selection versus CD3+/19+ Depletion in Matched Sibling Allogeneic Peripheral Blood Stem Cell Transplantation.

    PubMed

    Cantilena, Caroline R; Ito, Sawa; Tian, Xin; Jain, Prachi; Chinian, Fariba; Anandi, Prathima; Keyvanfar, Keyvan; Draper, Debbie; Koklanaris, Eleftheria; Hauffe, Sara; Superata, Jeanine; Stroncek, David; Muranski, Pawel; Barrett, A John; Battiwalla, Minoo

    2018-03-01

    Various approaches have been developed for ex vivo T cell depletion in allogeneic stem cell transplantation to prevent graft-versus-host disease (GVHD). Direct comparisons of T cell depletion strategies have not been well studied, however. We evaluated cellular and plasma biomarkers in 2 different graft manipulation strategies, CD3 + CD19 + cell depletion (CD3/19D) versus CD34 + selection (CD34S), and their associations with clinical outcomes. Identical conditions, including the myeloablative preparative regimen, HLA-identical sibling donor, GVHD prophylaxis, and graft source, were used in the 2 cohorts. Major clinical outcomes were similar in the 2 groups in terms of overall survival, nonrelapse mortality, and cumulative incidence of relapse; however, the cumulative incidence of acute GVHD trended to be higher in the CD3/19D cohort compared with the CD34S cohort. A distinct biomarker profile was noted in the CD3/19D cohort: higher levels of ST2, impaired Helios - FoxP3 + Treg reconstitution, and rapid reconstitution of naïve, Th2, and Th17 CD4 cells in the early post-transplantation period. In vitro graft replication studies confirmed that CD3/19D disproportionately depleted Tregs and other CD4 subset repertoires in the graft. This study confirms the utility of biomarker monitoring, which can be directly correlated with biological consequences and possible future therapeutic indications. Published by Elsevier Inc.

  7. Depletion of host CCR7(+) dendritic cells prevented donor T cell tissue tropism in anti-CD3-conditioned recipients.

    PubMed

    He, Wei; Racine, Jeremy J; Johnston, Heather F; Li, Xiaofan; Li, Nainong; Cassady, Kaniel; Liu, Can; Deng, Ruishu; Martin, Paul; Forman, Stephen; Zeng, Defu

    2014-07-01

    We reported previously that anti-CD3 mAb treatment before hematopoietic cell transplantation (HCT) prevented graft-versus-host disease (GVHD) and preserved graft-versus-leukemia (GVL) effects in mice. These effects were associated with downregulated donor T cell expression of tissue-specific homing and chemokine receptors, marked reduction of donor T cell migration into GVHD target tissues, and deletion of CD103(+) dendritic cells (DCs) in mesenteric lymph nodes (MLN). MLN CD103(+) DCs and peripheral lymph node (PLN) DCs include CCR7(+) and CCR7(-) subsets, but the role of these DC subsets in regulating donor T cell expression of homing and chemokine receptors remain unclear. Here, we show that recipient CCR7(+), but not CCR7(-), DCs in MLN induced donor T cell expression of gut-specific homing and chemokine receptors in a retinoid acid-dependent manner. CCR7 regulated activated DC migration from tissue to draining lymph node, but it was not required for the ability of DCs to induce donor T cell expression of tissue-specific homing and chemokine receptors. Finally, anti-CD3 treatment depleted CCR7(+) but not CCR7(-) DCs by inducing sequential expansion and apoptosis of CCR7(+) DCs in MLN and PLN. Apoptosis of CCR7(+) DCs was associated with DC upregulation of Fas expression and natural killer cell but not T, B, or dendritic cell upregulation of FasL expression in the lymph nodes. These results suggest that depletion of CCR7(+) host-type DCs, with subsequent inhibition of donor T cell migration into GVHD target tissues, can be an effective approach in prevention of acute GVHD and preservation of GVL effects. Copyright © 2014 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  8. 6-Thioguanine-loaded polymeric micelles deplete myeloid-derived suppressor cells and enhance the efficacy of T cell immunotherapy in tumor-bearing mice

    DOE PAGES

    Jeanbart, Laura; Kourtis, Iraklis C.; van der Vlies, André J.; ...

    2015-05-16

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells that suppress effector T cell responses and can reduce the efficacy of cancer immunotherapies. We previously showed that ultra-small polymer nanoparticles efficiently drain to the lymphatics after intradermal injection and target antigen-presenting cells, including Ly6c hi Ly6g ₋monocytic MDSCs (Mo-MDSCs), in skin-draining lymph nodes (LNs) and spleen. Here, we developed ultra-small polymer micelles loaded with 6-thioguanine (MC-TG), a cytotoxic drug used in the treatment of myelogenous leukemia, with the aim of killing Mo-MDSCs in tumor-bearing mice and thus enhancing T cell-mediated anti-tumor responses. We found that 2 daysmore » post-injection in tumor-bearing mice (B16-F10 melanoma or E.G7-OVA thymoma), MC-TG depleted Mo-MDSCs in the spleen, Ly6c lo Ly6g + granulocytic MDSCs (G-MDSCs) in the draining LNs, and Gr1 int Mo-MDSCs in the tumor. In both tumor models, MC-TG decreased the numbers of circulating Mo- and G-MDSCs, as well as of Ly6c hi macrophages, for up to 7 days following a single administration. MDSC depletion was dose dependent and more effective with MC-TG than with equal doses of free TG. Finally, we tested whether this MDSC-depleting strategy might enhance cancer immunotherapies in the B16-F10 melanoma model. We found that MC-TG significantly improved the efficacy of adoptively transferred, OVA-specific CD8 + T cells in melanoma cells expressing OVA. Ultimately, these findings highlight the capacity of MC-TG in depleting MDSCs in the tumor microenvironment and show promise in promoting anti-tumor immunity when used in combination with T cell immunotherapies.« less

  9. 6-Thioguanine-loaded polymeric micelles deplete myeloid-derived suppressor cells and enhance the efficacy of T cell immunotherapy in tumor-bearing mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jeanbart, Laura; Kourtis, Iraklis C.; van der Vlies, André J.

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells that suppress effector T cell responses and can reduce the efficacy of cancer immunotherapies. We previously showed that ultra-small polymer nanoparticles efficiently drain to the lymphatics after intradermal injection and target antigen-presenting cells, including Ly6c hi Ly6g ₋monocytic MDSCs (Mo-MDSCs), in skin-draining lymph nodes (LNs) and spleen. Here, we developed ultra-small polymer micelles loaded with 6-thioguanine (MC-TG), a cytotoxic drug used in the treatment of myelogenous leukemia, with the aim of killing Mo-MDSCs in tumor-bearing mice and thus enhancing T cell-mediated anti-tumor responses. We found that 2 daysmore » post-injection in tumor-bearing mice (B16-F10 melanoma or E.G7-OVA thymoma), MC-TG depleted Mo-MDSCs in the spleen, Ly6c lo Ly6g + granulocytic MDSCs (G-MDSCs) in the draining LNs, and Gr1 int Mo-MDSCs in the tumor. In both tumor models, MC-TG decreased the numbers of circulating Mo- and G-MDSCs, as well as of Ly6c hi macrophages, for up to 7 days following a single administration. MDSC depletion was dose dependent and more effective with MC-TG than with equal doses of free TG. Finally, we tested whether this MDSC-depleting strategy might enhance cancer immunotherapies in the B16-F10 melanoma model. We found that MC-TG significantly improved the efficacy of adoptively transferred, OVA-specific CD8 + T cells in melanoma cells expressing OVA. Ultimately, these findings highlight the capacity of MC-TG in depleting MDSCs in the tumor microenvironment and show promise in promoting anti-tumor immunity when used in combination with T cell immunotherapies.« less

  10. Alpha/Beta T-Cell Depleted Grafts as an Immunological Booster to Treat Graft Failure after Hematopoietic Stem Cell Transplantation with HLA-Matched Related and Unrelated Donors

    PubMed Central

    Rådestad, E.; Wikell, H.; Engström, M.; Watz, E.; Sundberg, B.; Thunberg, S.; Uzunel, M.; Mattsson, J.; Uhlin, M.

    2014-01-01

    Allogeneic hematopoietic stem cell transplantation is associated with several complications and risk factors, for example, graft versus host disease (GVHD), viral infections, relapse, and graft rejection. While high levels of CD3+ cells in grafts can contribute to GVHD, they also promote the graft versus leukemia (GVL) effect. Infusions of extra lymphocytes from the original stem cell donor can be used as a treatment after transplantation for relapse or poor immune reconstitution but also they increase the risk for GVHD. In peripheral blood, 95% of T-cells express the αβ T-cell receptor and the remaining T-cells express the γδ T-cell receptor. As αβ T-cells are the primary mediators of GVHD, depleting them from the graft should reduce this risk. In this pilot study, five patients transplanted with HLA-matched related and unrelated donors were treated with αβ T-cell depleted stem cell boosts. The majority of γδ T-cells in the grafts expressed Vδ2 and/or Vγ9. Most patients receiving αβ-depleted stem cell boosts increased their levels of white blood cells, platelets, and/or granulocytes 30 days after infusion. No signs of GVHD or other side effects were detected. A larger pool of patients with longer follow-up time is needed to confirm the data in this study. PMID:25371909

  11. Late-onset Epstein-Barr virus-related disease in acute leukemia patients after haploidentical hematopoietic stem cell transplantation is associated with impaired early recovery of T and B lymphocytes.

    PubMed

    Liu, Jiangying; Yan, Chenhua; Zhang, Chunli; Xu, Lanping; Liu, Yanrong; Huang, Xiaojun

    2015-10-01

    Epstein-Barr virus-related disease (EBVD) is a serious clinical complication in patients who have undergone haploidentical hematopoietic stem cell transplantation (haploHSCT). Some recipients develop EBVD relatively late after haploHSCT, and most of these patients suffer a poor outcome. This retrospective cohort study characterized the early adaptive immune recovery of patients with acute leukemia presenting with EBVD more than 100 d after haploHSCT. Patients with acute leukemia who received haploHSCT and developed EBVD 100 d later (n = 8) were compared with a matched control group without EBVD (n = 24) with regard to peripheral WBC, lymphocytes, and neutrophils (at 30, 60, and 90 d) and recoveries of B and T lymphocytes (at 30 and 90 d, via immunophenotyping/flow cytometry). Ninety days after haploHSCT, the median values of WBCs and lymphocytes, and the recoveries of CD19(+) B cells and CD4(+) , CD8(+) , and CD4(+) CD45RO(+) T cells, were significantly lower in patients who developed EBVD, relative to the control group. These results suggest a significant association between deficient early recovery of B and T lymphocytes and the development of late-onset EBVD after haploHSCT. Our observation could facilitate clinical intervention and the improvement of overall survival of patients undergoing haploHSCT. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. CD56-enriched donor cell infusion after post-transplantation cyclophosphamide for haploidentical transplantation of advanced myeloid malignancies is associated with prompt reconstitution of mature natural killer cells and regulatory T cells with reduced incidence of acute graft versus host disease: A pilot study.

    PubMed

    Jaiswal, Sarita Rani; Zaman, Shamsur; Nedunchezhian, Murugaiyan; Chakrabarti, Aditi; Bhakuni, Prakash; Ahmed, Margoob; Sharma, Kanika; Rawat, Sheh; O'donnell, Paul; Chakrabarti, Suparno

    2017-04-01

    We conducted a pilot study on the feasibility of CD56-enriched donor cell infusion after post-transplantation cyclophosphamide (PTCy) for 10 patients with advanced myeloid malignancies undergoing haploidentical peripheral blood stem cell transplantation with cyclosporine alone as graft-versus-host disease (GVHD) prophylaxis and compared the outcome and immune reconstitution with a control group of 20 patients undergoing the same without CD56-enriched donor cell infusion. An early and rapid surge of mature NK cells as well as CD4 + T cells and regulatory T cells (Tregs) was noted compared with the control group. KIR of donor phenotype reconstituted as early as day 30 with expression of CD56 dim CD16 + NKG2A - KIR + phenotype. None experienced viral or fungal infections, and non-relapse mortality was 10% only. The incidence of grade 2-4 acute GVHD was 50% in the control group with none in the CD56 group (P = 0.01). Only two had de novo chronic GVHD in each group. Relapse occurred in five patients in CD56 group with a median follow-up of 12 months, similar to the control group. Our preliminary data show that CD56 + donor cell infusion after PTCy and short-course cyclosporine is feasible with prompt engraftment, rapid reconstitution of CD4 + T cells, Tregs and NK cells and reduced incidence of acute GVHD. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  13. Novel method for in vitro depletion of T cells by monoclonal antibody-targeted photosensitization.

    PubMed

    Berki, T; Németh, P

    1998-02-01

    An immunotargeting method (called photo-immunotargeting) has been developed for selective in vitro cell destruction. The procedure combines the photosensitizing (toxic) effect of light-induced dye-molecules, e.g., hematoporphyrin (HP) and the selective binding ability of monoclonal antibodies (mAb) to cell surface molecules. The photosensitizer HP molecules were covalently attached to monoclonal antibodies (a-Thy-1) recognizing an antigen on the surface of T lymphocytes, and used for T cell destruction. To increase the selectivity of the conventional targeting methods, a physical activation step (local light irradiation) as a second degree of specificity was employed. The HP in conjugated form was sufficient to induce T cell (thymocytes, EL-4 cell line) death after irradiation at 400 nm, at tenfold lower concentration compared to the photosensitizing effect of unbound HP. The selective killing of T lymphocytes (bearing the Thy-1 antigen) in a mixed cell population was demonstrated after a treatment with the phototoxic conjugate and light irradiation. This method can be useful for selective destruction of one population (target cell) in an in vitro heterogeneous cell mixture, e.g., in bone marrow transplants for T cell depletion to avoid graft vs. host reaction.

  14. Effects of in vivo injection of anti-chicken CD25 monoclonal antibody on regulatory T cell depletion and CD4+CD25- T cell properties in chickens.

    PubMed

    Shanmugasundaram, Revathi; Selvaraj, Ramesh K

    2012-03-01

    Regulatory T cells (Tregs) are defined as CD4(+)CD25(+) cells in chickens. This study examined the effects of an anti-chicken CD25 monoclonal antibody injection (0.5 mg/bird) on in vivo depletion of Tregs and the properties of CD4(+)CD25(-) cells in Treg-depleted birds. The CD4(+)CD25(+) cell percentage in the blood was lower at 8 d post injection than at 0 d. Anti-CD25-mediated CD4(+)CD25(+) cell depletion in blood was maximum at 12 d post injection. The anti-CD25 antibody injection depleted CD4(+)CD25(+) cells in the spleen and cecal tonsils, but not in the thymus, at 12 d post antibody injection. CD4(+)CD25(-) cells from the spleen and cecal tonsils of birds injected with the anti-chicken CD25 antibody had higher proliferation and higher IL-2 and IFNγ mRNA amounts than the controls at 12 d post injection. At 20 d post injection, CD4(+)CD25(+) cell percentages in the blood, spleen and thymus were comparable to that of the 0 d post injection. It could be concluded that anti-chicken CD25 injection temporarily depleted Treg population and increased and IL-2 and IFNγ mRNA amounts in CD4(+)CD25(-) cells at 12d post injection. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Outcomes of haploidentical stem cell transplantation for chronic lymphocytic leukemia: a retrospective study on behalf of the chronic malignancies working party of the EBMT.

    PubMed

    van Gorkom, Gwendolyn; van Gelder, Michel; Eikema, Dirk-Jan; Blok, Henric-Jan; van Lint, M T; Koc, Yener; Ciceri, Fabio; Beelen, Dietrich; Chevallier, Patrice; Selleslag, Dominik; Blaise, Didier; Foá, Roberto; Corradini, Paolo; Castagna, Luca; Moreno, Carol; Solano, Carlos; Müller, Lutz Peter; Tischer, Johanna; Hilgendorf, Inken; Hallek, Michael; Bittenbring, Jörg; Theobald, Matthias; Schetelig, Johannes; Kröger, Nicolaus

    2018-03-01

    Allogeneic hematopoietic stem cell transplantation (HCT) may result in long-term disease control in high-risk chronic lymphocytic leukemia (CLL). Recently, haploidentical HCT is gaining interest because of better outcomes with post-transplantation cyclophosphamide (PTCY). We analyzed patients with CLL who received an allogeneic HCT with a haploidentical donor and whose data were available in the EBMT registry. In total 117 patients (74% males) were included; 38% received PTCY as GVHD prophylaxis. For the whole study cohort OS at 2 and 5 yrs was 48 and 38%, respectively. PFS at 2 and 5 yrs was 38 and 31%, respectively. Cumulative incidence (CI) of NRM in the whole group at 2 and 5 years were 40 and 44%, respectively. CI of relapse at 2 and 5 yrs were 22 and 26%, respectively. All outcomes were not statistically different in patients who received PTCY compared to other types of GVHD prophylaxis. In conclusion, results of haploidentical HCT in CLL seem almost identical to those with HLA-matched donors. Thereby, haploidentical HCT is an appropriate alternative in high risk CLL patients with a transplant indication but no available HLA-matched donor. Despite the use of PTCY, the CI of relapse seems not higher than observed after HLA-matched HCT.

  16. Depletion of CD8 Memory T Cells for Induction of Tolerance of a Previously Transplanted Kidney Allograft

    PubMed Central

    Koyama, I.; Nadazdin, O.; Boskovic, S.; Ochiai, T.; Smith, R. N.; Sykes, M.; Sogawa, H.; Murakami, T.; Strom, T. B.; Colvin, R. B.; Sachs, D. H.; Benichou, G.; Cosimi, A. B.; Kawai, T.

    2013-01-01

    Heterologous immunologic memory has been considered a potent barrier to tolerance induction in primates. Induction of such tolerance for a previously transplanted organ may be more difficult, because specific memory cells can be induced and activated by a transplanted organ. In the current study, we attempted to induce tolerance to a previously transplanted kidney allograft in nonhuman primates. The conditioning regimen consisted of low dose total body irradiation, thymic irradiation, antithymocyte globulin, and anti- CD154 antibody followed by a brief course of a calcineurin inhibitor. This regimen had been shown to induce mixed chimerism and allograft tolerance when kidney transplantation (KTx) and donor bone marrow transplantation (DBMT) were simultaneously performed. However, the same regimen failed to induce mixed chimerism when delayed DBMT was performed after KTx. We found that significant levels of memory T cells remained after conditioning, despite effective depletion of naïve T cells. By adding humanized anti-CD8 monoclonal antibody (cM-T807), CD8 memory T cells were effectively depleted and these recipients successfully achieved mixed chimerism and tolerance. The current studies provide ‘proof of principle’ that the mixed chimerism approach can induce renal allograft tolerance, even late after organ transplantation if memory T-cell function is adequately controlled. PMID:17286617

  17. Comparable post-relapse outcomes between haploidentical and matched related donor allogeneic stem cell transplantation.

    PubMed

    Ma, Y-R; Xu, L-P; Zhang, X-H; Yan, C-H; Wang, Y; Wang, F-R; Wang, J-Z; Chen, Y; Han, W; Chen, Y-H; Chen, H; Liu, K-Y; Huang, X-J

    2017-03-01

    We investigated the impact of donor type on post-relapse survival (PRS) in 85 patients with hematological relapse after their first allogeneic hematological stem cell transplantation (allo-HSCT) for hematological malignancy. The median follow-up was 64 months among survivors. Both 3-year overall survival and 3-year PRS were similar in haploidentical donor (HID) and matched sibling donor (MRD) transplantation (13.0%±4.7% vs 19.4%±7.1%, P=0.913 and 7.7±3.9% vs 9.7±5.3%, P= 0.667). Higher rates of post-relapse grade II-IV and III-IV acute GvHD (aGvHD) were observed in HID transplantation patients. A higher cumulative incidence of post-relapse extensive chronic GvHD was also observed for HID transplantation patients. Multivariate analyses confirmed that treatment including donor lymphocyte infusion (DLI), late relapse >1 year, and in first CR at transplantation were associated with superior PRS (P=0.012, hazard ratio (HR)=0.527 (0.320-0.866)); P=0.033, HR=0.534 (0.300-0.952) and P=0.046, HR=0.630 (0.400-0.992). The data suggest that post-relapse outcomes are comparable in HID and MRD transplantation, and that DLI is safe for relapsed patients after haploidentical transplantation.

  18. B cell helper factors. II. Synergy among three helper factors in the response of T cell- and macrophage-depleted B cells.

    PubMed

    Liebson, H J; Marrack, P; Kappler, J

    1982-10-01

    The concanavalin A- (Con A) stimulated supernatant of normal spleen cells (normal Con A SN) was shown to contain a set of helper factors sufficient to allow T cell- and macrophage- (M phi) depleted murine splenic B cells to produce a plaque-forming cell response to the antigen sheep red blood cells (SRBC). The activity of normal Con A SN could be reconstituted by a mixture of three helper factor preparations. The first was the interleukin 2- (IL 2) containing Con A SN of the T cell hybridoma, FS6-14.13. The second was a normal Con A SN depleted of IL 2 by extended culture with T cell blasts from which the 30,000 to 50,000 m.w. factors were isolated (interleukin X, IL X). The third was a SN either from the M phi tumor cell line P388D1 or from normal M phi taken from Corynebacterium parvum-immune mice. The combination of all three helper factor preparations was required to equal the activity of normal Con A SN; however, the M phi SN had the least overall effect. The M phi SN and IL 2 had to be added at the initiation of the culture period for a maximal effect, but the IL X preparation was most effective when added 24 hr after the initiation of culture. These results indicate that at least three nonspecific helper factors contribute to the helper activity in normal Con A SN.

  19. Stability of Chimerism in Non-Obese Diabetic Mice Achieved By Rapid T Cell Depletion Is Associated With High Levels of Donor Cells Very Early After Transplant.

    PubMed

    Lin, Jiaxin; Chan, William F N; Boon, Louis; Anderson, Colin C

    2018-01-01

    Stable mixed hematopoietic chimerism is a robust method for inducing donor-specific tolerance with the potential to prevent rejection of donor islets in recipients with autoimmune type-1 diabetes. However, with reduced intensity conditioning, fully allogeneic chimerism in a tolerance resistant autoimmune-prone non-obese diabetic (NOD) recipient has rarely been successful. In this setting, successful multilineage chimerism has required either partial major histocompatability complex matching, mega doses of bone marrow, or conditioning approaches that are not currently clinically feasible. Irradiation free protocols with moderate bone marrow doses have not generated full tolerance; donor skin grafts were rejected. We tested whether more efficient recipient T cell depletion would generate a more robust tolerance. We show that a combination of donor-specific transfusion-cyclophosphamide and multiple T cell depleting antibodies could induce stable high levels of fully allogeneic chimerism in NOD recipients. Less effective T cell depletion was associated with instability of chimerism. Stable chimeras appeared fully donor-specific tolerant, with clonal deletion of allospecific T cells and acceptance of donor skin grafts, while recovering substantial immunocompetence. The loss of chimerism months after transplant was significantly associated with a lower level of chimerism and donor T cells within the first 2 weeks after transplant. Thus, rapid and robust recipient T cell depletion allows for stable high levels of fully allogeneic chimerism and robust donor-specific tolerance in the stringent NOD model while using a clinically feasible protocol. In addition, these findings open the possibility of identifying recipients whose chimerism will later fail, stratifying patients for early intervention.

  20. Abrogation of graft-vs.-leukemia activity after depletion of CD3+ T cells in a murine model of MHC-matched peripheral blood progenitor cell transplantation (PBPCT).

    PubMed

    Uharek, L; Glass, B; Zeis, M; Dreger, P; Steinmann, J; Löffler, H; Schmitz, N

    1998-02-01

    Using a murine transplantation model, we simulated a clinical situation in which major histocompatibility complex (MHC)-identical allogeneic peripheral blood progenitor cells (PBPCs) are transplanted for the treatment of a malignant disease that is resistant to resting natural killer (NK) cells but sensitive to cytokine-activated NK cells and T cell-mediated antitumor activity. We determined the influence of selective T cell depletion of allogeneic PBPC grafts on graft-vs.-leukemia (GVL) activity and investigated the effectiveness of ex vivo treatment with NK cell-activating cytokines to compensate for the putative loss of T cell-derived factors stimulating natural cytotoxicity. After pretreatment of Balb/c (H-2d) recipients with 7.5 Gy of total body irradiation, 2x10(7) rhG-CSF-mobilized PBPCs of splenectomized syngeneic or MHC-identical DBA (H-2d) mice were transferred. Selective T cell depletion (TCD) was performed by immunomagnetic purging with a mononoclonal antibody directed against CD3. In some experimental groups, T cell-depleted PBPCs were incubated with 200 U/mL interleukin (IL)-2 and 100 U/mL IL-12 for 24 hours. To investigate antileukemic activity in vivo, recipient mice were inoculated with 1x10(5) A20 cells (a B-lymphoblastic leukemia of Balb/c origin) 2 days before PBPC transplantation (PBPCT). After transplantation of unmanipulated allogeneic cells, 25% of the animals died with signs of graft-vs.-host disease (GVHD) but 71% were free from relapse 100 days after PBPCT. After TCD of allogeneic grafts with anti-CD3, the incidence of GVH-related mortality was below 5% but the leukemia-free survival rate was significantly (p < 0.05) decreased to 25% and thus was similar to that observed after syngeneic PBPCT (17%). When CD3-depleted grafts were incubated with IL-2 and IL-12, 45% of the animals remained free from leukemia; however, the difference was not statistically significant. Our results suggest that ex vivo activation of residual NK cells with IL-2

  1. Depletion of regulatory T cells by anti-ICOS antibody enhances anti-tumor immunity of tumor cell vaccine in prostate cancer.

    PubMed

    Mo, Lijun; Chen, Qianmei; Zhang, Xinji; Shi, Xiaojun; Wei, Lili; Zheng, Dianpeng; Li, Hongwei; Gao, Jimin; Li, Jinlong; Hu, Zhiming

    2017-10-13

    ICOS + Treg cells exert important immunosuppressive effects in tumor immunity. We adopt a combination approach of ICOS + Treg cells depletion with tumor cell vaccine to evaluate anti-tumor immunity in mouse prostate cancer model. Streptavidin (SA)-mGM-CSF surface-modified RM-1 cells were prepared as the vaccine and the mouse subcutaneous prostate tumor model was used to evaluate the immunity. Tumor growth, flow cytometry, immunohistochemistry, immunofluorescence and enzyme linked immunosorbent assay (ELISA) were performed to evaluate the therapeutic effects. Our results demonstrated that SA-mGM-CSF vaccine was prepared successfully and tumor growth was inhibited. The tumor size in the combination group was much smaller than that in the vaccine with IgG mAb group. The portions of dendritic cells, CD8 + and CD4 + T cells in the mice blood and tumor tissues were increased after treatment with vaccine. There were more immune-suppressing Tregs infiltrated into tumor after treatment with tumor cell vaccine, and ICOS blocking could deplete the infiltrated Tregs, and T lymphocytes increased more dramatically in the combination therapy group. The concentrations of interferon-γ were increased in all vaccine group, the concentrations of Interleukin-10 and Interleukin-4 were much lower in the combination group. Our study demonstrated that ICOS blocking could deplete the tumor-infiltrated ICOS + Treg cells. Combining GM-CSF surface-modified RM-1 cell vaccine with Anti-ICOS antibody could induce better antitumor immunity than a vaccine alone. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Clinical grade isolation of regulatory T cells from G-CSF mobilized peripheral blood improves with initial depletion of monocytes

    PubMed Central

    Patel, Pritesh; Mahmud, Dolores; Park, Youngmin; Yoshinaga, Kazumi; Mahmud, Nadim; Rondelli, Damiano

    2015-01-01

    Clinical isolation of circulating CD4+CD25+ regulatory T cells (Tregs) from peripheral blood mononuclear cells is usually performed by CD4+ cell negative selection followed by CD25+ cell positive selection. Although G-CSF mobilized peripheral blood (G-PBSC) contains a high number of Tregs, a high number of monocytes in G-PBSC limits Treg isolation. Using a small scale device (MidiMACS, Miltenyi) we initially demonstrated that an initial depletion of monocytes would be necessary to obtaina separation of CD4+CD25+FoxP3+CD127- cells from G-PBSC (G-Tregs) with a consistent purity >70% and inhibitory activity of T cell alloreactivity in-vitro. We then validated the same approach in a clinical scale setting by separating G-Tregs with clinically available antibodies to perform a CD8+CD19+CD14+ cell depletion followed by CD25+ cell selection (2-step process) or by adding an initial CD14+ cell depletion (3-step process) using a CliniMACS column. The 3-step approach resulted in a better purity (81±12% vs. 35±33%) and yield (66% vs. 39%). Clinically isolated G-Tregs were also FoxP3+CD127dim and functionally suppressive in-vitro. Our findings suggest that a better and more consistent purity of Tregs can be achieved from G-PBSC by an initial single depletion of monocytes prior to selection of CD4+CD25+ cells. PMID:27069755

  3. Transient hemolysis due to anti-D and anti-A1 produced by engrafted donor's lymphocytes after allogeneic unmanipulated haploidentical hematopoietic stem cell transplantation.

    PubMed

    Bailén, Rebeca; Kwon, Mi; Pérez-Corral, Ana María; Pascual, Cristina; Buño, Ismael; Balsalobre, Pascual; Serrano, David; Gayoso, Jorge; Díez-Martín, José Luis; Anguita, Javier

    2017-10-01

    Development of de novo alloantibodies against recipient's red blood cell (RBC) antigens by engrafted donor's lymphocytes is a known phenomenon in the setting of allogeneic hematopoietic stem cell transplantation (HSCT). This situation is usually clinically insignificant. We report a case of early clinically relevant hemolytic anemia in a blood group A 1 D+ patient, due to a limited production of anti-D and anti-A 1 produced by nonpreviously sensitized newly engrafted donor's immune system. A 31-year-old Caucasian woman, blood group A 1 , D+, with Hodgkin's lymphoma, received an unmanipulated haploidentical allogeneic peripheral blood HSCT after a nonmyeloablative conditioning regimen. Donor blood group was A 2 B, D-. The patient had an uneventful course until Day +34, when she developed clinically significant hemolytic anemia with a positive direct antiglobulin test. Anti-D and anti-A 1 produced by the donor-engrafted lymphocytes were detected both in serum and in eluate. The hemolysis produced an accelerated group change, turning the patient's ABO group into A 2 B 2 weeks after the detection of the alloantibodies. As the residual patient's RBCs progressively disappeared, anti-D and anti-A 1 production decreased and were not detected in serum by Day +41. This case illustrates that de novo alloantibody production against ABO and D antigens by the newly engrafted donor's lymphocytes can occasionally cause clinically significant anemia. To our knowledge, this is the first case reported of clinically significant hemolytic anemia due to a transient anti-D anti-A 1 alloimmunization after T-cell-repleted haploidentical HSCT. © 2017 AABB.

  4. CD127 and CD25 expression defines CD4+ T cell subsets that are differentially depleted during HIV infection.

    PubMed

    Dunham, Richard M; Cervasi, Barbara; Brenchley, Jason M; Albrecht, Helmut; Weintrob, Amy; Sumpter, Beth; Engram, Jessica; Gordon, Shari; Klatt, Nichole R; Frank, Ian; Sodora, Donald L; Douek, Daniel C; Paiardini, Mirko; Silvestri, Guido

    2008-04-15

    Decreased CD4(+) T cell counts are the best marker of disease progression during HIV infection. However, CD4(+) T cells are heterogeneous in phenotype and function, and it is unknown how preferential depletion of specific CD4(+) T cell subsets influences disease severity. CD4(+) T cells can be classified into three subsets by the expression of receptors for two T cell-tropic cytokines, IL-2 (CD25) and IL-7 (CD127). The CD127(+)CD25(low/-) subset includes IL-2-producing naive and central memory T cells; the CD127(-)CD25(-) subset includes mainly effector T cells expressing perforin and IFN-gamma; and the CD127(low)CD25(high) subset includes FoxP3-expressing regulatory T cells. Herein we investigated how the proportions of these T cell subsets are changed during HIV infection. When compared with healthy controls, HIV-infected patients show a relative increase in CD4(+)CD127(-)CD25(-) T cells that is related to an absolute decline of CD4(+)CD127(+)CD25(low/-) T cells. Interestingly, this expansion of CD4(+)CD127(-) T cells was not observed in naturally SIV-infected sooty mangabeys. The relative expansion of CD4(+)CD127(-)CD25(-) T cells correlated directly with the levels of total CD4(+) T cell depletion and immune activation. CD4(+)CD127(-)CD25(-) T cells were not selectively resistant to HIV infection as levels of cell-associated virus were similar in all non-naive CD4(+) T cell subsets. These data indicate that, during HIV infection, specific changes in the fraction of CD4(+) T cells expressing CD25 and/or CD127 are associated with disease progression. Further studies will determine whether monitoring the three subsets of CD4(+) T cells defined based on the expression of CD25 and CD127 should be used in the clinical management of HIV-infected individuals.

  5. Depletion of CD52-positive cells inhibits the development of central nervous system autoimmune disease, but deletes an immune-tolerance promoting CD8 T-cell population. Implications for secondary autoimmunity of alemtuzumab in multiple sclerosis.

    PubMed

    von Kutzleben, Stephanie; Pryce, Gareth; Giovannoni, Gavin; Baker, David

    2017-04-01

    The objective was to determine whether CD52 lymphocyte depletion can act to promote immunological tolerance induction by way of intravenous antigen administration such that it could be used to either improve efficiency of multiple sclerosis (MS) inhibition or inhibit secondary autoimmunities that may occur following alemtuzumab use in MS. Relapsing experimental autoimmune encephalomyelitis was induced in ABH mice and immune cell depletion was therapeutically applied using mouse CD52 or CD4 (in conjunction with CD8 or CD20) depleting monoclonal antibodies. Immunological unresponsiveness was then subsequently induced using intravenous central nervous system antigens and responses were assessed clinically. A dose-response of CD4 monoclonal antibody depletion indicated that the 60-70% functional CD4 T-cell depletion achieved in perceived failed trials in MS was perhaps too low to even stop disease in animals. However, more marked (~75-90%) physical depletion of CD4 T cells by CD4 and CD52 depleting antibodies inhibited relapsing disease. Surprisingly, in contrast to CD4 depletion, CD52 depletion blocked robust immunological unresponsiveness through a mechanism involving CD8 T cells. Although efficacy was related to the level of CD4 T-cell depletion, the observations that CD52 depletion of CD19 B cells was less marked in lymphoid organs than in the blood provides a rationale for the rapid B-cell hyper-repopulation that occurs following alemtuzumab administration in MS. That B cells repopulate in the relative absence of T-cell regulatory mechanisms that promote immune tolerance may account for the secondary B-cell autoimmunities, which occur following alemtuzumab treatment of MS. © 2016 The Authors. Immunology Published by John Wiley & Sons Ltd.

  6. Depletion of CD20 B cells fails to inhibit relapsing mouse experimental autoimmune encephalomyelitis.

    PubMed

    Sefia, Eseberuo; Pryce, Gareth; Meier, Ute-Christiane; Giovannoni, Gavin; Baker, David

    2017-05-01

    Multiple sclerosis (MS) is often considered to be a CD4, T cell-mediated disease. This is largely based on the capacity of CD4 T cells to induce relapsing experimental autoimmune encephalomyelitis (EAE) in rodents. However, CD4-depletion using a monoclonal antibody was considered unsuccessful and relapsing MS responds well to B cell depletion via CD20 B cell depleting antibodies. The influence of CD20 B cell depletion in relapsing EAE was assessed. Relapsing EAE was induced in Biozzi ABH mice. These were treated with CD20-specific (18B12) antibody and the influence on CD45RA-B220 B cell depletion and clinical course was analysed. Relapsing EAE in Biozzi ABH failed to respond to the marked B cell depletion induced with a CD20-specific antibody. In contrast to CD20 and CD8-specific antibodies, CD4 T cell depletion inhibited EAE. Spinal cord antigen-induced disease in ABH mice is CD4 T cell-dependent. The lack of influence of CD20 B cell depletion in relapsing EAE, coupled with the relatively marginal and inconsistent results obtained in other mouse studies, suggests that rodents may have limited value in understanding the mechanism occurring following CD20 B cell depletion in humans. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. The incidence, risk factors, and outcomes of primary poor graft function after unmanipulated haploidentical stem cell transplantation.

    PubMed

    Sun, Yu-Qian; He, Gan-Lin; Chang, Ying-Jun; Xu, Lan-Ping; Zhang, Xiao-Hui; Han, Wei; Chen, Huan; Chen, Yu-Hong; Wang, Yu; Wang, Feng-Rong; Wang, Jing-Zhi; Liu, Kai-Yan; Huang, Xiao-Jun

    2015-10-01

    Primary poor graft function (PGF) is a severe complication after allogeneic stem cell transplantation (SCT). The incidence, risk factors, and outcomes of PGF have not been well described, especially in the haploidentical SCT setting. We retrospectively reviewed patients who received haploidentical SCT at Peking University Institute of Hematology between January 1, 2011, and December 31, 2012. PGF was defined as persistent neutropenia (≤0.5 × 10(9) L(-1)), thrombocytopenia (platelets ≤20 × 10(9) L(-1)), and/or hemoglobin ≤70 g L(-1) after engraftment with hypocellular bone marrow and full donor chimerism, without concurrent graft-versus-host disease or disease relapse. Incidence was calculated from all patients. Of the 464 total patients, 26 (5.6 %) developed primary PGF. The risk factors were analyzed and compared with control patients with good graft function who were selected using the case-pair method. Finally, 104 patients were selected as a control group according to the matching conditions: (1) the type (acute leukemia, myelodysplastic syndrome (MDS), chronic myelogenous leukemia (CML)) and status (standard risk, high risk) of underlying disease, (2) sex, (3) year in which the transplantation was received, and (4) a 1:4 ratio of case-control. No factors were found to be associated with primary PGF. Compared to cases with good graft function, patients with primary PGF experienced poor overall survival (34.6 vs. 82.7 %, p < 0.001). Of the 26 primary PGF patients, only nine achieved hematopoietic recovery and survived. In conclusion, primary PGF is a rare but life-threatening complication after haploidentical SCT, and effective therapies need to be explored.

  8. Synergism of Cytotoxic T Lymphocyte–Associated Antigen 4 Blockade and Depletion of Cd25+ Regulatory T Cells in Antitumor Therapy Reveals Alternative Pathways for Suppression of Autoreactive Cytotoxic T Lymphocyte Responses

    PubMed Central

    Sutmuller, Roger P.M.; van Duivenvoorde, Leonie M.; van Elsas, Andrea; Schumacher, Ton N.M.; Wildenberg, Manon E.; Allison, James P.; Toes, Rene E.M.; Offringa, Rienk; Melief, Cornelis J.M.

    2001-01-01

    Therapeutic efficacy of a tumor cell–based vaccine against experimental B16 melanoma requires the disruption of either of two immunoregulatory mechanisms that control autoreactive T cell responses: the cytotoxic T lymphocyte–associated antigen (CTLA)-4 pathway or the CD25+ regulatory T (Treg) cells. Combination of CTLA-4 blockade and depletion of CD25+ Treg cells results in maximal tumor rejection. Efficacy of the antitumor therapy correlates with the extent of autoimmune skin depigmentation as well as with the frequency of tyrosinase-related protein 2180–188–specific CTLs detected in the periphery. Furthermore, tumor rejection is dependent on the CD8+ T cell subset. Our data demonstrate that the CTL response against melanoma antigens is an important component of the therapeutic antitumor response and that the reactivity of these CTLs can be augmented through interference with immunoregulatory mechanisms. The synergism in the effects of CTLA-4 blockade and depletion of CD25+ Treg cells indicates that CD25+ Treg cells and CTLA-4 signaling represent two alternative pathways for suppression of autoreactive T cell immunity. Simultaneous intervention with both regulatory mechanisms is therefore a promising concept for the induction of therapeutic antitumor immunity. PMID:11560997

  9. Partial regulatory T cell depletion prior to acute feline immunodeficiency virus infection does not alter disease pathogenesis.

    PubMed

    Mikkelsen, S Rochelle; Long, Julie M; Zhang, Lin; Galemore, Erin R; VandeWoude, Sue; Dean, Gregg A

    2011-02-25

    Feline immunodeficiency virus (FIV) infection in cats follows a disease course similar to HIV-1, including a short acute phase characterized by high viremia, and a prolonged asymptomatic phase characterized by low viremia and generalized immune dysfunction. CD4(+)CD25(hi)FoxP3(+) immunosuppressive regulatory T (Treg) cells have been implicated as a possible cause of immune dysfunction during FIV and HIV-1 infection, as they are capable of modulating virus-specific and inflammatory immune responses. Additionally, the immunosuppressive capacity of feline Treg cells has been shown to be increased during FIV infection. We have previously shown that transient in vivo Treg cell depletion during asymptomatic FIV infection reveals FIV-specific immune responses suppressed by Treg cells. In this study, we sought to determine the immunological influence of Treg cells during acute FIV infection. We asked whether Treg cell depletion prior to infection with the highly pathogenic molecular clone FIV-C36 in cats could alter FIV pathogenesis. We report here that partial Treg cell depletion prior to FIV infection does not significantly change provirus, viremia, or CD4(+) T cell levels in blood and lymphoid tissues during the acute phase of disease. The effects of anti-CD25 mAb treatment are truncated in cats acutely infected with FIV-C36 as compared to chronically infected cats or FIV-naïve cats, as Treg cell levels were heightened in all treatment groups included in the study within two weeks post-FIV infection. Our findings suggest that the influence of Treg cell suppression during FIV pathogenesis is most prominent after Treg cells are activated in the environment of established FIV infection.

  10. CD127 and CD25 Expression Defines CD4+ T Cell Subsets That Are Differentially Depleted during HIV Infection1

    PubMed Central

    Dunham, Richard M.; Cervasi, Barbara; Brenchley, Jason M.; Albrecht, Helmut; Weintrob, Amy; Sumpter, Beth; Engram, Jessica; Gordon, Shari; Klatt, Nichole R.; Frank, Ian; Sodora, Donald L.; Douek, Daniel C.; Paiardini, Mirko; Silvestri, Guido

    2009-01-01

    Decreased CD4+ T cell counts are the best marker of disease progression during HIV infection. However, CD4+ T cells are heterogeneous in phenotype and function, and it is unknown how preferential depletion of specific CD4+ T cell subsets influences disease severity. CD4+ T cells can be classified into three subsets by the expression of receptors for two T cell-tropic cytokines, IL-2 (CD25) and IL-7 (CD127). The CD127+CD25low/− subset includes IL-2-producing naive and central memory T cells; the CD127−CD25− subset includes mainly effector T cells expressing perforin and IFN-γ; and the CD127lowCD25high subset includes FoxP3-expressing regulatory T cells. Herein we investigated how the proportions of these T cell subsets are changed during HIV infection. When compared with healthy controls, HIV-infected patients show a relative increase in CD4+CD127−CD25− T cells that is related to an absolute decline of CD4+CD127+CD25low/− T cells. Interestingly, this expansion of CD4+CD127− T cells was not observed in naturally SIV-infected sooty mangabeys. The relative expansion of CD4+CD127−CD25− T cells correlated directly with the levels of total CD4+ T cell depletion and immune activation. CD4+CD127−CD25− T cells were not selectively resistant to HIV infection as levels of cell-associated virus were similar in all non-naive CD4+ T cell subsets. These data indicate that, during HIV infection, specific changes in the fraction of CD4+ T cells expressing CD25 and/or CD127 are associated with disease progression. Further studies will determine whether monitoring the three subsets of CD4+ T cells defined based on the expression of CD25 and CD127 should be used in the clinical management of HIV-infected individuals. PMID:18390743

  11. NK Cells and Other Innate Lymphoid Cells in Hematopoietic Stem Cell Transplantation.

    PubMed

    Vacca, Paola; Montaldo, Elisa; Croxatto, Daniele; Moretta, Francesca; Bertaina, Alice; Vitale, Chiara; Locatelli, Franco; Mingari, Maria Cristina; Moretta, Lorenzo

    2016-01-01

    Natural killer (NK) cells play a major role in the T-cell depleted haploidentical hematopoietic stem cell transplantation (haplo-HSCT) to cure high-risk leukemias. NK cells belong to the expanding family of innate lymphoid cells (ILCs). At variance with NK cells, the other ILC populations (ILC1/2/3) are non-cytolytic, while they secrete different patterns of cytokines. ILCs provide host defenses against viruses, bacteria, and parasites, drive lymphoid organogenesis, and contribute to tissue remodeling. In haplo-HSCT patients, the extensive T-cell depletion is required to prevent graft-versus-host disease (GvHD) but increases risks of developing a wide range of life-threatening infections. However, these patients may rely on innate defenses that are reconstituted more rapidly than the adaptive ones. In this context, ILCs may represent important players in the early phases following transplantation. They may contribute to tissue homeostasis/remodeling and lymphoid tissue reconstitution. While the reconstitution of NK cell repertoire and its role in haplo-HSCT have been largely investigated, little information is available on ILCs. Of note, CD34(+) cells isolated from different sources of HSC may differentiate in vitro toward various ILC subsets. Moreover, cytokines released from leukemia blasts (e.g., IL-1β) may alter the proportions of NK cells and ILC3, suggesting the possibility that leukemia may skew the ILC repertoire. Further studies are required to define the timing of ILC development and their potential protective role after HSCT.

  12. Both cladribine and alemtuzumab may effect MS via B-cell depletion.

    PubMed

    Baker, David; Herrod, Samuel S; Alvarez-Gonzalez, Cesar; Zalewski, Lukasz; Albor, Christo; Schmierer, Klaus

    2017-07-01

    To understand the efficacy of cladribine (CLAD) treatment in MS through analysis of lymphocyte subsets collected, but not reported, in the pivotal phase III trials of cladribine and alemtuzumab induction therapies. The regulatory submissions of the CLAD Tablets Treating Multiple Sclerosis Orally (CLARITY) (NCT00213135) cladribine and Comparison of Alemtuzumab and Rebif Efficacy in Multiple Sclerosis, study one (CARE-MS I) (NCT00530348) alemtuzumab trials were obtained from the European Medicine Agency through Freedom of Information requests. Data were extracted and statistically analyzed. Either dose of cladribine (3.5 mg/kg; 5.25 mg/kg) tested in CLARITY reduced the annualized relapse rate to 0.16-0.18 over 96 weeks, and both doses were similarly effective in reducing the risk of MRI lesions and disability. Surprisingly, however, T-cell depletion was rather modest. Cladribine 3.5 mg/kg depleted CD4 + cells by 40%-45% and CD8 + cells by 15%-30%, whereas alemtuzumab suppressed CD4 + cells by 70%-95% and CD8 + cells by 47%-55%. However, either dose of cladribine induced 70%-90% CD19 + B-cell depletion, similar to alemtuzumab (90%). CD19 + cells slowly repopulated to 15%-25% of baseline before cladribine redosing. However, alemtuzumab induced hyperrepopulation of CD19 + B cells 6-12 months after infusion, which probably forms the substrate for B-cell autoimmunities associated with alemtuzumab. Cladribine induced only modest depletion of T cells, which may not be consistent with a marked influence on MS, based on previous CD4 + T-cell depletion studies. The therapeutic drug-response relationship with cladribine is more consistent with lasting B-cell depletion and, coupled with the success seen with monoclonal CD20 + depletion, suggests that B-cell suppression could be the major direct mechanism of action.

  13. Immunotherapy of murine retrovirus-induced acquired immunodeficiency by CD4 T regulatory cell depletion and PD-1 blockade.

    PubMed

    Li, Wen; Green, William R

    2011-12-01

    LP-BM5 retrovirus induces a complex disease featuring an acquired immunodeficiency syndrome termed murine AIDS (MAIDS) in susceptible strains of mice, such as C57BL/6 (B6). CD4 T helper effector cells are required for MAIDS induction and progression of viral pathogenesis. CD8 T cells are not needed for viral pathogenesis, but rather, are essential for protection from disease in resistant strains, such as BALB/c. We have discovered an immunodominant cytolytic T lymphocyte (CTL) epitope encoded in a previously unrecognized LP-BM5 retroviral alternative (+1 nucleotide [nt]) gag translational open reading frame. CTLs specific for this cryptic gag epitope are the basis of protection from LP-BM5-induced immunodeficiency in BALB/c mice, and the inability of B6 mice to mount an anti-gag CTL response appears critical to the initiation and progression of LP-BM5-induced MAIDS. However, uninfected B6 mice primed by LP-BM5-induced tumors can generate CTL responses to an LP-BM5 retrovirus infection-associated epitope(s) that is especially prevalent on such MAIDS tumor cells, indicating the potential to mount a protective CD8 T-cell response. Here, we utilized this LP-BM5 retrovirus-induced disease system to test whether modulation of normal immune down-regulatory mechanisms can alter retroviral pathogenesis. Thus, following in vivo depletion of CD4 T regulatory (Treg) cells and/or selective interruption of PD-1 negative signaling in the CD8 T-cell compartment, retroviral pathogenesis was significantly decreased, with the combined treatment of CD4 Treg cell depletion and PD-1 blockade working in a synergistic fashion to substantially reduce the induction of MAIDS.

  14. Naive T cells are dispensable for memory CD4+ T cell homeostasis in progressive simian immunodeficiency virus infection.

    PubMed

    Okoye, Afam A; Rohankhedkar, Mukta; Abana, Chike; Pattenn, Audrie; Reyes, Matthew; Pexton, Christopher; Lum, Richard; Sylwester, Andrew; Planer, Shannon L; Legasse, Alfred; Park, Byung S; Piatak, Michael; Lifson, Jeffrey D; Axthelm, Michael K; Picker, Louis J

    2012-04-09

    The development of AIDS in chronic HIV/simian immunodeficiency virus (SIV) infection has been closely linked to progressive failure of CD4(+) memory T cell (T(M)) homeostasis. CD4(+) naive T cells (T(N)) also decline in these infections, but their contribution to disease progression is less clear. We assessed the role of CD4(+) T(N) in SIV pathogenesis using rhesus macaques (RMs) selectively and permanently depleted of CD4(+) T(N) before SIV infection. CD4(+) T(N)-depleted and CD4(+) T(N)-repleted RMs were created by subjecting juvenile RMs to thymectomy versus sham surgery, respectively, followed by total CD4(+) T cell depletion and recovery from this depletion. Although thymectomized and sham-treated RMs manifested comparable CD4(+) T(M) recovery, only sham-treated RMs reconstituted CD4(+) T(N). CD4(+) T(N)-depleted RMs responded to SIVmac239 infection with markedly attenuated SIV-specific CD4(+) T cell responses, delayed SIVenv-specific Ab responses, and reduced SIV-specific CD8(+) T cell responses. However, CD4(+) T(N)-depleted and -repleted groups showed similar levels of SIV replication. Moreover, CD4(+) T(N) deficiency had no significant effect on CD4(+) T(M) homeostasis (either on or off anti-retroviral therapy) or disease progression. These data demonstrate that the CD4(+) T(N) compartment is dispensable for CD4(+) T(M) homeostasis in progressive SIV infection, and they confirm that CD4(+) T(M) comprise a homeostatically independent compartment that is intrinsically capable of self-renewal.

  15. Evaluation of accessory cell heterogeneity. I. Differential accessory cell requirement for T helper cell activation and for T-B cooperation.

    PubMed

    Ramila, G; Studer, S; Kennedy, M; Sklenar, I; Erb, P

    1985-01-01

    Several Ia+ tumor cell lines and peritoneal exudate macrophages were tested as accessory cells (AC) for the activation of antigen-specific T cells and for T-B cooperation. The macrophages and all the Ia+ tumor lines tested induced the release of lymphokines from T cells in a major histocompatibility complex (MHC)-restricted fashion and reconstituted the antibody responses of AC-depleted spleen cells or of purified T and B cells. However, only the normal macrophages but none of the tumor lines induced carrier-specific T helper (Th) cells which help B cells for specific antihapten antibody responses by linked recognition. For T-B cooperation accessory cells were also required, but in contrast to Th cell activation any type of Ia+ AC (e.g. macrophage or tumor line) was effective. Strong MHC-restriction between the lymphocytes and the AC was seen if antigen-pulsed AC were added into the AC-depleted T-B cooperation cultures. If the AC and antigen were concomitantly added to the AC-depleted T-B cultures, MHC-restriction was less obvious. Concanavalin A supernatant reconstituted the response of AC-depleted T-B cultures provided antigen-specific Th cells and the hapten-carrier conjugate were present. If, however, tumor line-activated T cells were added instead of macrophage-induced Th cells, no cooperation with B cells took place even in the presence of Con A supernatant. The results obtained demonstrate a differential AC requirement for the induction of Th cells depending on the differentiation stage of the Th cells.

  16. Development of Augmented Leukemia/Lymphoma-Specific T-Cell Immunotherapy for Deployment with Haploidentical, Hematompoietic Progenitor-Cell Transplant

    DTIC Science & Technology

    2008-05-01

    adoptive therapy using CD19- specific chimeric antigen receptor re-directed T cells for recurrent/refractory follicular lymphoma. Mol Ther...T- cell therapies for B- cell malignancies we have developed a chimeric antigen receptor (CAR) which when expressed on the cell surface redirects T...that both CD4+ and CD8+ T cells expressing CD19-specific chimeric antigen receptor (CAR) can be generated usmg a novel non-viral gene

  17. 5-Azacitidine Monotherapy Followed by Related Haploidentical Hematopoietic Stem Cell Transplantation Achieves Durable Remission in a Pediatric Patient With Acute Undifferentiated Leukemia Refractory to High-Dose Chemotherapy.

    PubMed

    Polishchuk, Veronika; Khazal, Sajad; Berulava, Giorgi; Roth, Michael; Mahadeo, Kris M

    2016-06-01

    Patients with acute leukemias of undifferentiated lineage (AUL) generally have guarded prognosis. Here, we describe the first reported pediatric patient with AUL refractory to high-dose chemotherapy who achieved clinical remission with ALL maintenance therapy and 5-azacitidine. His induction remission was followed by consolidation with reduced toxicity haploidentical hematopoietic stem cell transplant (HSCT). At 9 months post-HSCT, the patient is alive and in remission. This combination therapy of remission induction with ALL maintenance therapy and 5-azacitidine and consolidation with reduced toxicity haploidentical HSCT is novel and promising for patients who lack conventional donors and are not candidates for myeloablative therapy. © 2016 Wiley Periodicals, Inc.

  18. Non-myeloablative autologous haematopoietic stem cell transplantation expands regulatory cells and depletes IL-17 producing mucosal-associated invariant T cells in multiple sclerosis

    PubMed Central

    Abrahamsson, Sofia V.; Angelini, Daniela F.; Dubinsky, Amy N.; Morel, Esther; Oh, Unsong; Jones, Joanne L.; Carassiti, Daniele; Reynolds, Richard; Salvetti, Marco; Calabresi, Peter A.; Coles, Alasdair J.; Battistini, Luca; Martin, Roland; Burt, Richard K.

    2013-01-01

    Autologous haematopoietic stem cell transplantation has been tried as one experimental strategy for the treatment of patients with aggressive multiple sclerosis refractory to other immunotherapies. The procedure is aimed at ablating and repopulating the immune repertoire by sequentially mobilizing and harvesting haematopoietic stem cells, administering an immunosuppressive conditioning regimen, and re-infusing the autologous haematopoietic cell product. ‘Non-myeloablative’ conditioning regimens to achieve lymphocytic ablation without marrow suppression have been proposed to improve safety and tolerability. One trial with non-myeloablative autologous haematopoietic stem cell transplantation reported clinical improvement and inflammatory stabilization in treated patients with highly active multiple sclerosis. The aim of the present study was to understand the changes in the reconstituted immune repertoire bearing potential relevance to its mode of action. Peripheral blood was obtained from 12 patients with multiple sclerosis participating in the aforementioned trial and longitudinally followed for 2 years. We examined the phenotype and function of peripheral blood lymphocytes by cell surface or intracellular staining and multi-colour fluorescence activated cell sorting alone or in combination with proliferation assays. During immune reconstitution post-transplantation we observed significant though transient increases in the proportion of CD4+FoxP3+ T cells and CD56high natural killer cell subsets, which are cell subsets associated with immunoregulatory function. CD8+CD57+ cytotoxic T cells were persistently increased after therapy and were able to suppress CD4+ T cell proliferation with variable potency. In contrast, a CD161high proinflammatory CD8+ T cell subset was depleted at all time-points post-transplantation. Phenotypic characterization revealed that the CD161highCD8+ T cells were mucosal-associated invariant T cells, a novel cell population originating

  19. Suppression of IL-12p70 formation by IL-2 or following macrophage depletion causes T-cell autoreactivity leading to CNS demyelination in HSV-1-infected mice.

    PubMed

    Lee, Dhong Hyun; Zandian, Mandana; Kuo, Jane; Mott, Kevin R; Chen, Shuang; Arditi, Moshe; Ghiasi, Homayon

    2017-05-01

    We have established two mouse models of central nervous system (CNS) demyelination that differ from most other available models of multiple sclerosis (MS) in that they represent a mixture of viral and immune triggers. In the first model, ocular infection of different strains of mice with a recombinant HSV-1 that expresses murine IL-2 constitutively (HSV-IL-2) causes CNS demyelination. In the second model, depletion of macrophages causes CNS demyelination in mice that are ocularly infected with wild-type (WT) HSV-1. In the present study, we found that the demyelination in macrophage-intact mice infected with HSV-IL-2 was blocked by depletion of FoxP3-expressing cells, while concurrent depletion of macrophages restored demyelination. In contrast, demyelination was blocked in the macrophage-depleted mice infected with wild-type HSV-1 following depletion of FoxP3-expressing cells. In macrophage-depleted HSV-IL-2-infected mice, demyelination was associated with the activity of both CD4+ and CD8+ T cells, whereas in macrophage-depleted mice infected with WT HSV-1, demyelination was associated with CD4+ T cells. Macrophage depletion or infection with HSV-IL-2 caused an imbalance of T cells and TH1 responses as well as alterations in IL-12p35 and IL-12p40 but not other members of the IL-12 family or their receptors. Demyelination was blocked by adoptive transfer of macrophages that were infected with HSV-IL-12p70 or HSV-IL-12p40 but not by HSV-IL-12p35. These results indicate that suppression of IL-12p70 formation by IL-2 or following macrophage depletion causes T-cell autoreactivity leading to CNS demyelination in HSV-1-infected mice.

  20. Suppression of IL-12p70 formation by IL-2 or following macrophage depletion causes T-cell autoreactivity leading to CNS demyelination in HSV-1-infected mice

    PubMed Central

    Lee, Dhong Hyun; Zandian, Mandana; Mott, Kevin R.; Chen, Shuang

    2017-01-01

    We have established two mouse models of central nervous system (CNS) demyelination that differ from most other available models of multiple sclerosis (MS) in that they represent a mixture of viral and immune triggers. In the first model, ocular infection of different strains of mice with a recombinant HSV-1 that expresses murine IL-2 constitutively (HSV-IL-2) causes CNS demyelination. In the second model, depletion of macrophages causes CNS demyelination in mice that are ocularly infected with wild-type (WT) HSV-1. In the present study, we found that the demyelination in macrophage-intact mice infected with HSV-IL-2 was blocked by depletion of FoxP3-expressing cells, while concurrent depletion of macrophages restored demyelination. In contrast, demyelination was blocked in the macrophage-depleted mice infected with wild-type HSV-1 following depletion of FoxP3-expressing cells. In macrophage-depleted HSV-IL-2-infected mice, demyelination was associated with the activity of both CD4+ and CD8+ T cells, whereas in macrophage-depleted mice infected with WT HSV-1, demyelination was associated with CD4+ T cells. Macrophage depletion or infection with HSV-IL-2 caused an imbalance of T cells and TH1 responses as well as alterations in IL-12p35 and IL-12p40 but not other members of the IL-12 family or their receptors. Demyelination was blocked by adoptive transfer of macrophages that were infected with HSV-IL-12p70 or HSV-IL-12p40 but not by HSV-IL-12p35. These results indicate that suppression of IL-12p70 formation by IL-2 or following macrophage depletion causes T-cell autoreactivity leading to CNS demyelination in HSV-1-infected mice. PMID:28542613

  1. Profound CD4+/CCR5+ T cell expansion is induced by CD8+ lymphocyte depletion but does not account for accelerated SIV pathogenesis

    PubMed Central

    Okoye, Afam; Park, Haesun; Rohankhedkar, Mukta; Coyne-Johnson, Lia; Lum, Richard; Walker, Joshua M.; Planer, Shannon L.; Legasse, Alfred W.; Sylwester, Andrew W.; Piatak, Michael; Lifson, Jeffrey D.; Sodora, Donald L.; Villinger, Francois; Axthelm, Michael K.; Schmitz, Joern E.

    2009-01-01

    Depletion of CD8+ lymphocytes during acute simian immunodeficiency virus (SIV) infection of rhesus macaques (RMs) results in irreversible prolongation of peak-level viral replication and rapid disease progression, consistent with a major role for CD8+ lymphocytes in determining postacute-phase viral replication set points. However, we report that CD8+ lymphocyte depletion is also associated with a dramatic induction of proliferation among CD4+ effector memory T (TEM) cells and, to a lesser extent, transitional memory T (TTrM) cells, raising the question of whether an increased availability of optimal (activated/proliferating), CD4+/CCR5+ SIV “target” cells contributes to this accelerated pathogenesis. In keeping with this, depletion of CD8+ lymphocytes in SIV− RMs led to a sustained increase in the number of potential CD4+ SIV targets, whereas such depletion in acute SIV infection led to increased target cell consumption. However, we found that the excess CD4+ TEM cell proliferation of CD8+ lymphocyte–depleted, acutely SIV-infected RMs was completely inhibited by interleukin (IL)-15 neutralization, and that this inhibition did not abrogate the rapidly progressive infection in these RMs. Moreover, although administration of IL-15 during acute infection induced robust CD4+ TEM and TTrM cell proliferation, it did not recapitulate the viral dynamics of CD8+ lymphocyte depletion. These data suggest that CD8+ lymphocyte function has a larger impact on the outcome of acute SIV infection than the number and/or activation status of target cells available for infection and viral production. PMID:19546246

  2. Blocking Virus Replication during Acute Murine Cytomegalovirus Infection Paradoxically Prolongs Antigen Presentation and Increases the CD8+ T Cell Response by Preventing Type I IFN-Dependent Depletion of Dendritic Cells.

    PubMed

    Loo, Christopher P; Snyder, Christopher M; Hill, Ann B

    2017-01-01

    Increasing amounts of pathogen replication usually lead to a proportionate increase in size and effector differentiation of the CD8 + T cell response, which is attributed to increased Ag and inflammation. Using a murine CMV that is highly sensitive to the antiviral drug famciclovir to modulate virus replication, we found that increased virus replication drove increased effector CD8 + T cell differentiation, as expected. Paradoxically, however, increased virus replication dramatically decreased the size of the CD8 + T cell response to two immunodominant epitopes. The decreased response was due to type I IFN-dependent depletion of conventional dendritic cells and could be reproduced by specific depletion of dendritic cells from day 2 postinfection or by sterile induction of type I IFN. Increased virus replication and type I IFN specifically inhibited the response to two immunodominant epitopes that are known to be dependent on Ag cross-presented by DCs, but they did not inhibit the response to "inflationary" epitopes whose responses can be sustained by infected nonhematopoietic cells. Our results show that type I IFN can suppress CD8 + T cell responses to cross-presented Ag by depleting cross-presenting conventional dendritic cells. Copyright © 2016 by The American Association of Immunologists, Inc.

  3. Development of Augmented Leukemia/Lymphoma-Specific T-Cell Immunotherapy for Deployment with Haploidentical Hematopoietic Progenitor-Cell Transplant

    DTIC Science & Technology

    2009-05-01

    adoptive therapy using CD19-specific chimeric antigen receptor re-directed T cells for recurrent/refrctory follicular lymphoma...Beauty (SB) transposon/transposase system to express a CD19-specific chimeric antigen receptor (CAR). T cells that have undergone transposition...accomplished using genetic engineering to express a chimeric antigen receptor (CAR) to redirect the specificity of T cells for CD19 on malignant B cells

  4. Reactivation of Latent Tuberculosis in Cynomolgus Macaques Infected with SIV Is Associated with Early Peripheral T Cell Depletion and Not Virus Load

    PubMed Central

    Klein, Edwin; Janssen, Chris; Phuah, Jiayao; Sturgeon, Timothy J.; Montelaro, Ronald C.; Lin, Philana Ling; Flynn, JoAnne L.

    2010-01-01

    HIV-infected individuals with latent Mycobacterium tuberculosis (Mtb) infection are at significantly greater risk of reactivation tuberculosis (TB) than HIV-negative individuals with latent TB, even while CD4 T cell numbers are well preserved. Factors underlying high rates of reactivation are poorly understood and investigative tools are limited. We used cynomolgus macaques with latent TB co-infected with SIVmac251 to develop the first animal model of reactivated TB in HIV-infected humans to better explore these factors. All latent animals developed reactivated TB following SIV infection, with a variable time to reactivation (up to 11 months post-SIV). Reactivation was independent of virus load but correlated with depletion of peripheral T cells during acute SIV infection. Animals experiencing reactivation early after SIV infection (<17 weeks) had fewer CD4 T cells in the periphery and airways than animals reactivating in later phases of SIV infection. Co-infected animals had fewer T cells in involved lungs than SIV-negative animals with active TB despite similar T cell numbers in draining lymph nodes. Granulomas from these animals demonstrated histopathologic characteristics consistent with a chronically active disease process. These results suggest initial T cell depletion may strongly influence outcomes of HIV-Mtb co-infection. PMID:20224771

  5. Protective CD8 Memory T Cell Responses to Mouse Melanoma Are Generated in the Absence of CD4 T Cell Help

    PubMed Central

    Steinberg, Shannon M.; Zhang, Peisheng; Turk, Mary Jo

    2011-01-01

    Background We have previously demonstrated that temporary depletion of CD4 T cells in mice with progressive B16 melanoma, followed by surgical tumor excision, induces protective memory CD8 T cell responses to melanoma/melanocyte antigens. We also showed that persistence of these CD8 T cells is supported, in an antigen-dependent fashion, by concurrent autoimmune melanocyte destruction. Herein we explore the requirement of CD4 T cell help in priming and maintaining this protective CD8 T cell response to melanoma. Methodology and Principal Findings To induce melanoma/melanocyte antigen-specific CD8 T cells, B16 tumor bearing mice were depleted of regulatory T cells (Treg) by either temporary, or long-term continuous treatment with anti-CD4 (mAb clone GK1.5). Total depletion of CD4 T cells led to significant priming of IFN-γ-producing CD8 T cell responses to TRP-2 and gp100. Surprisingly, treatment with anti-CD25 (mAb clone PC61), to specifically deplete Treg cells while leaving help intact, was ineffective at priming CD8 T cells. Thirty to sixty days after primary tumors were surgically excised, mice completely lacking CD4 T cell help developed autoimmune vitiligo, and maintained antigen-specific memory CD8 T cell responses that were highly effective at producing cytokines (IFN-γ, TNF-α, and IL-2). Mice lacking total CD4 T cell help also mounted protection against re-challenge with B16 melanoma sixty days after primary tumor excision. Conclusions and Significance This work establishes that CD4 T cell help is dispensable for the generation of protective memory T cell responses to melanoma. Our findings support further use of CD4 T cell depletion therapy for inducing long-lived immunity to cancer. PMID:22046294

  6. Selecting the best haploidentical donor.

    PubMed

    McCurdy, Shannon R; Fuchs, Ephraim J

    2016-10-01

    The substantial evidence of the safety of human leukocyte antigen (HLA)-haploidentical (haplo) blood or marrow transplantation (BMT) has led to its increasing utilization. When prioritizing HLA-matched grafts, patients frequently have few or no donors from whom to choose. However, a given patient may have multiple suitable haplo donors. Therefore factors other than HLA-match become critical for selecting the best donor. We recommend a donor selection algorithm based on the donor-specific antibodies, ABO match, donor age, donor sex, and cytomegalovirus (CMV) serostatus match. Despite provocative initial evidence, further studies are warranted to determine whether there is any benefit to selecting a haplo donor based on the number of HLA-mismatches, natural killer cell alloreactivity, or the presence of non-inherited maternal HLA antigens. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Impact of ABO incompatibility on patients' outcome after haploidentical hematopoietic stem cell transplantation for acute myeloid leukemia - a report from the Acute Leukemia Working Party of the EBMT.

    PubMed

    Canaani, Jonathan; Savani, Bipin N; Labopin, Myriam; Huang, Xiao-Jun; Ciceri, Fabio; Arcese, William; Tischer, Johanna; Koc, Yener; Bruno, Benedetto; Gülbas, Zafer; Blaise, Didier; Maertens, Johan; Ehninger, Gerhard; Mohty, Mohamad; Nagler, Arnon

    2017-06-01

    A significant proportion of hematopoietic stem cell transplants are performed with ABO-mismatched donors. The impact of ABO mismatch on outcome following transplantation remains controversial and there are no published data regarding the impact of ABO mismatch in acute myeloid leukemia patients receiving haploidentical transplants. Using the European Blood and Marrow Transplant Acute Leukemia Working Group registry we identified 837 patients who underwent haploidentical transplantation. Comparative analysis was performed between patients who received ABO-matched versus ABO-mismatched haploidentical transplants for common clinical outcome variables. Our cohort consisted of 522 ABO-matched patients and 315 ABO-mismatched patients including 150 with minor, 127 with major, and 38 with bi-directional ABO mismatching. There were no significant differences between ABO matched and mismatched patients in terms of baseline disease and clinical characteristics. Major ABO mismatching was associated with inferior day 100 engraftment rate whereas multivariate analysis showed that bi-directional mismatching was associated with increased risk of grade II-IV acute graft- versus -host disease [hazard ratio (HR) 2.387; 95% confidence interval (CI): 1.22-4.66; P =0.01). Non-relapse mortality, relapse incidence, leukemia-free survival, overall survival, and chronic graft- versus -host disease rates were comparable between ABO-matched and -mismatched patients. Focused analysis on stem cell source showed that patients with minor mismatching transplanted with bone marrow grafts experienced increased grade II-IV acute graft- versus -host disease rates (HR 2.03; 95% CI: 1.00-4.10; P =0.04). Patients with major ABO mismatching and bone marrow grafts had decreased survival (HR=1.82; CI 95%: 1.048 - 3.18; P =0.033). In conclusion, ABO incompatibility has a marginal but significant clinical effect in acute myeloid leukemia patients undergoing haploidentical transplantation. Copyright© Ferrata

  8. Impact of ABO incompatibility on patients’ outcome after haploidentical hematopoietic stem cell transplantation for acute myeloid leukemia - a report from the Acute Leukemia Working Party of the EBMT

    PubMed Central

    Canaani, Jonathan; Savani, Bipin N; Labopin, Myriam; Huang, Xiao-jun; Ciceri, Fabio; Arcese, William; Tischer, Johanna; Koc, Yener; Bruno, Benedetto; Gülbas, Zafer; Blaise, Didier; Maertens, Johan; Ehninger, Gerhard; Mohty, Mohamad; Nagler, Arnon

    2017-01-01

    A significant proportion of hematopoietic stem cell transplants are performed with ABO-mismatched donors. The impact of ABO mismatch on outcome following transplantation remains controversial and there are no published data regarding the impact of ABO mismatch in acute myeloid leukemia patients receiving haploidentical transplants. Using the European Blood and Marrow Transplant Acute Leukemia Working Group registry we identified 837 patients who underwent haploidentical transplantation. Comparative analysis was performed between patients who received ABO-matched versus ABO-mismatched haploidentical transplants for common clinical outcome variables. Our cohort consisted of 522 ABO-matched patients and 315 ABO-mismatched patients including 150 with minor, 127 with major, and 38 with bi-directional ABO mismatching. There were no significant differences between ABO matched and mismatched patients in terms of baseline disease and clinical characteristics. Major ABO mismatching was associated with inferior day 100 engraftment rate whereas multivariate analysis showed that bi-directional mismatching was associated with increased risk of grade II–IV acute graft-versus-host disease [hazard ratio (HR) 2.387; 95% confidence interval (CI): 1.22–4.66; P=0.01). Non-relapse mortality, relapse incidence, leukemia-free survival, overall survival, and chronic graft-versus-host disease rates were comparable between ABO-matched and -mismatched patients. Focused analysis on stem cell source showed that patients with minor mismatching transplanted with bone marrow grafts experienced increased grade II–IV acute graft-versus-host disease rates (HR 2.03; 95% CI: 1.00–4.10; P=0.04). Patients with major ABO mismatching and bone marrow grafts had decreased survival (HR=1.82; CI 95%: 1.048 – 3.18; P=0.033). In conclusion, ABO incompatibility has a marginal but significant clinical effect in acute myeloid leukemia patients undergoing haploidentical transplantation. PMID:28255020

  9. Depletion of Saccharomyces cerevisiae tRNAHis Guanylyltransferase Thg1p Leads to Uncharged tRNAHis with Additional m5C

    PubMed Central

    Gu, Weifeng; Hurto, Rebecca L.; Hopper, Anita K.; Grayhack, Elizabeth J.; Phizicky, Eric M.

    2005-01-01

    The essential Saccharomyces cerevisiae tRNAHis guanylyltransferase (Thg1p) is responsible for the unusual G−1 addition to the 5′ end of cytoplasmic tRNAHis. We report here that tRNAHis from Thg1p-depleted cells is uncharged, although histidyl tRNA synthetase is active and the 3′ end of the tRNA is intact, suggesting that G−1 is a critical determinant for aminoacylation of tRNAHis in vivo. Thg1p depletion leads to activation of the GCN4 pathway, most, but not all, of which is Gcn2p dependent, and to the accumulation of tRNAHis in the nucleus. Surprisingly, tRNAHis in Thg1p-depleted cells accumulates additional m5C modifications, which are delayed relative to the loss of G−1 and aminoacylation. The additional modification is likely due to tRNA m5C methyltransferase Trm4p. We developed a new method to map m5C residues in RNA and localized the additional m5C to positions 48 and 50. This is the first documented example of the accumulation of additional modifications in a eukaryotic tRNA species. PMID:16135808

  10. Reconstitution of lymphocyte subpopulations after hematopoietic stem cell transplantation: comparison of hematologic malignancies and donor types in event-free patients.

    PubMed

    Park, Borae G; Park, Chan-Jeoung; Jang, Seongsoo; Chi, Hyun-Sook; Kim, Dae-Young; Lee, Jung-Hee; Lee, Je-Hwan; Lee, Kyoo-Hyung

    2015-12-01

    The reconstitution of different immunocyte subsets after hematopoietic stem cell transplantation (HSCT), follows different timelines. We prospectively investigated changes in lymphocyte subsets after HSCT and their associations with primary diagnosis, conditioning regimen, and HSCT type in event-free patients. A total of 95 patients (48 with acute myeloid leukemia, 22 with acute lymphoid leukemia, and 25 with myelodysplastic syndrome) who underwent allogeneic HSCT (34 sibling matched, 37 unrelated matched, and 24 haploidentical HSCT) but did not experience any events such as relapse or death were enrolled in this study. Lymphocyte subpopulations (T cells, helper/inducer T cells, cytotoxic/suppressor T cells, memory T cells, regulatory T cells, natural killer (NK) cells, NK-T cells, and B cells) were quantified by flow cytometry of peripheral blood from recipients 7 days before and 1, 2, 3, 6, and 12 months after HSCT. Leukocyte counts recovered within 1 month after HSCT. However, the number of T and B lymphocytes recovered at 2 months after HSCT. NK cell counts recovered shortly after haploidentical HSCT. However, T lymphocytes and their subpopulations showed delayed recovery after haploidentical HSCT. Lymphocyte subsets showed different sequential patterns according to HSCT type but no differences were seen according to primary diagnosis or conditioning regimen. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. A highly relevant and efficient single step method for simultaneous depletion and isolation of human regulatory T cells in a clinical setting.

    PubMed

    Brezar, Vedran; Ruffin, Nicolas; Lévy, Yves; Seddiki, Nabila

    2014-09-01

    Regulatory T cells (Tregs) are pivotal in preventing autoimmunity. They play a major but still ambiguous role in cancer and viral infections. Functional studies of human Tregs are often hampered by numerous technical difficulties arising from imperfections in isolating and depleting protocols, together with the usual low cell number available from clinical samples. We standardized a simple procedure (Single Step Method, SSM), based on magnetic beads technology, in which both depletion and isolation of human Tregs with high purities are simultaneously achieved. SSM is suitable when using low cell numbers either fresh or frozen from both patients and healthy individuals. It allows simultaneous Tregs isolation and depletion that can be used for further functional work to monitor suppressive function of isolated Tregs (in vitro suppression assay) and also effector IFN-γ responses of Tregs-depleted cell fraction (OX40 assay). To our knowledge, there is no accurate standardized method for Tregs isolation and depletion in a clinical context. SSM could thus be used and easily standardized across different laboratories. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Human memory CD8 T cell effector potential is epigenetically preserved during in vivo homeostasis.

    PubMed

    Abdelsamed, Hossam A; Moustaki, Ardiana; Fan, Yiping; Dogra, Pranay; Ghoneim, Hazem E; Zebley, Caitlin C; Triplett, Brandon M; Sekaly, Rafick-Pierre; Youngblood, Ben

    2017-06-05

    Antigen-independent homeostasis of memory CD8 T cells is vital for sustaining long-lived T cell-mediated immunity. In this study, we report that maintenance of human memory CD8 T cell effector potential during in vitro and in vivo homeostatic proliferation is coupled to preservation of acquired DNA methylation programs. Whole-genome bisulfite sequencing of primary human naive, short-lived effector memory (T EM ), and longer-lived central memory (T CM ) and stem cell memory (T SCM ) CD8 T cells identified effector molecules with demethylated promoters and poised for expression. Effector-loci demethylation was heritably preserved during IL-7- and IL-15-mediated in vitro cell proliferation. Conversely, cytokine-driven proliferation of T CM and T SCM memory cells resulted in phenotypic conversion into T EM cells and was coupled to increased methylation of the CCR7 and Tcf7 loci. Furthermore, haploidentical donor memory CD8 T cells undergoing in vivo proliferation in lymphodepleted recipients also maintained their effector-associated demethylated status but acquired T EM -associated programs. These data demonstrate that effector-associated epigenetic programs are preserved during cytokine-driven subset interconversion of human memory CD8 T cells. © 2017 Abdelsamed et al.

  13. Donor CTLA-4 genotype influences clinical outcome after T cell-depleted allogeneic hematopoietic stem cell transplantation from HLA-identical sibling donors.

    PubMed

    Bosch-Vizcaya, Anna; Pérez-García, Arianne; Brunet, Salut; Solano, Carlos; Buño, Ismael; Guillem, Vicent; Martínez-Laperche, Carolina; Sanz, Guillermo; Barrenetxea, Cristina; Martínez, Carmen; Tuset, Esperanza; Lloveras, Natàlia; Coll, Rosa; Guardia, Ramon; González, Yolanda; Roncero, Josep M; Bustins, Anna; Gardella, Santiago; Fernández, Cristalina; Buch, Joan; Gallardo, David

    2012-01-01

    CTLA-4 (cytotoxic T-lymphocyte antigen-4) plays a pivotal role in inhibiting T cell activation through competitive interaction with B7 molecules and interruption of costimulatory signals mediated by CD28. Polymorphisms on the CTLA-4 gene have been previously associated with autoimmune diseases, predisposition to leukemic relapse, and with graft-versus-host disease (GVHD) or relapse after allogeneic transplant. As CTLA-4 is expressed on T-lymphocytes, the aim of this study was to determine whether the donor CTLA-4 CT60 genotype also influences clinical outcome even after T cell depletion with CD34-positive selection. We studied 136 patient-donor pairs. Overall survival (OS) was worse for those patients who received grafts from a donor with the CT60 AA genotype rather than from a donor with the AG or GG genotype (35.6% vs 49.4%; P = .043). This association was confirmed through multivariate analysis, which identified the donor CT60 genotype as an independent risk factor for OS (P = .008; hazard ratio [HR]: 2.24, 95% confidence interval [CI]: 1.23-4.08). The donor CT60 AA genotype was also associated with lower disease-free survival, this being related to an increased risk of relapse (P = .001; HR: 3.41, 95% CI: 1.67-6.96) and a trend toward higher transplant-related mortality. These associations were stronger when considering only patients in the early stage of disease. Our results suggest that graft-versus-leukemia (GVL) activity after T cell depletion is conditioned by the donor CTLA-4 genotype. Copyright © 2012 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  14. T Cell Depletion for Recipients of HLA Haploidentical Related Donor Stem Cell Grafts

    ClinicalTrials.gov

    2017-08-29

    Acute Lymphoblastic Leukemia; Non Hodgkins Lymphoma; Myelodysplastic Syndrome; Acute Myeloid Leukemia; Chronic Myelogenous Leukemia; Hemophagocytic Lymphohistiocytosis (HLH); Familial Hemophagocytic Lymphohistiocytosis (FLH); Viral-associated Hemophagocytic Syndrome (VAHS); X-linked Lymphoproliferative Disease (XLP)

  15. Naive T cells are dispensable for memory CD4+ T cell homeostasis in progressive simian immunodeficiency virus infection

    PubMed Central

    Okoye, Afam A.; Rohankhedkar, Mukta; Abana, Chike; Pattenn, Audrie; Reyes, Matthew; Pexton, Christopher; Lum, Richard; Sylwester, Andrew; Planer, Shannon L.; Legasse, Alfred; Park, Byung S.; Piatak, Michael; Lifson, Jeffrey D.; Axthelm, Michael K.

    2012-01-01

    The development of AIDS in chronic HIV/simian immunodeficiency virus (SIV) infection has been closely linked to progressive failure of CD4+ memory T cell (TM) homeostasis. CD4+ naive T cells (TN) also decline in these infections, but their contribution to disease progression is less clear. We assessed the role of CD4+ TN in SIV pathogenesis using rhesus macaques (RMs) selectively and permanently depleted of CD4+ TN before SIV infection. CD4+ TN-depleted and CD4+ TN-repleted RMs were created by subjecting juvenile RMs to thymectomy versus sham surgery, respectively, followed by total CD4+ T cell depletion and recovery from this depletion. Although thymectomized and sham-treated RMs manifested comparable CD4+ TM recovery, only sham-treated RMs reconstituted CD4+ TN. CD4+ TN-depleted RMs responded to SIVmac239 infection with markedly attenuated SIV-specific CD4+ T cell responses, delayed SIVenv-specific Ab responses, and reduced SIV-specific CD8+ T cell responses. However, CD4+ TN-depleted and -repleted groups showed similar levels of SIV replication. Moreover, CD4+ TN deficiency had no significant effect on CD4+ TM homeostasis (either on or off anti-retroviral therapy) or disease progression. These data demonstrate that the CD4+ TN compartment is dispensable for CD4+ TM homeostasis in progressive SIV infection, and they confirm that CD4+ TM comprise a homeostatically independent compartment that is intrinsically capable of self-renewal. PMID:22451717

  16. Haploidentical transplant with posttransplant cyclophosphamide vs matched unrelated donor transplant for acute myeloid leukemia

    PubMed Central

    Zhang, Mei-Jie; Bacigalupo, Andrea A.; Bashey, Asad; Appelbaum, Frederick R.; Aljitawi, Omar S.; Armand, Philippe; Antin, Joseph H.; Chen, Junfang; Devine, Steven M.; Fowler, Daniel H.; Luznik, Leo; Nakamura, Ryotaro; O’Donnell, Paul V.; Perales, Miguel-Angel; Pingali, Sai Ravi; Porter, David L.; Riches, Marcie R.; Ringdén, Olle T. H.; Rocha, Vanderson; Vij, Ravi; Weisdorf, Daniel J.; Champlin, Richard E.; Horowitz, Mary M.; Fuchs, Ephraim J.; Eapen, Mary

    2015-01-01

    We studied adults with acute myeloid leukemia (AML) after haploidentical (n = 192) and 8/8 HLA-matched unrelated donor (n = 1982) transplantation. Haploidentical recipients received calcineurin inhibitor (CNI), mycophenolate, and posttransplant cyclophosphamide for graft-versus-host disease (GVHD) prophylaxis; 104 patients received myeloablative and 88 received reduced intensity conditioning regimens. Matched unrelated donor transplant recipients received CNI with mycophenolate or methotrexate for GVHD prophylaxis; 1245 patients received myeloablative and 737 received reduced intensity conditioning regimens. In the myeloablative setting, day 30 neutrophil recovery was lower after haploidentical compared with matched unrelated donor transplants (90% vs 97%, P = .02). Corresponding rates after reduced intensity conditioning transplants were 93% and 96% (P = .25). In the myeloablative setting, 3-month acute grade 2-4 (16% vs 33%, P < .0001) and 3-year chronic GVHD (30% vs 53%, P < .0001) were lower after haploidentical compared with matched unrelated donor transplants. Similar differences were observed after reduced intensity conditioning transplants, 19% vs 28% (P = .05) and 34% vs 52% (P = .002). Among patients receiving myeloablative regimens, 3-year probabilities of overall survival were 45% (95% CI, 36-54) and 50% (95% CI, 47-53) after haploidentical and matched unrelated donor transplants (P = .38). Corresponding rates after reduced intensity conditioning transplants were 46% (95% CI, 35-56) and 44% (95% CI, 0.40-47) (P = .71). Although statistical power is limited, these data suggests that survival for patients with AML after haploidentical transplantation with posttransplant cyclophosphamide is comparable with matched unrelated donor transplantation. PMID:26130705

  17. Gamma Interferon-Induced T-Cell Loss in Virulent Mycobacterium avium Infection

    PubMed Central

    Flórido, Manuela; Pearl, John E.; Solache, Alejandra; Borges, Margarida; Haynes, Laura; Cooper, Andrea M.; Appelberg, Rui

    2005-01-01

    Infection by virulent Mycobacterium avium caused progressive severe lymphopenia in C57BL/6 mice due to increased apoptosis rates. T-cell depletion did not occur in gamma interferon (IFN-γ)-deficient mice which showed increased T-cell numbers and proliferation; in contrast, deficiency in nitric oxide synthase 2 did not prevent T-cell loss. Although T-cell loss was IFN-γ dependent, expression of the IFN-γ receptor on T cells was not required for depletion. Similarly, while T-cell loss was optimal if the T cells expressed IFN-γ, CD8+ T-cell depletion could occur in the absence of T-cell-derived IFN-γ. Depletion did not require that the T cells be specific for mycobacterial antigen and was not affected by deficiencies in the tumor necrosis factor receptors p55 or p75, the Fas receptor (CD95), or the respiratory burst enzymes or by forced expression of bcl-2 in hematopoietic cells. PMID:15908387

  18. Alternative allogeneic donor sources for transplantation for childhood diseases: unrelated cord blood and haploidentical family donors.

    PubMed

    Cairo, Mitchell S; Rocha, Vanderson; Gluckman, Eliane; Hale, Gregory; Wagner, John

    2008-01-01

    Allogeneic stem cell transplantation has been demonstrated to be curative in a wide variety of pediatric malignant and nonmalignant diseases, and can be traced back over 50 years ago to the original report of Thomas et al. HLA matched sibling donors have been the gold standard for pediatric recipients requiring allogeneic donors for both nonmalignant and malignant conditions. However, only 25% of potential pediatric recipients possesses an HLA-matched sibling donor, and the frequency is even less in those with genetic nonmalignant conditions because of genetically affected other siblings within the family. Therefore, 75% to 90% of potential pediatric recipients require alternative allogeneic donor cells for treatment of their underlying conditions. Potential alternative allogeneic donor sources include unrelated cord blood donors, unrelated adult donors, and haploidentical family donors. In this article we review the experience of both unrelated cord blood donor and haploidentical family donor transplants in selected pediatric malignant and nonmalignant conditions.

  19. The effect of regulatory T-cell depletion on the spectrum of organ-specific autoimmune diseases in nonobese diabetic mice at different ages.

    PubMed

    Nakahara, Mami; Nagayama, Yuji; Ichikawa, Tatsuki; Yu, Liping; Eisenbarth, George S; Abiru, Norio

    2011-09-01

    The nonobese diabetic (NOD) mouse spontaneously develops several autoimmune diseases, including type 1 diabetes and to a lesser extent thyroiditis and sialitis. Imbalance between effector T cells (Teffs) and regulatory T cells (Tregs) has recently been proposed as a mechanism for the disease pathogenesis in NOD mice, but previous studies have shown the various outcomes by different timing and methods of Treg-depletion. This study was, therefore, designed to compare the consequences of Treg-depletion by the same method (anti-CD25 antibody) on the spectrum of organ-specific autoimmune diseases in NOD mice of different ages. Treg-depletion by anti-CD25 antibody at 10 days of age accelerated development of all three diseases we examined (insulitis/diabetes, thyroiditis, and sialitis); Treg-depletion at 4 weeks of age accelerated only diabetes but not thyroiditis or sialitis; and Treg-depletion at 12 weeks of age hastened only development of thyroiditis and exhibited little influence on diabetes or sialitis. Increased levels of insulin autoantibodies (IAA) were, however, observed in mice depleted of Tregs at 10 days of age, not in those at 4 weeks. Thus, the consequences of Treg-depletion on the spectrum of organ-specific autoimmune diseases depend on the timing of anti-CD25 antibody injection in NOD mice. Aging gradually tips balance between Teffs and Tregs toward Teff-dominance for diabetes, but this balance for thyroiditis and sialitis likely alters more intricately. Our data also suggest that the levels of IAA are not necessarily correlated with diabetes development.

  20. CD19xCD3 DART protein mediates human B-cell depletion in vivo in humanized BLT mice

    PubMed Central

    Tsai, Perry; Thayer, William O; Liu, Liqin; Silvestri, Guido; Nordstrom, Jeffrey L; Garcia, J Victor

    2016-01-01

    Novel therapeutic strategies are needed for the treatment of hematologic malignancies; and bispecific antibody-derived molecules, such as dual-affinity re-targeting (DART) proteins, are being developed to redirect T cells to kill target cells expressing tumor or viral antigens. Here we present our findings of specific and systemic human B-cell depletion by a CD19xCD3 DART protein in humanized BLT mice. Administration of the CD19xCD3 DART protein resulted in a dramatic sustained depletion of human CD19+ B cells from the peripheral blood, as well as a dramatic systemic reduction of human CD19+ B-cell levels in all tissues (bone marrow, spleen, liver, lung) analyzed. When human CD8+ T cells were depleted from the mice, no significant B-cell depletion was observed in response to CD19xCD3 DART protein treatment, confirming that human CD8+ T cells are the primary effector cells in this in vivo model. These studies validate the use of BLT humanized mice for the in vivo evaluation and preclinical development of bispecific molecules that redirect human T cells to selectively deplete target cells. PMID:27119115

  1. CD4+CD73+ T cells are associated with lower T-cell activation and C reactive protein levels and are depleted in HIV-1 infection regardless of viral suppression

    PubMed Central

    Schuler, Patrick J.; Macatangay, Bernard J.C.; Saze, Zenichiro; Jackson, Edwin K.; Riddler, Sharon A.; Buchanan, William G.; Hilldorfer, Benedict B.; Mellors, John W.; Whiteside, Theresa L.; Rinaldo, Charles R.

    2013-01-01

    Background The role of the adenosine (ADO) suppression pathway, specifically CD39-expressing and CD73-expressing CD4+ T cells in HIV-1 infection is unclear. Methods We evaluated the frequency and numbers of CD4+CD39+ and CD4+CD73+ T cells, activated T cells, and plasma C reactive protein (CRP) levels in 36 HIV-1-positive individuals and 10 normal controls (NC). Low-level plasma viremia was evaluated using single copy assay. Mass spectrometry was used to measure hydrolysis of ATP by ectoenzyme-expressing CD4+ T cells, whereas cyclic adenosine monophosphate (cAMP) levels were measured using enzyme immunoassay. Suppression of T-cell function by exogenous ADO and CD4+CD73+ T cells was tested by flow cytometry. Results CD39 and CD73 are expressed in different CD4+ T-cell subsets. CD4+CD73+ T cells do not express CD25 and FOXP3, and their frequency and numbers were lower in HIV-1-positive individuals regardless of virologic suppression (P = 0.005 and P < 0.001, respectively). CD4+CD73+ numbers inversely correlated with CD4+CD38+DR+ (P = 0.002), CD8+CD38+DR+ T-cell frequency (P = 0.05), and plasma CRP levels (P = 0.01). Both subsets are required for hydrolysis of exogenous ATP to ADO and can increase CD4+ T-cell cAMP levels when incubated with exogenous ATP. Low-level viremia did not correlate with activated T-cell frequency. In vitro, ADO suppressed T-cell activation and cytokine expression. CD4+CD73+ T cells suppressed T-cell proliferation only in the presence of exogenous 5′-AMP. Conclusion The ADO-producing CD4+CD73+ subset of T cells is depleted in HIV-1-positive individuals regardless of viral suppression and may play a key role in controlling HIV-1-associated immune activation. PMID:24005375

  2. Acyclovir-resistant herpes simplex virus 1 infection early after allogeneic hematopoietic stem cell transplantation with T-cell depletion.

    PubMed

    Akahoshi, Yu; Kanda, Junya; Ohno, Ayumu; Komiya, Yusuke; Gomyo, Ayumi; Hayakawa, Jin; Harada, Naonori; Kameda, Kazuaki; Ugai, Tomotaka; Wada, Hidenori; Ishihara, Yuko; Kawamura, Koji; Sakamoto, Kana; Sato, Miki; Terasako-Saito, Kiriko; Kimura, Shun-Ichi; Kikuchi, Misato; Nakasone, Hideki; Kako, Shinichi; Shiraki, Kimiyasu; Kanda, Yoshinobu

    2017-07-01

    We previously reported that oral low-dose acyclovir (200 mg/day) for the prevention of herpes simplex virus (HSV) infections after allogenic hematopoietic stem cell transplantation (HSCT) is effective without the emergence of acyclovir-resistant HSV infections. However, HSV infections are of significant concern because the number of allogeneic HSCT with T-cell depletion, which is a risk factor of the emergence of drug-resistant HSV infections, has been increasing. We experienced a 25-year-old female who received allogenic HSCT from an unrelated donor with 1-antigen mismatch using anti-thymocyte globulin. Despite acyclovir prophylaxis (200 mg/day), she developed the right palatal ulcer that was positive for HSV-1 specific antigen by fluorescent antibody on day 20 and developed new hypoglossal and tongue ulcers on day 33. Replacement of acyclovir with foscarnet improved her ulcers. We isolated 2 acyclovir-resistant and foscarnet-sensitive strains from the right palatal and hypoglossal ulcers, which had the same frame shift mutation in the thymidine kinase genes. The rate of proliferation of the isolate from the hypoglossal ulcer was faster than that from the right palatal ulcer in the plaque reduction assay. HSV strains that acquired acyclovir-resistant mutations at the right palatal ulcer with larger plaque might spread to the hypoglossal ulcer as the secondary site of infection because of better growth property. Second-line antiviral agents should be considered when we suspect treatment failure of HSV infection, especially in HSCT with T-cell depletion. Further studies are required whether low-dose acyclovir prophylaxis leads to the emergence of virological resistance. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  3. Upfront haploidentical transplant for acquired severe aplastic anemia: registry-based comparison with matched related transplant.

    PubMed

    Xu, Lan-Ping; Jin, Song; Wang, Shun-Qing; Xia, Ling-Hui; Bai, Hai; Gao, Su-Jun; Liu, Qi-Fa; Wang, Jian-Min; Wang, Xin; Jiang, Ming; Zhang, Xi; Wu, De-Pei; Huang, Xiao-Jun

    2017-01-21

    Haploidentical donor (HID) hematopoietic stem cell transplantation (HSCT) is an alternative treatment method for severe aplastic anemia (SAA) patients lacking suitable identical donors and those who are refractory to immunosuppressive therapy (IST). The current study evaluated the feasibility of upfront haploidentical HSCT in SAA patients. We conducted a multicenter study based on a registry database. One hundred fifty-eight SAA patients who underwent upfront transplantation between June 2012 and September 2015 were enrolled. Eighty-nine patients had haploidentical donors (HIDs), and 69 had matched related donors (MRDs) for HSCT. The median times for myeloid engraftment in the HID and MRD cohorts were 12 (range, 9-20) and 11 (range, 8-19) days, with a cumulative incidence of 97.8 and 97.1% (P = 0.528), respectively. HID recipients had an increased cumulative incidence of grades II-IV acute graft-versus-host disease (aGVHD) (30.3 vs. 1.5%, P < 0.001), grades III-IV aGVHD (10.1 vs. 1.5%, P = 0.026), and chronic GVHD (cGVHD) (30.6 vs. 4.4%, P < 0.001) at 1 year but similar extensive cGVHD (3.4 vs. 0%, P = 0.426). The three-year estimated overall survival (OS) rates were 86.1 and 91.3% (P = 0.358), while the three-year estimated failure-free survival (FFS) rates were 85.0 and 89.8% (P = 0.413) in the HID and MRD cohorts, respectively. In multivariate analysis, survival outcome for the entire population was significantly adversely associated with increased transfusions and poor performance status pre-SCT. We did not observe differences in primary engraftment and survival outcomes by donor type. Haploidentical SCT as upfront therapy was an effective and safe option for SAA patients, with favorable outcomes in experienced centers.

  4. CD62L− memory T cells enhance T-cell regeneration after allogeneic stem cell transplantation by eliminating host resistance in mice

    PubMed Central

    Zhang, Jifeng; Barefoot, Brice E.; Mo, Wenjian; Deoliveira, Divino; Son, Jessica; Cui, Xiuyu; Ramsburg, Elizabeth

    2012-01-01

    A major challenge in allogeneic hematopoietic cell transplantation is how to transfer T-cell immunity without causing graft-versus-host disease (GVHD). Effector memory T cells (CD62L−) are a cell subset that can potentially address this challenge because they do not induce GVHD. Here, we investigated how CD62L− T cells contributed to phenotypic and functional T-cell reconstitution after transplantation. On transfer into allogeneic recipients, CD62L− T cells were activated and expressed multiple cytokines and cytotoxic molecules. CD62L− T cells were able to deplete host radioresistant T cells and facilitate hematopoietic engraftment, resulting in enhanced de novo T-cell regeneration. Enhanced functional immune reconstitution was demonstrated in CD62L− T-cell recipients using a tumor and an influenza virus challenge model. Even though CD62L− T cells are able to respond to alloantigens and deplete host radioresistant immune cells in GVHD recipients, alloreactive CD62L− T cells lost the reactivity over time and were eventually tolerant to alloantigens as a result of prolonged antigen exposure, suggesting a mechanism by which CD62L− T cells were able to eliminate host resistance without causing GVHD. These data further highlight the unique characteristics of CD62L− T cells and their potential applications in clinical hematopoietic cell transplantation. PMID:22596261

  5. Limited CD4+ T cell proliferation leads to preservation of CD4+ T cell counts in SIV-infected sooty mangabeys.

    PubMed

    Chan, Ming Liang; Petravic, Janka; Ortiz, Alexandra M; Engram, Jessica; Paiardini, Mirko; Cromer, Deborah; Silvestri, Guido; Davenport, Miles P

    2010-12-22

    Human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) infections result in chronic virus replication and progressive depletion of CD4+ T cells, leading to immunodeficiency and death. In contrast, 'natural hosts' of SIV experience persistent infection with high virus replication but no severe CD4+ T cell depletion, and remain AIDS-free. One important difference between pathogenic and non-pathogenic infections is the level of activation and proliferation of CD4+ T cells. We analysed the relationship between CD4+ T cell number and proliferation in HIV, pathogenic SIV in macaques, and non-pathogenic SIV in sooty mangabeys (SMs) and mandrills. We found that CD4+ T cell proliferation was negatively correlated with CD4+ T cell number, suggesting that animals respond to the loss of CD4+ T cells by increasing the proliferation of remaining cells. However, the level of proliferation seen in pathogenic infections (SIV in rhesus macaques and HIV) was much greater than in non-pathogenic infections (SMs and mandrills). We then used a modelling approach to understand how the host proliferative response to CD4+ T cell depletion may impact the outcome of infection. This modelling demonstrates that the rapid proliferation of CD4+ T cells in humans and macaques associated with low CD4+ T cell levels can act to 'fuel the fire' of infection by providing more proliferating cells for infection. Natural host species, on the other hand, have limited proliferation of CD4+ T cells at low CD4+ T cell levels, which allows them to restrict the number of proliferating cells susceptible to infection.

  6. HIV-1 Infection Is Associated with Depletion and Functional Impairment of Mycobacterium tuberculosis-Specific CD4 T Cells in Individuals with Latent Tuberculosis Infection.

    PubMed

    Day, Cheryl L; Abrahams, Deborah A; Harris, Levelle D; van Rooyen, Michele; Stone, Lynnett; de Kock, Marwou; Hanekom, Willem A

    2017-09-15

    Coinfection with HIV is the single greatest risk factor for reactivation of latent Mycobacterium tuberculosis infection (LTBI) and progression to active tuberculosis disease. HIV-associated dysregulation of adaptive immunity by depletion of CD4 Th cells most likely contributes to loss of immune control of LTBI in HIV-infected individuals, although the precise mechanisms whereby HIV infection impedes successful T cell-mediated control of M. tuberculosis have not been well defined. To further delineate mechanisms whereby HIV impairs protective immunity to M. tuberculosis , we evaluated the frequency, phenotype, and functional capacity of M. tuberculosis -specific CD4 T cells in HIV-infected and HIV-uninfected adults with LTBI. HIV infection was associated with a lower total frequency of cytokine-producing M. tuberculosis -specific CD4 T cells, and preferential depletion of a discrete subset of M. tuberculosis -specific IFN-γ + IL-2 - TNF-α + CD4 T cells. M. tuberculosis -specific CD4 T cells in HIV-infected individuals expressed significantly higher levels of Ki67, compared with HIV-uninfected individuals, thus indicating recent activation and turnover of these cells in vivo. The ex vivo proliferative capacity of M. tuberculosis -specific CD4 T cells was markedly impaired in HIV-infected individuals, compared with HIV-uninfected individuals. Moreover, HIV infection was associated with increased M. tuberculosis Ag-induced CD4 T cell death ex vivo, indicating a possible mechanism contributing to impaired proliferative capacity of M. tuberculosis -specific CD4 T cells in HIV-infected individuals. These data provide new insights into the parameters of M. tuberculosis -specific CD4 T cell immunity that are impaired in HIV-infected individuals with LTBI, which may contribute to their increased risk of developing active tuberculosis disease. Copyright © 2017 by The American Association of Immunologists, Inc.

  7. B-Cell Depletion Promotes Aortic Infiltration of Immunosuppressive Cells and Is Protective of Experimental Aortic Aneurysm.

    PubMed

    Schaheen, Basil; Downs, Emily A; Serbulea, Vlad; Almenara, Camila C P; Spinosa, Michael; Su, Gang; Zhao, Yunge; Srikakulapu, Prasad; Butts, Cherié; McNamara, Coleen A; Leitinger, Norbert; Upchurch, Gilbert R; Meher, Akshaya K; Ailawadi, Gorav

    2016-11-01

    B-cell depletion therapy is widely used for treatment of cancers and autoimmune diseases. B cells are abundant in abdominal aortic aneurysms (AAA); however, it is unknown whether B-cell depletion therapy affects AAA growth. Using experimental models of murine AAA, we aim to examine the effect of B-cell depletion on AAA formation. Wild-type or apolipoprotein E-knockout mice were treated with mouse monoclonal anti-CD20 or control antibodies and subjected to an elastase perfusion or angiotensin II infusion model to induce AAA, respectively. Anti-CD20 antibody treatment significantly depleted B1 and B2 cells, and strikingly suppressed AAA growth in both models. B-cell depletion resulted in lower circulating IgM levels, but did not affect the levels of IgG or cytokine/chemokine levels. Although the total number of leukocyte remained unchanged in elastase-perfused aortas after anti-CD20 antibody treatment, the number of B-cell subtypes was significantly lower. Interestingly, plasmacytoid dendritic cells expressing the immunomodulatory enzyme indole 2,3-dioxygenase were detected in the aortas of B-cell-depleted mice. In accordance with an increase in indole 2,3-dioxygenase+ plasmacytoid dendritic cells, the number of regulatory T cells was higher, whereas the expression of proinflammatory genes was lower in aortas of B-cell-depleted mice. In a coculture model, the presence of B cells significantly lowered the number of indole 2,3-dioxygenase+ plasmacytoid dendritic cells without affecting total plasmacytoid dendritic cell number. The present results demonstrate that B-cell depletion protects mice from experimental AAA formation and promotes emergence of an immunosuppressive environment in aorta. © 2016 American Heart Association, Inc.

  8. Sufficient Immunosuppression with Thymoglobulin Is Essential for a Successful Haplo-Myeloid Bridge in Haploidentical-Cord Blood Transplantation.

    PubMed

    Lindemans, Caroline A; Te Boome, Liane C J; Admiraal, Rick; Jol-van der Zijde, Els C; Wensing, Anne M; Versluijs, A Birgitta; Bierings, Marc B; Kuball, Jürgen; Boelens, Jaap J

    2015-10-01

    In haploidentical (haplo)-cord blood (CB) transplantations, early haplo donor engraftment serves as a myeloid bridge to sustainable CB engraftment and is associated with early neutrophil recovery. The conditioning regimens as published for haplo-cord protocols usually contain serotherapy, such as rabbit antithymocyte globulin (ATG) (Thymoglobulin, Genzyme, Cambridge, MA). However, reducing or omitting serotherapy is an important strategy to improve early immune reconstitution after transplantation. The need for serotherapy in successful haplo-cord transplantation, defined as having a haplo-derived myeloid bridge to CB engraftment, has not been investigated before. Two consecutive cohorts of patients underwent transplantation with haplo-CB. The first group underwent transplantation with haplo-CB for active infection and/or an underlying condition with expected difficult engraftment without a conventional donor available. They received a single unit (s) CB and haplo donor cells (CD34(+) selected, 5 × 10(6) CD34(+)/kg). The second cohort included patients with poor-risk malignancies, not eligible for other treatment protocols. They received a sCB and haplo donor cells (CD19/αβTCR-depleted; 5 × 10(6) CD34(+)/kg). Retrospectively in both cohorts, active ATG (Thymoglobulin) levels were measured and post-hematopoietic cell transplantation area under the curve (AUC) was calculated. The influence of ATG exposure for having a successful haplo-myeloid bridge (early haplo donor engraftment before CB engraftment and no secondary neutropenia) and transplantation-related mortality (TRM) were analyzed as primary endpoints. Twenty patients were included (16 in the first cohort and 4 in the second cohort). In 58% of evaluable patients, there was no successful haplo-derived myeloid bridge to CB engraftment, for which a low post-transplantation ATG exposure appeared to be a predictor (P <.001). TRM in the unsuccessful haplo-bridge group was 70% ± 16% versus 12% ± 12% in the

  9. Risk Factors for and the Clinical Impact of Cytomegalovirus and Epstein-Barr Virus Infections in Pediatric Recipients of TCR-α/β- and CD19-Depleted Grafts.

    PubMed

    Laberko, Alexandra; Bogoyavlenskaya, Anna; Shelikhova, Larisa; Shekhovtsova, Zhanna; Balashov, Dmitriy; Voronin, Kirill; Kurnikova, Elena; Boyakova, Elena; Raykina, Elena; Brilliantova, Varvara; Pirumova, Valentina; Novichkova, Galina; Maschan, Alexei; Maschan, Michael

    2017-03-01

    Alpha/beta T cell and CD19 depletion are used to improve the outcomes of hematopoietic stem cell transplantation (HSCT). We evaluated the burden of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) in pediatric patients after this HSCT type. A cohort of 182 patients with malignant (n = 114) or nonmalignant (n = 68) disorders was transplanted from either matched unrelated (n = 124) or haploidentical (n = 58) donors. The cumulative incidence of CMV and EBV viremia were 51% and 33%, respectively. Acute graft-versus-host disease (GVHD) grades II to IV, D-/R+ serology, and malignant HSCT indications were associated with increased risk of CMV viremia. CMV disease developed in 10 patients (6%). The occurrence of CMV viremia was not associated with inferior outcomes. Acute GVHD grade ≥ II was the only factor significantly associated with an increased risk of EBV viremia. Rituximab significantly decreased the rate of EBV reactivation in a subgroup that received a higher B cell dose in the graft. The rate of EBV-associated disease was .5%, and EBV viremia did not affect survival. TCR-α/β and CD19 depletion are associated with a significant rate of CMV viremia that does not affect survival. The hazard of EBV post-transplant lymphoproliferative disease (PTLD) is eliminated by the combination of CD19 depletion and rituximab. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  10. Antigen specific T-cell responses against tumor antigens are controlled by regulatory T cells in patients with prostate cancer.

    PubMed

    Hadaschik, Boris; Su, Yun; Huter, Eva; Ge, Yingzi; Hohenfellner, Markus; Beckhove, Philipp

    2012-04-01

    Immunotherapy is a promising approach in an effort to control castration resistant prostate cancer. We characterized tumor antigen reactive T cells in patients with prostate cancer and analyzed the suppression of antitumor responses by regulatory T cells. Peripheral blood samples were collected from 57 patients with histologically confirmed prostate cancer, 8 patients with benign prostatic hyperplasia and 16 healthy donors. Peripheral blood mononuclear cells were isolated and antigen specific interferon-γ secretion of isolated T cells was analyzed by enzyme-linked immunospot assay. T cells were functionally characterized and T-cell responses before and after regulatory T-cell depletion were compared. As test tumor antigens, a panel of 11 long synthetic peptides derived from a total of 8 tumor antigens was used, including prostate specific antigen and prostatic acid phosphatase. In patients with prostate cancer we noted a 74.5% effector T-cell response rate compared with only 25% in patients with benign prostatic hyperplasia and 31% in healthy donors. In most patients 2 or 3 tumor antigens were recognized. Comparing various disease stages there was a clear increase in the immune response against prostate specific antigens from intermediate to high risk tumors and castration resistant disease. Regulatory T-cell depletion led to a significant boost in effector T-cell responses against prostate specific antigen and prostatic acid phosphatase. Tumor specific effector T cells were detected in most patients with prostate cancer, especially those with castration resistant prostate cancer. Since effector T-cell responses against prostate specific antigens strongly increased after regulatory T-cell depletion, our results indicate that immunotherapy efficacy could be enhanced by decreasing regulatory T cells. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  11. CD4 down regulation and raft dissociation by the non-depleting YTS177 antibody hinder murine T helper cell activities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu, Cheng-Jang; Division of Biological Sciences, University of California, San Diego, La Jolla, CA, 92093; Lu, Chun-Hao

    Non-depleting YTS177 anti-CD4 monoclonal antibody (MoAb) has been reported to lead to antigen-specific immunotolerance in allograft transplantation and autoimmune diabetes, as well as possibly to inhibition of allergic inflammation in mice. However, the molecular mechanisms underlying hyporesponsive T cell responses induced by YTS177 MoAb remain elusive. Herein, we demonstrate that the YTS177 MoAb increases the levels of anergy factors p27{sup kip1} and Cbl-b, inhibits IL-2 production, and impairs calcium mobilization in activated T cells in vitro. YTS177 MoAb suppresses OVA-driven proliferation of DO11.10 CD4{sup +} T cells in vivo as well. Mechanistically, YTS177 MoAb induces tolerance by causing CD4 down-regulation through clathrin-dependentmore » and raft dissociation. The results obtained in this study lead us to propose novel protective or curative approaches to CD4 T cell-mediated diseases.« less

  12. Limited CD4+ T cell proliferation leads to preservation of CD4+ T cell counts in SIV-infected sooty mangabeys

    PubMed Central

    Chan, Ming Liang; Petravic, Janka; Ortiz, Alexandra M.; Engram, Jessica; Paiardini, Mirko; Cromer, Deborah; Silvestri, Guido; Davenport, Miles P.

    2010-01-01

    Human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) infections result in chronic virus replication and progressive depletion of CD4+ T cells, leading to immunodeficiency and death. In contrast, ‘natural hosts’ of SIV experience persistent infection with high virus replication but no severe CD4+ T cell depletion, and remain AIDS-free. One important difference between pathogenic and non-pathogenic infections is the level of activation and proliferation of CD4+ T cells. We analysed the relationship between CD4+ T cell number and proliferation in HIV, pathogenic SIV in macaques, and non-pathogenic SIV in sooty mangabeys (SMs) and mandrills. We found that CD4+ T cell proliferation was negatively correlated with CD4+ T cell number, suggesting that animals respond to the loss of CD4+ T cells by increasing the proliferation of remaining cells. However, the level of proliferation seen in pathogenic infections (SIV in rhesus macaques and HIV) was much greater than in non-pathogenic infections (SMs and mandrills). We then used a modelling approach to understand how the host proliferative response to CD4+ T cell depletion may impact the outcome of infection. This modelling demonstrates that the rapid proliferation of CD4+ T cells in humans and macaques associated with low CD4+ T cell levels can act to ‘fuel the fire’ of infection by providing more proliferating cells for infection. Natural host species, on the other hand, have limited proliferation of CD4+ T cells at low CD4+ T cell levels, which allows them to restrict the number of proliferating cells susceptible to infection. PMID:20591864

  13. Haploidentical Transplantation Without In Vitro T-Cell Depletion Results in Outcomes Equivalent to Those of Contemporaneous Matched Sibling and Unrelated Donor Transplantation for Acute Leukemia.

    PubMed

    Yu, Sijian; Fan, Qian; Sun, Jing; Fan, Zhiping; Zhang, Yu; Jiang, Qianli; Huang, Fen; Xuan, Li; Dai, Min; Zhou, Hongsheng; Liu, Hui; Liu, Qi-Fa

    2016-03-01

    The aim of the study is to determine whether HLA-haploidentical-related donor (HRD) transplant can achieve equivalent outcomes and have stronger GVL compared to HLA-matched sibling donor (MSD) and HLA-matched unrelated donor (MUD) transplants. A total of 355 consecutive patients with acute leukemia undergoing allogeneic transplant at our single institute between March 2008 and March 2014 were enrolled in this retrospective investigation. Of the 355 patients, 96 cases received HRD, 153 MSD, and 106 MUD transplants. HRD transplant was associated with higher incidences of grade II to IV aGVHD (40.6%) compared with MSD (23.5%, P = 0.002) and MUD transplants (34.0%, P = 0.049), whereas incidences of grade III to IV aGVHD (11.4%, 7.8%, 10.5%, respectively; P = 0.590) and cGVHD (29.5%, 24.0%, 29.5%, respectively; P = 0.538) did not differ among 3 groups. Five-year relapse rates were 19.2%, 26.8%, and 23.0% in 3 groups, respectively (P = 0.419). However, of 206 high-risk patients, the relapse rate in HRD transplant was lower than in MSD transplant (23.8% vs 41.9%, P = 0.026). Multivariate analysis showed that HRD had beneficial impact on relapse (for MSD: P = 0.006). Five-year transplant-related mortality was lower in MSD transplant compared with those in HRD (17.3% vs 26.4%, P = 0.041) and MUD transplants (17.3% vs 24.1%, P = 0.037). Five-year overall survival were 60.4%, 64.6%, and 61.0%, respectively, in HRD, MSD, and MUD groups (P = 0.371); 5-year disease-free survival were 59.6%, 58.8%, and 54.9%, respectively (P = 0.423). Our results suggest that HRD transplant results in outcomes equivalent to MSD and MUD transplants. HRD might carry a superior GVL effect compared to MSD for high-risk patients.

  14. Superior survival of unmanipulated haploidentical hematopoietic stem cell transplantation compared with chemotherapy alone used as post-remission therapy in adults with standard-risk acute lymphoblastic leukemia in first complete remission.

    PubMed

    Yan, Chen-Hua; Jiang, Qian; Wang, Jing; Xu, Lan-Ping; Liu, Dai-Hong; Jiang, Hao; Chen, Huan; Zhang, Xiao-Hui; Liu, Kai-Yan; Huang, Xiao-Jun

    2014-09-01

    We wanted to compare the efficacy of haploidentical hematopoietic stem cell transplantation (HSCT) with chemotherapy alone in adults with standard-risk acute lymphoblastic leukemia (ALL) in first complete remission (CR1). One hundred thirty-eight consecutive adult patients with standard-risk ALL in CR1 were retrospectively investigated. Of these patients, 59 received chemotherapy alone (group A) and 79 received unmanipulated haploidentical HSCT (group B). Cumulative incidence of relapse at 5 years in group A was significantly higher than that in group B (66.3% versus 29.9%, P < .0001). Overall and disease-free survival in group A were significantly inferior to group B (P < .0001). Moreover, multivariate analyses demonstrated that central nervous system leukemia (P = .002), T cell immunophenotype (P = .044), expression of E2A-PBX1 (P = .007), and positive minimal residual disease after the first cycle of consolidation (P = .004) were correlated with relapse. Patients with 1 of 4 risk factors were assigned to the high-risk group. Otherwise, patients without risk factors were assigned to the low-risk group. In the high-risk group, HSCT had lower relapse rates and superior DFS compared with chemotherapy (P < .05), but in the low-risk group, there were no differences between HSCT and chemotherapy (P > .05). This study is the first to demonstrate that compared with chemotherapy alone, haploidentical HSCT is a better postremission therapy in adults with standard-risk ALL in CR1. Moreover, based on the 4 risk factors, the establishment of risk stratification could identify the subgroup of patients with a higher risk of relapse in adults with standard-risk ALL in CR1. Furthermore, risk stratification-directed postremission therapies using haploidentical HSCT or chemotherapy alone not only reduce relapse rate but also avoid unnecessary treatment-related mortality and improve survival. Copyright © 2014 American Society for Blood and Marrow Transplantation. Published

  15. T cells fail to develop in the human skin-cell explants system; an inconvenient truth.

    PubMed

    Meek, Bob; Van Elssen, Catharina H M J; Huijskens, Mirelle J A J; van der Stegen, Sjoukje J C; Tonnaer, Siebe; Lumeij, Stijn B J; Vanderlocht, Joris; Kirkland, Mark A; Hesselink, Reinout; Germeraad, Wilfred T V; Bos, Gerard M J

    2011-02-18

    Haplo-identical hematopoietic stem cell (HSC) transplantation is very successful in eradicating haematological tumours, but the long post-transplant T-lymphopenic phase is responsible for high morbidity and mortality rates. Clark et al. have described a skin-explant system capable of producing host-tolerant donor-HSC derived T-cells. Because this T-cell production platform has the potential to replenish the T-cell levels following transplantation, we set out to validate the skin-explant system. Following the published procedures, while using the same commercial components, it was impossible to reproduce the skin-explant conditions required for HSC differentiation towards mature T-cells. The keratinocyte maturation procedure resulted in fragile cells with minimum expression of delta-like ligand (DLL). In most experiments the generated cells failed to adhere to carriers or were quickly outcompeted by fibroblasts. Consequently it was not possible to reproduce cell-culture conditions required for HSC differentiation into functional T-cells. Using cell-lines over-expressing DLL, we showed that the antibodies used by Clark et al. were unable to detect native DLL, but instead stained 7AAD+ cells. Therefore, it is unlikely that the observed T-lineage commitment from HSC is mediated by DLL expressed on keratinocytes. In addition, we did confirm expression of the Notch-ligand Jagged-1 by keratinocytes. Currently, and unfortunately, it remains difficult to explain the development or growth of T-cells described by Clark et al., but for the fate of patients suffering from lymphopenia it is essential to both reproduce and understand how these co-cultures really "work". Fortunately, alternative procedures to speed-up T-cell reconstitution are being established and validated and may become available for patients in the near future.

  16. B Cell Depletion Therapy Normalizes Circulating Follicular Th Cells in Primary Sjögren Syndrome.

    PubMed

    Verstappen, Gwenny M; Kroese, Frans G M; Meiners, Petra M; Corneth, Odilia B; Huitema, Minke G; Haacke, Erlin A; van der Vegt, Bert; Arends, Suzanne; Vissink, Arjan; Bootsma, Hendrika; Abdulahad, Wayel H

    2017-01-01

    To assess the effect of B cell depletion therapy on effector CD4+ T cell homeostasis and its relation to objective measures of disease activity in patients with primary Sjögren syndrome (pSS). Twenty-four patients with pSS treated with rituximab (RTX) and 24 healthy controls (HC) were included. Frequencies of circulating effector CD4+ T cell subsets were examined by flow cytometry at baseline and 16, 24, 36, and 48 weeks after the first RTX infusion. Th1, Th2, follicular Th (TFH), and Th17 cells were discerned based on surface marker expression patterns. Additionally, intracellular cytokine staining was performed for interferon-γ, interleukin (IL)-4, IL-21, and IL-17 and serum levels of these cytokines were analyzed. In patients with pSS, frequencies of circulating TFH cells and Th17 cells were increased at baseline compared with HC, whereas frequencies of Th1 and Th2 cells were unchanged. B cell depletion therapy resulted in a pronounced decrease in circulating TFH cells, whereas Th17 cells were only slightly lowered. Frequencies of IL-21-producing and IL-17-producing CD4+ T cells and serum levels of IL-21 and IL-17 were also reduced. Importantly, the decrease in circulating TFH cells was associated with lower systemic disease activity over time, as measured by the European League Against Rheumatism Sjögren's Syndrome Disease Activity Index scores and serum IgG levels. B cell depletion therapy in patients with pSS results in normalization of the elevated levels of circulating TFH cells. This reduction is associated with improved objective clinical disease activity measures. Our observations illustrate the pivotal role of the crosstalk between B cells and TFH cells in the pathogenesis of pSS.

  17. In ovo injection of anti-chicken CD25 monoclonal antibodies depletes CD4+CD25+ T cells in chickens.

    PubMed

    Shanmugasundaram, Revathi; Selvaraj, Ramesh K

    2013-01-01

    The CD4(+)CD25(+) cells have T regulatory cell properties in chickens. This study investigated the effect of in ovo injection of anti-chicken CD25 monoclonal antibodies (0.5 mg/egg) on CD4(+)CD25(+) cell depletion and on amounts of interleukin-2 mRNA and interferon-γ mRNA in CD4(+)CD25(-) cells posthatch. Anti-chicken CD25 or PBS (control) was injected into 16-d-old embryos. Chicks hatched from eggs injected with anti-chicken CD25 antibodies had a lower CD4(+)CD25(+) cell percentage in the blood until 25 d posthatch. The anti-chicken CD25 antibody injection nearly depleted CD4(+)CD25(+) cells in the blood until 16 d posthatch. At 30 d posthatch, the CD4(+)CD25(+) cell percentage in the anti-CD25-antibody-injected group was comparable with the percentage in the control group. At 16 d posthatch, the anti-chicken CD25 antibody injection decreased CD4(+)CD25(+) cell percentages in the thymus, spleen, and cecal tonsils. Chickens hatched from anti-CD25-antibody-injected eggs had approximately 25% of CD4(+)CD25(+) cells in the cecal tonsils and thymus compared with those in the cecal tonsils and thymus of the control group. The CD4(+)CD25(-) cells from the spleen and cecal tonsils of chicks hatched from anti-chicken-CD25-injected eggs had higher amounts of interferon-γ and interleukin-2 mRNA than CD4(+)CD25(-) cells from the control group. It could be concluded that injecting anti-chicken CD25 antibodies in ovo at 16 d of incubation nearly depleted the CD4(+)CD25(+) cells until 25 d posthatch.

  18. Depletion of CD11c+ Cells Does Not Influence Outcomes in Mice Subjected to Transient Middle Cerebral Artery Occlusion.

    PubMed

    Kraft, Peter; Scholtyschik, Karolina; Schuhmann, Michael K; Kleinschnitz, Christoph

    2017-01-01

    While it has been shown that different T-cell subsets have a detrimental role in the acute phase of ischemic stroke, data on the impact of dendritic cells (DC) are missing. Classic DC can be characterized by the cluster of differentiation (CD)11c surface antigen. In this study, we depleted CD11c+ cells by using a CD11c-diphtheria toxin (DTX) receptor mouse strain that allows selective depletion of CD11c+ cells by DTX injection. For stroke induction, we used the model of transient middle cerebral artery occlusion (tMCAO) and analyzed stroke volume and functional outcome on days 1 and 3 as well as expression of prototypical pro- and anti-inflammatory cytokines on day 1 after tMCAO. Three different protocols for CD11c+ cell depletion, tMCAO duration, and readout time point were applied. Injection of DTX (5 or 100 ng/g) reliably depleted CD11c+ cells without influencing the fractions of other immune cell subsets. CD11c+ cell depletion had no impact on stroke volume, but mice with a longer DTX pretreatment performed worse than those with vehicle treatment. CD11c+ cell depletion led to a decrease in cortical interleukin (IL)-1β and IL-6 messenger ribonucleic acid levels. We show, for the first time, that CD11c+ cell depletion does not influence stroke volume in a mouse model of focal cerebral ischemia. Nevertheless, given the unspecificity of the CD11c surface antigen for DC, mouse models that allow a more selective depletion of DC are needed to investigate the role of DC in stroke pathophysiology. © 2017 S. Karger AG, Basel.

  19. Tolerance induction between two different strains of parental mice prevents graft-versus-host disease in haploidentical hematopoietic stem cell transplantation to F1 mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guo, Yixian; Zhang, Lanfang; Wan, Suigui

    Highlights: • Injection of UVB-irradiated iDCs induces alloantigen tolerance. • This alloantigen tolerance may be associated regulatory T cell induction. • Tolerant mice serve as bone marrow donors reduces GVHD to their F1 recipients in allo-HSCT. • Tolerance is maintained in F1 recipients for long time post HSCT. - Abstract: Haploidentical hematopoietic stem cell transplantation (Haplo-HSCT) has been employed worldwide in recent years and led to favorable outcome in a group of patients who do not have human leukocyte antigen (HLA)-matched donors. However, the high incidence of severe graft-versus-host disease (GVHD) is a major problem for Haplo-HSCT. In the currentmore » study, we performed a proof of concept mouse study to test whether induction of allogeneic tolerance between two different parental strains was able to attenuate GVHD in Haplo-HSCT to the F1 mice. We induced alloantigen tolerance in C3H mice (H-2k) using ultraviolet B (UVB) irradiated immature dendritic cells (iDCs) derived from the cultures of Balb/c bone marrow cells. Then, we performed Haplo-HSCT using tolerant C3H mice as donors to F1 mice (C3H × Balb/c). The results demonstrated that this approach markedly reduced GVHD-associated death and significantly prolonged the survival of recipient mice in contrast to the groups with donors (C3H mice) that received infusion of non-UVB-irradiated DCs. Further studies showed that there were enhanced Tregs in the tolerant mice and alloantigen-specific T cell response was skewed to more IL-10-producing T cells, suggesting that these regulatory T cells might have contributed to the attenuation of GVHD. This study suggests that it is a feasible approach to preventing GVHD in Haplo-HSCT in children by pre-induction of alloantigen tolerance between the two parents. This concept may also lead to more opportunities in cell-based immunotherapy for GVHD post Haplo-HSCT.« less

  20. Tumor-promoting desmoplasia is disrupted by depleting FAP-expressing stromal cells

    PubMed Central

    Scholler, John; Monslow, James; Avery, Diana; Newick, Kheng; O'Brien, Shaun; Evans, Rebecca A.; Bajor, David J.; Clendenin, Cynthia; Durham, Amy C; Buza, Elizabeth L; Vonderheide, Robert H; June, Carl H

    2015-01-01

    Malignant cells drive the generation of a desmoplastic and immunosuppressive tumor microenvironment. Cancer-associated stromal cells (CASCs) are a heterogeneous population that provides both negative and positive signals for tumor cell growth and metastasis. Fibroblast activation protein (FAP) is a marker of a major subset of CASCs in virtually all carcinomas. Clinically, FAP expression serves as an independent negative prognostic factor for multiple types of human malignancies. Prior studies established that depletion of FAP+ cells inhibits tumor growth by augmenting anti-tumor immunity. However, the potential for immune-independent effects on tumor growth have not been defined. Herein, we demonstrate that FAP+ CASCs are required for maintenance of the provisional tumor stroma since depletion of these cells, by adoptive transfer of FAP-targeted chimeric antigen receptor (CAR) T cells, reduced extracellular matrix proteins and glycosaminoglycans. Adoptive transfer of FAP-CAR T cells also decreased tumor vascular density and restrained growth of desmoplastic human lung cancer xenografts and syngeneic murine pancreatic cancers in an immune-independent fashion. Adoptive transfer of FAP-CAR T cells also restrained autochthonous pancreatic cancer growth. These data distinguish the function of FAP+ CASCs from other CASC subsets and provide support for further development of FAP+ stromal cell-targeted therapies for the treatment of solid tumors. PMID:25979873

  1. Tumor-Promoting Desmoplasia Is Disrupted by Depleting FAP-Expressing Stromal Cells.

    PubMed

    Lo, Albert; Wang, Liang-Chuan S; Scholler, John; Monslow, James; Avery, Diana; Newick, Kheng; O'Brien, Shaun; Evans, Rebecca A; Bajor, David J; Clendenin, Cynthia; Durham, Amy C; Buza, Elizabeth L; Vonderheide, Robert H; June, Carl H; Albelda, Steven M; Puré, Ellen

    2015-07-15

    Malignant cells drive the generation of a desmoplastic and immunosuppressive tumor microenvironment. Cancer-associated stromal cells (CASC) are a heterogeneous population that provides both negative and positive signals for tumor cell growth and metastasis. Fibroblast activation protein (FAP) is a marker of a major subset of CASCs in virtually all carcinomas. Clinically, FAP expression serves as an independent negative prognostic factor for multiple types of human malignancies. Prior studies established that depletion of FAP(+) cells inhibits tumor growth by augmenting antitumor immunity. However, the potential for immune-independent effects on tumor growth have not been defined. Herein, we demonstrate that FAP(+) CASCs are required for maintenance of the provisional tumor stroma because depletion of these cells, by adoptive transfer of FAP-targeted chimeric antigen receptor (CAR) T cells, reduced extracellular matrix proteins and glycosaminoglycans. Adoptive transfer of FAP-CAR T cells also decreased tumor vascular density and restrained growth of desmoplastic human lung cancer xenografts and syngeneic murine pancreatic cancers in an immune-independent fashion. Adoptive transfer of FAP-CAR T cells also restrained autochthonous pancreatic cancer growth. These data distinguish the function of FAP(+) CASCs from other CASC subsets and provide support for further development of FAP(+) stromal cell-targeted therapies for the treatment of solid tumors. ©2015 American Association for Cancer Research.

  2. Comparable survival using a CMV-matched or a mismatched donor for CMV+ patients undergoing T-replete haplo-HSCT with PT-Cy for acute leukemia: a study of behalf of the infectious diseases and acute leukemia working parties of the EBMT.

    PubMed

    Cesaro, Simone; Crocchiolo, Roberto; Tridello, Gloria; Knelange, Nina; Van Lint, Maria Teresa; Koc, Yener; Ciceri, Fabio; Gülbas, Zafer; Tischer, Johanna; Afanasyev, Boris; Bruno, Benedetto; Castagna, Luca; Blaise, Didier; Mohty, Mohamad; Irrera, Giuseppe; Diez-Martin, J L; Pierelli, Luca; Pioltelli, Pietro; Arat, Mutlu; Delia, Mario; Fagioli, Franca; Ehninger, Gerhard; Aljurf, Mahmoud; Carella, Angelo Michele; Ozdogu, Hakan; Mikulska, Malgorzata; Ljungman, Per; Nagler, Arnon; Styczynski, Jan

    2018-04-01

    The role of donor CMV serostatus in the setting of non T-cell depleted haplo-HSCT with post-transplant cyclophosphamide (PT-Cy) has not been specifically addressed so far. Here we analyzed the impact of the donor CMV serological status on the outcome of 983 CMV seropositive (CMV+), acute leukemia patients receiving a first, non T-cell depleted haplo-HSCT registered in the EBMT database. The 1-year NRM was 21.3% (95% CI: 18.4-24.8) and 18.8% (95% CI: 13.8-25.5) in the CMV D+/R+ and D-/R+ pairs, respectively (p = 0.40). Similarly, 1-year OS was 55.1% (95% CI: 50.1-58.0) and 55.7% (95% CI: 48.0-62.8) in the same groups (p = 0.50). The other main outcomes were comparable. No difference in NRM nor OS was observed after stratification for the intensity of conditioning and multivariate anaysis confirmed the lack of significant association with NRM or OS. In conclusion, the choice of a CMV-seronegative donor did not impair early survival of CMV-seropositive patients with acute leukemia after a first, non T-cell depleted haploidentical HSCT and PT-Cy among this series of 983 consecutive patients. Future research may focus on the assessment of the hierarchy of all the donor variables.

  3. Haploidentical hematopoietic stem cell transplantation for paediatric high-risk T-cell acute lymphoblastic leukaemia.

    PubMed

    Xu, Zheng-Li; Huang, Xiao-Jun; Liu, Kai-Yan; Chen, Huan; Zhang, Xiao-Hui; Han, Wei; Chen, Yu-Hong; Wang, Feng-Rong; Wang, Jing-Zhi; Wang, Yu; Chen, Yao; Yan, Chen-Hua; Xu, Lan-Ping

    2016-06-01

    Paediatric HR T-cell ALL demonstrates dismal prognosis with chemotherapy, and poor outcomes could be improved with allo-SCT. HID-SCT is an almost immediately available choice; however, few studies have focused on the outcomes of HID-SCT for paediatric HR T-ALL. Forty-eight consecutive HR T-ALL children who underwent HID-SCT were included. Survival outcomes and factors predictive of outcomes were retrospectively analysed. Of the 48 patients, 35 were in CR1, 10 in CR2, and three in relapse. The cumulative incidence of grade 3/4 aGVHD was 10.4% and that of extensive cGVHD was 28.4%. The CIR at three yr was 30.8% and that of NRM at three yr was 14.7%. At a median follow-up of 20.0 (range 2.5-124.2) months, the three-yr LFS was 54.4%. Children who received transplants during CR1 had a better LFS (65.7% vs. 26.0%, p = 0.008) and a lower relapse rate (19.8% vs. 56.7%, p = 0.014) compared to those during non-CR1. HID-SCT is feasible for HR T-ALL children, and survival outcomes are better when performed in CR1 compared to non-CR1. Prospective clinical trials would be needed to confirm that. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Korean Red Ginseng Slows Depletion of CD4 T Cells in Human Immunodeficiency Virus Type 1-Infected Patients

    PubMed Central

    Sung, Heungsup; Kang, Sang-Moo; Lee, Moo-Song; Kim, Tai Gyu; Cho, Young-Keol

    2005-01-01

    We have previously showed that long-term intake of Korean red ginseng (KRG) delayed disease progression in human immunodeficiency virus type 1 (HIV-1)-infected patients. In the present study, to investigate whether this slow progression was affected by KRG intake alone or in combination with HLA factor, we analyzed clinical data in 68 HIV-1-infected patients who lived for more than 5 years without antiretroviral therapy. The average KRG intake over 111.9 ± 31.3 months was 4,082 ± 3,928 g, and annual decrease in CD4 T cells was 35.0 ± 28.7/μl. Data analysis showed that there are significant inverse correlations between the HLA prognostic score (0.29 ± 1.19) and annual decrease in CD4 T cells (r = −0.347; P < 0.01) as well as between the amount of KRG intake and annual decrease in CD4 T cells (r = −0.379; P < 0.01). In addition, KRG intake significantly slowed the decrease in CD4 T cells even when influence of HLA class I was statistically eliminated (repeated-measure analysis of variance; P < 0.05). We also observed significant correlation between KRG intake and a decrease in serum-soluble CD8 antigen level (r = 0.62; P < 0.001). In conclusion, these data show that KRG intake independently and significantly affected the slow depletion of CD4 T cells irrespective of HLA class I. PMID:15817756

  5. Haploidentical bone marrow transplantation with post transplant cyclophosphamide for patients with X-linked adrenoleukodystrophy: a suitable choice in an urgent situation.

    PubMed

    Fernandes, Juliana Folloni; Bonfim, Carmem; Kerbauy, Fábio Rodrigues; Rodrigues, Morgani; Esteves, Iracema; Silva, Nathalia Halley; Azambuja, Alessandra Prandini; Mantovani, Luiz Fernando; Kutner, José Mauro; Loth, Gisele; Kuwahara, Cilmara Cristina; Bueno, Clarissa; Kondo, Andrea Tiemi; Ribeiro, Andreza Alice Feitosa; Kok, Fernando; Hamerschlak, Nelson

    2018-04-01

    Allogeneic hematopoietic stem cell transplantation (HSCT) is the only treatment that enhances survival and stabilizes neurologic symptoms in X-linked adrenoleukodystrophy (X-ALD) with cerebral involvement, a severe demyelinating disease of childhood. Patients with X-ALD who lack a well-matched HLA donor need a rapid alternative. Haploidentical HSCT using post transplant cyclophosphamide (PT/Cy) has been performed in patients with malignant and nonmalignant diseases showing similar outcomes compared to other alternative sources. We describe the outcomes of transplants performed for nine X-ALD patients using haploidentical donors and PT/Cy. Patients received conditioning regimen with fludarabine 150 mg/m 2 , cyclophosphamide 29 mg/kg and 2 Gy total body irradiation (TBI) with or without antithymocyte globulin. Graft-vs.-host disease prophylaxis consisted of cyclophosphamide 50 mg/kg/day on days +3 and +4, tacrolimus or cyclosporine A and mycophenolate mofetil. One patient had a primary graft failure and was not eligible for a second transplant. Three patients had secondary graft failure and were successfully rescued with second haploidentical transplants. Trying to improve engraftment, conditioning regimen was changed, substituting 2 Gy TBI for 4 Gy total lymphoid irradiation. Eight patients are alive and engrafted (17-37 months after transplant). Haploidentical HSCT with PT/Cy is a feasible alternative for X-ALD patients lacking a suitable matched donor. Graft failure has to be addressed in further studies.

  6. Early Improvement in Marrow Fibrosis Following Haploidentical Stem Cell Transplantation for a Patient with Myelodysplastic Syndrome with Bone Marrow Fibrosis

    PubMed Central

    Takahashi, Shuichiro; Tsumanuma, Riko; Aizawa, Keiko; Osakabe, Mitsumasa; Maeda, Kunihiko; Omoto, Ejiro

    2016-01-01

    The prognosis for myelodysplastic syndrome with bone marrow fibrosis (MDS-F) is worse than the prognosis of MDS without fibrosis. Hematopoietic stem cell transplantation (HSCT) is the only curative therapy; however, the indications and the procedures involved in HSCT remain unclear. We herein describe a 69-year-old Japanese man with MDS-F who received haploidentical HSCT and post-transplantation cyclophosphamide. Although the first HSCT resulted in secondary graft failure, the second HSCT using PTCy led to successful engraftment after early improvement in fibrosis. Since the incidence of graft failure is high in myelofibrosis patients, a secondary HSCT using PTCy may be successful if employed. PMID:27853082

  7. Improving the Safety of T Cell Therapies using an Inducible Caspase-9 Gene

    PubMed Central

    Zhou, Xiaoou; Brenner, Malcolm K.

    2016-01-01

    Adoptive transfer of T cells can be an effective anti-cancer treatment. However, uncontrolled or unpredictable immediate or persistent toxicities are a source of concern. The ability to conditionally eliminate aberrant cells in vivo therefore is becoming a critical step for the successful translation of this approach to the clinic. We review the evolution of safety systems, focusing on a suicide switch that can be expressed stably and efficiently in human T cells without impairing phenotype, function or antigen specificity. This system is based on the fusion of human caspase 9 to a modified human FK-binding protein, allowing conditional dimerization in the presence of an otherwise bioinert small molecule drug. When exposed to the synthetic dimerizing drug, the inducible caspase 9 (iC9) becomes activated and leads to the rapid apoptosis of cells expressing this construct. We have demonstrated the clinical feasibility and efficacy of this approach after haploidentical hematopoietic stem cell transplant (haplo-HSCT). Here we review the benefits and limitations of the approach. PMID:27473568

  8. Intra-Hepatic Depletion of Mucosal-Associated Invariant T Cells in Hepatitis C Virus-Induced Liver Inflammation.

    PubMed

    Bolte, Fabian J; O'Keefe, Ashley C; Webb, Lauren M; Serti, Elisavet; Rivera, Elenita; Liang, T Jake; Ghany, Marc; Rehermann, Barbara

    2017-11-01

    controls. Anti-viral therapy rapidly decreased liver inflammation and MAIT cell activation and cytotoxicity, and increased the MAIT cell frequency among intra-hepatic but not blood T cells. The MAIT cell response to T-cell receptor-mediated stimulation did not change during the 12 weeks of antiviral therapy. In analyses of paired blood and liver samples from patients with chronic HCV infection before, during, and after antiviral therapy with sofosbuvir and velpatasvir, we found that intrahepatic MAIT cells are activated by monocyte-derived cytokines and depleted in HCV-induced liver inflammation. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

  9. B-cell depletion and remissions of malignancy along with cytokine-associated toxicity in a clinical trial of anti-CD19 chimeric-antigen-receptor–transduced T cells

    PubMed Central

    Dudley, Mark E.; Feldman, Steven A.; Wilson, Wyndham H.; Spaner, David E.; Maric, Irina; Stetler-Stevenson, Maryalice; Phan, Giao Q.; Hughes, Marybeth S.; Sherry, Richard M.; Yang, James C.; Kammula, Udai S.; Devillier, Laura; Carpenter, Robert; Nathan, Debbie-Ann N.; Morgan, Richard A.; Laurencot, Carolyn; Rosenberg, Steven A.

    2012-01-01

    We conducted a clinical trial to assess adoptive transfer of T cells genetically modified to express an anti-CD19 chimeric Ag receptor (CAR). Our clinical protocol consisted of chemotherapy followed by an infusion of anti–CD19-CAR–transduced T cells and a course of IL-2. Six of the 8 patients treated on our protocol obtained remissions of their advanced, progressive B-cell malignancies. Four of the 8 patients treated on the protocol had long-term depletion of normal polyclonal CD19+ B-lineage cells. Cells containing the anti-CD19 CAR gene were detected in the blood of all patients. Four of the 8 treated patients had prominent elevations in serum levels of the inflammatory cytokines IFNγ and TNF. The severity of acute toxicities experienced by the patients correlated with serum IFNγ and TNF levels. The infused anti–CD19-CAR–transduced T cells were a possible source of these inflammatory cytokines because we demonstrated peripheral blood T cells that produced TNF and IFNγ ex vivo in a CD19-specific manner after anti–CD19-CAR–transduced T-cell infusions. Anti–CD19-CAR–transduced T cells have great promise to improve the treatment of B-cell malignancies because of a potent ability to eradicate CD19+ cells in vivo; however, reversible cytokine-associated toxicities occurred after CAR–transduced T-cell infusions. This trial was registered with ClinicalTrials.gov as NCT00924326. PMID:22160384

  10. Cladribine treatment of multiple sclerosis is associated with depletion of memory B cells.

    PubMed

    Ceronie, Bryan; Jacobs, Benjamin M; Baker, David; Dubuisson, Nicolas; Mao, Zhifeng; Ammoscato, Francesca; Lock, Helen; Longhurst, Hilary J; Giovannoni, Gavin; Schmierer, Klaus

    2018-05-01

    The mechanism of action of oral cladribine, recently licensed for relapsing multiple sclerosis, is unknown. To determine whether cladribine depletes memory B cells consistent with our recent hypothesis that effective, disease-modifying treatments act by physical/functional depletion of memory B cells. A cross-sectional study examined 40 people with multiple sclerosis at the end of the first cycle of alemtuzumab or injectable cladribine. The relative proportions and absolute numbers of peripheral blood B lymphocyte subsets were measured using flow cytometry. Cell-subtype expression of genes involved in cladribine metabolism was examined from data in public repositories. Cladribine markedly depleted class-switched and unswitched memory B cells to levels comparable with alemtuzumab, but without the associated initial lymphopenia. CD3 + T cell depletion was modest. The mRNA expression of metabolism genes varied between lymphocyte subsets. A high ratio of deoxycytidine kinase to group I cytosolic 5' nucleotidase expression was present in B cells and was particularly high in mature, memory and notably germinal centre B cells, but not plasma cells. Selective B cell cytotoxicity coupled with slow repopulation kinetics results in long-term, memory B cell depletion by cladribine. These may offer a new target, possibly with potential biomarker activity, for future drug development.

  11. Depletion of pro-inflammatory CD161(+) double negative (CD3(+)CD4(-)CD8(-)) T cells in AIDS patients is ameliorated by expansion of the γδ T cell population.

    PubMed

    Singleterry, Will L; Henderson, Harold; Cruse, Julius M

    2012-02-01

    In this present investigation, flow cytometry was utilized to evaluate 13 healthy controls and 31 HIV-1 infected patients who had advanced to the AIDS stage of infection (CD4 count below 200 cells/mm(3)), for the expression of CD161 on CD3(+) double negative (DN) (CD3(+)CD4(-)CD8(-)) T cells, CD4(+) T cells, CD8(+) T cells and γδ T cells. The observed depletion of CD161(+) T cells from peripheral circulation was due primarily to the loss of CD4(+)CD161(+) T cells; as these cells represented 8.67±0.74% of the total healthy control peripheral T cell population, while the CD4(+)CD161(+) T cells of the AIDS group represented only 3.35±0.41% (p=<0.0001) of the total peripheral T cell population. We have also shown here that the DN T cell population was more than doubled in the AIDS group, with the DN T cell population expanding from 3.29±0.45% of the healthy control peripheral T cell population to 8.64±1.16% (p=0.0001) of the AIDS group peripheral T cell population. By evaluating the expression of CD161 on the surface of the DN T cells we showed that within the healthy control group, 47.4±4.99% of the DN T cells were positive for the expression of CD161, while only 26.4±3.54% (p=0.002) of the AIDS group's DN T cells expressed CD161. Despite CD161 expression being halved on the DN T cells of the AIDS group, when we compared the total peripheral T cell percentage of CD161(+) DN T cells between the healthy control group and the AIDS group, there was no statistical difference. Even though only 26.4% DN T cells within the AIDS group were positive for CD161(+), the overall DN T cell population had expanded to such an extent that there was no statistical difference between the groups with regard to CD161(+) DN T cells as a percentage of the total peripheral T cell population. Furthermore, we showed that within the DN T cell population, there was an approximate 2:1 ratio of γδ to αβ T cells, and this ratio was maintained in both the healthy control group and the

  12. Unmanipulated haploidentical haematopoietic stem cell transplantation for children with severe aplastic anaemia.

    PubMed

    Zhu, Hua; Luo, Rong Mu; Luan, Zuo; Lee, Vincent; Zhu, Yi Ping; Luo, Cheng Juan; Tang, Xiang Feng; Si, Ying Jian; Chen, Jing

    2016-09-01

    Haploidentical haematopoietic stem cell transplantation (haplo-HSCT) used to be a third-line treatment option for childhood severe aplastic anaemia (SAA). We conducted this retrospective study of 36 children (38 transplants) who received haplo-HSCT from human leucocyte antigen (HLA)-mismatched related donors between July 2002 and November 2013 at five HSCT centres in China, including 17 cases that were 5/6 HLA matched (Group 1) and 21 that were 4/6 or 3/6 HLA matched (Group 2). Although patients in Group 2 had a higher incidence of grade II-IV acute graft-versus-host disease (57·9% vs. 5·9%, P = 0·001), they had similar rates of graft failure (5·3% vs. 5·9%, P = 0·742) and overall survival (80·8% vs. 93·8%, P = 0·234) as Group 1. Unmanipulated haplo-HSCT is an effective treatment for SAA children with satisfactory outcome of this cohort, especially in the 5/6 HLA-matched group. For patients in critical situations, such as unresponsive to immunosuppressive therapy, refractory infection and failing first HSCT, to bring forward the timing of haplo-HSCT is a feasible salvage strategy with better and faster donor accessibility. © 2016 John Wiley & Sons Ltd.

  13. Spatially selective depleting tumor-associated negative regulatory T-(Treg) cells with near infrared photoimmunotherapy (NIR-PIT): A new cancer immunotherapy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Kobayashi, Hisataka

    2017-02-01

    Near infrared photoimmunotherapy (NIR-PIT) is a new type of molecularly-targeted photo-therapy based on conjugating a near infrared silica-phthalocyanine dye, IR700, to a monoclonal antibody (MAb) targeting target-specific cell-surface molecules. When exposed to NIR light, the conjugate rapidly induces a highly-selective cell death only in receptor-positive, MAb-IR700-bound cells. Current immunotherapies for cancer seek to modulate the balance among different immune cell populations, thereby promoting anti-tumor immune responses. However, because these are systemic therapies, they often cause treatment-limiting autoimmune adverse effects. It would be ideal to manipulate the balance between suppressor and effector cells within the tumor without disturbing homeostasis elsewhere in the body. CD4+CD25+Foxp3+ regulatory T cells (Tregs) are well-known immune-suppressor cells that play a key role in tumor immuno-evasion and have been the target of systemic immunotherapies. We used CD25-targeted NIR-PIT to selectively deplete Tregs, thus activating CD8+ T and NK cells and restoring local anti-tumor immunity. This not only resulted in regression of the treated tumor but also induced responses in separate untreated tumors of the same cell-line derivation. We conclude that CD25-targeted NIR-PIT causes spatially selective depletion of Tregs, thereby providing an alternative approach to cancer immunotherapy that can treat not only local tumors but also distant metastatic tumors.

  14. Experimentally-induced immune activation in natural hosts of SIV induces significant increases in viral replication and CD4+ T cell depletion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ribeiro, Ruy M

    2008-01-01

    Chronically SIVagm-infected African green monkeys (AGMs) have a remarkably stable non-pathogenic disease course, with levels of immune activation in chronic SIVagm infection similar to those observed in uninfected monkeys and stable viral loads (VLs) for long periods of time. In vivo administration of lipopolysaccharide (LPS) or an IL-2/diphtheria toxin fusion protein (Ontak) to chronically SIVagm-infected AGMs triggered increases in immune activation and subsequently of viral replication and depletion of intestinal CD4{sup +} T cells. Our study indicates that circulating microbial products can increase viral replication by inducing immune activation and increasing the number of viral target cells, thus demonstrating thatmore » immune activation and T cell prolifeation are key factors in AIDS pathogenesis.« less

  15. Inhibition of phosphoantigen-mediated gammadelta T-cell proliferation by CD4+ CD25+ FoxP3+ regulatory T cells.

    PubMed

    Kunzmann, Volker; Kimmel, Brigitte; Herrmann, Thomas; Einsele, Hermann; Wilhelm, Martin

    2009-02-01

    Tumour growth promotes the expansion of CD4(+) CD25(+) FoxP3(+) regulatory T cells (Tregs) which suppress various arms of immune responses and might therefore contribute to tumour immunosurveillance. In this study, we found an inverse correlation between circulating Treg frequencies and phosphoantigen-induced gammadelta T-cell proliferation in cancer patients, which prompted us to address the role of Tregs in controlling the gammadelta T-cell arm of innate immune responses. In vitro, human Treg-peripheral blood mononuclear cell (PBMC) co-cultures strongly inhibited phosphoantigen-induced proliferation of gammadelta T cells and depletion of Tregs restored the impaired phosphoantigen-induced gammadelta T-cell proliferation of cancer patients. Tregs did not suppress other effector functions of gammadelta T cells such as cytokine production or cytotoxicity. Our experiments indicate that Tregs do not mediate their suppressive activity via a cell-cell contact-dependent mechanism, but rather secrete a soluble non-proteinaceous factor, which is independent of known soluble factors interacting with amino acid depletion (e.g. arginase-diminished arginine and indolamine 2,3-dioxygenase-diminished tryptophan) or nitric oxide (NO) production. However, the proliferative activity of alphabeta T cells was not affected by this cell-cell contact-independent suppressive activity induced by Tregs. In conclusion, these findings indicate a potential new mechanism by which Tregs can specifically suppress gammadelta T cells and highlight the strategy of combining Treg inhibition with subsequent gammadelta T-cell activation to enhance gammadelta T cell-mediated immunotherapy.

  16. Haploidentical hematopoietic stem cell transplant with umbilical cord-derived multipotent mesenchymal cell infusion for the treatment of high-risk acute leukemia in children.

    PubMed

    Zhu, Ling; Wang, Zhidong; Zheng, Xiaoli; Ding, Li; Han, Dongmei; Yan, Hongmin; Guo, Zikuan; Wang, Hengxiang

    2015-05-01

    In this study, 25 children with high-risk acute leukemia received haploidentical hematopoietic stem cell transplant (haplo-HSCT) with co-transfusion of umbilical cord multipotent mesenchymal cells (UC-MSCs). Adverse effects, hematopoietic recovery, complications and outcome were observed during a median follow-up of 12.8 months (range: 3-25 months). Myeloid engraftment was rapid, and the median time to neutrophil and platelet recovery was 15.12 days and 20.08 days, respectively. Eight patients developed grade I skin acute graft-versus-host disease (aGVHD) that responded well to standard steroid therapy. Of note, cytomegalovirus viremia was observed in most patients (23/25 cases). Patients died mainly of leukemia relapse and pulmonary complication. Fourteen patients are currently alive and remain with full donor chimerism at the time of reporting. The present results suggest further clinical trials to testify the effectiveness of UC-MSCs to prevent aGVHD in haplo-HSCT for treating children with high-risk leukemia.

  17. Modulation of Haemonchus contortus infection by depletion of γδ+ T cells in parasite resistant Canaria Hair Breed sheep.

    PubMed

    Hernández, Julia N; Meeusen, Els; Stear, Michael; Rodríguez, Francisco; Piedrafita, David; González, Jorge F

    2017-04-15

    Canaria Hair Breed (CHB) sheep display resistance against the adult stage of the nematode, Haemonchus contortus. Previous studies have suggested significant correlations between γδ + T lymphocytes and fecundity of female adult worms, suggesting a novel role in immune modulation by these cells. The largest proportion of γδ + T lymphocytes in sheep are the subpopulation of γδ + /WC1 + T cells. The aim of this study was to evaluate the effect of γδ + ⁄WC1 + T cell depletion via infusion of anti-γδ/WC1 monoclonal antibody (mAb) on the subsequent immune response of CHB sheep infected with H. contortus. Significantly lower γδ + T cell levels in both peripheral blood and in the basal layers of the abomasal tissue resulted following anti-γδ/WC1 mAb infusion of CHB sheep compared to control animals. Worms recovered from the anti-γδ/WC1 mAb treated CHB sheep had significantly longer female worms with correspondingly more eggs in utero than the saline control group. Significant correlations between eosinophils and worm length and fecundity were no longer apparent in the anti-γδ/WC1 mAb treated CHB sheep. These results support the notion that γδ + T cells in CHB sheep play a critical role in fecundity regulation (length and eggs in utero) of H. contortus adult female worms, and highlights a new mechanism of modulation by this lymphocyte population, possibly involving eosinophil activation. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Transient Treg depletion enhances therapeutic anti-cancer vaccination.

    PubMed

    Fisher, Scott A; Aston, Wayne J; Chee, Jonathan; Khong, Andrea; Cleaver, Amanda L; Solin, Jessica N; Ma, Shaokang; Lesterhuis, W Joost; Dick, Ian; Holt, Robert A; Creaney, Jenette; Boon, Louis; Robinson, Bruce; Lake, Richard A

    2017-03-01

    Regulatory T cells (Treg) play an important role in suppressing anti- immunity and their depletion has been linked to improved outcomes. To better understand the role of Treg in limiting the efficacy of anti-cancer immunity, we used a Diphtheria toxin (DTX) transgenic mouse model to specifically target and deplete Treg. Tumor bearing BALB/c FoxP3.dtr transgenic mice were subjected to different treatment protocols, with or without Treg depletion and tumor growth and survival monitored. DTX specifically depleted Treg in a transient, dose-dependent manner. Treg depletion correlated with delayed tumor growth, increased effector T cell (Teff) activation, and enhanced survival in a range of solid tumors. Tumor regression was dependent on Teffs as depletion of both CD4 and CD8 T cells completely abrogated any survival benefit. Severe morbidity following Treg depletion was only observed, when consecutive doses of DTX were given during peak CD8 T cell activation, demonstrating that Treg can be depleted on multiple occasions, but only when CD8 T cell activation has returned to base line levels. Finally, we show that even minimal Treg depletion is sufficient to significantly improve the efficacy of tumor-peptide vaccination. BALB/c.FoxP3.dtr mice are an ideal model to investigate the full therapeutic potential of Treg depletion to boost anti-tumor immunity. DTX-mediated Treg depletion is transient, dose-dependent, and leads to strong anti-tumor immunity and complete tumor regression at high doses, while enhancing the efficacy of tumor-specific vaccination at low doses. Together this data highlight the importance of Treg manipulation as a useful strategy for enhancing current and future cancer immunotherapies.

  19. Partial T-cell depletion improves the composite endpoint graft-versus-host disease-free, relapse-free survival after allogeneic hematopoietic stem cell transplantation.

    PubMed

    Simonetta, Federico; Masouridi-Levrat, Stavroula; Beauverd, Yan; Tsopra, Olga; Tirefort, Yordanka; Koutsi, Aikaterini; Stephan, Caroline; Polchlopek-Blasiak, Karolina; Pradier, Amandine; Dantin, Carole; Ansari, Marc; Roosnek, Eddy; Chalandon, Yves

    2018-03-01

    Graft-versus-host disease (GvHD)-free, relapse-free survival (GRFS) is a recently reported composite endpoint that allows to simultaneously estimate risk of death, relapse and GvHD after allogeneic hematopoietic stem cell transplantation (HSCT). In this retrospective study comprising 333 patients transplanted for hematologic malignancies, we compared GRFS in patients receiving partial T-cell-depleted (pTCD) grafts with patients receiving T-cell-replete grafts (No-TCD). pTCD was associated with a significantly improved GRFS. The beneficial effect of pTCD on GRFS remained highly significant in multivariable analysis taking into account clinical factors differing between patient groups. We observed no effect of pTCD on overall survival, progression-free survival, and relapse cumulative incidence, while non-relapse mortality cumulative incidence was significantly lower in patients receiving pTCD. The results of our retrospective analysis suggest that pTCD could improve GRFS in allogeneic HSCT recipients without significantly affecting OS and PFS, thus improving patients' quality of life without impairing the curative potential of allogeneic HSCT.

  20. A Convenient Model of Severe, High Incidence Autoimmune Gastritis Caused by Polyclonal Effector T Cells and without Perturbation of Regulatory T Cells

    PubMed Central

    Tu, Eric; Ang, Desmond K. Y.; Hogan, Thea V.; Read, Simon; Chia, Cheryl P. Z.; Gleeson, Paul A.; van Driel, Ian R.

    2011-01-01

    Autoimmune gastritis results from the breakdown of T cell tolerance to the gastric H+/K+ ATPase. The gastric H+/K+ ATPase is responsible for the acidification of gastric juice and consists of an α subunit (H/Kα) and a β subunit (H/Kβ). Here we show that CD4+ T cells from H/Kα-deficient mice (H/Kα−/−) are highly pathogenic and autoimmune gastritis can be induced in sublethally irradiated wildtype mice by adoptive transfer of unfractionated CD4+ T cells from H/Kα−/− mice. All recipient mice consistently developed the most severe form of autoimmune gastritis 8 weeks after the transfer, featuring hypertrophy of the gastric mucosa, complete depletion of the parietal and zymogenic cells, and presence of autoantibodies to H+/K+ ATPase in the serum. Furthermore, we demonstrated that the disease significantly affected stomach weight and stomach pH of recipient mice. Depletion of parietal cells in this disease model required the presence of both H/Kα and H/Kβ since transfer of H/Kα−/− CD4+ T cells did not result in depletion of parietal cells in H/Kα−/− or H/Kβ−/− recipient mice. The consistency of disease severity, the use of polyclonal T cells and a specific T cell response to the gastric autoantigen make this an ideal disease model for the study of many aspects of organ-specific autoimmunity including prevention and treatment of the disease. PMID:22096532

  1. γδ T Cells Support Pancreatic Oncogenesis by Restraining αβ T Cell Activation.

    PubMed

    Daley, Donnele; Zambirinis, Constantinos Pantelis; Seifert, Lena; Akkad, Neha; Mohan, Navyatha; Werba, Gregor; Barilla, Rocky; Torres-Hernandez, Alejandro; Hundeyin, Mautin; Mani, Vishnu Raj Kumar; Avanzi, Antonina; Tippens, Daniel; Narayanan, Rajkishen; Jang, Jung-Eun; Newman, Elliot; Pillarisetty, Venu Gopal; Dustin, Michael Loran; Bar-Sagi, Dafna; Hajdu, Cristina; Miller, George

    2016-09-08

    Inflammation is paramount in pancreatic oncogenesis. We identified a uniquely activated γδT cell population, which constituted ∼40% of tumor-infiltrating T cells in human pancreatic ductal adenocarcinoma (PDA). Recruitment and activation of γδT cells was contingent on diverse chemokine signals. Deletion, depletion, or blockade of γδT cell recruitment was protective against PDA and resulted in increased infiltration, activation, and Th1 polarization of αβT cells. Although αβT cells were dispensable to outcome in PDA, they became indispensable mediators of tumor protection upon γδT cell ablation. PDA-infiltrating γδT cells expressed high levels of exhaustion ligands and thereby negated adaptive anti-tumor immunity. Blockade of PD-L1 in γδT cells enhanced CD4(+) and CD8(+) T cell infiltration and immunogenicity and induced tumor protection suggesting that γδT cells are critical sources of immune-suppressive checkpoint ligands in PDA. We describe γδT cells as central regulators of effector T cell activation in cancer via novel cross-talk. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Effects of B Cell Depletion on Early Mycobacterium tuberculosis Infection in Cynomolgus Macaques.

    PubMed

    Phuah, Jiayao; Wong, Eileen A; Gideon, Hannah P; Maiello, Pauline; Coleman, M Teresa; Hendricks, Matthew R; Ruden, Rachel; Cirrincione, Lauren R; Chan, John; Lin, Philana Ling; Flynn, JoAnne L

    2016-05-01

    Although recent studies in mice have shown that components of B cell and humoral immunity can modulate the immune responses against Mycobacterium tuberculosis, the roles of these components in human and nonhuman primate infections are unknown. The cynomolgus macaque (Macaca fascicularis) model of M. tuberculosis infection closely mirrors the infection outcomes and pathology in human tuberculosis (TB). The present study used rituximab, an anti-CD20 antibody, to deplete B cells in M. tuberculosis-infected macaques to examine the contribution of B cells and humoral immunity to the control of TB in nonhuman primates during the acute phase of infection. While there was no difference in the overall pathology, disease profession, and clinical outcome between the rituximab-treated and untreated macaques in acute infection, analyzing individual granulomas revealed that B cell depletion resulted in altered local T cell and cytokine responses, increased bacterial burden, and lower levels of inflammation. There were elevated frequencies of T cells producing interleukin-2 (IL-2), IL-10, and IL-17 and decreased IL-6 and IL-10 levels within granulomas from B cell-depleted animals. The effects of B cell depletion varied among granulomas in an individual animal, as well as among animals, underscoring the previously reported heterogeneity of local immunologic characteristics of tuberculous granulomas in nonhuman primates. Taken together, our data clearly showed that B cells can modulate the local granulomatous response in M. tuberculosis-infected macaques during acute infection. The impact of these alterations on disease progression and outcome in the chronic phase remains to be determined. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  3. Haplo-identical transplantation for acquired severe aplastic anaemia in a multicentre prospective study.

    PubMed

    Xu, Lan-Ping; Wang, Shun-Qing; Wu, De-Pei; Wang, Jian-Min; Gao, Su-Jun; Jiang, Ming; Wang, Cun-Bang; Zhang, Xi; Liu, Qi-Fa; Xia, Ling-Hui; Wang, Xin; Huang, Xiao-Jun

    2016-10-01

    We conducted a prospective, multicentre study to confirm the feasibility of haplo-identical transplantation in treatment of severe aplastic anaemia (SAA) as salvage therapy, by analysing the outcomes of 101 patients who received haplo-identical transplantation between June 2012 and October 2015. All cases surviving for more than 28 d achieved donor myeloid engraftment. The median time for myeloid engraftment was 12 (range, 9-25) days and 15 (range, 7-101) days for platelets, with a cumulative platelet engraftment incidence of 94·1 ± 0·1%. With a median follow-up of 18·3 (3·0-43·6) months, recipients from haplo-identical transplantation had more cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD, 33·7% vs. 4·2%, P < 0·001), more chronic GVHD (22·4% vs. 6·6%, P = 0·014) at 1 year, but similar grade III-IV aGVHD (7·9% vs. 2·1%, P = 0·157), 3-year estimated overall survival (OS, 89·0% vs. 91·0%, P = 0·555) and failure-free survival (FFS, 86·8% vs. 80·3%, P = 0·659) when compared with 48 patients who received contemporaneous transplantation from matched related donors. Multivariate analysis showed no significant difference in engraftment and survival between the two cohorts. Both OS and FFS for the entire population correlated significantly with grades III-IV aGVHD. In conclusion, haplo-identical transplantation is a feasible choice for SAA with favourable outcomes. © 2016 John Wiley & Sons Ltd.

  4. Transient Treg depletion enhances therapeutic anti‐cancer vaccination

    PubMed Central

    Aston, Wayne J.; Chee, Jonathan; Khong, Andrea; Cleaver, Amanda L.; Solin, Jessica N.; Ma, Shaokang; Lesterhuis, W. Joost; Dick, Ian; Holt, Robert A.; Creaney, Jenette; Boon, Louis; Robinson, Bruce; Lake, Richard A.

    2016-01-01

    Abstract Introduction Regulatory T cells (Treg) play an important role in suppressing anti‐ immunity and their depletion has been linked to improved outcomes. To better understand the role of Treg in limiting the efficacy of anti‐cancer immunity, we used a Diphtheria toxin (DTX) transgenic mouse model to specifically target and deplete Treg. Methods Tumor bearing BALB/c FoxP3.dtr transgenic mice were subjected to different treatment protocols, with or without Treg depletion and tumor growth and survival monitored. Results DTX specifically depleted Treg in a transient, dose‐dependent manner. Treg depletion correlated with delayed tumor growth, increased effector T cell (Teff) activation, and enhanced survival in a range of solid tumors. Tumor regression was dependent on Teffs as depletion of both CD4 and CD8 T cells completely abrogated any survival benefit. Severe morbidity following Treg depletion was only observed, when consecutive doses of DTX were given during peak CD8 T cell activation, demonstrating that Treg can be depleted on multiple occasions, but only when CD8 T cell activation has returned to base line levels. Finally, we show that even minimal Treg depletion is sufficient to significantly improve the efficacy of tumor‐peptide vaccination. Conclusions BALB/c.FoxP3.dtr mice are an ideal model to investigate the full therapeutic potential of Treg depletion to boost anti‐tumor immunity. DTX‐mediated Treg depletion is transient, dose‐dependent, and leads to strong anti‐tumor immunity and complete tumor regression at high doses, while enhancing the efficacy of tumor‐specific vaccination at low doses. Together this data highlight the importance of Treg manipulation as a useful strategy for enhancing current and future cancer immunotherapies. PMID:28250921

  5. Cunninghamella bertholletiae Infection in a HLA-Haploidentical Hematopoietic Stem Cell Transplant Recipient with Graft Failure: Case Report and Review of the Literature.

    PubMed

    Luo, Chao; Wang, Jiasheng; Hu, Yongxian; Luo, Yi; Tan, Yamin; Jin, Aiyun; Wei, Bin; Hu, Huixian; Huang, He

    2016-10-01

    Cunninghamella bertholletiae as a rare cause of mucormycosis has been described almost exclusively in immunosuppressed patients such as hematopoietic stem cell transplant (HSCT) recipients. The infection is associated with high rates of mortality despite aggressive treatment. We describe a 40-year-old male with HLA-haploidentical HSCT developed fungal pneumonitis caused by C. bertholletiae complicated by graft failure and prolonged neutropenia. The patient died 102 days after HSCT despite early use of posaconazole and amphotericin B, which are believed to be the two most effective antifungal antibiotics against C. bertholletiae. The case highlights extreme unfavorable outcome in C. bertholletiae infection and neutropenia as a major risk factor.

  6. Increased transplant-related morbidity and mortality in CMV-seropositive patients despite highly effective prevention of CMV disease after allogeneic T-cell-depleted stem cell transplantation.

    PubMed

    Broers, A E; van Der Holt, R; van Esser, J W; Gratama, J W; Henzen-Logmans, S; Kuenen-Boumeester, V; Löwenberg, B; Cornelissen, J J

    2000-04-01

    We evaluated the efficacy, toxicity, and outcome of preemptive ganciclovir (GCV) therapy in 80 cytomegalovirus (CMV)-seropositive patients allografted between 1991 and 1996 and compared their outcome to 35 seronegative patients allografted during the same period. Both cohorts were comparable with respect to diagnosis and distribution of high- versus standard-risk patients. All patients received a stem cell graft from an HLA-identical sibling donor, and grafts were partially depleted of T cells in 109 patients. Patients were monitored for CMV antigenemia by leukocyte expression of the CMV-pp65 antigen. Fifty-two periods of CMV reactivation occurring in 30 patients were treated preemptively with GCV. A favorable response was observed in 48 of 50 periods, and only 2 patients developed CMV disease: 1 with esophagitis and 1 with pneumonia. Ten of 30 treated patients developed GCV-related neutropenia (less than 0.5 x 10(9)/L), which was associated with a high bilirubin at the start of GCV therapy. Overall survival at 5 years was 64% in the CMV-seronegative cohort and 40% in the CMV-seropositive cohort (P =.01). Increased treatment-related mortality accounted for inferior survival. CMV seropositivity proved an independent risk factor for developing acute graft-versus-host disease, and acute graft-versus-host disease predicted for higher treatment-related mortality and worse overall survival in a time-dependent analysis. We conclude that, although CMV disease can effectively be prevented by preemptive GCV therapy, CMV seropositivity remains a strong adverse risk factor for survival following partial T-cell-depleted allogeneic stem cell transplantation.

  7. Stem cell collection in unmanipulated HLA-haploidentical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilised blood and bone marrow for patients with haematologic malignancies: the impact of donor characteristics and procedural settings.

    PubMed

    Zhang, C; Chen, X-H; Zhang, X; Gao, L; Gao, L; Kong, P-Y; Peng, X-G; Sun, A-H; Gong, Y; Zeng, D-F; Wang, Q-Y

    2010-06-01

    Unmanipulated haploidentical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilised peripheral blood stem cells (G-PBSCs) and granulocyte-colony stimulating factor-mobilised bone marrow (G-BM) has been developed as an alternative transplantation strategy for patients with haematologic malignancies. However, little information is available about the factors predicting the outcome of peripheral blood stem cell (PBSC) collection and bone marrow (BM) harvest in this transplantation. The effects of donor characteristics and procedure factors on CD34(+) cell yield were investigated. A total of 104 related healthy donors received granulocyte-colony stimulating factor (G-CSF) followed by PBSC collection and BM harvest. Male donors had significantly higher yields compared with female donors. In multiple regression analysis for peripheral blood collection, age and flow rate were negatively correlated with cell yield, whereas body mass index, pre-aphaeresis white blood cell (WBC) and circulating immature cell (CIC) counts were positively correlated with cell yields. For BM harvest, age was negatively correlated with cell yields, whereas pre-BM collection CIC counts were positively correlated with cell yield. All donors achieved the final product of >or=6 x10(6) kg(-1) recipient body weight. This transplantation strategy has been shown to be a feasible approach with acceptable outcomes in stem cell collection for patients who received HLA-haploidentical/mismatched transplantation with combined G-PBSCs and G-BM. In donors with multiple high-risk characteristics for poor aphaeresis CD34(+) cell yield, BM was an alternative source.

  8. Factors affecting reconstitution of the T cell compartment in allogeneic haematopoietic cell transplant recipients.

    PubMed

    Fallen, P R; McGreavey, L; Madrigal, J A; Potter, M; Ethell, M; Prentice, H G; Guimarães, A; Travers, P J

    2003-11-01

    The factors affecting T cell reconstitution post haematopoietic cell transplantation (HCT) are not well characterised. We carried out a longitudinal analysis of T cell reconstitution in 32 HCT recipients during the first 12 months post transplant. We analysed reconstitution of naïve, memory and effector T cells, their diversity and monitored thymic output using TCR rearrangement excision circles (TRECs). Thymic-independent pathways were responsible for the rapid reconstitution of memory and effector T cells less than 6 months post HCT. Thymic-dependent pathways were activated between 6 and 12 months in the majority of patients with naïve T cell numbers increasing in parallel with TREC levels. Increasing patient age, chronic GVHD and T cell depletion (with or without pretransplant Campath-1H) predicted low TREC levels and slow naïve T cell recovery. Furthermore, increasing patient age also predicted high memory and effector T cell numbers. The effects of post HCT immunosuppression, total body irradiation, donor leucocyte infusions, T cell dose and post HCT infections on T cell recovery were also analysed. However, no effects of these single variables across a variety of different age, GVHD and T cell depletion groups were apparent. This study suggests that future analysis of the factors affecting T cell reconstitution and studies aimed at reactivating the thymus through therapeutic intervention should be analysed in age-, GVHD- and TCD-matched patient groups.

  9. Foxp3+ T cells inhibit antitumor immune memory modulated by mTOR inhibition.

    PubMed

    Wang, Yanping; Sparwasser, Tim; Figlin, Robert; Kim, Hyung L

    2014-04-15

    Inhibition of mTOR signaling enhances antitumor memory lymphocytes. However, pharmacologic mTOR inhibition also enhances regulatory T-cell (Treg) activity. To counter this effect, Treg control was added to mTOR inhibition in preclinical models. Tregs were controlled with CD4-depleting antibodies because CD4 depletion has high translational potential and already has a well-established safety profile in patients. The antitumor activity of the combination therapy was CD8 dependent and controlled growth of syngeneic tumors even when an adoptive immunotherapy was not used. Lymphocytes resulting from the combination therapy could be transferred into naïve mice to inhibit aggressive growth of lung metastases. The combination therapy enhanced CD8 memory formation as determined by memory markers and functional studies of immune recall. Removal of FoxP3-expressing T lymphocytes was the mechanism underlying immunologic memory formation following CD4 depletion. This was confirmed using transgenic DEREG (depletion of regulatory T cells) mice to specifically remove Foxp3(+) T cells. It was further confirmed with reciprocal studies where stimulation of immunologic memory because of CD4 depletion was completely neutralized by adoptively transferring tumor-specific Foxp3(+) T cells. Also contributing to tumor control, Tregs that eventually recovered following CD4 depletion were less immunosuppressive. These results provide a rationale for further study of mTOR inhibition and CD4 depletion in patients. ©2014 AACR.

  10. T cells which proliferate in response to concanavalin A include cells which proliferate in mixed leucocyte reactions.

    PubMed

    Watanabe, T; Fathman, C G; Coutinho, A

    1977-09-01

    Selection in long-term culture of alloreactive T cells, by successive in vitro restimulation with semi-allogeneic cells, results in primed responder cell populations which maintain full proliferative reactivity to allogeneic cells as well as to the T cell mitogens concanavalin A (Con A) and phytohemagglutinin (PHA) but are depleted of cells which can effect target cell destruction in either a specific or nonspecific manner. Con A-induced T cell blasts (selected by velocity sedimentation) can revert to small resting lymphocytes in the presence of inert "filler" cells. Con A blasts which have reverted, readily proliferate in response to Con A or allogeneic stimulator cells but are largely depleted of effector killer cells and PHA-responsive cells.

  11. Elimination of human T cell leukemia virus type-1-infected cells by neutralizing and antibody-dependent cellular cytotoxicity-inducing antibodies against human t cell leukemia virus type-1 envelope gp46.

    PubMed

    Tanaka, Yuetsu; Takahashi, Yoshiaki; Tanaka, Reiko; Kodama, Akira; Fujii, Hideki; Hasegawa, Atsuhiko; Kannagi, Mari; Ansari, Aftab A; Saito, Mineki

    2014-06-01

    Human T cell leukemia virus type-1 (HTLV-1) is prevalent worldwide with foci of high prevalence. However, to date no effective vaccine or drug against HTLV-1 infection has been developed. In efforts to define the role of antibodies in the control of HTLV-1 infection, we capitalized on the use of our previously defined anti-gp46 neutralizing monoclonal antibody (mAb) (clone LAT-27) and high titers of human anti-HTLV-1 IgG purified from HAM/TSP patients (HAM-IgG). LAT-27 and HAM-IgG completely blocked syncytium formation and T cell immortalization mediated by HTLV-1 in vitro. The addition of these antibodies to cultures of CD8(+) T cell-depleted peripheral blood mononuclear cells (PBMCs) from HAM/TSP patients at the initiation of culture not only decreased the numbers of Tax-expressing cells and the production of HTLV-1 p24 but also inhibited the spontaneous immortalization of T cells. Coculture of in vitro-HTLV-1-immortalized T cell lines with autologous PBMCs in the presence of LAT-27 or HAM-IgG, but not an F(ab')2 fragment of LAT-27 or nonneutralizing anti-gp46 mAbs, resulted in depletion of HTLV-1-infected cells. A 24-h (51)Cr release assay showed the presence of significant antibody-dependent cellular cytotoxicity (ADCC) activity in LAT-27 and HAM-IgG, but not F(ab')2 of LAT-27, resulting in the depletion of HTLV-1-infected T cells by autologous PBMCs. The depletion of natural killer (NK) cells from the effector PBMCs reduced this ADCC activity. Altogether, the present data demonstrate that the neutralizing and ADCC-inducing activities of anti-HTLV-1 antibodies are capable of reducing infection and eliminating HTLV-1-infected cells in the presence of autologous PBMCs.

  12. Critical role of CD4 T cells in maintaining lymphoid tissue structure for immune cell homeostasis and reconstitution.

    PubMed

    Zeng, Ming; Paiardini, Mirko; Engram, Jessica C; Beilman, Greg J; Chipman, Jeffrey G; Schacker, Timothy W; Silvestri, Guido; Haase, Ashley T

    2012-08-30

    Loss of the fibroblastic reticular cell (FRC) network in lymphoid tissues during HIV-1 infection has been shown to impair the survival of naive T cells and limit immune reconstitution after antiretroviral therapy. What causes this FRC loss is unknown. Because FRC loss correlates with loss of both naive CD4 and CD8 T-cell subsets and decreased lymphotoxin-β, a key factor for maintenance of FRC network, we hypothesized that loss of naive T cells is responsible for loss of the FRC network. To test this hypothesis, we assessed the consequences of antibody-mediated depletion of CD4 and CD8 T cells in rhesus macaques and sooty mangabeys. We found that only CD4 T-cell depletion resulted in FRC loss in both species and that this loss was caused by decreased lymphotoxin-β mainly produced by the CD4 T cells. We further found the same dependence of the FRC network on CD4 T cells in HIV-1-infected patients before and after antiretroviral therapy and in other immunodeficiency conditions, such as CD4 depletion in cancer patients induced by chemotherapy and irradiation. CD4 T cells thus play a central role in the maintenance of lymphoid tissue structure necessary for their own homeostasis and reconstitution.

  13. Critical role of CD4 T cells in maintaining lymphoid tissue structure for immune cell homeostasis and reconstitution

    PubMed Central

    Zeng, Ming; Paiardini, Mirko; Engram, Jessica C.; Beilman, Greg J.; Chipman, Jeffrey G.; Schacker, Timothy W.; Silvestri, Guido

    2012-01-01

    Loss of the fibroblastic reticular cell (FRC) network in lymphoid tissues during HIV-1 infection has been shown to impair the survival of naive T cells and limit immune reconstitution after antiretroviral therapy. What causes this FRC loss is unknown. Because FRC loss correlates with loss of both naive CD4 and CD8 T-cell subsets and decreased lymphotoxin-β, a key factor for maintenance of FRC network, we hypothesized that loss of naive T cells is responsible for loss of the FRC network. To test this hypothesis, we assessed the consequences of antibody-mediated depletion of CD4 and CD8 T cells in rhesus macaques and sooty mangabeys. We found that only CD4 T-cell depletion resulted in FRC loss in both species and that this loss was caused by decreased lymphotoxin-β mainly produced by the CD4 T cells. We further found the same dependence of the FRC network on CD4 T cells in HIV-1–infected patients before and after antiretroviral therapy and in other immunodeficiency conditions, such as CD4 depletion in cancer patients induced by chemotherapy and irradiation. CD4 T cells thus play a central role in the maintenance of lymphoid tissue structure necessary for their own homeostasis and reconstitution. PMID:22613799

  14. CD301b⁺ dermal dendritic cells drive T helper 2 cell-mediated immunity.

    PubMed

    Kumamoto, Yosuke; Linehan, Melissa; Weinstein, Jason S; Laidlaw, Brian J; Craft, Joseph E; Iwasaki, Akiko

    2013-10-17

    Unlike other types of T helper (Th) responses, whether the development of Th2 cells requires instruction from particular subset of dendritic cells (DCs) remains unclear. By using an in vivo depletion approach, we have shown that DCs expressing CD301b were required for the generation of Th2 cells after subcutaneous immunization with ovalbumin (OVA) along with papain or alum. CD301b⁺ DCs are distinct from epidermal or CD207⁺ dermal DCs (DDCs) and were responsible for transporting antigen injected subcutaneously with Th2-type adjuvants. Transient depletion of CD301b⁺ DCs resulted in less effective accumulation and decreased expression of CD69 by polyclonal CD4⁺ T cells in the lymph node. Moreover, despite intact cell division and interferon-γ production, CD301b⁺ DC depletion led to blunted interleukin-4 production by OVA-specific OT-II transgenic CD4⁺ T cells and significantly impaired Th2 cell development upon infection with Nippostrongylus brasiliensis. These results reveal CD301b⁺ DDCs as the key mediators of Th2 immunity. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Metabolic control of T-cell activation and death in SLE

    PubMed Central

    Fernandez, David; Perl, Andras

    2009-01-01

    Systemic lupus erythematosus (SLE) is characterized by abnormal T-cell activation and death, processes which are crucially dependent on the controlled production of reactive oxygen intermediates (ROI) and of ATP in mitochondria. The mitochondrial transmembrane potential (Δψm) has conclusively emerged as a critical checkpoint of ATP synthesis and cell death. Lupus T cells exhibit persistent elevation of Δψm or mitochondrial hyperpolarization (MHP) as well as depletion of ATP and glutathione which decrease activation-induced apoptosis and instead predispose T cells for necrosis, thus stimulating inflammation in SLE. NO-induced mitochondrial biogenesis in normal T cells accelerates the rapid phase and reduces the plateau of Ca2+ influx upon CD3/CD28 co-stimulation, thus mimicking the Ca2+ signaling profile of lupus T cells. Treatment of SLE patients with rapamycin improves disease activity, normalizes CD3/CD28-induced Ca2+ fluxing but fails to affect MHP, suggesting that altered Ca2+ fluxing is downstream or independent of mitochondrial dysfunction. Understanding the molecular basis and consequences of MHP is essential for controlling T-cell activation and death signaling in SLE. Lupus T cells exhibit mitochondrial dysfunctionMitochondrial hyperpolarization (MHP) and ATP depletion predispose lupus T cells to death by necrosis which is pro-inflammatoryMHP is caused by depletion of glutathione and exposure to nitric oxide (NO)NO-induced mitochondrial biogenesis regenerates the Ca2+ signaling profile of lupus T cellsRapamycin treatment normalizes Ca2+ fluxing but not MHP, suggesting that the mammalian target of rapamycin, acts as a sensor and effector of MHP in SLE PMID:18722557

  16. Skin effector memory T cells do not recirculate and provide immune protection in alemtuzumab-treated CTCL patients.

    PubMed

    Clark, Rachael A; Watanabe, Rei; Teague, Jessica E; Schlapbach, Christoph; Tawa, Marianne C; Adams, Natalie; Dorosario, Andrew A; Chaney, Keri S; Cutler, Corey S; Leboeuf, Nicole R; Carter, Joi B; Fisher, David C; Kupper, Thomas S

    2012-01-18

    Cutaneous T cell lymphoma (CTCL) is a cancer of skin-homing T cells with variants that include leukemic CTCL (L-CTCL), a malignancy of central memory T cells (T(CM)), and mycosis fungoides (MF), a malignancy of skin resident effector memory T cells (T(EM)). We report that low-dose alemtuzumab (αCD52) effectively treated patients with refractory L-CTCL but not MF. Alemtuzumab depleted all T cells in blood and depleted both benign and malignant T(CM) from skin, but a diverse population of skin resident T(EM) remained in skin after therapy. T cell depletion with alemtuzumab required the presence of neutrophils, a cell type frequent in blood but rare in normal skin. These data suggest that T(CM) were depleted because they recirculate between the blood and the skin, whereas skin resident T(EM) were spared because they are sessile and non-recirculating. After alemtuzumab treatment, skin T cells produced lower amounts of interleukin-4 and higher amounts of interferon-γ. Moreover, there was a marked lack of infections in alemtuzumab-treated L-CTCL patients despite the complete absence of T cells in the blood, suggesting that skin resident T(EM) can protect the skin from pathogens even in the absence of T cell recruitment from the circulation. Together, these data suggest that alemtuzumab may treat refractory L-CTCL without severely compromising the immune response to infection by depleting circulating T(CM) but sparing the skin resident T(EM) that provide local immune protection of the skin.

  17. CD4+ T-Cell-Independent Secondary Immune Responses to Pneumocystis Pneumonia

    PubMed Central

    de la Rua, Nicholas M.; Samuelson, Derrick R.; Charles, Tysheena P.; Welsh, David A.; Shellito, Judd E.

    2016-01-01

    Pneumocystis pneumonia is a major cause of morbidity and mortality among immunocompromised patients, especially in the context of HIV/AIDS. In the murine model of Pneumocystis pneumonia, CD4+ T-cells are required for clearance of a primary infection of Pneumocystis, but not the memory recall response. We hypothesized that the memory recall response in the absence of CD4+ T-cells is mediated by a robust memory humoral response, CD8+ T-cells, and IgG-mediated phagocytosis by alveolar macrophages. To investigate the role of CD8+ T-cells and alveolar macrophages in the immune memory response to Pneumocystis, mice previously challenged with Pneumocystis were depleted of CD8+ T-cells or alveolar macrophages prior to re-infection. Mice depleted of CD4+ T-cells prior to secondary challenge cleared Pneumocystis infection within 48 h identical to immunocompetent mice during a secondary memory recall response. However, loss of CD8+ T-cells or macrophages prior to the memory recall response significantly impaired Pneumocystis clearance. Specifically, mice depleted of CD8+ T-cells or alveolar macrophages had significantly higher fungal burden in the lungs. Furthermore, loss of alveolar macrophages significantly skewed the lung CD8+ T-cell response toward a terminally differentiated effector memory population and increased the percentage of IFN-γ+ CD8+ T-cells. Finally, Pneumocystis-infected animals produced significantly more bone marrow plasma cells and Pneumocystis-specific IgG significantly increased macrophage-mediated killing of Pneumocystis in vitro. These data suggest that secondary immune memory responses to Pneumocystis are mediated, in part, by CD8+ T-cells, alveolar macrophages, and the production of Pneumocystis-specific IgG. PMID:27242785

  18. Tenofovir alafenamide (TAF) does not deplete mitochondrial DNA in human T-cell lines at intracellular concentrations exceeding clinically relevant drug exposures.

    PubMed

    Stray, Kirsten M; Park, Yeojin; Babusis, Darius; Callebaut, Christian; Cihlar, Tomas; Ray, Adrian S; Perron, Michel

    2017-04-01

    HIV-infected patients treated with certain nucleoside reverse transcriptase inhibitors (NRTIs) have experienced adverse effects due to drug-related mitochondrial toxicity. Tenofovir alafenamide (TAF) is a novel prodrug of the NRTI tenofovir (TFV) with an improved safety profile compared to tenofovir disoproxil fumarate (TDF). Prior in vitro studies have demonstrated that the parent nucleotide TFV has no significant effects on mtDNA synthesis. This study investigated whether clinically relevant TAF and TDF exposures affect mtDNA content in human lymphocytes. First, activated or resting peripheral blood mononuclear cells (PBMCs), as well as MT-2 and Jurkat T-cell lines, were continuously treated with ddC for 10 days to establish their susceptibility to mtDNA depletion. PBMCs had low sensitivity to NRTI-mediated mtDNA depletion in vitro. In contrast, ddC treatment of rapidly dividing MT-2 and Jurkat cells resulted in a dose-dependent decrease in mtDNA. Therefore, these two T-cell lines were selected for evaluating TAF and TDF treatment effects. MT-2 and Jurkat cells were pulse-treated with TAF or TDF every 24 h for 10 days to mimic pharmacologically relevant drug exposures. Pulse treatment of cells with 3.3 μM TAF or 1.1 μM TDF for 10 days resulted in 2- to 7-fold greater steady-state intracellular TFV-diphosphate (TFV-DP) levels than those observed clinically in TAF- or TDF-treated patients. At these concentrations, no significant TAF- (106.7% and 84.1% of control; p = 0.77 and 0.12 for MT-2 and Jurkat, respectively) or TDF- (100.6% and 91.0% of control; p = 0.91 and 0.37, respectively) associated reduction in mtDNA content was observed compared with untreated control cells. This study demonstrates that, despite delivering higher intracellular levels of TFV-DP than TDF, TAF does not inhibit mtDNA synthesis in vitro at concentrations exceeding the clinically relevant intracellular drug exposures. Thus, TAF has a low potential for mitochondrial toxicity in

  19. TIGIT expressing CD4+T cells represent a tumor-supportive T cell subset in chronic lymphocytic leukemia

    PubMed Central

    Catakovic, Kemal; Gassner, Franz Josef; Ratswohl, Christoph; Zaborsky, Nadja; Rebhandl, Stefan; Schubert, Maria; Steiner, Markus; Gutjahr, Julia Christine; Pleyer, Lisa; Egle, Alexander; Hartmann, Tanja Nicole; Greil, Richard; Geisberger, Roland

    2018-01-01

    ABSTRACT While research on T cell exhaustion in context of cancer particularly focuses on CD8+ cytotoxic T cells, the role of inhibitory receptors on CD4+ T-helper cells have remained largely unexplored. TIGIT is a recently identified inhibitory receptor on T cells and natural killer (NK) cells. In this study, we examined TIGIT expression on T cell subsets from CLL patients. While we did not observe any differences in TIGIT expression in CD8+ T cells of healthy controls and CLL cells, we found an enrichment of TIGIT+ T cells in the CD4+ T cell compartment in CLL. Intriguingly, CLL patients with an advanced disease stage displayed elevated numbers of CD4+ TIGIT+ T cells compared to low risk patients. Autologous CLL-T cell co-culture assays revealed that depleting CD4+ TIGIT+ expressing T cells from co-cultures significantly decreased CLL viability. Accordingly, a supportive effect of TIGIT+CD4+ T cells on CLL cells in vitro could be recapitulated by blocking the interaction of TIGIT with its ligands using TIGIT-Fc molecules, which also impeded the T cell specific production of CLL-prosurvival cytokines. Our data reveal that TIGIT+CD4+T cells provide a supportive microenvironment for CLL cells, representing a potential therapeutic target for CLL treatment. PMID:29296521

  20. Higher frequencies of GARP(+)CTLA-4(+)Foxp3(+) T regulatory cells and myeloid-derived suppressor cells in hepatocellular carcinoma patients are associated with impaired T-cell functionality.

    PubMed

    Kalathil, Suresh; Lugade, Amit A; Miller, Austin; Iyer, Renuka; Thanavala, Yasmin

    2013-04-15

    The extent to which T-cell-mediated immune surveillance is impaired in human cancer remains a question of major importance, given its potential impact on the development of generalized treatments of advanced disease where the highest degree of heterogeneity exists. Here, we report the first global analysis of immune dysfunction in patients with advanced hepatocellular carcinoma (HCC). Using multi-parameter fluorescence-activated cell sorting analysis, we quantified the cumulative frequency of regulatory T cells (Treg), exhausted CD4(+) helper T cells, and myeloid-derived suppressor cells (MDSC) to gain concurrent views on the overall level of immune dysfunction in these inoperable patients. We documented augmented numbers of Tregs, MDSC, PD-1(+)-exhausted T cells, and increased levels of immunosuppressive cytokines in patients with HCC, compared with normal controls, revealing a network of potential mechanisms of immune dysregulation in patients with HCC. In dampening T-cell-mediated antitumor immunity, we hypothesized that these processes may facilitate HCC progression and thwart the efficacy of immunotherapeutic interventions. In testing this hypothesis, we showed that combined regimens to deplete Tregs, MDSC, and PD-1(+) T cells in patients with advanced HCC restored production of granzyme B by CD8(+) T cells, reaching levels observed in normal controls and also modestly increased the number of IFN-γ producing CD4(+) T cells. These clinical findings encourage efforts to restore T-cell function in patients with advanced stage disease by highlighting combined approaches to deplete endogenous suppressor cell populations that can also expand effector T-cell populations. ©2013 AACR.

  1. CD83 Antibody Inhibits Human B Cell Responses to Antigen as well as Dendritic Cell-Mediated CD4 T Cell Responses.

    PubMed

    Wong, Kuan Y; Baron, Rebecca; Seldon, Therese A; Jones, Martina L; Rice, Alison M; Munster, David J

    2018-05-15

    Anti-CD83 Ab capable of Ab-dependent cellular cytotoxicity can deplete activated CD83 + human dendritic cells, thereby inhibiting CD4 T cell-mediated acute graft-versus-host disease. As CD83 is also expressed on the surface of activated B lymphocytes, we hypothesized that anti-CD83 would also inhibit B cell responses to stimulation. We found that anti-CD83 inhibited total IgM and IgG production in vitro by allostimulated human PBMC. Also, Ag-specific Ab responses to immunization of SCID mice xenografted with human PBMC were inhibited by anti-CD83 treatment. This inhibition occurred without depletion of all human B cells because anti-CD83 lysed activated CD83 + B cells by Ab-dependent cellular cytotoxicity and spared resting (CD83 - ) B cells. In cultured human PBMC, anti-CD83 inhibited tetanus toxoid-stimulated B cell proliferation and concomitant dendritic cell-mediated CD4 T cell proliferation and expression of IFN-γ and IL-17A, with minimal losses of B cells (<20%). In contrast, the anti-CD20 mAb rituximab depleted >80% of B cells but had no effect on CD4 T cell proliferation and cytokine expression. By virtue of the ability of anti-CD83 to selectively deplete activated, but not resting, B cells and dendritic cells, with the latter reducing CD4 T cell responses, anti-CD83 may be clinically useful in autoimmunity and transplantation. Advantages might include inhibited expansion of autoantigen- or alloantigen-specific B cells and CD4 T cells, thus preventing further production of pathogenic Abs and inflammatory cytokines while preserving protective memory and regulatory cells. Copyright © 2018 by The American Association of Immunologists, Inc.

  2. iNOS expression in CD4+ T cells limits Treg induction by repressing TGFβ1: combined iNOS inhibition and Treg depletion unmask endogenous antitumor immunity.

    PubMed

    Jayaraman, Padmini; Alfarano, Matthew G; Svider, Peter F; Parikh, Falguni; Lu, Geming; Kidwai, Sarah; Xiong, Huabao; Sikora, Andrew G

    2014-12-15

    Expression of inducible nitric oxide synthase (iNOS) in different cellular compartments may have divergent effects on immune function. We used a syngeneic tumor model to functionally characterize the role of iNOS in regulation of CD4(+)FOXP3(+) regulatory T cells (Treg), and optimize the beneficial effects of iNOS inhibition on antitumor immunity. Wild-type (WT) or iNOS knockout mice bearing established MT-RET-1 melanoma were treated with the small-molecule iNOS inhibitor L-NIL and/or cyclophosphamide alone or in combination. The effect of iNOS inhibition or knockout on induction of Treg from mouse and human CD4(+) T cells in ex vivo culture was determined in parallel in the presence or absence of TGFβ1-depleting antibodies, and TGFβ1 levels were assessed by ELISA. Whereas intratumoral myeloid-derived suppressor cells (MDSC) were suppressed by iNOS inhibition or knockout, systemic and intratumoral FOXP3(+) Treg levels increased in tumor-bearing mice. iNOS inhibition or knockout similarly enhanced induction of Treg from activated cultured mouse splenocytes or purified human or mouse CD4(+) T cells in a TGFβ1-dependent manner. Although either iNOS inhibition or Treg depletion with low-dose cyclophosphamide alone had little effect on growth of established MT-RET1 melanoma, combination treatment potently inhibited MDSC and Treg, boosted tumor-infiltrating CD8(+) T-cell levels, and arrested tumor growth in an immune-dependent fashion. iNOS expression in CD4(+) T cells suppresses Treg induction by inhibiting TGFβ1 production. Our data suggest that iNOS expression has divergent effects on induction of myeloid and lymphoid-derived regulatory populations, and strongly support development of combinatorial treatment approaches that target these populations simultaneously. ©2014 American Association for Cancer Research.

  3. Granulocyte-mobilized bone marrow.

    PubMed

    Arcese, William; De Angelis, Gottardo; Cerretti, Raffaella

    2012-11-01

    In the last few years, mobilized peripheral blood has overcome bone marrow as a graft source, but, despite the evidence of a more rapid engraftment, the incidence of chronic graft-versus-host disease is significantly higher with, consequently, more transplant-related mortality on the long follow-up. Overall, the posttransplant outcome of mobilized peripheral blood recipients is similar to that of patients who are bone marrow grafted. More recently, the use of bone marrow after granulocyte colony-stimulating factor (G-CSF) donor priming has been introduced in the transplant practice. Herein, we review biological acquisitions and clinical results on the use of G-CSF-primed bone marrow as a source of hematopoietic stem cells (HSC) for allogeneic stem cell transplantation. G-CSF the increases the HSC compartment and exerts an intense immunoregulatory effect on marrow T-cells resulting in the shift from Th1 to Th2 phenotype with higher production of anti-inflammatory cytokines. The potential advantages of these biological effects have been translated in the clinical practice by using G-CSF primed unmanipulated bone marrow in the setting of transplant from human leukocyte antigen (HLA)-haploidentical donor with highly encouraging results. For patients lacking an HLA-identical sibling, the transplant of G-CSF primed unmanipulated bone marrow from a haploidentical donor combined with an intense in-vivo immunosuppression is a valid alternative achieving results that are well comparable with those reported for umbilical cord blood, HLA-matched unrelated peripheral blood/bone marrow or T-cell-depleted haploidentical transplant.

  4. Lack of clinical AIDS in SIV-infected sooty mangabeys with significant CD4+ T cell loss is associated with double-negative T cells.

    PubMed

    Milush, Jeffrey M; Mir, Kiran D; Sundaravaradan, Vasudha; Gordon, Shari N; Engram, Jessica; Cano, Christopher A; Reeves, Jacqueline D; Anton, Elizabeth; O'Neill, Eduardo; Butler, Eboneé; Hancock, Kathy; Cole, Kelly S; Brenchley, Jason M; Else, James G; Silvestri, Guido; Sodora, Donald L

    2011-03-01

    SIV infection of natural host species such as sooty mangabeys results in high viral replication without clinical signs of simian AIDS. Studying such infections is useful for identifying immunologic parameters that lead to AIDS in HIV-infected patients. Here we have demonstrated that acute, SIV-induced CD4(+) T cell depletion in sooty mangabeys does not result in immune dysfunction and progression to simian AIDS and that a population of CD3(+)CD4(-)CD8(-) T cells (double-negative T cells) partially compensates for CD4(+) T cell function in these animals. Passaging plasma from an SIV-infected sooty mangabey with very few CD4(+) T cells to SIV-negative animals resulted in rapid loss of CD4(+) T cells. Nonetheless, all sooty mangabeys generated SIV-specific antibody and T cell responses and maintained normal levels of plasma lipopolysaccharide. Moreover, all CD4-low sooty mangabeys elicited a de novo immune response following influenza vaccination. Such preserved immune responses as well as the low levels of immune activation observed in these animals were associated with the presence of double-negative T cells capable of producing Th1, Th2, and Th17 cytokines. These studies indicate that SIV-infected sooty mangabeys do not appear to rely entirely on CD4(+) T cells to maintain immunity and identify double-negative T cells as a potential subset of cells capable of performing CD4(+) T cell-like helper functions upon SIV-induced CD4(+) T cell depletion in this species.

  5. Recursion-based depletion of human immunodeficiency virus-specific naive CD4(+) T cells may facilitate persistent viral replication and chronic viraemia leading to acquired immunodeficiency syndrome.

    PubMed

    Tsukamoto, Tetsuo; Yamamoto, Hiroyuki; Okada, Seiji; Matano, Tetsuro

    2016-09-01

    Although antiretroviral therapy has made human immunodeficiency virus (HIV) infection a controllable disease, it is still unclear how viral replication persists in untreated patients and causes CD4(+) T-cell depletion leading to acquired immunodeficiency syndrome (AIDS) in several years. Theorists tried to explain it with the diversity threshold theory in which accumulated mutations in the HIV genome make the virus so diverse that the immune system will no longer be able to recognize all the variants and fail to control the viraemia. Although the theory could apply to a number of cases, macaque AIDS models using simian immunodeficiency virus (SIV) have shown that failed viral control at the set point is not always associated with T-cell escape mutations. Moreover, even monkeys without a protective major histocompatibility complex (MHC) allele can contain replication of a super infected SIV following immunization with a live-attenuated SIV vaccine, while those animals are not capable of fighting primary SIV infection. Here we propose a recursion-based virus-specific naive CD4(+) T-cell depletion hypothesis through thinking on what may happen in individuals experiencing primary immunodeficiency virus infection. This could explain the mechanism for impairment of virus-specific immune response in the course of HIV infection. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Differential Impact of In Vivo CD8+ T Lymphocyte Depletion in Controller versus Progressor Simian Immunodeficiency Virus-Infected Macaques.

    PubMed

    Chowdhury, Ankita; Hayes, Timothy L; Bosinger, Steven E; Lawson, Benton O; Vanderford, Thomas; Schmitz, Joern E; Paiardini, Mirko; Betts, Michael; Chahroudi, Ann; Estes, Jacob D; Silvestri, Guido

    2015-09-01

    Numerous studies have demonstrated that CD8(+) T lymphocytes suppress virus replication during human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) infection. However, the mechanisms underlying this activity of T cells remain incompletely understood. Here, we conducted CD8(+) T lymphocyte depletion in 15 rhesus macaques (RMs) infected intravenously (i.v.) with SIVmac239. At day 70 postinfection, the animals (10 progressors with high viremia and 5 controllers with low viremia) were CD8 depleted by i.v. administration of the antibody M-T807R1. As expected, CD8 depletion resulted in increased virus replication, more prominently in controllers than progressors, which correlated inversely with predepletion viremia. Of note, the feature of CD8(+) T lymphocyte predepletion that correlated best with the increase in viremia postdepletion was the level of CD8(+) T-bet(+) lymphocytes. We next found that CD8 depletion resulted in a homogenous increase of SIV RNA in superficial and mesenteric lymph nodes, spleen, and the gastrointestinal tract of both controllers and progressors. Interestingly, the level of SIV DNA increased postdepletion in both CD4(+) central memory T lymphocytes (TCM) and CD4(+) effector memory T lymphocytes (TEM) in progressor RMs but decreased in the CD4(+) TCM of 4 out of 5 controllers. Finally, we found that CD8 depletion is associated with a greater increase in CD4(+) T lymphocyte activation (measured by Ki-67 expression) in controllers than in progressors. Overall, these data reveal a differential impact of CD8(+) T lymphocyte depletion between controller and progressor SIV-infected RMs, emphasizing the complexity of the in vivo antiviral role of CD8(+) T lymphocytes. In this study, we further dissect the impact of CD8(+) T lymphocytes on HIV/SIV replication during SIV infection. CD8(+) T lymphocyte depletion leads to a relatively homogenous increase in viral replication in peripheral blood and tissues. CD8(+) T lymphocyte depletion

  7. Differential Impact of In Vivo CD8+ T Lymphocyte Depletion in Controller versus Progressor Simian Immunodeficiency Virus-Infected Macaques

    PubMed Central

    Chowdhury, Ankita; Hayes, Timothy L.; Bosinger, Steven E.; Lawson, Benton O.; Vanderford, Thomas; Schmitz, Joern E.; Paiardini, Mirko; Betts, Michael; Chahroudi, Ann; Estes, Jacob D.

    2015-01-01

    ABSTRACT Numerous studies have demonstrated that CD8+ T lymphocytes suppress virus replication during human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) infection. However, the mechanisms underlying this activity of T cells remain incompletely understood. Here, we conducted CD8+ T lymphocyte depletion in 15 rhesus macaques (RMs) infected intravenously (i.v.) with SIVmac239. At day 70 postinfection, the animals (10 progressors with high viremia and 5 controllers with low viremia) were CD8 depleted by i.v. administration of the antibody M-T807R1. As expected, CD8 depletion resulted in increased virus replication, more prominently in controllers than progressors, which correlated inversely with predepletion viremia. Of note, the feature of CD8+ T lymphocyte predepletion that correlated best with the increase in viremia postdepletion was the level of CD8+ T-bet+ lymphocytes. We next found that CD8 depletion resulted in a homogenous increase of SIV RNA in superficial and mesenteric lymph nodes, spleen, and the gastrointestinal tract of both controllers and progressors. Interestingly, the level of SIV DNA increased postdepletion in both CD4+ central memory T lymphocytes (TCM) and CD4+ effector memory T lymphocytes (TEM) in progressor RMs but decreased in the CD4+ TCM of 4 out of 5 controllers. Finally, we found that CD8 depletion is associated with a greater increase in CD4+ T lymphocyte activation (measured by Ki-67 expression) in controllers than in progressors. Overall, these data reveal a differential impact of CD8+ T lymphocyte depletion between controller and progressor SIV-infected RMs, emphasizing the complexity of the in vivo antiviral role of CD8+ T lymphocytes. IMPORTANCE In this study, we further dissect the impact of CD8+ T lymphocytes on HIV/SIV replication during SIV infection. CD8+ T lymphocyte depletion leads to a relatively homogenous increase in viral replication in peripheral blood and tissues. CD8+ T lymphocyte depletion resulted

  8. Lack of clinical AIDS in SIV-infected sooty mangabeys with significant CD4+ T cell loss is associated with double-negative T cells

    PubMed Central

    Milush, Jeffrey M.; Mir, Kiran D.; Sundaravaradan, Vasudha; Gordon, Shari N.; Engram, Jessica; Cano, Christopher A.; Reeves, Jacqueline D.; Anton, Elizabeth; O’Neill, Eduardo; Butler, Eboneé; Hancock, Kathy; Cole, Kelly S.; Brenchley, Jason M.; Else, James G.; Silvestri, Guido; Sodora, Donald L.

    2011-01-01

    SIV infection of natural host species such as sooty mangabeys results in high viral replication without clinical signs of simian AIDS. Studying such infections is useful for identifying immunologic parameters that lead to AIDS in HIV-infected patients. Here we have demonstrated that acute, SIV-induced CD4+ T cell depletion in sooty mangabeys does not result in immune dysfunction and progression to simian AIDS and that a population of CD3+CD4–CD8– T cells (double-negative T cells) partially compensates for CD4+ T cell function in these animals. Passaging plasma from an SIV-infected sooty mangabey with very few CD4+ T cells to SIV-negative animals resulted in rapid loss of CD4+ T cells. Nonetheless, all sooty mangabeys generated SIV-specific antibody and T cell responses and maintained normal levels of plasma lipopolysaccharide. Moreover, all CD4-low sooty mangabeys elicited a de novo immune response following influenza vaccination. Such preserved immune responses as well as the low levels of immune activation observed in these animals were associated with the presence of double-negative T cells capable of producing Th1, Th2, and Th17 cytokines. These studies indicate that SIV-infected sooty mangabeys do not appear to rely entirely on CD4+ T cells to maintain immunity and identify double-negative T cells as a potential subset of cells capable of performing CD4+ T cell–like helper functions upon SIV-induced CD4+ T cell depletion in this species. PMID:21317533

  9. CD8+ T cells induce thyroid epithelial cell hyperplasia and fibrosis.

    PubMed

    Yu, Shiguang; Fang, Yujiang; Sharav, Tumenjargal; Sharp, Gordon C; Braley-Mullen, Helen

    2011-02-15

    CD8(+) T cells can be important effector cells in autoimmune inflammation, generally because they can damage target cells by cytotoxicity. This study shows that activated CD8(+) T cells induce thyroid epithelial cell hyperplasia and proliferation and fibrosis in IFN-γ(-/-) NOD.H-2h4 SCID mice in the absence of CD4(+) T cells. Because CD8(+) T cells induce proliferation rather than cytotoxicity of target cells, these results describe a novel function for CD8(+) T cells in autoimmune disease. In contrast to the ability of purified CD8(+) T cells to induce thyrocyte proliferation, CD4(+) T cells or CD8 T cell-depleted splenocytes induced only mild thyroid lesions in SCID recipients. T cells in both spleens and thyroids highly produce TNF-α. TNF-α promotes proliferation of thyrocytes in vitro, and anti-TNF-α inhibits development of thyroid epithelial cell hyperplasia and proliferation in SCID recipients of IFN-γ(-/-) splenocytes. This suggests that targeting CD8(+) T cells and/or TNF-α may be effective for treating epithelial cell hyperplasia and fibrosis.

  10. Intravenous apoptotic spleen cell infusion induces a TGF-beta-dependent regulatory T-cell expansion

    PubMed Central

    Kleinclauss, François M.; Perruche, Sylvain; Masson, Emeline; De Carvalho Bittencourt, Marcelo; Biichle, Sabeha; Remy-Martin, Jean-Paul; Ferrand, Christophe; Martin, Mael; Bittard, Hugues; Chalopin, Jean-Marc; Seilles, Estelle; Tiberghien, Pierre; Saas, Philippe

    2006-01-01

    Apoptotic leukocytes are endowed with immunomodulatory properties that can be used to enhance hematopoietic engraftment and prevent graft-versus-host disease. This apoptotic cell-induced tolerogenic effect is mediated by host macrophages and not recipient dendritic cells or donor phagocytes present in the bone marrow graft as evidenced by selective cell depletion and trafficking experiments. Furthermore, apoptotic cell infusion is associated with TGF-β-dependent donor CD4+CD25+ T cell expansion. Such cells have a regulatory phenotype (CD62Lhigh and intracellular CTLA-4+), express high levels of Foxp3 mRNA and exert ex vivo suppressive activity through a cell-to-cell contact mechanism. In vivo CD25 depletion after apoptotic cell infusion prevents the apoptotic spleen cell-induced beneficial effects on engraftment and graft-versus-host disease occurrence. This highlights the role of regulatory T cells in the tolerogenic effect of apoptotic spleen cell infusion. This novel association between apoptosis and regulatory T cell expansion may also contribute to preventing deleterious auto-immune responses during normal turnover. PMID:15962005

  11. Critical roles of conventional dendritic cells in promoting T cell‐dependent hepatitis through regulating natural killer T cells

    PubMed Central

    Wang, J.; Cao, X.; Zhao, J.; Zhao, H.; Wei, J.; Li, Q.; Qi, X.; Yang, Z.; Wang, L.; Zhang, H.; Bai, L.; Wu, Z.; Zhao, L.; Hong, Z.

    2017-01-01

    Summary Dendritic cells (DCs) play critical roles in initiating and regulating innate immunity as well as adaptive immune responses. However, the role of conventional dendritic cells (cDCs) in concanavalin A (ConA)‐induced fulminant hepatitis is unknown. In this study, we demonstrated that depletion of cDCs using either CD11c‐diphtheria toxin receptor transgenic mice (DTR Tg) mice or anti‐CD11c antibody reduced the severity of liver injury significantly, indicating a detrimental role of cDCs in ConA‐induced hepatitis. We elucidated further the pathological role of cDCs as being the critical source of interleukin (IL)‐12, which induced the secretion of interferon (IFN)‐γ by natural killer (NK) T cells. Reconstitution of cDCs‐depleted mice with IL‐12 restored ConA‐induced hepatitis significantly. Furthermore, we determined that NK T cells were the target of DC‐derived IL‐12, and NK T cells contributed to liver inflammation and injury through production of IFN‐γ. In summary, our study demonstrated a novel function of cDCs in mediating ConA‐induced hepatitis through regulating IFN‐γ secretion of NK T cells in an IL‐12‐dependent fashion. Targeting cDCs might provide potentially therapeutic applications in treating autoimmune related liver diseases. PMID:27891589

  12. NK Cells Restrain Spontaneous Antitumor CD8+ T Cell Priming through PD-1/PD-L1 Interactions with Dendritic Cells.

    PubMed

    Iraolagoitia, Ximena L Raffo; Spallanzani, Raul G; Torres, Nicolás I; Araya, Romina E; Ziblat, Andrea; Domaica, Carolina I; Sierra, Jessica M; Nuñez, Sol Y; Secchiari, Florencia; Gajewski, Thomas F; Zwirner, Norberto W; Fuertes, Mercedes B

    2016-08-01

    Despite the classical function of NK cells in the elimination of tumor and of virus-infected cells, evidence for a regulatory role for NK cells has been emerging in different models of autoimmunity, transplantation, and viral infections. However, this role has not been fully explored in the context of a growing tumor. In this article, we show that NK cells can limit spontaneous cross-priming of tumor Ag-specific CD8(+) T cells, leading to reduced memory responses. After challenge with MC57 cells transduced to express the model Ag SIY (MC57.SIY), NK cell-depleted mice exhibited a significantly higher frequency of SIY-specific CD8(+) T cells, with enhanced IFN-γ production and cytotoxic capability. Depletion of NK cells resulted in a CD8(+) T cell population skewed toward an effector memory T phenotype that was associated with enhanced recall responses and delayed tumor growth after a secondary tumor challenge with B16.SIY cells. Dendritic cells (DCs) from NK cell-depleted tumor-bearing mice exhibited a more mature phenotype. Interestingly, tumor-infiltrating and tumor-draining lymph node NK cells displayed an upregulated expression of the inhibitory molecule programmed death ligand 1 that, through interaction with programmed death-1 expressed on DCs, limited DC activation, explaining their reduced ability to induce tumor-specific CD8(+) T cell priming. Our results suggest that NK cells can, in certain contexts, have an inhibitory effect on antitumor immunity, a finding with implications for immunotherapy in the clinic. Copyright © 2016 by The American Association of Immunologists, Inc.

  13. CD4+ T cells are required to contain early extrathoracic TB dissemination and sustain multi-effector functions of CD8+ T and CD3− lymphocytes

    PubMed Central

    Yao, Shuyu; Huang, Dan; Chen, Crystal Y.; Halliday, Lisa; Wang, Richard C.; Chen, Zheng W.

    2014-01-01

    The possibility that CD4+ T cells can act as “innate-like” cells to contain very-early M. tuberculosis (Mtb) dissemination and function as master helpers to sustain multiple effector functions of CD8+ T cells and CD3-negative lymphocytes during development of adaptive immunity against primary tuberculosis(TB) has not been demonstrated. We showed that pulmonary Mtb infection of CD4-depleted macaques surprisingly led to very-early extrathoracic Mtb dissemination, whereas CD4 deficiency clearly resulted in rapid TB progression. CD4 depletion during Mtb infection revealed the ability of CD8+ T cells to compensate and rapidly differentiate to Th17-like/Th1-like, and cytotoxic-like effectors, but these effector functions were subsequently unsustainable due to CD4 deficiency. While CD3-negative non-T lymphocytes in presence of CD4+ T cells developed predominant Th22-like and NK-like (perforin production) responses to Mtb infection, CD4 depletion abrogated these Th22-/NK-like effector functions and favored IL-17 production by CD3-negative lymphocytes. CD4-depleted macaques exhibited no or few pulmonary T effector cells constitutively producing IFN-γ, TNFα, IL-17, IL-22, and perforin at the endpoint of more severe TB, but presented pulmonary IL-4+ T effectors. TB granulomas in CD4-depleted macaques contained fewer IL-22+ and perforin+ cells despite presence of IL-17+ and IL-4+ cells. These results implicate previously-unknown “innate-like” ability of CD4+ T cells to contain extrathoracic Mtb dissemination at very early stage. Data also suggest that CD4+ T cells are required to sustain multiple effector functions of CD8+ T cells and CD3-negative lymphocytes and to prevent rapid TB progression during Mtb infection of nonhuman primates. PMID:24489088

  14. Therapeutic targeting of regulatory T cells enhances tumor-specific CD8+ T cell responses in Epstein–Barr virus associated nasopharyngeal carcinoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fogg, Mark; Murphy, John R.; Lorch, Jochen

    Epstein–Barr virus (EBV) is associated with multiple malignancies including nasopharyngeal carcinoma (NPC). In nasopharynx cancer, CD8+ T cells specific for EBV Nuclear Antigen-1 (EBNA-1) and Latent Membrane Protein 2 (LMP2) are important components of anti-tumor immunity since both are consistently expressed in NPC. We have previously shown that EBNA-1-specific CD8+ T cell responses were suppressed in NPC patients compared to healthy controls. We now find that CD8+ T cell responses specific for LMP2 are also abnormal in NPC patients, and both EBNA-1- and LMP2-specific responses are suppressed by regulatory T cells (Treg). EBNA-1 and LMP2-specific CD8+ T cell responses, asmore » well as immune control of EBV-infected cells in vitro, could be restored by the depletion of Tregs and by use of a clinically approved drug targeting Tregs. Thus, in vivo modulation of Tregs may be an effective means of enhancing these anti-tumor immune responses in NPC patients. - Highlights: • Viral proteins are tumor antigens in Epstein–Barr virus associated Nasopharyngeal Carcinoma. • CD8+ T cell responses against EBV proteins EBNA-1 and LMP2 are suppressed in NPC patients. • T regulatory cells are responsible for suppressing EBV immunity in NPC patients. • Depletion of Tregs with Ontak can rescue EBV-specific CD8+ T cell responses in NPC patients. • This clinically approved drug may be effective for enhancing anti-tumor immunity in NPC patients.« less

  15. Recombinant human interleukin-7 (CYT107) promotes T-cell recovery after allogeneic stem cell transplantation

    PubMed Central

    Goldberg, Jenna D.; Yuan, Jianda; Koehne, Guenther; Lechner, Lauren; Papadopoulos, Esperanza B.; Young, James W.; Jakubowski, Ann A.; Zaidi, Bushra; Gallardo, Humilidad; Liu, Cailian; Rasalan, Teresa; Wolchok, Jedd D.; Croughs, Therese; Morre, Michel; Devlin, Sean M.; van den Brink, Marcel R. M.

    2012-01-01

    Delays in immune recovery after allogeneic hematopoietic stem cell transplantation (allo-HSCT) are associated with increased risks of infection and relapse. IL-7 has a central role in T-cell development and survival and enhances immune recovery in murine models of allo-HSCT. We performed a phase 1 trial of r-hIL-7 (CYT107) in recipients of T-cell depleted allo-HSCTs. Twelve patients were treated with escalating doses of r-hIL-7 administered weekly for 3 weeks. The study drug was well tolerated with only one patient developing acute skin GVHD. At baseline, patients were profoundly lymphopenic. CYT107 induced a doubling in CD4+ and CD8+ T cells. The main effect of IL-7 was an expansion of effector memory T cells, the predominant subset identified in our patients. There was no significant effect on CD4+CD25+FoxP3+ T cells, NK, or B cells. Importantly, we not only saw quantitative increases in T cells after a short course of IL-7 but also demonstrated an increase in functional T cells, including viral-specific T cells that recognize CMV. Enhanced TCR diversity was also observed after treatment. Our results indicate that r-hIL-7 can enhance immune recovery after a T cell–depleted allo-HSCT without causing significant GVHD or other serious toxicity (www.clinicaltrials.gov; NCT00684008). PMID:23012326

  16. Recent thymic emigrants are preferentially incorporated only into the depleted T-cell pool.

    PubMed

    Houston, Evan G; Higdon, Lauren E; Fink, Pamela J

    2011-03-29

    Recent thymic emigrants (RTEs) are the youngest subset of peripheral T cells, and they differ functionally and phenotypically from the rest of the naïve T-cell pool. RTEs are present in the peripheral T-cell pool throughout life but are the most common subset of T cells in neonates and adults recovering from lymphoablation. Using a murine model to study the homeostasis of RTEs, we show that under lymphoreplete conditions, RTEs are at a competitive disadvantage to already established mature naïve (MN) T cells. This disadvantage may be caused by a defect in survival, because RTEs may transduce homeostatic signals inefficiently, and their ability to survive is enhanced with increased expression of IL-7 receptor or B-cell lymphoma 2 (Bcl-2). Conversely, under lymphopenic conditions, enhanced proliferation by RTEs allows them to out-compete their MN T-cell counterparts. These results suggest that in times of need, such as in neonates or lymphopenic adults, RTEs perform well to fill the gaps in the peripheral T-cell pool, but when the periphery already is full, many RTEs are not incorporated into the pool of recirculating lymphocytes.

  17. Skin effector memory T cells do not recirculate and provide immune protection in alemtuzumab-treated CTCL patients

    PubMed Central

    Clark, Rachael A.; Watanabe, Rei; Teague, Jessica E.; Schlapbach, Christoph; Tawa, Marianne C.; Adams, Natalie; Dorosario, Andrew A.; Chaney, Keri S.; Cutler, Corey S.; LeBoeuf, Nicole R.; Carter, Joi B.; Fisher, David C.; Kupper, Thomas S.

    2012-01-01

    CTCL is a cancer of skin homing T cells with variants that include leukemic CTCL (L-CTCL), a malignancy of central memory T cells (TCM), and mycosis fungoides (MF), a malignancy of skin resident effector memory T cells (TEM). We report that low-dose alemtuzumab (αCD52) effectively treated patients with refractory L-CTCL but not MF. Alemtuzumab depleted all T cells in blood and depleted both benign and malignant TCM from skin, but a diverse population of skin resident TEM remained in skin after therapy. T-cell depletion with alemtuzumab required the presence of neutrophils, a cell type frequent in blood but rare in normal skin. These data suggest that TCM were depleted because they recirculate between the blood and skin whereas skin resident TEM were spared because they are sessile and non-recirculating. After alemtuzumab treatment, skin T cells produced lower amounts of IL-4 and higher amounts of IFNγ. Moreover, there was a marked lack of infections in alemtuzumab-treated L-CTCL patients despite the complete absence of T cells in blood, suggesting that skin resident TEM can protect the skin from pathogens even in the absence of T cell recruitment from the circulation. Together, these data suggest that alemtuzumab may treat refractory L-CTCL without severely compromising the immune response to infection by depleting circulating TCM but sparing the skin resident TEM that provide local immune protection of the skin. PMID:22261031

  18. Availability of activated CD4+ T cells dictates the level of viremia in naturally SIV-infected sooty mangabeys.

    PubMed

    Klatt, Nichole R; Villinger, Francois; Bostik, Pavel; Gordon, Shari N; Pereira, Lara; Engram, Jessica C; Mayne, Ann; Dunham, Richard M; Lawson, Benton; Ratcliffe, Sarah J; Sodora, Donald L; Else, James; Reimann, Keith; Staprans, Silvija I; Haase, Ashley T; Estes, Jacob D; Silvestri, Guido; Ansari, Aftab A

    2008-06-01

    Naturally SIV-infected sooty mangabeys (SMs) remain asymptomatic despite high virus replication. Elucidating the mechanisms underlying AIDS resistance of SIV-infected SMs may provide crucial information to better understand AIDS pathogenesis. In this study, we assessed the determinants of set-point viremia in naturally SIV-infected SMs, i.e., immune control of SIV replication versus target cell limitation. We depleted CD4+ T cells in 6 naturally SIV-infected SMs by treating with humanized anti-CD4 mAb (Cdr-OKT4A-huIgG1). CD4+ T cells were depleted almost completely in blood and BM and at variable levels in mucosal tissues and LNs. No marked depletion of CD14+ monocytes was observed. Importantly, CD4+ T cell depletion was associated with a rapid, significant decline in viral load, which returned to baseline level at day 30-45, coincident with an increased fraction of proliferating and activated CD4+ T cells. Throughout the study, virus replication correlated with the level of proliferating CD4+ T cells. CD4+ T cell depletion did not induce any changes in the fraction of Tregs or the level of SIV-specific CD8+ T cells. Our results suggest that the availability of activated CD4+ T cells, rather than immune control of SIV replication, is the main determinant of set-point viral load during natural SIV infection of SMs.

  19. Role of T cells in sex differences in syngeneic bone marrow transfers.

    PubMed

    Raveche, E S; Santoro, T; Brecher, G; Tjio, J H

    1985-11-01

    Transferred marrow cells will proliferate in normal mice not exposed to irradiation or any other type of stem cell depletion when five consecutive transfers of 40 million cells are given. Approximately 25% of the mitotic cells are of male donor origin observed cytogenetically in all of the female recipient spleens and marrow analyzed from two weeks to one and one-half years after transfusions. Male donor stem cells are accepted and form a stable component of the self-renewing stem cell pool. In contrast, only 5% female cells are found in male recipients. This sex difference in engraftment is not hormonal since castration of recipients does not alter the percentage of donor cells. Rigorous T depletion of female donor bone marrow, however, increases the percentage of donor engraftment to the level observed when male marrow, either whole or T depleted, is transferred to female recipients. The success of T-depleted female stem cells to seed male recipients is observed in both C57BL/6, a responder strain in which females readily respond to the H-Y antigen as manifest by skin graft rejection, and CBA/J, a strain in which females do not readily respond to H-Y. In addition, recipient nude BALB/c males, which lack a thymus, fail to accept whole bone marrow from BALB/c females. However, male bone marrow cells seed BALB/c nude females. These studies demonstrate that the poor engraftment of female cells in transfused male recipients is abrogated by the removal of T cells from the donor female marrow.

  20. Comparison of transplant-specific prognostic scoring systems in haploidentical transplantation for myelodysplastic syndrome.

    PubMed

    Shin, Seung-Hwan; Jeon, Young-Woo; Yoon, Jae-Ho; Yahng, Seung-Ah; Lee, Sung-Eun; Cho, Byung-Sik; Eom, Ki-Seong; Lee, Seok; Kim, Hee-Je; Min, Chang-Ki; Cho, Seok-Goo; Kim, Dong-Wook; Lee, Jong-Wook; Min, Woo-Sung; Kim, Yoo-Jin

    2018-05-14

    We intended to identify the predictive abilities of recently published transplant-specific prognostic scoring systems in myelodysplastic syndrome (MDS) patients receiving haploidentical transplantation. The outcomes of 73 MDS patients receiving haploidentical transplantation were analyzed, according to the MTPSS, the TRI, and the CIBMTR scoring systems. The median age of patients at transplantation was 50 (range, 19-69) years. The IPSS-R cytogenetic risks of very good/good, intermediate, and poor/very poor were respectively observed in 35 (48.0%), 25 (34.2%), and 13 (17.8%) patients, including 4 (5.5%) with a monosomal karyotype. Pre-transplant treatment failure and high (≥ 3) HCT-CI were observed in 30 (41.1%) and 35 (48.0%) patients, respectively. With survivor's median follow-up of 42.3 months, the overall survival rate at 4 years of all patients was 65.5% (95% CI, 52.4-75.9). The MTPSS (100%, 77.3%, 62.5%, and 42.0% at 4 years; P = 0.02) and the TRI (100%, 79.9%, 76.0%, and 17.1% at 4 years; P < 0.01) differentiate proportionally overall survival rates according to their 4 risk groups, whereas the CIBMTR scoring system did not (P = 0.17). Our results suggest the potential ability of the MPTSS and the TRI as prognostic tools for MDS patients receiving haploidentical transplantation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. Myeloid Conditioning with c-kit-Targeted CAR-T Cells Enables Donor Stem Cell Engraftment.

    PubMed

    Arai, Yasuyuki; Choi, Uimook; Corsino, Cristina I; Koontz, Sherry M; Tajima, Masaki; Sweeney, Colin L; Black, Mary A; Feldman, Steven A; Dinauer, Mary C; Malech, Harry L

    2018-05-02

    We report a novel approach to bone marrow (BM) conditioning using c-kit-targeted chimeric antigen receptor T (c-kit CAR-T) cells in mice. Previous reports using anti-c-kit or anti-CD45 antibody linked to a toxin such as saporin have been promising. We developed a distinctly different approach using c-kit CAR-T cells. Initial studies demonstrated in vitro killing of hematopoietic stem cells by c-kit CAR-T cells but poor expansion in vivo and poor migration of CAR-T cells into BM. Pre-treatment of recipient mice with low-dose cyclophosphamide (125 mg/kg) together with CXCR4 transduction in the CAR-T cells enhanced trafficking to and expansion in BM (<1%-13.1%). This resulted in significant depletion of the BM c-kit + population (9.0%-0.1%). Because congenic Thy1.1 CAR-T cells were used in the Thy1.2-recipient mice, anti-Thy1.1 antibody could be used to deplete CAR-T cells in vivo before donor BM transplant. This achieved 20%-40% multilineage engraftment. We applied this conditioning to achieve an average of 28% correction of chronic granulomatous disease mice by wild-type BM transplant. Our findings provide a proof of concept that c-kit CAR-T cells can achieve effective BM conditioning without chemo-/radiotherapy. Our work also demonstrates that co-expression of a trafficking receptor can enhance targeting of CAR-T cells to a designated tissue. Published by Elsevier Inc.

  2. [Chimeric antigen receptors T cells in treatment of a relapsed pediatric acute lymphoblastic leukemia, relapse after allogenetic hematopoietic stem cell transplantation: case report and review of literature review].

    PubMed

    Zuo, Yingxi; Wang, Jingbo; Lu, Aidong; Jia, Yueping; Wu, Jun; Dong, Lujia; Chang, Lungji; Zhang, Leping

    2016-02-01

    To evaluate the safety and efficacy of chimeric antigen receptors T cells (CAR-T) in childhood acute B lymphoblastic leukemia (B-ALL). A relapsed B-ALL child after allogeneic hematopoietic stem cell transplantation (allo-HSCT) was treated with CAR-T, and the related literatures were reviewed. An 11-year-old girl with TEL-AML1 fusion gene positive BALL who suffered a bone marrow relapse 28 months after remission from conventional chemotherapy. During the second remission, the patient received haploidentical allo-HSCT. She relapsed with detectable TEL-AML1 fusion gene even after chemotherapy and donor leukocyte infusions. She received an experimental donor-derived fourth generation CD19 CAR-T therapy. After infusion of 1 × 10(6)/kg CAR-T cells, she experienced only mild or moderate cytokine-release syndrome and the minimal residual disease turned negative. Then three maintenance of CAR-T cell infusions [(0.83-1.65)×10(6)/kg] was administered, and the disease-free survival had lasted for 10 months. However, the TEL-AML1 copies in her blood still increased and she died with leukemia relapse after additional CAR-T cell infusion. Treatment of relapsed B-ALL with the fourth generation CAR-T cells directed against CD19 was effective and safe. CAR-T therapy is a novel therapeutic approach that could be useful for patients with relapsed and refractory B-ALL who have failed all other treatment options.

  3. Depletion of CD8+ cells does not affect the lifespan of productively infected cells during pathogenic sivmac239 infection of rhesus macaques

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shudo, Emi; Ribeiro, Ruy M; Perelson, Alan S

    2008-01-01

    While CD8+ T cell responses are clearly important in anti-viral immunity during HIV/SIV infection, the mechanisms by which CD8+ T cells induce this effect remain poorly understood, as emphasized by the failure of the Merck adenovirus-based, cytotoxic T lymphocyte (CTL)-inducing AIDS vaccine in a large phase IIb clinical trial. In this study, we measured the in vivo effect of CD8+ lymphocytes on the lifespan of productively infected cells during chronic SIVmac239 infection of rhesus macaques by treating two groups of animals (i.e., CD8+ lymphocyte-depleted or controls) with antiretroviral therapy (PMPA and FTC). The lifespan of productively infected cells was calculatedmore » based on the slope of the decline of SIV plasma viremia using a well-accepted mathematical model. We found that, in both early (i.e., day 57 post-inoculation) and late (i.e., day 177 post-inoculation) chronic SIV infection, depletion of CD8+ lymphocytes did not result in an increased lifespan of productively infected cells in vivo. This result indicates that direct killing of cells producing virus is unlikely to be a major mechanism underlying the anti-viral effect of CD8+ T cells during SIV infection. These results have profound implications for the development of AIDS vaccines.« less

  4. Monitoring α4β7 integrin expression on circulating CD4+ T cells as a surrogate marker for tracking intestinal CD4+ T cell loss in SIV infection

    PubMed Central

    Wang, Xiaolei; Xu, Huanbin; Gill, Amy F.; Pahar, Bapi; Kempf, Doty; Rasmussen, Terri; Lackner, Andrew A.; Veazey, Ronald S.

    2013-01-01

    Intestinal CD4+ T cells are rapidly and profoundly depleted in HIV-infected patients and SIV-infected macaques. However, monitoring intestinal cells in humans is difficult, and identifying surrogate markers in the blood, which correlate with loss or restoration of intestinal CD4+ T cells could be helpful in monitoring the success of therapeutic strategies and vaccine candidates. Recent studies indicate HIV utilizes the intestinal homing molecule α4β7 for attachment and signaling of CD4+ T cells, suggesting this molecule may play a central role in HIV pathogenesis. Here we compared β7HIGH integrin expression on CD4+ T cells in blood with loss of CD4+ T cells in the intestine of macaques throughout SIV infection. The loss of β7HIGH CD4+ T cells in blood closely paralleled the loss of intestinal CD4+ T cells, and proved to be a more reliable marker of intestinal CD4+ T cell loss than monitoring CCR5+ memory CD4+ T cells. These data are consistent with a recent hypothesis that α4β7 plays a role in the selective depletion of intestinal CD4+ T cells, and indicate that monitoring β7HIGH expression on CD4+ T cells in the blood may be a useful surrogate for estimating intestinal CD4+ T cell loss and restoration in HIV-infected patients. PMID:19710637

  5. Availability of activated CD4+ T cells dictates the level of viremia in naturally SIV-infected sooty mangabeys

    PubMed Central

    Klatt, Nichole R.; Villinger, Francois; Bostik, Pavel; Gordon, Shari N.; Pereira, Lara; Engram, Jessica C.; Mayne, Ann; Dunham, Richard M.; Lawson, Benton; Ratcliffe, Sarah J.; Sodora, Donald L.; Else, James; Reimann, Keith; Staprans, Silvija I.; Haase, Ashley T.; Estes, Jacob D.; Silvestri, Guido; Ansari, Aftab A.

    2008-01-01

    Naturally SIV-infected sooty mangabeys (SMs) remain asymptomatic despite high virus replication. Elucidating the mechanisms underlying AIDS resistance of SIV-infected SMs may provide crucial information to better understand AIDS pathogenesis. In this study, we assessed the determinants of set-point viremia in naturally SIV-infected SMs, i.e., immune control of SIV replication versus target cell limitation. We depleted CD4+ T cells in 6 naturally SIV-infected SMs by treating with humanized anti-CD4 mAb (Cdr-OKT4A-huIgG1). CD4+ T cells were depleted almost completely in blood and BM and at variable levels in mucosal tissues and LNs. No marked depletion of CD14+ monocytes was observed. Importantly, CD4+ T cell depletion was associated with a rapid, significant decline in viral load, which returned to baseline level at day 30–45, coincident with an increased fraction of proliferating and activated CD4+ T cells. Throughout the study, virus replication correlated with the level of proliferating CD4+ T cells. CD4+ T cell depletion did not induce any changes in the fraction of Tregs or the level of SIV-specific CD8+ T cells. Our results suggest that the availability of activated CD4+ T cells, rather than immune control of SIV replication, is the main determinant of set-point viral load during natural SIV infection of SMs. PMID:18497876

  6. EFFECT OF LIPOSOMAL CLODRONATE-DEPENDENT DEPLETION OF PROFESSIONAL ANTIGEN PRESENTING CELLS ON NUMBERS AND PHENOTYPE OF CANINE CD4+CD25+FOXP3+ REGULATORY T CELLS

    PubMed Central

    Weaver, Kriston F.; Stokes, John V.; Gunnoe, Sagen A.; Follows, Joyce S.; Shafer, Lydia; Ammari, Mais G.; Archer, Todd M.; Thomason, John M.; Mackin, Andrew J.; Pinchuk, Lesya M.

    2015-01-01

    Regulatory T cells (Tregs) are known to control autoreactivity during and subsequent to the development of the peripheral immune system. Professional antigen presenting cells (APCs), dendritic cells (DCs) and monocytes, have an important role in inducing Tregs. For the first time, this study evaluated proportions and phenotypes of Tregs in canine peripheral blood depleted of professional APCs, utilizing liposomal clodronate (LC) and multicolor flow cytometry analysis. Our results demonstrate that LC exposure promoted short term decreases followed by significant increases in the proportions or absolute numbers of CD4+CD25+FOXP3+ Tregs in dogs. In general, the LC-dependent Treg fluctuations were similar to the changes in the levels of CD14+ monocytes in Walker hounds. However, the proportions of monocytes showed more dramatic changes compared to the proportions of Tregs that were visually unchanged after LC treatment over the study period. At the same time, absolute Treg numbers showed, similarly to the levels of CD14+ monocytes, significant compensatory gains as well as the recovery during the normalization period. We confirm the previous data that CD4+ T cells with the highest CD25 expression were highly enriched for FOXP3. Furthermore, for the first time, we report that CD4+CD25lowFOXP3+ is the major regulatory T cell subset affected by LC exposure. The increases within the lowest CD25 expressers of CD4+FOXP3+ cells together with compensatory gains in the proportion of CD14+ monocytes during compensatory and normalization periods suggest the possible direct or indirect roles of monocytes in active recruitment and generation of Tregs from naïve CD4+ T cells. PMID:25950023

  7. Downregulation of proapoptotic Bim augments IL-2-independent T-cell transformation by human T-cell leukemia virus type-1 Tax.

    PubMed

    Higuchi, Masaya; Takahashi, Masahiko; Tanaka, Yuetsu; Fujii, Masahiro

    2014-12-01

    Human T-cell leukemia virus type 1 (HTLV-1), an etiological agent of adult T-cell leukemia, immortalizes and transforms primary human T cells in vitro in both an interleukin (IL)-2-dependent and IL-2-independent manner. Expression of the HTLV-1 oncoprotein Tax transforms the growth of the mouse T-cell line CTLL-2 from being IL-2-dependent to IL-2-independent. Withdrawal of IL-2 from normal activated T cells induces apoptosis, which is mediated through the inducible expression of several proapoptotic proteins, including Bim. In this study, we found that Tax protects IL-2-depleted T cells against Bim-induced apoptosis. Withdrawal of IL-2 from CTLL-2 cells induced a prominent increase in the level of Bim protein in CTLL-2 cells, but not in Tax-transformed CTLL-2 cells. This inhibition of Bim in Tax-transformed CTLL-2 cells was mediated by two mechanisms: downregulation of Bim mRNA and posttranscriptional reduction of Bim protein. Transient expression of Tax in CTLL-2 cells also inhibited IL-2 depletion-induced expression of Bim, however, this decrease in Bim protein expression was not due to downregulation of Bim mRNA, thus indicating that Bim mRNA downregulation in Tax-transformed CTLL-2 occurs only after long-term expression of Tax. Transient expression of Tax in CTLL-2 cells also induced Erk activation, however, this was not involved in the reduction of Bim protein. Knockdown of Bim expression in CTLL-2 cells augmented Tax-induced IL-2-independent transformation. HTLV-1 infection of human T cells also reduced their levels of Bim protein, and restoring Bim expression in HTLV-1-infected cells reduced their proliferation by inducing apoptosis. Taken together, these results indicate that Tax-induced downregulation of Bim in HTLV-1-infected T cells promotes their IL-2-independent growth, thereby supporting the persistence of HTLV-1 infection in vivo. © 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  8. Reconstruction of the immune system after unrelated or partially matched T-cell-depleted bone marrow transplantation in children: immunophenotypic analysis and factors affecting the speed of recovery.

    PubMed

    Kook, H; Goldman, F; Padley, D; Giller, R; Rumelhart, S; Holida, M; Lee, N; Peters, C; Comito, M; Huling, D; Trigg, M

    1996-08-01

    We prospectively studied immune reconstitution in 102 children who underwent T-lymphocyte depleted bone marrow transplants using either closely matched unrelated donors or partially matched familial donors by assaying total lymphocyte counts (TLC), T-cell subsets, B cells, and natural killer cells. TLC, CD3+, and CD4+ T-cell counts remained depressed until 2 to 3 years posttransplant, whereas CD8+ T-cell counts normalized by 18 months, resulting in an inverted CD4:CD8 ratio until 12 months posttransplant. Although the percentage of NK cells was elevated early posttransplant, their absolute numbers remained normal. CD20+ B cells were depressed until 12 to 18 months posttransplant. Factors affecting immunophenotypic recovery were analyzed by nonparametric statistics. Younger patients tended to have higher TLC posttransplant. Higher marrow cell doses were not associated with hastened immunophenotypic recovery. Graft-versus-host disease (GVHD) and/or its treatment significantly delayed the immune reconstitution of CD3+, CD4+, and CD20+ cells. The presence of cytomegalovirus was associated with increased CD8+ counts and a decrease in the percentages of CD4+ and CD20+ cells.

  9. Massive infection and loss of CD4+ T cells occurs in the intestinal tract of neonatal rhesus macaques in acute SIV infection.

    PubMed

    Wang, Xiaolei; Rasmussen, Terri; Pahar, Bapi; Poonia, Bhawna; Alvarez, Xavier; Lackner, Andrew A; Veazey, Ronald S

    2007-02-01

    Rapid, profound, and selective depletion of memory CD4+ T cells has now been confirmed to occur in simian immunodeficiency virus (SIV)-infected adult macaques and human immunodeficiency virus (HIV)-infected humans. Within days of infection, marked depletion of memory CD4+ T cells occurs primarily in mucosal tissues, the major reservoir for memory CD4+ T cells in adults. However, HIV infection in neonates often results in higher viral loads and rapid disease progression, despite the paucity of memory CD4+ T cells in the peripheral blood. Here, we examined the immunophenotype of CD4+ T cells in normal and SIV-infected neonatal macaques to determine the distribution of naive and memory T-cell subsets in tissues. We demonstrate that, similar to adults, neonates have abundant memory CD4+ T cells in the intestinal tract and spleen and that these are selectively infected and depleted in primary SIV infection. Within 12 days of SIV infection, activated (CD69+), central memory (CD95+CD28+) CD4+ T cells are marked and persistently depleted in the intestine and other tissues of neonates compared with controls. The results in dicate that "activated" central memory CD4+ T cells are the major target for early SIV infection and CD4+ T cell depletion in neonatal macaques.

  10. Combination Effect of Regulatory T-Cell Depletion and Ionizing Radiation in Mouse Models of Lung and Colon Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Son, Cheol-Hun; Department of Biochemistry, Pusan National University School of Medicine, Yangsan; Bae, Jae-Ho

    2015-06-01

    Purpose: To investigate the potential of low-dose cyclophosphamide (LD-CTX) and anti-CD25 antibody to prevent activation of regulatory T cells (Tregs) during radiation therapy. Methods and Materials: We used LD-CTX and anti-CD25 monoclonal antibody as a means to inhibit Tregs and improve the therapeutic effect of radiation in a mouse model of lung and colon cancer. Mice were irradiated on the tumor mass of the right leg and treated with LD-CTX and anti-CD25 antibody once per week for 3 weeks. Results: Combined treatment of LD-CTX or anti-CD25 antibody with radiation significantly decreased Tregs in the spleen and tumor compared with control andmore » irradiation only in both lung and colon cancer. Combinatorial treatments resulted in a significant increase in the effector T cells, longer survival rate, and suppressed irradiated and distal nonirradiated tumor growth. Specifically, the combinatorial treatment of LD-CTX with radiation resulted in outstanding regression of local and distant tumors in colon cancer, and almost all mice in this group survived until the end of the study. Conclusions: Our results suggest that Treg depletion strategies may enhance radiation-mediated antitumor immunity and further improve outcomes after radiation therapy.« less

  11. Internalization of rituximab and the efficiency of B Cell depletion in rheumatoid arthritis and systemic lupus erythematosus.

    PubMed

    Reddy, Venkat; Cambridge, Geraldine; Isenberg, David A; Glennie, Martin J; Cragg, Mark S; Leandro, Maria

    2015-05-01

    Rituximab, a type I anti-CD20 monoclonal antibody (mAb), induces incomplete B cell depletion in some patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), thus contributing to a poor clinical response. The mechanisms of this resistance remain elusive. The purpose of this study was to determine whether type II mAb are more efficient than type I mAb at depleting B cells from RA and SLE patients, whether internalization influences the efficiency of depletion, and whether Fcγ receptor type IIb (FcγRIIb) and the B cell receptor regulate this internalization process. We used an in vitro whole blood B cell-depletion assay to assess the efficiency of depletion, flow cytometry to study cell surface protein expression, and surface fluorescence-quenching assays to assess rituximab internalization, in samples from patients with RA and patients with SLE. Paired t-test or Mann-Whitney U test was used to compare groups, and Spearman's rank correlation test was used to assess correlation. We found that type II mAb internalized significantly less rituximab than type I mAb and depleted B cells from patients with RA and SLE at least 2-fold more efficiently than type I mAb. Internalization of rituximab was highly variable between patients, was regulated by FcγRIIb, and inversely correlated with cytotoxicity in whole blood B cell-depletion assays. The lowest levels of internalization were seen in IgD- B cells, including postswitched (IgD-CD27+) memory cells. Internalization of type I anti-CD20 mAb was also partially inhibited by anti-IgM stimulation. Variability in internalization of rituximab was observed and was correlated with impaired B cell depletion. Therefore, slower-internalizing type II mAb should be considered as alternative B cell-depleting agents for the treatment of RA and SLE. © 2015 The Authors. Arthritis & Rheumatology is published by Wiley Periodicals, Inc. on behalf of the American College of Rheumatology.

  12. Nephrogenic diabetes insipidus in initial stage of acute lymphoblastic leukemia and relapse after haploidentical hematopoietic stem-cell transplantation: A case report.

    PubMed

    Li, Dezhi; Liu, Qian; Feng, Zhifang; Zhang, Qi; Feng, Saran

    2018-06-01

    Nephrogenic diabetes insipidus (NDI) rarely presents in the initial stage of acute lymphoblastic leukemia (ALL) and relapse due to renal infiltration is also rare. A 19-year-old man presented with weakness, polydipsia, and polyuria for 1 month. NDI was diagnosed with insignificant response to a water deprivation test after stimulation with vasopressin injection. Bone marrow examination combined with immunophenotypic analysis, cerebrospinal cytology, and abdominal ultrasonography confirmed the diagnoses of precursor B cell ALL with renal infiltration. The patient accepted standardized combination chemotherapy and ultimately had sustained remission, and his polydipsia and polyuria disappeared after 3 days of treatment. The ALL relapsed 1 year later and he received haploidentical stem cell transplantation (haplo-SCT) from his father. One year later, he again developed NDI, with bilateral renal enlargement because of extramedullary relapse, leading to subsequent death. This case demonstrates unusual early renal involvement in ALL presenting with initial NDI. Interestingly, the NDI returned with the relapse of renal infiltration 1 year after haplo-SCT. This case suggests that NDI was probably secondary to renal leukemic infiltration.

  13. The cathepsin B inhibitor z-FA-CMK induces cell death in leukemic T cells via oxidative stress.

    PubMed

    Liow, K Y; Chow, Sek C

    2018-01-01

    The cathepsin B inhibitor benzyloxycarbonyl-phenylalanine-alanine-chloromethyl ketone (z-FA-CMK) was recently found to induce apoptosis at low concentrations in Jurkat T cells, while at higher concentrations, the cells die of necrosis. In the present study, we showed that z-FA-CMK readily depletes intracellular glutathione (GSH) with a concomitant increase in reactive oxygen species (ROS) generation. The toxicity of z-FA-CMK in Jurkat T cells was completely abrogated by N-acetylcysteine (NAC), suggesting that the toxicity mediated by z-FA-CMK is due to oxidative stress. We found that L-buthionine sulfoximine (BSO) which depletes intracellular GSH through the inhibition of GSH biosynthesis in Jurkat T cells did not promote ROS increase or induce cell death. However, NAC was still able to block z-FA-CMK toxicity in Jurkat T cells in the presence of BSO, indicating that the protective effect of NAC does not involve GSH biosynthesis. This is further corroborated by the protective effect of the non-metabolically active D-cysteine on z-FA-CMK toxicity. Furthermore, in BSO-treated cells, z-FA-CMK-induced ROS increased which remains unchanged, suggesting that the depletion of GSH and increase in ROS generation mediated by z-FA-CMK may be two separate events. Collectively, our results demonstrated that z-FA-CMK toxicity is mediated by oxidative stress through the increase in ROS generation.

  14. Tumor-specific CD4+ T cells develop cytotoxic activity and eliminate virus-induced tumor cells in the absence of regulatory T cells.

    PubMed

    Akhmetzyanova, Ilseyar; Zelinskyy, Gennadiy; Schimmer, Simone; Brandau, Sven; Altenhoff, Petra; Sparwasser, Tim; Dittmer, Ulf

    2013-02-01

    The important role of tumor-specific cytotoxic CD8(+) T cells is well defined in the immune control of the tumors, but the role of effector CD4(+) T cells is poorly understood. In the current research, we have used a murine retrovirus-induced tumor cell line of C57BL/6 mouse origin, namely FBL-3 cells, as a model to study basic mechanisms of immunological control and escape during tumor formation. This study shows that tumor-specific CD4(+) T cells are able to protect against virus-induced tumor cells. We show here that there is an expansion of tumor-specific CD4(+) T cells producing cytokines and cytotoxic molecule granzyme B (GzmB) in the early phase of tumor growth. Importantly, we demonstrate that in vivo depletion of regulatory T cells (Tregs) and CD8(+) T cells in FBL-3-bearing DEREG transgenic mice augments IL-2 and GzmB production by CD4(+) T cells and increases FV-specific CD4(+) T-cell effector and cytotoxic responses leading to the complete tumor regression. Therefore, the capacity to reject tumor acquired by tumor-reactive CD4(+) T cells largely depends on the direct suppressive activity of Tregs. We suggest that a cytotoxic CD4(+) T-cell immune response may be induced to enhance resistance against oncovirus-associated tumors.

  15. Effect of anti-IL-15 administration on T cell and NK cell homeostasis in rhesus macaques

    PubMed Central

    DeGottardi, Maren Q.; Okoye, Afam A.; Vaidya, Mukta; Talla, Aarthi; Konfe, Audrie L.; Reyes, Matthew D.; Clock, Joseph A.; Duell, Derick M.; Legasse, Alfred W.; Sabnis, Amit; Park, Byung S.; Axthelm, Michael K.; Estes, Jacob D.; Reinmann, Keith A.; Sekaly, Rafick-Pierre; Picker, Louis J.

    2016-01-01

    IL-15 has been implicated as a key regulator of T and NK cell homeostasis in multiple systems; however, its specific role in maintaining peripheral T and NK cell populations relative to other gamma-chain (γc) cytokines has not been fully defined in primates. Here, we address this question by determining the effect of IL-15 inhibition with a rhesusized, anti-IL-15 mAb on T and NK cell dynamics in rhesus macaques. Strikingly, anti-IL-15 treatment resulted in rapid depletion of NK cells, and both CD4+ and CD8+ effector memory T cells (TEM) in blood and tissues, with little to no effect on naïve or central memory T cells. Importantly, whereas depletion of NK cells was nearly complete and maintained as long as anti-IL-15 treatment was given, TEM depletion was countered by the onset of massive TEM proliferation, which almost completely restored circulating TEM numbers. Tissue TEM, however, remained significantly reduced, and most TEM maintained very high turnover throughout anti-IL-15 treatment. In the presence of IL-15 inhibition, TEM became increasingly more sensitive to IL-7 stimulation in vivo, and transcriptional analysis of TEM in IL-15-inhibited monkeys revealed engagement of the JAK/STAT signaling pathway, suggesting alternative γc cytokine signaling may support TEM homeostasis in the absence of IL-15. Thus, IL-15 plays a major role in peripheral maintenance of NK cells and TEM. However, whereas most NK cell populations collapse in the absence of IL-15, TEM can be maintained in the face of IL-15 inhibition by the activity of other homeostatic regulators, most likely IL-7. PMID:27430715

  16. How to select the best available related or unrelated donor of hematopoietic stem cells?

    PubMed

    Tiercy, Jean-Marie

    2016-06-01

    Recognition of HLA incompatibilities by the immune system represents a major barrier to allogeneic hematopoietic stem cell transplantation. HLA genotypically identical sibling donors are, therefore, the gold standard for transplantation purposes, but only 30% patients have such a donor. For the remaining 70% patients alternative sources of stem cells are a matched unrelated adult volunteer donor, a haploidentical donor or a cord blood unit. The definition of 'HLA matching' depends on the level of resolution and on which loci are tested. The development of HLA molecular typing technologies and the availability of more than 27 million donors in the international database has greatly facilitated unrelated donor searches. The gold standard is high resolution typing at the HLA-A, -B, -C, -DRB1, and -DQB1 loci (10/10 match). Single disparities for HLA-A, -B, - C, or -DRB1 are associated with increased risk of post-transplant complications, but less so in patients with advanced disease, and in those undergoing T-cell-depleted allografting. HLA-DQB1 mismatches seem to be better tolerated and some HLA-C, -DRB1 and -DPB1 disparities are potentially less immunogenic. HLA typing by next-generation sequencing methods is likely to change matching algorithms by providing full sequence information on all HLA loci in a single step. In most European populations a 10/10 matched donor can be found for at least 50% of patients and an additional 20-30% patients may have a 9/10 matched donor. Genetic factors that help in identifying donors with less immunogenic mismatches are discussed. Haploidentical donors are increasingly used as an alternative source of stem cells for those patients lacking a matched unrelated donor. Copyright© Ferrata Storti Foundation.

  17. Mucosal-Associated Invariant T Cells in Regenerative Medicine

    PubMed Central

    Wakao, Hiroshi; Sugimoto, Chie; Kimura, Shinzo; Wakao, Rika

    2017-01-01

    Although antibiotics to inhibit bacterial growth and small compounds to interfere with the productive life cycle of human immunodeficiency virus (HIV) have successfully been used to control HIV infection, the recent emergence of the drug-resistant bacteria and viruses poses a serious concern for worldwide public health. Despite intensive scrutiny in developing novel antibiotics and drugs to overcome these problems, there is a dilemma such that once novel antibiotics are launched in markets, sooner or later antibiotic-resistant strains emerge. Thus, it is imperative to develop novel methods to avoid this vicious circle. Here, we discuss the possibility of using induced pluripotent stem cell (iPSC)-derived, innate-like T cells to control infection and potential application of these cells for cancer treatment. Mucosal-associated invariant T (MAIT) cells belong to an emerging family of innate-like T cells that link innate immunity to adaptive immunity. MAIT cells exert effector functions without priming and clonal expansion like innate immune cells and relay the immune response to adaptive immune cells through production of relevant cytokines. With these characteristics, MAIT cells are implicated in a wide range of human diseases such as autoimmune, infectious, and metabolic diseases, and cancer. Circulating MAIT cells are often depleted by these diseases and often remain depleted even after appropriate remedy because MAIT cells are susceptible to activation-induced cell death and poor at proliferation in vivo, which threatens the integrity of the immune system. Because MAIT cells have a pivotal role in human immunity, supplementation of MAIT cells into immunocompromised patients suffering from severe depletion of these cells may help recapitulate or recover immunocompetence. The generation of MAIT cells from human iPSCs has made it possible to procure MAIT cells lost from disease. Such technology creates new avenues for cell therapy and regenerative medicine for

  18. CD4 T cells play important roles in maintaining IL-17-producing γδ T-cell subsets in naive animals.

    PubMed

    Do, Jeong-Su; Visperas, Anabelle; O'Brien, Rebecca L; Min, Booki

    2012-04-01

    A proportional balance between αβ and γδ T-cell subsets in the periphery is exceedingly well maintained by a homeostatic mechanism. However, a cellular mechanism underlying the regulation remains undefined. We recently reported that a subset of developing γδ T cells spontaneously acquires interleukin (IL)-17-producing capacity even within naive animals through a transforming growth factor (TGF)β1-dependent mechanism, thus considered 'innate' IL-17-producing cells. Here, we report that γδ T cells generated within αβ T cell (or CD4 T cell)-deficient environments displayed altered cytokine profiles; particularly, 'innate' IL-17 expression was significantly impaired compared with those in wild-type mice. Impaired IL-17 production in γδ T cells was directly related to CD4 T-cell deficiency, because depletion of CD4 T cells in wild-type mice diminished and adoptive CD4 T-cell transfer into T-cell receptor β-/- mice restored IL-17 expression in γδ T cells. CD4 T cell-mediated IL-17 expression required TGFβ1. Moreover, Th17 but not Th1 or Th2 effector CD4 T cells were highly efficient in enhancing γδ T-cell IL-17 expression. Taken together, our results highlight a novel CD4 T cell-dependent mechanism that shapes the generation of IL-17+ γδ T cells in naive settings.

  19. Graft-versus-leukemia effects of transplantation and donor lymphocytes.

    PubMed

    Kolb, Hans-Jochem

    2008-12-01

    Allogeneic transplantation of hematopoietic cells is an effective treatment of leukemia, even in advanced stages. Allogeneic lymphocytes produce a strong graft-versus-leukemia (GVL) effect, but the beneficial effect is limited by graft-versus-host disease (GVHD). Depletion of T cells abrogates GVHD and GVL effects. Delayed transfusion of donor lymphocytes into chimeras after T cell-depleted stem cell transplantation produces a GVL effect without necessarily producing GVHD. Chimerism and tolerance provide a platform for immunotherapy using donor lymphocytes. The allogeneic GVL effects vary from one disease to another, the stage of the disease, donor histocompatibility, the degree of chimerism, and additional treatment. Immunosuppressive therapy before donor lymphocyte transfusions may augment the effect as well as concomitant cytokine treatment. Possible target antigens are histocompatibility antigens and tumor-associated antigens. Immune escape of tumor cells and changes in the reactivity of T cells are to be considered. Durable responses may be the result of the elimination of leukemia stem cells or the establishment of a durable immune control on their progeny. Recently, we have learned from adoptive immunotherapy of viral diseases and HLA-haploidentical stem cell transplantation that T-cell memory may be essential for the effective treatment of leukemia and other malignancies.

  20. Massive infection and loss of CD4+ T cells occurs in the intestinal tract of neonatal rhesus macaques in acute SIV infection

    PubMed Central

    Wang, Xiaolei; Rasmussen, Terri; Pahar, Bapi; Poonia, Bhawna; Alvarez, Xavier; Lackner, Andrew A.; Veazey, Ronald S.

    2007-01-01

    Rapid, profound, and selective depletion of memory CD4+ T cells has now been confirmed to occur in simian immunodeficiency virus (SIV)–infected adult macaques and human immunodeficiency virus (HIV)–infected humans. Within days of infection, marked depletion of memory CD4+ T cells occurs primarily in mucosal tissues, the major reservoir for memory CD4+ T cells in adults. However, HIV infection in neonates often results in higher viral loads and rapid disease progression, despite the paucity of memory CD4+ T cells in the peripheral blood. Here, we examined the immunophenotype of CD4+ T cells in normal and SIV-infected neonatal macaques to determine the distribution of naive and memory T-cell subsets in tissues. We demonstrate that, similar to adults, neonates have abundant memory CD4+ T cells in the intestinal tract and spleen and that these are selectively infected and depleted in primary SIV infection. Within 12 days of SIV infection, activated (CD69+), central memory (CD95+CD28+) CD4+ T cells are marked and persistently depleted in the intestine and other tissues of neonates compared with controls. The results in dicate that “activated” central memory CD4+ T cells are the major target for early SIV infection and CD4+ T cell depletion in neonatal macaques. PMID:17047153

  1. Fatal neonatal-onset mitochondrial respiratory chain disease with T cell immunodeficiency.

    PubMed

    Reichenbach, Janine; Schubert, Ralf; Horvàth, Rita; Petersen, Jens; Fütterer, Nancy; Malle, Elisabeth; Stumpf, Andreas; Gebhardt, Boris R; Koehl, Ulrike; Schraven, Burkhart; Zielen, Stefan

    2006-09-01

    We present the clinical and laboratory features of a boy with a new syndrome of mitochondrial depletion syndrome and T cell immunodeficiency. The child suffered from severe recurrent infectious diseases, anemia, and thrombocytopenia. Clinically, he presented with severe psychomotor retardation, axial hypotonia, and a disturbed pain perception leading to debilitating biting of the thumb, lower lip, and tongue. Brain imaging showed hypoplasia of corpus callosum and an impaired myelinization of the temporo-occipital region with consecutive supratentorial hydrocephalus. Histologic examination of a skeletal muscle biopsy was normal. Biochemical investigation showed combined deficiency of respiratory chain complexes II+III and IV. MtDNA depletion was found by real-time PCR. No pathogenic mutations were identified in the TK2, SUCLA2, DGUOK, and ECGF1 genes. A heterozygous missense mutation was found in POLG1. The pathogenic relevance of this mutation is unclear. Interestingly, a lack of CD8(+) T lymphocytes as well as NK cells was also observed. The percentage of CD45RO-expressing cells was decreased in activated CD8(+) T lymphocytes. Activation of T lymphocytes via IL-2 was diminished. The occurrence of the immunologic deficiency in our patient with mtDNA depletion is a rare finding, implying that cells of the immune system might also be affected by mitochondrial disease.

  2. Breaking tolerance to self, circulating natural killer cells expressing inhibitory KIR for non-self HLA exhibit effector function after T cell-depleted allogeneic hematopoietic cell transplantation.

    PubMed

    Yu, Junli; Venstrom, Jeffrey M; Liu, Xiao-Rong; Pring, James; Hasan, Reenat S; O'Reilly, Richard J; Hsu, Katharine C

    2009-04-16

    Alloreactive natural killer (NK) cells are an important influence on hematopoietic stem cell transplantation (HSCT) outcome. In HLA-mismatched HSCT, alloreactivity occurs when licensed donor NK cells expressing inhibitory killer Ig-like receptors (KIR) for donor MHC class I ligands recognize the lack of the class I ligands in the mismatched recipient ("missing self"). Studies in HLA-matched HSCT, however, have also demonstrated improved outcome in patients lacking class I ligands for donor inhibitory KIR ("missing ligand"), indicating that classically nonlicensed donor NK cells expressing KIR for non-self MHC class I ligands may exhibit functional competence in HSCT. We examined NK function in 16 recipients of T cell-depleted allografts from HLA-identical or KIR-ligand matched donors after myeloablative therapy. After HSCT, nonlicensed NK cells expressing inhibitory KIR for non-self class I exhibit robust intracellular IFN-gamma and cytotoxic response to target cells lacking cognate ligand, gradually becoming tolerized to self by day 100. These findings could not be correlated with cytokine environment or phenotypic markers of NK development, nor could they be attributed to non-KIR receptors such as CD94/NKG2A. These findings confirm that NK alloreactivity can occur in HLA-matched HSCT, where tolerance to self is either acquired by the stem cell-derived NK cell after exiting the bone marrow or where tolerance to self can be temporarily overcome.

  3. Recipient/donor HLA and CMV matching in recipients of T-cell-depleted unrelated donor haematopoietic cell transplants.

    PubMed

    Shaw, B E; Mayor, N P; Szydlo, R M; Bultitude, W P; Anthias, C; Kirkland, K; Perry, J; Clark, A; Mackinnon, S; Marks, D I; Pagliuca, A; Potter, M N; Russell, N H; Thomson, K; Madrigal, J A; Marsh, S G E

    2017-05-01

    Improving haematopoietic cell transplantation outcomes by selection of an HLA-matched unrelated donor is best practice; however, donor selection by secondary characteristics is controversial. We studied 1271 recipients with haematological malignancies who underwent T-cell-depleted allografts and had complete data on HLA-matching status for six loci (HLA-A, -B, -C, -DRB1, -DQB1, -DPB1) and clinical outcome data. Five-year overall survival was 40.6%. HLA mismatching (at HLA-A, -B, -C, -DRB1, -DQB1) relative risk (RR) 1.22, 95% confidence interval (CI) 1.2-1.5, P=0.033 for 1 mismatch and RR 1.46, 95% CI 1.1-1.9, P=0.009 for >1 mismatch) and CMV mismatching (RR 1.37, 95% CI 1.2-1.6, P<0.001) were significantly associated with inferior survival. Donors aged <30 years showed a trend towards better survival. The multivariate model for mortality, combining CMV and HLA-match status, found an RR of 1.36 (95% CI 1.1-1.7, P=0.003) for HLA matched/CMV mismatched, an RR of 1.22 (95% CI 0.99-1.5, P=0.062) for HLA mismatched/CMV matched and an RR of 1.81 (95% CI 1.4-2.3, P=<0.001) for HLA/ CMV mismatched, compared with the HLA/CMV-matched recipients. These data suggest that HLA and CMV matching status should be considered when selecting unrelated donors and that CMV matching may abrogate the effect of an HLA mismatch.

  4. CD4+CD25+ T-Cells Control Autoimmunity in the Absence of B-Cells

    PubMed Central

    Mariño, Eliana; Villanueva, Jeanette; Walters, Stacey; Liuwantara, David; Mackay, Fabienne; Grey, Shane T.

    2009-01-01

    OBJECTIVE Tumor necrosis factor ligand family members B-cell–activating factor (BAFF) and a proliferation-inducing ligand (APRIL) can exert powerful effects on B-cell activation and development, type 1 T-helper cell (Th1) immune responses, and autoimmunity. We examined the effect of blocking BAFF and APRIL on the development of autoimmune diabetes. RESEARCH DESIGN AND METHODS Female NOD mice were administered B-cell maturation antigen (BCMA)-Fc from 9 to 15 weeks of age. Diabetes incidence, islet pathology, and T- and B-cell populations were examined. RESULTS BCMA-Fc treatment reduced the severity of insulitis and prevented diabetes development in NOD mice. BCMA-Fc–treated mice showed reduced follicular, marginal-zone, and T2MZ B-cells. B-cell reduction was accompanied by decreased frequencies of pathogenic CD4+CD40+ T-cells and reduced Th1 cytokines IL-7, IL-15, and IL-17. Thus, T-cell activation was blunted with reduced B-cells. However, BCMA-Fc–treated mice still harbored detectable diabetogenic T-cells, suggesting that regulatory mechanisms contributed to diabetes prevention. Indeed, BCMA-Fc–treated mice accumulated increased CD4+CD25+ regulatory T-cells (Tregs) with age. CD4+CD25+ cells were essential for maintaining euglycemia because their depletion abrogated BCMA-Fc–mediated protection. BCMA-Fc did not directly affect Treg homeostasis given that CD4+CD25+Foxp3+ T-cells did not express TACI or BR3 receptors and that CD4+CD25+Foxp3+ T-cell frequencies were equivalent in wild-type, BAFF−/−, TACI−/−, BCMA−/−, and BR3−/− mice. Rather, B-cell depletion resulted in CD4+CD25+ T-cell–mediated protection from diabetes because anti-CD25 monoclonal antibody treatment precipitated diabetes in both diabetes-resistant NOD.μMT−/− and BCMA-Fc–treated mice. CONCLUSIONS BAFF/APRIL blockade prevents diabetes. BCMA-Fc reduces B-cells, subsequently blunting autoimmune activity and allowing endogenous regulatory mechanisms to preserve a

  5. Autoimmune oophoritis in thymectomized mice: T cell requirement in adoptive cell transfer.

    PubMed Central

    Taguchi, O; Nishizuka, Y

    1980-01-01

    Experimental autoimmune oophoritis characterized by rapid loss of oocytes with infiltration of lymphocytes and circulating anti-oocyte antibodies could be induced in (C57Bl/6Cr x A/JCr)F1 mice after thymectomy (Tx) at a critical age of 3 days (Tx-3) but not 0. or 7 days after birth without any sensitization. The lesion of the ovary was passively transferred into neonatal, but not adult, mice 7 days after intraperitoneal (i.p.) injection of spleen cells (10(7)) obtained from syngeneic donors with oophoritis. In contrast, the lesion was never evoked in the recipient ovaries when spleen cells were prepared from Tx-3 mice ovariectomized at day 0. The spleen cells prepared from Tx-3 donors, depleted of T cells by incubation with anti-Thy 1.2 antiserum plus guinea-pig complement (GPC), showed no transfer capacity. However, the spleen cells prepared from the same donors, depleted of B cells with anti-Ig antiserum plus GPC, still kept the capacity to induce oophoritis. The results indicate the presence of autoreactive T cells against ovarian tissues in Tx-3 mice which are capable of inducing oophoritis. Images Fig. 1 Fig. 2 Fig. 3 PMID:6970639

  6. Identification of Regulatory T Cells in Tolerated Allografts

    PubMed Central

    Graca, Luis; Cobbold, Stephen P.; Waldmann, Herman

    2002-01-01

    Induction of transplantation tolerance with certain therapeutic nondepleting monoclonal antibodies can lead to a robust state of peripheral “dominant” tolerance. Regulatory CD4+ T cells, which mediate this form of “dominant” tolerance, can be isolated from spleens of tolerant animals. To determine whether there were any extra-lymphoid sites that might harbor regulatory T cells we sought their presence in tolerated skin allografts and in normal skin. When tolerated skin grafts are retransplanted onto T cell–depleted hosts, graft-infiltrating T cells exit the graft and recolonize the new host. These colonizing T cells can be shown to contain members with regulatory function, as they can prevent nontolerant lymphocytes from rejecting fresh skin allografts, without hindrance of rejection of third party skin. Our results suggest that T cell suppression of graft rejection is an active process that operates beyond secondary lymphoid tissue, and involves the persistent presence of regulatory T cells at the site of the tolerated transplant. PMID:12070291

  7. A Murine Herpesvirus Closely Related to Ubiquitous Human Herpesviruses Causes T-Cell Depletion

    PubMed Central

    Zhao, Guoyan; Penna, Vinay R.; Park, Eugene; Lauron, Elvin J.; Harvey, Ian B.; Beatty, Wandy L.; Plougastel-Douglas, Beatrice; Poursine-Laurent, Jennifer; Fremont, Daved H.; Wang, David

    2017-01-01

    and clinical ramifications of roseolovirus infection in humans have been hypothesized, but studies showing definitive causative relationships between infection and disease susceptibility are lacking. Here we show that MRV infects the thymus and causes T-cell depletion, suggesting that other roseoloviruses may have similar properties. PMID:28179532

  8. A Murine Herpesvirus Closely Related to Ubiquitous Human Herpesviruses Causes T-Cell Depletion.

    PubMed

    Patel, Swapneel J; Zhao, Guoyan; Penna, Vinay R; Park, Eugene; Lauron, Elvin J; Harvey, Ian B; Beatty, Wandy L; Plougastel-Douglas, Beatrice; Poursine-Laurent, Jennifer; Fremont, Daved H; Wang, David; Yokoyama, Wayne M

    2017-05-01

    clinical ramifications of roseolovirus infection in humans have been hypothesized, but studies showing definitive causative relationships between infection and disease susceptibility are lacking. Here we show that MRV infects the thymus and causes T-cell depletion, suggesting that other roseoloviruses may have similar properties. Copyright © 2017 American Society for Microbiology.

  9. Antithymocyte globulins in renal transplantation-from lymphocyte depletion to lymphocyte activation: The doubled-edged sword.

    PubMed

    Bamoulid, Jamal; Crépin, Thomas; Courivaud, Cécile; Rebibou, Jean-Michel; Saas, Philippe; Ducloux, Didier

    2017-07-01

    Compelling data suggest that lymphocyte depletion following T cell depleting therapy may induce prolonged CD4 T cell lymphopenia and trigger lymphocyte activation in some patients. These profound and non-reversible immune changes in T cell pool subsets are the consequence of both impaired thymic renewal and peripheral homeostatic proliferation. Chronic viral challenges by CMV play a major role in these immune alterations. Even when the consequences of CD4 T cell lymphopenia have been now well described, recent studies shed new light on the clinical consequences of immune activation. In this review, we will first focus on the mechanisms involved in T cell pool reconstitution after T cell depletion and further consider the clinical consequences of ATG-induced T cell activation and senescence in renal transplant recipients. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Phosphoproteomics Reveals Regulatory T Cell-Mediated DEF6 Dephosphorylation That Affects Cytokine Expression in Human Conventional T Cells

    PubMed Central

    Joshi, Rubin N.; Binai, Nadine A.; Marabita, Francesco; Sui, Zhenhua; Altman, Amnon; Heck, Albert J. R.; Tegnér, Jesper; Schmidt, Angelika

    2017-01-01

    Regulatory T cells (Tregs) control key events of immune tolerance, primarily by suppression of effector T cells. We previously revealed that Tregs rapidly suppress T cell receptor (TCR)-induced calcium store depletion in conventional CD4+CD25− T cells (Tcons) independently of IP3 levels, consequently inhibiting NFAT signaling and effector cytokine expression. Here, we study Treg suppression mechanisms through unbiased phosphoproteomics of primary human Tcons upon TCR stimulation and Treg-mediated suppression, respectively. Tregs induced a state of overall decreased phosphorylation as opposed to TCR stimulation. We discovered novel phosphosites (T595_S597) in the DEF6 (SLAT) protein that were phosphorylated upon TCR stimulation and conversely dephosphorylated upon coculture with Tregs. Mutation of these DEF6 phosphosites abrogated interaction of DEF6 with the IP3 receptor and affected NFAT activation and cytokine transcription in primary Tcons. This novel mechanism and phosphoproteomics data resource may aid in modifying sensitivity of Tcons to Treg-mediated suppression in autoimmune disease or cancer. PMID:28993769

  11. Reciprocal relationship of T regulatory cells and monocytic myeloid-derived suppressor cells in LP-BM5 murine retrovirus-induced immunodeficiency.

    PubMed

    O'Connor, Megan A; Vella, Jennifer L; Green, William R

    2016-02-01

    Immunomodulatory cellular subsets, including myeloid-derived suppressor cells (MDSCs) and T regulatory cells (Tregs), contribute to the immunosuppressive tumour microenvironment and are targets of immunotherapy, but their role in retroviral-associated immunosuppression is less well understood. Due to known crosstalk between Tregs and MDSCs in the tumour microenvironment, and also their hypothesized involvement during human immunodeficiency virus/simian immunodeficiency virus infection, studying the interplay between these immune cells during LP-BM5 retrovirus-induced murine AIDS is of interest. IL-10-producing FoxP3+ Tregs expanded after LP-BM5 infection. Following in vivo adoptive transfer of natural Treg (nTreg)-depleted CD4+T-cells, and subsequent LP-BM5 retroviral infection, enriched monocytic MDSCs (M-MDSCs) from these nTreg-depleted mice displayed altered phenotypic subsets. In addition, M-MDSCs from LP-BM5-infected nTreg-depleted mice exhibited increased suppression of T-cell, but not B-cell, responses, compared with M-MDSCs derived from non-depleted LP-BM5-infected controls. Additionally, LP-BM5-induced M-MDSCs modulated the production of IL-10 by FoxP3+ Tregs in vitro. These collective data highlight in vitro and for the first time, to the best of our knowledge, in vivo reciprocal modulation between retroviral-induced M-MDSCs and Tregs, and may provide insight into the immunotherapeutic targeting of such regulatory cells during retroviral infection.

  12. Long-Term Tolerance Towards Haploidentical Vascularized Composite Allograft Transplantation in a Canine Model Using Bone Marrow or Mobilized Stem Cells

    PubMed Central

    Chang, Jeff; Graves, Scott S.; Butts-Miwongtum, Tiffany; Sale, George E.; Storb, Rainer; Mathes, David W.

    2017-01-01

    Background The development of safe and reliable protocols for the transplantation of the face and hands may be accomplished with animal modeling of transplantation of vascularized composite allografts (VCA). Previously, we demonstrated that tolerance to a VCA could be achieved after canine recipients were simultaneously given marrow from a dog leukocyte antigen (DLA) identical donor. In the present study, we extend those findings across a DLA mismatched barrier. Methods Eight Recipient dogs received total body irradiation (4.5 cGy), hematopoietic cell transplantation (HCT), either marrow (n=4) or granulocyte-colony stimulating factor (G-CSF) mobilized peripheral blood stem cells (n=4), and a VCA transplant from the HCT donor. Post grafting immunosuppression consisted of mycophenolate mofetil (28 days) and cyclosporine (35 days). Results In 4 dogs receiving bone marrow, 1 accepted both its marrow transplant and demonstrated long-term tolerance to the donor VCA (>52 weeks). Three dogs rejected both their marrow transplants and VCA at 5–7 weeks posttransplant. Dogs receiving mobilized stem cells all accepted their stem cell transplant and became tolerant to the VCA. However, 3 dogs developed graft-versus-host disease (GVHD) while 1 dog rejected its stem cell graft by week 15 but exhibited long-term tolerance towards its VCA (>90 weeks). Conclusion The data suggest that simultaneous transplantation of mobilized stem cells and a VCA is feasible and leads to tolerance towards the VCA in a haploidentical setting. However, there is a higher rate of donor stem cell engraftment compared to marrow HCT and an increase in the incidence of GVHD. PMID:27861292

  13. Dramatic increase in naive T cell turnover is linked to loss of naive T cells from old primates.

    PubMed

    Cicin-Sain, Luka; Messaoudi, Ilhem; Park, Byung; Currier, Noreen; Planer, Shannon; Fischer, Miranda; Tackitt, Shane; Nikolich-Zugich, Dragana; Legasse, Alfred; Axthelm, Michael K; Picker, Louis J; Mori, Motomi; Nikolich-Zugich, Janko

    2007-12-11

    The loss of naïve T cells is a hallmark of immune aging. Although thymic involution is a primary driver of this naïve T cell loss, less is known about the contribution of other mechanisms to the depletion of naïve T cells in aging primates. We examined the role of homeostatic cycling and proliferative expansion in different T cell subsets of aging rhesus macaques (RM). BrdU incorporation and the expression of the G(1)-M marker Ki-67 were elevated in peripheral naïve CD4 and even more markedly in the naïve CD8 T cells of old, but not young adult, RM. Proliferating naïve cells did not accumulate in old animals. Rather, the relative size of the naïve CD8 T cell compartment correlated inversely to its proliferation rate. Likewise, T cell receptor diversity decreased in individuals with elevated naïve CD8 T cell proliferation. This apparent contradiction was explained by a significant increase in turnover concomitant with the naïve pool loss. The turnover increased exponentially when the naïve CD8 T cell pool decreased below 4% of total blood CD8 cells. These results link the shrinking naïve T cell pool with a dramatic increase in homeostatic turnover, which has the potential to exacerbate the progressive exhaustion of the naïve pool and constrict the T cell repertoire. Thus, homeostatic T cell proliferation exhibits temporal antagonistic pleiotropy, being beneficial to T cell maintenance in adulthood but detrimental to the long-term T cell maintenance in aging individuals.

  14. ARMS depletion facilitates UV irradiation induced apoptotic cell death in melanoma.

    PubMed

    Liao, Yi-Hua; Hsu, Su-Ming; Huang, Pei-Hsin

    2007-12-15

    Tumor cells often aberrantly reexpress molecules that mediate proper embryonic development for advantageous growth or survival. Here, we report that ankyrin repeat-rich membrane spanning (ARMS), a transmembrane protein abundant in the developing and adult neural tissues, is overexpressed in melanoma, a tumor ontogenetically originating from neural crest. Immunohistochemical study of 79 melanocytic lesions showed significantly increased expression of ARMS in primary malignant melanomas (92.9%) and metastatic melanoma (60.0%) in comparison with benign nevocellular nevi (26.7%). To investigate the role of ARMS in melanoma formation, murine B16F0 melanoma cells with stable knockdown of ARMS were established by RNA interference. Down-regulation of ARMS resulted in significant inhibition of anchorage-independent growth in soft agar and restrictive growth of melanoma in severe combined immunodeficient mice. Importantly, depletion of ARMS facilitated UVB-induced apoptosis in melanoma cells through inactivation of mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK)/ERK. Addition of MEK inhibitor PD98059 further sensitized ARMS-depleted melanoma cells to UVB-induced apoptosis, whereas constitutively active MEK rescued ARMS-depleted cells from apoptosis. We further showed that BRAF, a downstream signaling molecule of ARMS in ERK pathway, is not mutated as a constitutively active form in acral lentiginous melanoma; in contrast, BRAF(T1799A) mutation, which leads to constitutive activation of ERK signaling, was detected in 57.1% of superficial spreading melanoma. Our study suggests that overexpression of ARMS per se serves as one mechanism to promote melanoma formation by preventing stress-induced apoptotic death mediated by the MEK/ERK signaling pathway, especially in acral lentiginous melanoma, most of which does not harbor BRAF mutation.

  15. Inflammation Causes Resistance to Anti-CD20-Mediated B Cell Depletion.

    PubMed

    Laws, L H; Parker, C E; Cherala, G; Koguchi, Y; Waisman, A; Slifka, M K; Oberbarnscheidt, M H; Obhrai, J S; Yeung, M Y; Riella, L V

    2016-11-01

    B cells play a central role in antibody-mediated rejection and certain autoimmune diseases. However, B cell-targeted therapy such as anti-CD20 B cell-depleting antibody (aCD20) has yielded mixed results in improving outcomes. In this study, we investigated whether an accelerated B cell reconstitution leading to aCD20 depletion resistance could account for these discrepancies. Using a transplantation model, we found that antigen-independent inflammation, likely through toll-like receptor (TLR) signaling, was sufficient to mitigate B cell depletion. Secondary lymphoid organs had a quicker recovery of B cells when compared to peripheral blood. Inflammation altered the pharmacokinetics (PK) and pharmacodynamics (PD) of aCD20 therapy by shortening drug half-life and accelerating the reconstitution of the peripheral B cell pool by bone marrow-derived B cell precursors. IVIG (intravenous immunoglobulin) coadministration also shortened aCD20 drug half-life and led to accelerated B cell recovery. Repeated aCD20 dosing restored B cell depletion and delayed allograft rejection, especially B cell-dependent, antibody-independent allograft rejection. These data demonstrate the importance of further clinical studies of the PK/PD of monoclonal antibody treatment in inflammatory conditions. The data also highlight the disconnect between B cell depletion on peripheral blood compared to secondary lymphoid organs, the deleterious effect of IVIG when given with aCD20 and the relevance of redosing of aCD20 for effective B cell depletion in alloimmunity. © Copyright 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.

  16. Autoantigen-specific B-cell depletion overcomes failed immune tolerance in type 1 diabetes.

    PubMed

    Henry, Rachel A; Kendall, Peggy L; Thomas, James W

    2012-08-01

    Eliminating autoantigen-specific B cells is an attractive alternative to global B-cell depletion for autoimmune disease treatment. To identify the potential for targeting a key autoimmune B-cell specificity in type 1 diabetes, insulin-binding B cells were tracked within a polyclonal repertoire using heavy chain B-cell receptor (BCR) transgenic (VH125Tg) mice. Insulin-specific B cells are rare in the periphery of nonautoimmune VH125Tg/C57BL/6 mice and WT/NOD autoimmune mice, whereas they clearly populate 1% of mature B-cell subsets in VH125Tg/NOD mice. Autoantigen upregulates CD86 in anti-insulin B cells, suggesting they are competent to interact with T cells. Endogenous insulin occupies anti-insulin BCR beginning with antigen commitment in bone marrow parenchyma, as identified by a second anti-insulin monoclonal antibody. Administration of this monoclonal antibody selectively eliminates insulin-reactive B cells in vivo and prevents disease in WT/NOD mice. Unexpectedly, developing B cells are less amenable to depletion, despite increased BCR sensitivity. These findings exemplify how a critical type 1 diabetes B-cell specificity escapes immune tolerance checkpoints. Disease liability is corrected by eliminating this B-cell specificity, providing proof of concept for a novel therapeutic approach for autoimmune disease.

  17. Major role for CD8 T cells in the protection against Toxoplasma gondii following dendritic cell vaccination.

    PubMed

    Guiton, R; Zagani, R; Dimier-Poisson, I

    2009-10-01

    Toxoplasma gondii is the causative agent of toxoplasmosis, a worldwide zoonosis for which an effective vaccine is needed. Vaccination with pulsed dendritic cells is very efficient but their use in a vaccination protocol is unconceivable. Nevertheless, unravelling the induced effector mechanisms is crucial to design new vaccine strategies. We vaccinated CBA/J mice with parasite extract-pulsed dendritic cells, challenged them with T. gondii cysts and carried out in vivo depletion of CD4(+) or CD8(+) T lymphocytes to study the subsequent cellular immune response and protective mechanisms. CD4(+) lymphocytes were poorly implicated either in spleen and mesenteric lymph node (MLN) cytokine secretion or in mice protection. By contrast, the increasing number of intracerebral cysts and depletion of CD8(+) cells were strongly correlated, revealing a prominent role for CD8(+) lymphocytes in the protection of mice. Splenic CD8(+) lymphocytes induce a strong Th1 response controlled by a Th2 response whereas CD8(+) cells from MLNs inhibit both Th1 and Th2 responses. CD8(+) cells are the main effectors following dendritic cell vaccination and Toxoplasma infection while CD4(+) T cells only play a minor role. This contrasts with T. gondii infection which elicits the generation of CD4(+) and CD8(+) T cells that provide protective immunity.

  18. Fluoxetine suppresses calcium signaling in human T lymphocytes through depletion of intracellular calcium stores.

    PubMed

    Gobin, V; De Bock, M; Broeckx, B J G; Kiselinova, M; De Spiegelaere, W; Vandekerckhove, L; Van Steendam, K; Leybaert, L; Deforce, D

    2015-09-01

    Selective serotonin reuptake inhibitors, such as fluoxetine, have recently been shown to exert anti-inflammatory and immunosuppressive effects. Although the effects on cytokine secretion, proliferation and viability of T lymphocytes have been extensively characterized, little is known about the mechanism behind these effects. It is well known that Ca(2+) signaling is an important step in the signaling transduction pathway following T cell receptor activation. Therefore, we investigated if fluoxetine interferes with Ca(2+) signaling in Jurkat T lymphocytes. Fluoxetine was found to suppress Ca(2+) signaling in response to T cell receptor activation. Moreover, fluoxetine was found to deplete intracellular Ca(2+) stores, thereby leaving less Ca(2+) available for release upon IP3- and ryanodine-receptor activation. The Ca(2+)-modifying effects of fluoxetine are not related to its capability to block the serotonin transporter, as even a large excess of 5HT did not abolish the effects. In conclusion, these data show that fluoxetine decreases IP3- and ryanodine-receptor mediated Ca(2+) release in Jurkat T lymphocytes, an effect likely to be at the basis of the observed immunosuppression. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Chemotherapy-induced B-cell depletion in hepatoblastoma patients undergoing ABO-incompatible living donor liver transplantation.

    PubMed

    Kanazawa, Hiroyuki; Fukuda, Akinari; Mali, Vidyadhar Padmakar; Rahayatri, Tri Hening; Hirata, Yoshihiro; Sasaki, Kengo; Uchida, Hajime; Shigeta, Takanobu; Sakamoto, Seisuke; Matsumoto, Kimikazu; Kasahara, Mureo

    2016-05-01

    LT from ABO-I donors requires preconditioning regimens to prevent postoperative catastrophic AMR. NAC for HBL is known to cause myelosuppression leading to a reduction in the number and function of lymphocytes. We investigated this chemotherapy-induced myelosuppression in HBL patients listed for LT from ABO-I donors with reference to the kinetics of B, T cells, and anti-ABO blood type isoagglutinin titers. Between 2005 and 2015, of the 319 patients who underwent LDLT at our institute, 12 were indicated for unresectable HBL. Three patients with unresectable HBL who underwent LDLT from ABO-I donors are included in this study. Immunosuppression consisted of a standard regime of tacrolimus and low-dose steroids as in ABO compatible/identical LDLT. No additional preoperative therapies for B-cell depletion were used. Absolute lymphocyte counts, lymphocyte subsets (including CD20+ B cells, CD3+CD4+ T cells and CD3+CD8+ T cells), and anti-ABO blood type isoagglutinin titers were measured before LDLT and postoperatively. The median age at diagnosis was 19 months (range, 3-31 months). The median follow-up was seven months (range, 6-15 months). The median interval from the last NAC to LDLT was 33 days (range, 25-52 days). The median interval from LDLT to adjuvant chemotherapy was 28 days (range, 22-36 days). The counts of CD20+ B cells before LDLT were depleted to median 5 cells/mm(3) (range, 0-6 cells/mm(3)). There was a transient rebound in the CD20+ B cell counts on day seven (maximum of 82 cells/mm(3)) followed by a decline starting at 14 days after LDLT that was sustained for the duration of adjuvant chemotherapy. Anti-ABO blood type isoagglutinin titers were lowered to between 1:1 and 1:16 before LDLT and remained low for the duration of follow-up in this study. All of the three patients remained in good health without either acute cellular or AMR after LDLT. The B-cell depletion that occurs after cisplatin-based chemotherapy for HBL may help accomplish safe ABO-I LDLT

  20. Serum BAFF and APRIL Levels, T-Lymphocyte Subsets, and Immunoglobulins after B-Cell Depletion Using the Monoclonal Anti-CD20 Antibody Rituximab in Myalgic Encephalopathy/Chronic Fatigue Syndrome.

    PubMed

    Lunde, Sigrid; Kristoffersen, Einar K; Sapkota, Dipak; Risa, Kristin; Dahl, Olav; Bruland, Ove; Mella, Olav; Fluge, Øystein

    2016-01-01

    Myalgic Encephalopathy/Chronic Fatigue Syndrome (ME/CFS) is a disease of unknown etiology. We have previously suggested clinical benefit from B-cell depletion using the monoclonal anti-CD20 antibody rituximab in a randomized and placebo-controlled study. Prolonged responses were then demonstrated in an open-label phase-II study with maintenance rituximab treatment. Using blood samples from patients in the previous two clinical trials, we investigated quantitative changes in T-lymphocyte subsets, in immunoglobulins, and in serum levels of two B-cell regulating cytokines during follow-up. B-lymphocyte activating factor of the tumor necrosis family (BAFF) in baseline serum samples was elevated in 70 ME/CFS patients as compared to 56 healthy controls (p = 0.011). There were no significant differences in baseline serum BAFF levels between patients with mild, moderate, or severe ME/CFS, or between responders and non-responders to rituximab. A proliferation-inducing ligand (APRIL) serum levels were not significantly different in ME/CFS patients compared to healthy controls at baseline, and no changes in serum levels were seen during follow-up. Immunophenotyping of peripheral blood T-lymphocyte subsets and T-cell activation markers at multiple time points during follow-up showed no significant differences over time, between rituximab and placebo groups, or between responders and non-responders to rituximab. Baseline serum IgG levels were significantly lower in patients with subsequent response after rituximab therapy compared to non-responders (p = 0.03). In the maintenance study, slight but significant reductions in mean serum immunoglobulin levels were observed at 24 months compared to baseline; IgG 10.6-9.5 g/L, IgA 1.8-1.5 g/L, and IgM 0.97-0.70 g/L. Although no functional assays were performed, the lack of significant associations of T- and NK-cell subset numbers with B-cell depletion, as well as the lack of associations to clinical responses, suggest that B-cell

  1. Impact of Multi-Targeted Antiretroviral Treatment on Gut T Cell Depletion and HIV Reservoir Seeding during Acute HIV Infection

    PubMed Central

    Ananworanich, Jintanat; Schuetz, Alexandra; Vandergeeten, Claire; Sereti, Irini; de Souza, Mark; Rerknimitr, Rungsun; Dewar, Robin; Marovich, Mary; van Griensven, Frits; Sekaly, Rafick; Pinyakorn, Suteeraporn; Phanuphak, Nittaya; Trichavaroj, Rapee; Rutvisuttinunt, Wiriya; Chomchey, Nitiya; Paris, Robert; Peel, Sheila; Valcour, Victor; Maldarelli, Frank; Chomont, Nicolas; Michael, Nelson; Phanuphak, Praphan; Kim, Jerome H.

    2012-01-01

    Background Limited knowledge exists on early HIV events that may inform preventive and therapeutic strategies. This study aims to characterize the earliest immunologic and virologic HIV events following infection and investigates the usage of a novel therapeutic strategy. Methods and Findings We prospectively screened 24,430 subjects in Bangkok and identified 40 AHI individuals. Thirty Thais were enrolled (8 Fiebig I, 5 Fiebig II, 15 Fiebig III, 2 Fiebig IV) of whom 15 completed 24 weeks of megaHAART (tenofovir/emtricitabine/efavirenz/raltegravir/maraviroc). Sigmoid biopsies were completed in 24/30 at baseline and 13/15 at week 24. At baseline, the median age was 29 years and 83% were MSM. Most were symptomatic (87%), and were infected with R5-tropic (77%) CRF01_AE (70%). Median CD4 was 406 cells/mm3. HIV RNA was 5.5 log10 copies/ml. Median total blood HIV DNA was higher in Fiebig III (550 copy/106 PBMC) vs. Fiebig I (8 copy/106 PBMC) (p = 0.01) while the median %CD4+CCR5+ gut T cells was lower in Fiebig III (19%) vs. Fiebig I (59%) (p = 0.0008). After 24 weeks of megaHAART, HIV RNA levels of <50 copies were achieved in 14/15 in blood and 13/13 in gut. Total blood HIV DNA at week 0 predicted reservoir size at week 24 (p<0.001). Total HIV DNA declined significantly and was undetectable in 3 of 15 in blood and 3 of 7 in gut. Frequency of CD4+CCR5+ gut T cells increased from 41% at baseline to 64% at week 24 (p>0.050); subjects with less than 40% at baseline had a significant increase in CD4+CCR5+ T cells from baseline to week 24 (14% vs. 71%, p = 0.02). Conclusions Gut T cell depletion and HIV reservoir seeding increases with progression of AHI. MegaHAART was associated with immune restoration and reduced reservoir size. Our findings could inform research on strategies to achieve HIV drug-free remission. PMID:22479485

  2. T cells are not required for pathogenesis in the Syrian hamster model of hantavirus pulmonary syndrome.

    PubMed

    Hammerbeck, Christopher D; Hooper, Jay W

    2011-10-01

    Andes virus (ANDV) is associated with a lethal vascular leak syndrome in humans termed hantavirus pulmonary syndrome (HPS). In hamsters, ANDV causes a respiratory distress syndrome closely resembling human HPS. The mechanism for the massive vascular leakage associated with HPS is poorly understood; however, T cell immunopathology has been implicated on the basis of circumstantial and corollary evidence. Here, we show that following ANDV challenge, hamster T cell activation corresponds with the onset of disease. However, treatment with cyclophosphamide or specific T cell depletion does not impact the course of disease or alter the number of surviving animals, despite significant reductions in T cell number. These data demonstrate, for the first time, that T cells are not required for hantavirus pathogenesis in the hamster model of human HPS. Depletion of T cells from Syrian hamsters did not significantly influence early events in disease progression. Moreover, these data argue for a mechanism of hantavirus-induced vascular permeability that does not involve T cell immunopathology.

  3. CD4+/CD25+ regulatory cells inhibit activation of tumor-primed CD4+ T cells with IFN-gamma-dependent antiangiogenic activity, as well as long-lasting tumor immunity elicited by peptide vaccination.

    PubMed

    Casares, Noelia; Arribillaga, Laura; Sarobe, Pablo; Dotor, Javier; Lopez-Diaz de Cerio, Ascensión; Melero, Ignacio; Prieto, Jesús; Borrás-Cuesta, Francisco; Lasarte, Juan J

    2003-12-01

    CD25(+) regulatory T (T reg) cells suppress the activation/proliferation of other CD4(+) or CD8(+) T cells in vitro. Also, down-regulation of CD25(+) T reg cells enhance antitumor immune responses. In this study, we show that depletion of CD25(+) T reg cells allows the host to induce both CD4(+) and CD8(+) antitumoral responses following tumor challenge. Simultaneous depletion of CD25(+) and CD8(+) cells, as well as adoptive transfer experiments, revealed that tumor-specific CD4(+) T cells, which emerged in the absence of CD25(+) T reg cells, were able to reject CT26 colon cancer cells, a MHC class II-negative tumor. The antitumoral effect mediated by CD4(+) T cells was dependent on IFN-gamma production, which exerted a potent antiangiogenic activity. The capacity of the host to mount this antitumor response is lost once the number of CD25(+) T reg cells is restored over time. However, CD25(+) T reg cell depletion before immunization with AH1 (a cytotoxic T cell determinant from CT26 tumor cells) permits the induction of a long-lasting antitumoral immune response, not observed if immunization is conducted in the presence of regulatory cells. A study of the effect of different levels of depletion of CD25(+) T reg cells before immunization with the peptide AH1 alone, or in combination with a Th determinant, unraveled that Th cells play an important role in overcoming the suppressive effect of CD25(+) T reg on the induction of long-lasting cellular immune responses.

  4. Protection of ATP-Depleted Cells by Impermeant Strychnine Derivatives

    PubMed Central

    Dong, Zheng; Venkatachalam, Manjeri A.; Weinberg, Joel M.; Saikumar, Pothana; Patel, Yogendra

    2001-01-01

    Glycine and structurally related amino acids with activities at chloride channel receptors in the central nervous system also have robust protective effects against cell injury by ATP depletion. The glycine receptor antagonist strychnine shares this protective activity. An essential step toward identification of the molecular targets for these compounds is to determine whether they protect cells through interactions with intracellular targets or with molecules on the outer surface of plasma membranes. Here we report cytoprotection by a cell-impermeant derivative of strychnine. A strychnine-fluorescein conjugate (SF) was synthesized, and impermeability of plasma membranes to this compound was verified by fluorescence confocal microscopy. In an injury model of Madin-Darby canine kidney cells, ATP depletion led to lactate dehydrogenase release. SF prevented lactate dehydrogenase leakage without ameliorating ATP depletion. This was accompanied by preservation of cellular ultrastructure and exclusion of vital dyes. SF protection was also shown for ATP-depleted rat hepatocytes. On the other hand, when a key structural motif in the active site of strychnine was chemically blocked, the SF lost its protective effect, establishing strychnine-related specificity for SF protection. Cytoprotective effects of the cell-impermeant strychnine derivative provide compelling evidence suggesting that molecular targets on the outer surface of plasma membranes may mediate cytoprotection by strychnine and glycine. PMID:11238050

  5. Effective fiber hypertrophy in satellite cell-depleted skeletal muscle

    PubMed Central

    McCarthy, John J.; Mula, Jyothi; Miyazaki, Mitsunori; Erfani, Rod; Garrison, Kelcye; Farooqui, Amreen B.; Srikuea, Ratchakrit; Lawson, Benjamin A.; Grimes, Barry; Keller, Charles; Van Zant, Gary; Campbell, Kenneth S.; Esser, Karyn A.; Dupont-Versteegden, Esther E.; Peterson, Charlotte A.

    2011-01-01

    An important unresolved question in skeletal muscle plasticity is whether satellite cells are necessary for muscle fiber hypertrophy. To address this issue, a novel mouse strain (Pax7-DTA) was created which enabled the conditional ablation of >90% of satellite cells in mature skeletal muscle following tamoxifen administration. To test the hypothesis that satellite cells are necessary for skeletal muscle hypertrophy, the plantaris muscle of adult Pax7-DTA mice was subjected to mechanical overload by surgical removal of the synergist muscle. Following two weeks of overload, satellite cell-depleted muscle showed the same increases in muscle mass (approximately twofold) and fiber cross-sectional area with hypertrophy as observed in the vehicle-treated group. The typical increase in myonuclei with hypertrophy was absent in satellite cell-depleted fibers, resulting in expansion of the myonuclear domain. Consistent with lack of nuclear addition to enlarged fibers, long-term BrdU labeling showed a significant reduction in the number of BrdU-positive myonuclei in satellite cell-depleted muscle compared with vehicle-treated muscle. Single fiber functional analyses showed no difference in specific force, Ca2+ sensitivity, rate of cross-bridge cycling and cooperativity between hypertrophied fibers from vehicle and tamoxifen-treated groups. Although a small component of the hypertrophic response, both fiber hyperplasia and regeneration were significantly blunted following satellite cell depletion, indicating a distinct requirement for satellite cells during these processes. These results provide convincing evidence that skeletal muscle fibers are capable of mounting a robust hypertrophic response to mechanical overload that is not dependent on satellite cells. PMID:21828094

  6. Simian immunodeficiency virus selectively infects proliferating CD4+ T cells in neonatal rhesus macaques.

    PubMed

    Wang, Xiaolei; Xu, Huanbin; Pahar, Bapi; Alvarez, Xavier; Green, Linda C; Dufour, Jason; Moroney-Rasmussen, Terri; Lackner, Andrew A; Veazey, Ronald S

    2010-11-18

    Infants infected with HIV have a more severe course of disease and persistently higher viral loads than HIV-infected adults. However, the underlying pathogenesis of this exacerbation remains obscure. Here we compared the rate of CD4(+) and CD8(+) T-cell proliferation in intestinal and systemic lymphoid tissues of neonatal and adult rhesus macaques, and of normal and age-matched simian immunodeficiency virus (SIV)-infected neonates. The results demonstrate infant primates have much greater rates of CD4(+) T-cell proliferation than adult macaques, and that these proliferating, recently "activated" CD4(+) T cells are infected in intestinal and other lymphoid tissues of neonates, resulting in selective depletion of proliferating CD4(+) T cells in acute infection. This depletion is accompanied by a marked increase in CD8(+) T-cell activation and production, particularly in the intestinal tract. The data indicate intestinal CD4(+) T cells of infant primates have a markedly accelerated rate of proliferation and maturation resulting in more rapid and sustained production of optimal target cells (activated memory CD4(+) T cells), which may explain the sustained "peak" viremia characteristic of pediatric HIV infection. Eventual failure of CD4(+) T-cell turnover in intestinal tissues may indicate a poorer prognosis for HIV-infected infants.

  7. CD8 Follicular T Cells Promote B Cell Antibody Class Switch in Autoimmune Disease.

    PubMed

    Valentine, Kristen M; Davini, Dan; Lawrence, Travis J; Mullins, Genevieve N; Manansala, Miguel; Al-Kuhlani, Mufadhal; Pinney, James M; Davis, Jason K; Beaudin, Anna E; Sindi, Suzanne S; Gravano, David M; Hoyer, Katrina K

    2018-05-09

    CD8 T cells can play both a protective and pathogenic role in inflammation and autoimmune development. Recent studies have highlighted the ability of CD8 T cells to function as T follicular helper (Tfh) cells in the germinal center in the context of infection. However, whether this phenomenon occurs in autoimmunity and contributes to autoimmune pathogenesis is largely unexplored. In this study, we show that CD8 T cells acquire a CD4 Tfh profile in the absence of functional regulatory T cells in both the IL-2-deficient and scurfy mouse models. Depletion of CD8 T cells mitigates autoimmune pathogenesis in IL-2-deficient mice. CD8 T cells express the B cell follicle-localizing chemokine receptor CXCR5, a principal Tfh transcription factor Bcl6, and the Tfh effector cytokine IL-21. CD8 T cells localize to the B cell follicle, express B cell costimulatory proteins, and promote B cell differentiation and Ab isotype class switching. These data reveal a novel contribution of autoreactive CD8 T cells to autoimmune disease, in part, through CD4 follicular-like differentiation and functionality. Copyright © 2018 by The American Association of Immunologists, Inc.

  8. Simian immunodeficiency virus infection induces severe loss of intestinal central memory T cells which impairs CD4+ T-cell restoration during antiretroviral therapy.

    PubMed

    Verhoeven, D; Sankaran, S; Dandekar, S

    2007-08-01

    Simian immunodeficiency virus (SIV) infection leads to severe loss of intestinal CD4(+) T cells and, as compared to peripheral blood, restoration of these cells is slow during antiretroviral therapy (ART). Mechanisms for this delay have not been examined in context of which specific CD4(+) memory subsets or lost and fail to regenerate during ART. Fifteen rhesus macaques were infected with SIV, five of which received ART (FTC/PMPA) for 30 weeks. Viral loads were measured by real-time PCR. Flow cytometric analysis determined changes in T-cell subsets and their proliferative state. Changes in proliferative CD4(+) memory subsets during infection accelerated their depletion. This reduced the central memory CD4(+) T-cell pool and contributed to slow CD4(+) T-cell restoration during ART. There was a lack of restoration of the CD4(+) central memory and effector memory T-cell subsets in gut-associated lymphoid tissue during ART, which may contribute to the altered intestinal T-cell homeostasis in SIV infection.

  9. Progressive CD4+ central memory T cell decline results in CD4+ effector memory insufficiency and overt disease in chronic SIV infection.

    PubMed

    Okoye, Afam; Meier-Schellersheim, Martin; Brenchley, Jason M; Hagen, Shoko I; Walker, Joshua M; Rohankhedkar, Mukta; Lum, Richard; Edgar, John B; Planer, Shannon L; Legasse, Alfred; Sylwester, Andrew W; Piatak, Michael; Lifson, Jeffrey D; Maino, Vernon C; Sodora, Donald L; Douek, Daniel C; Axthelm, Michael K; Grossman, Zvi; Picker, Louis J

    2007-09-03

    Primary simian immunodeficiency virus (SIV) infections of rhesus macaques result in the dramatic depletion of CD4(+) CCR5(+) effector-memory T (T(EM)) cells from extra-lymphoid effector sites, but in most infections, an increased rate of CD4(+) memory T cell proliferation appears to prevent collapse of effector site CD4(+) T(EM) cell populations and acute-phase AIDS. Eventually, persistent SIV replication results in chronic-phase AIDS, but the responsible mechanisms remain controversial. Here, we demonstrate that in the chronic phase of progressive SIV infection, effector site CD4(+) T(EM) cell populations manifest a slow, continuous decline, and that the degree of this depletion remains a highly significant correlate of late-onset AIDS. We further show that due to persistent immune activation, effector site CD4(+) T(EM) cells are predominantly short-lived, and that their homeostasis is strikingly dependent on the production of new CD4(+) T(EM) cells from central-memory T (T(CM)) cell precursors. The instability of effector site CD4(+) T(EM) cell populations over time was not explained by increasing destruction of these cells, but rather was attributable to progressive reduction in their production, secondary to decreasing numbers of CCR5(-) CD4(+) T(CM) cells. These data suggest that although CD4(+) T(EM) cell depletion is a proximate mechanism of immunodeficiency, the tempo of this depletion and the timing of disease onset are largely determined by destruction, failing production, and gradual decline of CD4(+) T(CM) cells.

  10. Immunostimulatory Effects of Melphalan and Usefulness in Adoptive Cell Therapy with Antitumor CD4+ T Cells.

    PubMed

    Kuczma, Michal; Ding, Zhi-Chun; Zhou, Gang

    2016-01-01

    The alkylating agent melphalan is used in the treatment of hematological malignancies, especially multiple myeloma. In the past, the usefulness of melphalan has been solely attributed to its cytotoxicity on fastgrowing cancerous cells. Although the immunomodulatory effects of melphalan were suggested many years ago, only recently has this aspect of melphalan's activity begun to be elucidated at the molecular level. Emerging evidence indicates that melphalan can foster an immunogenic microenvironment by inducing immunogenic cell death (ICD) as characterized by membrane translocation of endoplasmic reticulum protein calreticulin (CRT) and by release of chromatin-binding protein high-mobility group box 1 (HMGB1). In addition, the lympho-depletive effect of melphalan can induce the release of pro-inflammatory cytokines and growth factors, deplete regulatory T cells, and create space to facilitate the expansion of infused tumor-reactive T cells. These features suggest that melphalan can be used as a preparative chemotherapy for adoptive T-cell therapy. This notion is supported by our recent work demonstrating that the combination of melphalan and adoptive transfer of tumor-reactive CD4+ T cells can mediate potent antitumor effects in animal models. This review summarizes the recent advances in understanding and utilizing the immunomodulatory effects of melphalan.

  11. Immunostimulatory Effects of Melphalan and Usefulness in Adoptive Cell Therapy with Antitumor CD4+ T Cells

    PubMed Central

    Kuczma, Michal; Ding, Zhi-Chun; Zhou, Gang

    2017-01-01

    The alkylating agent melphalan is used in the treatment of hematological malignancies, especially multiple myeloma. In the past, the usefulness of melphalan has been solely attributed to its cytotoxicity on fast-growing cancerous cells. Although the immunomodulatory effects of melphalan were suggested many years ago, only recently has this aspect of melphalan’s activity begun to be elucidated at the molecular level. Emerging evidence indicates that melphalan can foster an immunogenic microenvironment by inducing immunogenic cell death (ICD) as characterized by membrane translocation of endoplasmic reticulum protein calreticulin (CRT) and by release of chromatin-binding protein high-mobility group box 1 (HMGB1). In addition, the lympho-depletive effect of melphalan can induce the release of pro-inflammatory cytokines and growth factors, deplete regulatory T cells, and create space to facilitate the expansion of infused tumor-reactive T cells. These features suggest that melphalan can be used as a preparative chemotherapy for adoptive T-cell therapy. This notion is supported by our recent work demonstrating that the combination of melphalan and adoptive transfer of tumor-reactive CD4+ T cells can mediate potent antitumor effects in animal models. This review summarizes the recent advances in understanding and utilizing the immunomodulatory effects of melphalan. PMID:27910767

  12. T Cells Are Not Required for Pathogenesis in the Syrian Hamster Model of Hantavirus Pulmonary Syndrome ▿

    PubMed Central

    Hammerbeck, Christopher D.; Hooper, Jay W.

    2011-01-01

    Andes virus (ANDV) is associated with a lethal vascular leak syndrome in humans termed hantavirus pulmonary syndrome (HPS). In hamsters, ANDV causes a respiratory distress syndrome closely resembling human HPS. The mechanism for the massive vascular leakage associated with HPS is poorly understood; however, T cell immunopathology has been implicated on the basis of circumstantial and corollary evidence. Here, we show that following ANDV challenge, hamster T cell activation corresponds with the onset of disease. However, treatment with cyclophosphamide or specific T cell depletion does not impact the course of disease or alter the number of surviving animals, despite significant reductions in T cell number. These data demonstrate, for the first time, that T cells are not required for hantavirus pathogenesis in the hamster model of human HPS. Depletion of T cells from Syrian hamsters did not significantly influence early events in disease progression. Moreover, these data argue for a mechanism of hantavirus-induced vascular permeability that does not involve T cell immunopathology. PMID:21775442

  13. Calcium signaling properties of a thyrotroph cell line, mouse TαT1 cells.

    PubMed

    Tomić, Melanija; Bargi-Souza, Paula; Leiva-Salcedo, Elias; Nunes, Maria Tereza; Stojilkovic, Stanko S

    2015-12-01

    T1 cells are mouse thyrotroph cell line frequently used for studies on thyroid-stimulating hormone beta subunit gene expression and other cellular functions. Here we have characterized calcium-signaling pathways in TαT1 cells, an issue not previously addressed in these cells and incompletely described in native thyrotrophs. TαT1 cells are excitable and fire action potentials spontaneously and in response to application of thyrotropin-releasing hormone (TRH), the native hypothalamic agonist for thyrotrophs. Spontaneous electrical activity is coupled to small amplitude fluctuations in intracellular calcium, whereas TRH stimulates both calcium mobilization from intracellular pools and calcium influx. Non-receptor-mediated depletion of intracellular pool also leads to a prominent facilitation of calcium influx. Both receptor and non-receptor stimulated calcium influx is substantially attenuated but not completely abolished by inhibition of voltage-gated calcium channels, suggesting that depletion of intracellular calcium pool in these cells provides a signal for both voltage-independent and -dependent calcium influx, the latter by facilitating the pacemaking activity. These cells also express purinergic P2Y1 receptors and their activation by extracellular ATP mimics TRH action on calcium mobilization and influx. The thyroid hormone triiodothyronine prolongs duration of TRH-induced calcium spikes during 30-min exposure. These data indicate that TαT1 cells are capable of responding to natively feed-forward TRH signaling and intrapituitary ATP signaling with acute calcium mobilization and sustained calcium influx. Amplification of TRH-induced calcium signaling by triiodothyronine further suggests the existence of a pathway for positive feedback effects of thyroid hormones probably in a non-genomic manner. Published by Elsevier Ltd.

  14. Serum BAFF and APRIL Levels, T-Lymphocyte Subsets, and Immunoglobulins after B-Cell Depletion Using the Monoclonal Anti-CD20 Antibody Rituximab in Myalgic Encephalopathy/Chronic Fatigue Syndrome

    PubMed Central

    Lunde, Sigrid; Kristoffersen, Einar K.; Sapkota, Dipak; Risa, Kristin; Dahl, Olav; Bruland, Ove; Mella, Olav; Fluge, Øystein

    2016-01-01

    Myalgic Encephalopathy/Chronic Fatigue Syndrome (ME/CFS) is a disease of unknown etiology. We have previously suggested clinical benefit from B-cell depletion using the monoclonal anti-CD20 antibody rituximab in a randomized and placebo-controlled study. Prolonged responses were then demonstrated in an open-label phase-II study with maintenance rituximab treatment. Using blood samples from patients in the previous two clinical trials, we investigated quantitative changes in T-lymphocyte subsets, in immunoglobulins, and in serum levels of two B-cell regulating cytokines during follow-up. B-lymphocyte activating factor of the tumor necrosis family (BAFF) in baseline serum samples was elevated in 70 ME/CFS patients as compared to 56 healthy controls (p = 0.011). There were no significant differences in baseline serum BAFF levels between patients with mild, moderate, or severe ME/CFS, or between responders and non-responders to rituximab. A proliferation-inducing ligand (APRIL) serum levels were not significantly different in ME/CFS patients compared to healthy controls at baseline, and no changes in serum levels were seen during follow-up. Immunophenotyping of peripheral blood T-lymphocyte subsets and T-cell activation markers at multiple time points during follow-up showed no significant differences over time, between rituximab and placebo groups, or between responders and non-responders to rituximab. Baseline serum IgG levels were significantly lower in patients with subsequent response after rituximab therapy compared to non-responders (p = 0.03). In the maintenance study, slight but significant reductions in mean serum immunoglobulin levels were observed at 24 months compared to baseline; IgG 10.6–9.5 g/L, IgA 1.8–1.5 g/L, and IgM 0.97–0.70 g/L. Although no functional assays were performed, the lack of significant associations of T- and NK-cell subset numbers with B-cell depletion, as well as the lack of associations to clinical responses, suggest that B-cell

  15. The effect of induction therapy on established CMV specific T cell immunity in living donor kidney transplantation.

    PubMed

    Stranavova, L; Hruba, P; Girmanova, E; Tycova, I; Slavcev, A; Fronek, J; Slatinska, J; Reinke, P; Volk, H-D; Viklicky, O

    2018-05-04

    Cytomegalovirus (CMV) infection influences both short and long term outcomes in immunosuppressed organ transplant recipients. The aim of this study was to evaluate the effect of different induction immunosuppression regimens on CMV specific T cell response in patients with already established CMV immunity. In 24 seropositive living donor kidney recipients, the frequency of CMV specific T cells was determined by ELISPOT (Enzyme-Linked ImmunoSpot) assay prior and 6 months after transplantation. Recipients' peripheral blood mononuclear cells were stimulated with immediate-early (IE1) and phosphoprotein 65 (pp65) CMV-derived peptide pools and the number of cells producing interferon gamma (IFN-gamma) was assessed. Patients received quadruple immunosuppression based either on depletive rabbit antithymocyte globulin (rATG) or non-depletive basiliximab induction and tacrolimus/mycophenolate mofetil/steroids. Patients with rATG induction received valgancyclovir prophylaxis. No effects of different induction agents on CMV specific T cell immunity were found at sixth month after kidney transplantation. There were no associations among dialysis vintage, pretransplant CMV specific T cell immunity, and later CMV DNAemia. Similarly, no effect of CMV prophylaxis on CMV specific T cell immunity was revealed. This study shows no effect of posttransplant immunosuppression on CMV specific T cell immunity in living donor kidney transplant recipients with CMV immunity already established, regardless of lymphocyte depletion and CMV prophylaxis.

  16. Bone marrow–based homeostatic proliferation of mature T cells in nonhuman primates: implications for AIDS pathogenesis

    PubMed Central

    Paiardini, Mirko; Cervasi, Barbara; Engram, Jessica C.; Gordon, Shari N.; Klatt, Nichole R.; Muthukumar, Alagarraju; Else, James; Mittler, Robert S.; Staprans, Silvija I.; Sodora, Donald L.

    2009-01-01

    Bone marrow (BM) is the key hematopoietic organ in mammals and is involved in the homeostatic proliferation of memory CD8+ T cells. Here we expanded on our previous observation that BM is a preferential site for T-cell proliferation in simian immunodeficiency virus (SIV)–infected sooty mangabeys (SMs) that do not progress to AIDS despite high viremia. We found high levels of mature T-cell proliferation, involving both naive and memory cells, in healthy SMs and rhesus macaques (RMs). In addition, we observed in both species that lineage-specific, BM-based T-cell proliferation follows antibody-mediated in vivo CD4+ or CD8+ T-cell depletion, thus indicating a role for the BM in maintaining T-cell homeostasis under depleting circumstances. We also observed that, in SIV-infected SMs, but not RMs, the level of proliferation of BM-based CD4+ T cells is higher than that of circulating CD4+ T cells. Interestingly, limited BM-based CD4+ T-cell proliferation was found in SIV-infected SMs with low CD4+ T-cell counts, suggesting a regenerative failure in these animals. Collectively, these results indicate that BM is involved in maintaining T-cell homeostasis in primates and suggest a role for BM-based CD4+ T-cell proliferation in determining the benign nature of natural SIV infection of SMs. PMID:18832134

  17. Bone marrow-based homeostatic proliferation of mature T cells in nonhuman primates: implications for AIDS pathogenesis.

    PubMed

    Paiardini, Mirko; Cervasi, Barbara; Engram, Jessica C; Gordon, Shari N; Klatt, Nichole R; Muthukumar, Alagarraju; Else, James; Mittler, Robert S; Staprans, Silvija I; Sodora, Donald L; Silvestri, Guido

    2009-01-15

    Bone marrow (BM) is the key hematopoietic organ in mammals and is involved in the homeostatic proliferation of memory CD8(+) T cells. Here we expanded on our previous observation that BM is a preferential site for T-cell proliferation in simian immunodeficiency virus (SIV)-infected sooty mangabeys (SMs) that do not progress to AIDS despite high viremia. We found high levels of mature T-cell proliferation, involving both naive and memory cells, in healthy SMs and rhesus macaques (RMs). In addition, we observed in both species that lineage-specific, BM-based T-cell proliferation follows antibody-mediated in vivo CD4(+) or CD8(+) T-cell depletion, thus indicating a role for the BM in maintaining T-cell homeostasis under depleting circumstances. We also observed that, in SIV-infected SMs, but not RMs, the level of proliferation of BM-based CD4(+) T cells is higher than that of circulating CD4(+) T cells. Interestingly, limited BM-based CD4(+) T-cell proliferation was found in SIV-infected SMs with low CD4(+) T-cell counts, suggesting a regenerative failure in these animals. Collectively, these results indicate that BM is involved in maintaining T-cell homeostasis in primates and suggest a role for BM-based CD4(+) T-cell proliferation in determining the benign nature of natural SIV infection of SMs.

  18. Inotuzumab Ozogamicin Murine Analog–Mediated B-Cell Depletion Reduces Anti-islet Allo- and Autoimmune Responses

    PubMed Central

    Carvello, Michele; Petrelli, Alessandra; Vergani, Andrea; Lee, Kang Mi; Tezza, Sara; Chin, Melissa; Orsenigo, Elena; Staudacher, Carlo; Secchi, Antonio; Dunussi-Joannopoulos, Kyri; Sayegh, Mohamed H.; Markmann, James F.; Fiorina, Paolo

    2012-01-01

    B cells participate in the priming of the allo- and autoimmune responses, and their depletion can thus be advantageous for islet transplantation. Herein, we provide an extensive study of the effect of B-cell depletion in murine models of islet transplantation. Islet transplantation was performed in hyperglycemic B-cell–deficient(μMT) mice, in a purely alloimmune setting (BALB/c into hyperglycemic C57BL/6), in a purely autoimmune setting (NOD.SCID into hyperglycemic NOD), and in a mixed allo-/autoimmune setting (BALB/c into hyperglycemic NOD). Inotuzumab ozogamicin murine analog (anti-CD22 monoclonal antibody conjugated with calicheamicin [anti-CD22/cal]) efficiently depleted B cells in all three models of islet transplantation examined. Islet graft survival was significantly prolonged in B-cell–depleted mice compared with control groups in transplants of islets from BALB/c into C57BL/6 (mean survival time [MST]: 16.5 vs. 12.0 days; P = 0.004), from NOD.SCID into NOD (MST: 23.5 vs. 14.0 days; P = 0.03), and from BALB/c into NOD (MST: 12.0 vs. 5.5 days; P = 0.003). In the BALB/c into B-cell–deficient mice model, islet survival was prolonged as well (MST: μMT = 32.5 vs. WT = 14 days; P = 0.002). Pathology revealed reduced CD3+ cell islet infiltration and confirmed the absence of B cells in treated mice. Mechanistically, effector T cells were reduced in number, concomitant with a peripheral Th2 profile skewing and ex vivo recipient hyporesponsiveness toward donor-derived antigen as well as islet autoantigens. Finally, an anti-CD22/cal and CTLA4-Ig–based combination therapy displayed remarkable prolongation of graft survival in the stringent model of islet transplantation (BALB/c into NOD). Anti-CD22/cal–mediated B-cell depletion promotes the reduction of the anti-islet immune response in various models of islet transplantation. PMID:22076927

  19. Memory T cells in organ transplantation: progress and challenges

    PubMed Central

    Espinosa, Jaclyn R.; Samy, Kannan P.; Kirk, Allan D.

    2017-01-01

    Antigen-experienced T cells, also known as memory T cells, are functionally and phenotypically distinct from naive T cells. Their enhanced expression of adhesion molecules and reduced requirement for co-stimulation enables them to mount potent and rapid recall responses to subsequent antigen encounters. Memory T cells generated in response to prior antigen exposures can cross-react with other nonidentical, but similar, antigens. This heterologous cross-reactivity not only enhances protective immune responses, but also engenders de novo alloimmunity. This latter characteristic is increasingly recognized as a potential barrier to allograft acceptance that is worthy of immunotherapeutic intervention, and several approaches have been investigated. Calcineurin inhibition effectively controls memory T-cell responses to allografts, but this benefit comes at the expense of increased infectious morbidity. Lymphocyte depletion eliminates allospecific T cells but spares memory T cells to some extent, such that patients do not completely lose protective immunity. Co-stimulation blockade is associated with reduced adverse-effect profiles and improved graft function relative to calcineurin inhibition, but lacks efficacy in controlling memory T-cell responses. Targeting the adhesion molecules that are upregulated on memory T cells might offer additional means to control co-stimulation-blockade-resistant memory T-cell responses. PMID:26923209

  20. Fibrin facilitates both innate and T cell-mediated defense against Yersinia pestis.1

    PubMed Central

    Luo, Deyan; Lin, Shiuan; Parent, Michelle A.; Kanevsky, Isis Mullarky; Szaba, Frank M.; Kummer, Lawrence W.; Duso, Debra K.; Tighe, Michael; Hill, Jim; Gruber, Andras; Mackman, Nigel; Gailani, David; Smiley, Stephen T.

    2013-01-01

    The gram-negative bacterium Yersinia pestis causes plague, a rapidly progressing and often fatal disease. The formation of fibrin at sites of Y. pestis infection supports innate host defense against plague, perhaps by providing a non-diffusible spatial cue that promotes the accumulation of inflammatory cells expressing fibrin-binding integrins. This report demonstrates that fibrin is an essential component of T cell-mediated defense against plague but can be dispensable for antibody-mediated defense. Genetic or pharmacologic depletion of fibrin abrogated innate and T cell-mediated defense in mice challenged intranasally with Y. pestis. The fibrin-deficient mice displayed reduced survival, increased bacterial burden, and exacerbated hemorrhagic pathology. They also showed fewer neutrophils within infected lung tissue and reduced neutrophil viability at sites of liver infection. Depletion of neutrophils from wild type mice weakened T cell-mediated defense against plague. The data suggest that T cells combat plague in conjunction with neutrophils, which require help from fibrin in order to withstand Y. pestis encounters and effectively clear bacteria. PMID:23487423

  1. Therapeutic targeting of regulatory T cells enhances tumor-specific CD8+ T cell responses in Epstein–Barr virus associated nasopharyngeal carcinoma

    PubMed Central

    Fogg, Mark; Murphy, John R.; Lorch, Jochen; Posner, Marshall; Wang, Fred

    2013-01-01

    Epstein–Barr virus (EBV) is associated with multiple malignancies including nasopharyngeal carcinoma (NPC). In nasopharynx cancer, CD8+ T cells specific for EBV Nuclear Antigen-1 (EBNA-1) and Latent Membrane Protein 2 (LMP2) are important components of anti-tumor immunity since both are consistently expressed in NPC. We have previously shown that EBNA-1-specific CD8+ T cell responses were suppressed in NPC patients compared to healthy controls. We now find that CD8+ T cell responses specific for LMP2 are also abnormal in NPC patients, and both EBNA-1- and LMP2-specific responses are suppressed by regulatory T cells (Treg). EBNA-1 and LMP2-specific CD8+ T cell responses, as well as immune control of EBV-infected cells in vitro, could be restored by the depletion of Tregs and by use of a clinically approved drug targeting Tregs. Thus, in vivo modulation of Tregs may be an effective means of enhancing these anti-tumor immune responses in NPC patients. PMID:23601786

  2. T Cells Prevent Hemorrhagic Transformation in Ischemic Stroke by P-Selectin Binding.

    PubMed

    Salas-Perdomo, Angélica; Miró-Mur, Francesc; Urra, Xabier; Justicia, Carles; Gallizioli, Mattia; Zhao, Yashu; Brait, Vanessa H; Laredo, Carlos; Tudela, Raúl; Hidalgo, Andrés; Chamorro, Ángel; Planas, Anna M

    2018-06-14

    Hemorrhagic transformation is a serious complication of ischemic stroke after recanalization therapies. This study aims to identify mechanisms underlying hemorrhagic transformation after cerebral ischemia/reperfusion. We used wild-type mice and Selplg -/- and Fut7 -/- mice defective in P-selectin binding and lymphopenic Rag2 -/- mice. We induced 30-minute or 45-minute ischemia by intraluminal occlusion of the middle cerebral artery and assessed hemorrhagic transformation at 48 hours with a hemorrhage grading score, histological means, brain hemoglobin content, or magnetic resonance imaging. We depleted platelets and adoptively transferred T cells of the different genotypes to lymphopenic mice. Interactions of T cells with platelets in blood were studied by flow cytometry and image stream technology. We show that platelet depletion increased the bleeding risk only after large infarcts. Lymphopenia predisposed to hemorrhagic transformation after severe stroke, and adoptive transfer of T cells prevented hemorrhagic transformation in lymphopenic mice. CD4 + memory T cells were the subset of T cells binding P-selectin and platelets through functional P-selectin glycoprotein ligand-1. Mice defective in P-selectin binding had a higher hemorrhagic score than wild-type mice. Adoptive transfer of T cells defective in P-selectin binding into lymphopenic mice did not prevent hemorrhagic transformation. The study identifies lymphopenia as a previously unrecognized risk factor for secondary hemorrhagic transformation in mice after severe ischemic stroke. T cells prevent hemorrhagic transformation by their capacity to bind platelets through P-selectin. The results highlight the role of T cells in bridging immunity and hemostasis in ischemic stroke. © 2018 American Heart Association, Inc.

  3. MtDNA depleted PC3 cells exhibit Warburg effect and cancer stem cell features

    PubMed Central

    Li, Xiaoran; Zhong, Yali; Lu, Jie; Axcrona, Karol; Eide, Lars; Syljuåsen, Randi G.; Peng, Qian; Wang, Junbai; Zhang, Hongquan; Goscinski, Mariusz Adam; Kvalheim, Gunnar; Nesland, Jahn M.; Suo, Zhenhe

    2016-01-01

    Reducing mtDNA content was considered as a critical step in the metabolism restructuring for cell stemness restoration and further neoplastic development. However, the connections between mtDNA depletion and metabolism reprograming-based cancer cell stemness in prostate cancers are still lack of studies. Here, we demonstrated that human CRPC cell line PC3 tolerated high concentration of the mtDNA replication inhibitor ethidium bromide (EtBr) and the mtDNA depletion triggered a universal metabolic remodeling process. Failure in completing that process caused lethal consequences. The mtDNA depleted (MtDP) PC3 cells could be steadily maintained in the special medium in slow cycling status. The MtDP PC3 cells contained immature mitochondria and exhibited Warburg effect. Furthermore, the MtDP PC3 cells were resistant to therapeutic treatments and contained greater cancer stem cell-like subpopulations: CD44+, ABCG2+, side-population and ALDHbright. In conclusion, these results highlight the association of mtDNA content, mitochondrial function and cancer cell stemness features. PMID:27248169

  4. Identifying the Target Cell in Primary Simian Immunodeficiency Virus (SIV) Infection: Highly Activated Memory CD4+ T Cells Are Rapidly Eliminated in Early SIV Infection In Vivo

    PubMed Central

    Veazey, Ronald S.; Tham, Irene C.; Mansfield, Keith G.; DeMaria, MaryAnn; Forand, Amy E.; Shvetz, Daniel E.; Chalifoux, Laura V.; Sehgal, Prabhat K.; Lackner, Andrew A.

    2000-01-01

    It has recently been shown that rapid and profound CD4+ T-cell depletion occurs almost exclusively within the intestinal tract of simian immunodeficiency virus (SIV)-infected macaques within days of infection. Here we demonstrate (by three- and four-color flow cytometry) that this depletion is specific to a definable subset of CD4+ T cells, namely, those having both a highly and/or acutely activated (CD69+ CD38+ HLA-DR+) and memory (CD45RA− Leu8−) phenotype. Moreover, we demonstrate that this subset of helper T cells is found primarily within the intestinal lamina propria. Viral tropism for this particular cell type (which has been previously suggested by various studies in vitro) could explain why profound CD4+ T-cell depletion occurs in the intestine and not in peripheral lymphoid tissues in early SIV infection. Furthermore, we demonstrate that an acute loss of this specific subset of activated memory CD4+ T cells may also be detected in peripheral blood and lymph nodes in early SIV infection. However, since this particular cell type is present in such small numbers in circulation, its loss does not significantly affect total CD4+ T cell counts. This finding suggests that SIV and, presumably, human immunodeficiency virus specifically infect, replicate in, and eliminate definable subsets of CD4+ T cells in vivo. PMID:10590091

  5. Repeated B cell depletion in treatment of refractory systemic lupus erythematosus

    PubMed Central

    Ng, K P; Leandro, M J; Edwards, J C; Ehrenstein, M R; Cambridge, G; Isenberg, D A

    2006-01-01

    Objectives To report the clinical outcome and safety profile of repeated B cell depletion in seven patients with refractory systemic lupus erythematosus (SLE). Methods Since June 2000, seven patients with refractory SLE had repeated cycles of B cell depletion (18 cycles in total, up to three cycles per patient) because of disease relapse. The clinical response (assessed by the British Isles Lupus Activity Guide (BILAG) activity index), duration of B cell depletion, and adverse events in these patients was reviewed. Results Four patients (Nos 1, 2, 3, 6) had three cycles of treatment and three (Nos 4, 5, 7) had two cycles. Four of the seven patients (Nos 1, 3, 5, 6) improved. The mean global BILAG scores dropped from 15 to 6 at 5–7 months. The median duration of clinical response and B cell depletion was 13 months and 6 months, respectively. After the third cycle, 2/4 patients (Nos 1 and 2) improved. The median duration of clinical benefit was 12 months. Most patients tolerate re‐treatment very well. Conclusion Re‐treatment with B cell depletion of patients with severe SLE is safe and may be effective for 6–12 months on average. PMID:16269424

  6. Crosslinking CD4 by human immunodeficiency virus gp120 primes T cells for activation-induced apoptosis

    PubMed Central

    1992-01-01

    During human immunodeficiency virus (HIV) infection there is a profound and selective decrease in the CD4+ population of T lymphocytes. The mechanism of this depletion is not understood, as only a small fraction of all CD4+ cells appear to be productively infected with HIV-1 in seropositive individuals. In the present study, crosslinking of bound gp120 on human CD4+ T cells followed by signaling through the T cell receptor for antigen was found to result in activation-dependent cell death by a form of cell suicide termed apoptosis, or programmed cell death. The data indicate that even picomolar concentrations of gp120 prime T cells for activation-induced cell death, suggesting a mechanism for CD4+ T cell depletion in acquired immune deficiency syndrome (AIDS), particularly in the face of concurrent infection and antigenic challenge with other organisms. These results also provide an explanation for the enhancement of infection by certain antibodies against HIV, and for the paradox that HIV appears to cause AIDS after the onset of antiviral immunity. PMID:1402655

  7. Combined Haploidentical and Umbilical Cord Blood Allogeneic Stem Cell Transplantation for High-Risk Lymphoma and Chronic Lymphoblastic Leukemia.

    PubMed

    Hsu, Jingmei; Artz, Andrew; Mayer, Sebastian A; Guarner, Danielle; Bishop, Michael R; Reich-Slotky, Ronit; Smith, Sonali M; Greenberg, June; Kline, Justin; Ferrante, Rosanna; Phillips, Adrienne A; Gergis, Usama; Liu, Hongtao; Stock, Wendy; Cushing, Melissa; Shore, Tsiporah B; van Besien, Koen

    2018-02-01

    Limited studies have reported on outcomes for lymphoid malignancy patients receiving alternative donor allogeneic stem cell transplants. We have previously described combining CD34-selected haploidentical grafts with umbilical cord blood (haplo-cord) to accelerate neutrophil and platelet engraftment. Here, we examine the outcome of patients with lymphoid malignancies undergoing haplo-cord transplantation at the University of Chicago and Weill Cornell Medical College. We analyzed 42 lymphoma and chronic lymphoblastic leukemia (CLL) patients who underwent haplo-cord allogeneic stem cell transplantation. Patients underwent transplant for Hodgkin lymphoma (n = 9, 21%), CLL (n = 5, 12%) and non-Hodgkin lymphomas (n = 28, 67%), including 13 T cell lymphomas. Twenty-four patients (52%) had 3 or more lines of therapies. Six (14%) and 1 (2%) patients had prior autologous and allogeneic stem cell transplant, respectively. At the time of transplant 12 patients (29%) were in complete remission, 18 had chemotherapy-sensitive disease, and 12 patients had chemotherapy-resistant disease. Seven (17%), 11 (26%), and 24 (57%) patients had low, intermediate, and high disease risk index before transplant. Comorbidity index was evenly distributed among 3 groups, with 13 (31%), 14 (33%), and 15 (36%) patients scoring 0, 1 to 2, and ≥3. Median age for the cohort was 49 years (range, 23 to 71). All patients received fludarabine/melphalan/antithymocyte globulin conditioning regimen and post-transplant graft-versus-host disease (GVHD) prophylaxis with tacrolimus and mycophenolate mofetil. The median time to neutrophil engraftment was 11 days (range, 9 to 60) and to platelet engraftment 19.5 days (range, 11 to 88). Cumulative incidence of nonrelapse mortality was 11.6% at 100 days and 19 % at one year. Cumulative incidence of relapse was 9.3% at 100 days and 19% at one year. With a median follow-up of survivors of 42 months, the 3-year rates of GVHD relapse free survival

  8. T Follicular Helper Cell Plasticity Shapes Pathogenic T Helper 2 Cell-Mediated Immunity to Inhaled House Dust Mite.

    PubMed

    Ballesteros-Tato, André; Randall, Troy D; Lund, Frances E; Spolski, Rosanne; Leonard, Warren J; León, Beatriz

    2016-02-16

    Exposure to environmental antigens, such as house dust mite (HDM), often leads to T helper 2 (Th2) cell-driven allergic responses. However, the mechanisms underlying the development of these responses are incompletely understood. We found that the initial exposure to HDM did not lead to Th2 cell development but instead promoted the formation of interleukin-4 (IL-4)-committed T follicular helper (Tfh) cells. Following challenge exposure to HDM, Tfh cells differentiated into IL-4 and IL-13 double-producing Th2 cells that accumulated in the lung and recruited eosinophils. B cells were required to expand IL-4-committed Tfh cells during the sensitization phase, but did not directly contribute to disease. Impairment of Tfh cell responses during the sensitization phase or Tfh cell depletion prevented Th2 cell-mediated responses following challenge. Thus, our data demonstrate that Tfh cells are precursors of HDM-specific Th2 cells and reveal an unexpected role of B cells and Tfh cells in the pathogenesis of allergic asthma. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Methyl-donor depletion of head and neck cancer cells in vitro establishes a less aggressive tumour cell phenotype.

    PubMed

    Hearnden, Vanessa; Powers, Hilary J; Elmogassabi, Abeir; Lowe, Rosanna; Murdoch, Craig

    2018-06-01

    DNA methylation plays a fundamental role in the epigenetic control of carcinogenesis and is, in part, influenced by the availability of methyl donors obtained from the diet. In this study, we developed an in-vitro model to investigate whether methyl donor depletion affects the phenotype and gene expression in head and neck squamous cell carcinoma (HNSCC) cells. HNSCC cell lines (UD-SCC2 and UPCI-SCC72) were cultured in medium deficient in methionine, folate, and choline or methyl donor complete medium. Cell doubling-time, proliferation, migration, and apoptosis were analysed. The effects of methyl donor depletion on enzymes controlling DNA methylation and the pro-apoptotic factors death-associated protein kinase-1 (DAPK1) and p53 upregulated modulator of apoptosis (PUMA) were examined by quantitative-PCR or immunoblotting. HNSCC cells cultured in methyl donor deplete conditions showed significantly increased cell doubling times, reduced cell proliferation, impaired cell migration, and a dose-dependent increase in apoptosis when compared to cells cultured in complete medium. Methyl donor depletion significantly increased the gene expression of DNMT3a and TET-1, an effect that was reversed upon methyl donor repletion in UD-SCC2 cells. In addition, expression of DAPK1 and PUMA was increased in UD-SCC2 cells cultured in methyl donor deplete compared to complete medium, possibly explaining the observed increase in apoptosis in these cells. Taken together, these data show that depleting HNSCC cells of methyl donors reduces the growth and mobility of HNSCC cells, while increasing rates of apoptosis, suggesting that a methyl donor depleted diet may significantly affect the growth of established HNSCC.

  10. Autoreactive T Cells and Chronic Fungal Infection Drive Esophageal Carcinogenesis

    PubMed Central

    Zhu, Feng; Willette-Brown, Jami; Song, Na-Young; Lomada, Dakshayani; Song, Yongmei; Xue, Liyan; Gray, Zane; Zhao, Zitong; Davis, Sean R.; Sun, Zhonghe; Zhang, Peilin; Wu, Xiaolin; Zhan, Qimin; Richie, Ellen R.; Hu, Yinling

    2018-01-01

    SUMMARY Humans with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), a T cell–driven autoimmune disease caused by impaired central tolerance, are susceptible to developing chronic fungal infection and esophageal squamous cell carcinoma (ESCC). However, the relationship between autoreactive T cells and chronic fungal infection in ESCC development remains unclear. We find that kinase-dead Ikkα knockin mice develop phenotypes reminiscent of APECED, including impaired central tolerance, autoreactive T cells, chronic fungal infection, and ESCCs expressing specific human ESCC markers. Using this model, we investigated the potential link between ESCC and fungal infection. Autoreactive CD4 T cells permit fungal infection and incite tissue injury and inflammation. Antifungal treatment or depletion of autoreactive CD4 T cells rescues, whereas oral fungal administration promotes, ESCC development. Inhibition of inflammation or EGFR activity decreases fungal burden. Importantly, fungal infection is highly associated with ESCCs in non-autoimmune human patients. Therefore, autoreactive T cells and chronic fungal infection, fostered by inflammation and epithelial injury, promote ESCC development. PMID:28407484

  11. Radiosensitization of Hypoxic Tumor Cells by Depletion of Intracellular Glutathione

    NASA Astrophysics Data System (ADS)

    Bump, Edward A.; Yu, Ning Y.; Brown, J. Martin

    1982-08-01

    Depletion of glutathione in Chinese hamster ovary cells in vitro by diethyl maleate resulted in enhancement of the effect of x-rays on cell survival under hypoxic conditions but not under oxygenated conditions. Hypoxic EMT6 tumor cells were similarly sensitized in vivo. The action of diethyl maleate is synergistic with the effect of the electron-affinic radiosensitizer misonidazole, suggesting that the effectiveness of misonidazole in cancer radiotherapy may be improved by combining it with drugs that deplete intracellular glutathione.

  12. Radiosensitization of hypoxic tumor cells by depletion of intracellular glutathione

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bump, E.A.; Yu, N.Y.; Brown, J.M.

    1982-08-06

    Depletion of glutathione in Chinese hamster ovary cells in vitro by diethyl maleate resulted in enhancement of the effect of x-rays on cell survival under hypoxic conditions but not under oxygenated conditions. Hypoxic EMT6 tumor cells were similarly sensitized in vivo. The action of diethyl maleate is synergistic with the effect of the electron-affinic radiosensitizer misonidazole, suggesting that the effectiveness of misonidazole in cancer radiotherapy may be improved by combining it with drugs that deplete intracellular glutathione.

  13. Early Increases in Superantigen-Specific Foxp3+ Regulatory T Cells during Mouse Mammary Tumor Virus Infection▿ †

    PubMed Central

    Cabrera, Gabriel; Burzyn, Dalia; Mundiñano, Juliana; Courreges, M. Cecilia; Camicia, Gabriela; Lorenzo, Daniela; Costa, Héctor; Ross, Susan R.; Nepomnaschy, Irene; Piazzon, Isabel

    2008-01-01

    Mouse mammary tumor virus (MMTV) is a milk-borne betaretrovirus that has developed strategies to exploit and subvert the host immune system. Here, we show in a natural model of MMTV infection that the virus causes early and progressive increases in superantigen (SAg)-specific Foxp3+ regulatory T cells (Treg) in Peyer's patches (PP). These increases were shown to be dependent on the presence of dendritic cells. CD4+ CD25+ T cells from the PP of infected mice preferentially suppress the proliferative response of T cells to SAg-expressing antigen-presenting cells ex vivo. We investigated the influence of the depletion of CD25+ cells at different stages of the infection. When CD25+ cells were depleted before MMTV infection, an increase in the number of PP SAg-cognate Foxp3− T cells was found at day 6 of infection. Since the SAg response is associated with viral amplification, the possibility exists that Treg cells attenuate the increase in viral load at the beginning of the infection. In contrast, depletion of CD25+ cells once the initial SAg response has developed caused a lower viral load, suggesting that at later stages Treg cells may favor viral persistence. Thus, our results indicated that Treg cells play an important and complex role during MMTV infection. PMID:18495774

  14. Depletion of CD4 T Lymphocytes at the time of infection with M. avium subsp. paratuberculosis does not accelerate disease progression

    USDA-ARS?s Scientific Manuscript database

    A calf model was used to determine if the depletion of CD4 T cells prior to inoculation of Mycobacterium avium subsp. paratuberculosis (Map) would delay development of an immune response to Map and accelerate disease progression. Ileal cannulas were surgically implanted in 5 bull calves at two month...

  15. The exhausted CD4+CXCR5+ T cells involve the pathogenesis of human tuberculosis disease.

    PubMed

    Bosco, Munyemana Jean; Wei, Ming; Hou, Hongyan; Yu, Jing; Lin, Qun; Luo, Ying; Sun, Ziyong; Wang, Feng

    2018-06-21

    The CD4 + CXCR5 + T cells have been previously established. However, their decreased frequency during tuberculosis (TB) disease is partially understood. The aim of this study was to explore the depletion of CD4 + CXCR5 + T cells in human TB. The frequency and function of CD4 + CXCR5 + T cells were evaluated in active TB (ATB) patients and healthy control (HC) individuals. The function of CD4 + CXCR5 + T cells was determined after blockade of inhibitory receptors. The frequency of CD4 + CXCR5 + T cells was decreased in ATB patients. The expression of activation markers (HLA-DR and ICOS) and inhibitory receptors (Tim-3 and PD-1) on CD4 + CXCR5 + T cells was increased in ATB group. TB-specific antigen stimulation induced higher expression of inhibitory receptors than phytohemagglutinin stimulation in ATB group. In contrast, TB antigen stimulation did not induce a significantly increased expression of IL-21 and Ki-67 on CD4 + CXCR5 + T cells. However, blockade of inhibitory receptors Tim-3 and PD-1 not only increased the frequency of CD4 + CXCR5 + T cells, but also restored their proliferation and cytokine secretion potential. An increased expression of inhibitory receptors involves the depletion of CD4 + CXCR5 + T cells, and blockade of inhibitory receptors can restore the function of CD4 + CXCR5 + T cells in ATB patients. Copyright © 2018. Published by Elsevier Ltd.

  16. Longitudinal characterization of dysfunctional T cell-activation during human acute Ebola infection

    PubMed Central

    Agrati, C; Castilletti, C; Casetti, R; Sacchi, A; Falasca, L; Turchi, F; Tumino, N; Bordoni, V; Cimini, E; Viola, D; Lalle, E; Bordi, L; Lanini, S; Martini, F; Nicastri, E; Petrosillo, N; Puro, V; Piacentini, M; Di Caro, A; Kobinger, G P; Zumla, A; Ippolito, G; Capobianchi, M R

    2016-01-01

    Data on immune responses during human Ebola virus disease (EVD) are scanty, due to limitations imposed by biosafety requirements and logistics. A sustained activation of T-cells was recently described but functional studies during the acute phase of human EVD are still missing. Aim of this work was to evaluate the kinetics and functionality of T-cell subsets, as well as the expression of activation, autophagy, apoptosis and exhaustion markers during the acute phase of EVD until recovery. Two EVD patients admitted to the Italian National Institute for Infectious Diseases, Lazzaro Spallanzani, were sampled sequentially from soon after symptom onset until recovery and analyzed by flow cytometry and ELISpot assay. An early and sustained decrease of CD4 T-cells was seen in both patients, with an inversion of the CD4/CD8 ratio that was reverted during the recovery period. In parallel with the CD4 T-cell depletion, a massive T-cell activation occurred and was associated with autophagic/apoptotic phenotype, enhanced expression of the exhaustion marker PD-1 and impaired IFN-gamma production. The immunological impairment was accompanied by EBV reactivation. The association of an early and sustained dysfunctional T-cell activation in parallel to an overall CD4 T-cell decline may represent a previously unknown critical point of Ebola virus (EBOV)-induced immune subversion. The recent observation of late occurrence of EBOV-associated neurological disease highlights the importance to monitor the immuno-competence recovery at discharge as a tool to evaluate the risk of late sequelae associated with resumption of EBOV replication. Further studies are required to define the molecular mechanisms of EVD-driven activation/exhaustion and depletion of T-cells. PMID:27031961

  17. Longitudinal characterization of dysfunctional T cell-activation during human acute Ebola infection.

    PubMed

    Agrati, C; Castilletti, C; Casetti, R; Sacchi, A; Falasca, L; Turchi, F; Tumino, N; Bordoni, V; Cimini, E; Viola, D; Lalle, E; Bordi, L; Lanini, S; Martini, F; Nicastri, E; Petrosillo, N; Puro, V; Piacentini, M; Di Caro, A; Kobinger, G P; Zumla, A; Ippolito, G; Capobianchi, M R

    2016-03-31

    Data on immune responses during human Ebola virus disease (EVD) are scanty, due to limitations imposed by biosafety requirements and logistics. A sustained activation of T-cells was recently described but functional studies during the acute phase of human EVD are still missing. Aim of this work was to evaluate the kinetics and functionality of T-cell subsets, as well as the expression of activation, autophagy, apoptosis and exhaustion markers during the acute phase of EVD until recovery. Two EVD patients admitted to the Italian National Institute for Infectious Diseases, Lazzaro Spallanzani, were sampled sequentially from soon after symptom onset until recovery and analyzed by flow cytometry and ELISpot assay. An early and sustained decrease of CD4 T-cells was seen in both patients, with an inversion of the CD4/CD8 ratio that was reverted during the recovery period. In parallel with the CD4 T-cell depletion, a massive T-cell activation occurred and was associated with autophagic/apoptotic phenotype, enhanced expression of the exhaustion marker PD-1 and impaired IFN-gamma production. The immunological impairment was accompanied by EBV reactivation. The association of an early and sustained dysfunctional T-cell activation in parallel to an overall CD4 T-cell decline may represent a previously unknown critical point of Ebola virus (EBOV)-induced immune subversion. The recent observation of late occurrence of EBOV-associated neurological disease highlights the importance to monitor the immuno-competence recovery at discharge as a tool to evaluate the risk of late sequelae associated with resumption of EBOV replication. Further studies are required to define the molecular mechanisms of EVD-driven activation/exhaustion and depletion of T-cells.

  18. Dramatic increase in naïve T cell turnover is linked to loss of naïve T cells from old primates

    PubMed Central

    Čičin-Šain, Luka; Messaoudi, Ilhem; Park, Byung; Currier, Noreen; Planer, Shannon; Fischer, Miranda; Tackitt, Shane; Nikolich-Žugich, Dragana; Legasse, Alfred; Axthelm, Michael K.; Picker, Louis J.; Mori, Motomi; Nikolich-Žugich, Janko

    2007-01-01

    The loss of naïve T cells is a hallmark of immune aging. Although thymic involution is a primary driver of this naïve T cell loss, less is known about the contribution of other mechanisms to the depletion of naïve T cells in aging primates. We examined the role of homeostatic cycling and proliferative expansion in different T cell subsets of aging rhesus macaques (RM). BrdU incorporation and the expression of the G1-M marker Ki-67 were elevated in peripheral naïve CD4 and even more markedly in the naïve CD8 T cells of old, but not young adult, RM. Proliferating naïve cells did not accumulate in old animals. Rather, the relative size of the naïve CD8 T cell compartment correlated inversely to its proliferation rate. Likewise, T cell receptor diversity decreased in individuals with elevated naïve CD8 T cell proliferation. This apparent contradiction was explained by a significant increase in turnover concomitant with the naïve pool loss. The turnover increased exponentially when the naïve CD8 T cell pool decreased below 4% of total blood CD8 cells. These results link the shrinking naïve T cell pool with a dramatic increase in homeostatic turnover, which has the potential to exacerbate the progressive exhaustion of the naïve pool and constrict the T cell repertoire. Thus, homeostatic T cell proliferation exhibits temporal antagonistic pleiotropy, being beneficial to T cell maintenance in adulthood but detrimental to the long-term T cell maintenance in aging individuals. PMID:18056811

  19. Neutrophil Depletion during Toxoplasma gondii Infection Leads to Impaired Immunity and Lethal Systemic Pathology

    PubMed Central

    Bliss, Susan K.; Gavrilescu, L. Cristina; Alcaraz, Ana; Denkers, Eric Y.

    2001-01-01

    The immunomodulatory role of neutrophils during infection with Toxoplasma gondii was investigated. Monoclonal antibody-mediated depletion revealed that neutrophils are essential for survival during the first few days of infection. Moreover, neutrophil depletion was associated with a weaker type 1 immune response as measured by decreased levels of gamma interferon, interleukin-12 (IL-12) and tumor necrosis factor alpha. IL-10 was also decreased in depleted animals. Additionally, splenic populations of CD4+ T cells, CD8+ T cells, and NK1.1+ cells were decreased in depleted mice. Neutrophil-depleted mice exhibited lesions of greater severity in tissues examined and a greater parasite burden as determined by histopathology and reverse transcription-PCR. We conclude that neutrophils are critical near the time of infection because they influence the character of the immune response and control tachyzoite replication. PMID:11447166

  20. Effector CD4+ T cells recognize intravascular antigen presented by patrolling monocytes.

    PubMed

    Westhorpe, Clare L V; Norman, M Ursula; Hall, Pam; Snelgrove, Sarah L; Finsterbusch, Michaela; Li, Anqi; Lo, Camden; Tan, Zhe Hao; Li, Songhui; Nilsson, Susan K; Kitching, A Richard; Hickey, Michael J

    2018-02-21

    Although effector CD4 + T cells readily respond to antigen outside the vasculature, how they respond to intravascular antigens is unknown. Here we show the process of intravascular antigen recognition using intravital multiphoton microscopy of glomeruli. CD4 + T cells undergo intravascular migration within uninflamed glomeruli. Similarly, while MHCII is not expressed by intrinsic glomerular cells, intravascular MHCII-expressing immune cells patrol glomerular capillaries, interacting with CD4 + T cells. Following intravascular deposition of antigen in glomeruli, effector CD4 + T-cell responses, including NFAT1 nuclear translocation and decreased migration, are consistent with antigen recognition. Of the MHCII + immune cells adherent in glomerular capillaries, only monocytes are retained for prolonged durations. These cells can also induce T-cell proliferation in vitro. Moreover, monocyte depletion reduces CD4 + T-cell-dependent glomerular inflammation. These findings indicate that MHCII + monocytes patrolling the glomerular microvasculature can present intravascular antigen to CD4 + T cells within glomerular capillaries, leading to antigen-dependent inflammation.

  1. Natural killer T cells are required for the development of a superantigen-driven T helper type 2 immune response in mice

    PubMed Central

    Nomizo, Auro; Postol, Edilberto; de Alencar, Raquel; Cardillo, Fabíola; Mengel, José

    2005-01-01

    We show, here, that one single injection or weekly injections of staphylococcal enterotoxin B (SEB), starting in 1-day-old newborn mice, induced a powerful immune response with a T helper type 2 (Th2) pattern, as judged by the isotype and cytokine profile, with the production of large amounts of SEB-specific immunoglobulin G1 (IgG1), detectable levels of SEB-specific IgE and increased production of interleukin-4 by spleen cells. These protocols also induced an increase in the levels of total IgE in the serum. Memory of SEB was transferred to secondary recipients by using total spleen cells from primed animals. The secondary humoral response in transferred mice was diminished if spleen cells from SEB-treated mice were previously depleted of CD3+ or Vβ8+ T cells or NK1.1+ cells. In vivo depletion of NK1.1+ cells in adult mice resulted in a marked reduction in the SEB-specific antibody response in both the primary and secondary immune responses. Additionally, purified NK1.1+ T cells were able to perform SEB-specific helper B-cell actions in vitro and in vivo. These results suggest that NK1.1+ T cells are required for the full development of humoral immunological memory, whilst making neonatal tolerance to SEB unachievable. PMID:16162272

  2. Arp2 depletion inhibits sheet-like protrusions but not linear protrusions of fibroblasts and lymphocytes

    PubMed Central

    Nicholson-Dykstra, Susan M.; Higgs, Henry N.

    2009-01-01

    The Arp2/3 complex-mediated assembly and protrusion of a branched actin network at the leading edge occurs during cell migration, although some studies suggest it is not essential. In order to test the role of Arp2/3 complex in leading edge protrusion, Swiss 3T3 fibroblasts and Jurkat T cells were depleted of Arp2 and evaluated for defects in cell morphology and spreading efficiency. Arp2-depleted fibroblasts exhibit severe defects in formation of sheet-like protrusions at early time points of cell spreading, with sheet-like protrusions limited to regions along the length of linear protrusions. However, Arp2-depleted cells are able to spread fully after extended times. Similarly, Arp2-depleted Jurkat T lymphocytes exhibit defects in spreading on anti-CD3. Interphase Jurkats in suspension are covered with large ruffle structures, whereas mitotic Jurkats are covered by finger-like linear protrusions. Arp2-depleted Jurkats exhibit defects in ruffle assembly but not in assembly of mitotic linear protrusions. Similarly, Arp2-depletion has no effect on the highly dynamic linear protrusion of another suspended lymphocyte line. We conclude that Arp2/3 complex plays a significant role in assembly of sheet-like protrusions, especially during early stages of cell spreading, but is not required for assembly of a variety of linear actin-based protrusions. PMID:18720401

  3. Virus-Specific T Cells for the Immunocompromised Patient

    PubMed Central

    Houghtelin, Amy; Bollard, Catherine M.

    2017-01-01

    While progress has been made in the treatment of both hematologic cancers and solid tumors, chemorefractory or relapsed disease often portends a dismal prognosis, and salvage chemotherapy or radiation expose patients to intolerable toxicities and may not be effective. Hematopoietic stem cell transplant offers the promise of cure for many patients, and while mismatched, unrelated or haploidentical donors are increasingly available, the recipients are at higher risk of severe immunosuppression and immune dysregulation due to graft versus host disease. Viral infections remain a primary cause of severe morbidity and mortality in this patient population. Again, many therapeutic options for viral disease are toxic, may be ineffective or generate resistance, or fail to convey long-term protection. Adoptive cell therapy with virus-specific T cells (VSTs) is a targeted therapy that is efficacious and has minimal toxicity in immunocompromised patients with CMV and EBV infections in particular. Products have since been generated specific for multiple viral antigens (multi-VST), which are not only effective but also confer protection in 70–90% of recipients when used as prophylaxis. Notably, these products can be generated from either virus-naive or virus-experienced autologous or allogeneic sources, including partially matched HLA-matched third-party donors. Obstacles to effective VST treatment are donor availability and product generation time. Banking of third-party VST is an attractive way to overcome these constraints and provide products on an as-needed basis. Other developments include epitope discovery to broaden the number of viral antigens targets in a single product, the optimization of VST generation from naive donor sources, and the modification of VSTs to enhance persistence and efficacy in vivo. PMID:29075259

  4. Virus-Specific T Cells for the Immunocompromised Patient.

    PubMed

    Houghtelin, Amy; Bollard, Catherine M

    2017-01-01

    While progress has been made in the treatment of both hematologic cancers and solid tumors, chemorefractory or relapsed disease often portends a dismal prognosis, and salvage chemotherapy or radiation expose patients to intolerable toxicities and may not be effective. Hematopoietic stem cell transplant offers the promise of cure for many patients, and while mismatched, unrelated or haploidentical donors are increasingly available, the recipients are at higher risk of severe immunosuppression and immune dysregulation due to graft versus host disease. Viral infections remain a primary cause of severe morbidity and mortality in this patient population. Again, many therapeutic options for viral disease are toxic, may be ineffective or generate resistance, or fail to convey long-term protection. Adoptive cell therapy with virus-specific T cells (VSTs) is a targeted therapy that is efficacious and has minimal toxicity in immunocompromised patients with CMV and EBV infections in particular. Products have since been generated specific for multiple viral antigens (multi-VST), which are not only effective but also confer protection in 70-90% of recipients when used as prophylaxis. Notably, these products can be generated from either virus-naive or virus-experienced autologous or allogeneic sources, including partially matched HLA-matched third-party donors. Obstacles to effective VST treatment are donor availability and product generation time. Banking of third-party VST is an attractive way to overcome these constraints and provide products on an as-needed basis. Other developments include epitope discovery to broaden the number of viral antigens targets in a single product, the optimization of VST generation from naive donor sources, and the modification of VSTs to enhance persistence and efficacy in vivo .

  5. Armored CAR T cells enhance antitumor efficacy and overcome the tumor microenvironment.

    PubMed

    Yeku, Oladapo O; Purdon, Terence J; Koneru, Mythili; Spriggs, David; Brentjens, Renier J

    2017-09-05

    Chimeric antigen receptor (CAR) T cell therapy has shown limited efficacy for the management of solid tumor malignancies. In ovarian cancer, this is in part due to an immunosuppressive cytokine and cellular tumor microenvironment which suppresses adoptively transferred T cells. We engineered an armored CAR T cell capable of constitutive secretion of IL-12, and delineate the mechanisms via which these CAR T cells overcome a hostile tumor microenvironment. In this report, we demonstrate enhanced proliferation, decreased apoptosis and increased cytotoxicity in the presence of immunosuppressive ascites. In vivo, we show enhanced expansion and CAR T cell antitumor efficacy, culminating in improvement in survival in a syngeneic model of ovarian peritoneal carcinomatosis. Armored CAR T cells mediated depletion of tumor associated macrophages and resisted endogenous PD-L1-induced inhibition. These findings highlight the role of the inhibitory microenvironment and how CAR T cells can be further engineered to maintain efficacy.

  6. Formaldehyde fixation is detrimental to actin cables in glucose-depleted S. cerevisiae cells

    PubMed Central

    Vasicova, Pavla; Rinnerthaler, Mark; Haskova, Danusa; Novakova, Lenka; Malcova, Ivana; Breitenbach, Michael; Hasek, Jiri

    2016-01-01

    Actin filaments form cortical patches and emanating cables in fermenting cells of Saccharomyces cerevisiae. This pattern has been shown to be depolarized in glucose-depleted cells after formaldehyde fixation and staining with rhodamine-tagged phalloidin. Loss of actin cables in mother cells was remarkable. Here we extend our knowledge on actin in live glucose-depleted cells co-expressing the marker of actin patches (Abp1-RFP) with the marker of actin cables (Abp140-GFP). Glucose depletion resulted in appearance of actin patches also in mother cells. However, even after 80 min of glucose deprivation these cells showed a clear network of actin cables labeled with Abp140-GFP in contrast to previously published data. In live cells with a mitochondrial dysfunction (rho0 cells), glucose depletion resulted in almost immediate appearance of Abp140-GFP foci partially overlapping with Abp1-RFP patches in mother cells. Residual actin cables were clustered in patch-associated bundles. A similar overlapping “patchy” pattern of both actin markers was observed upon treatment of glucose-deprived rho+ cells with FCCP (the inhibitor of oxidative phosphorylation) and upon treatment with formaldehyde. While the formaldehyde-targeted process stays unknown, our results indicate that published data on yeast actin cytoskeleton obtained from glucose-depleted cells after fixation should be considered with caution. PMID:28357356

  7. Vaccination with live attenuated simian immunodeficiency virus causes dynamic changes in intestinal CD4+CCR5+ T cells

    PubMed Central

    2011-01-01

    Background Vaccination with live attenuated SIV can protect against detectable infection with wild-type virus. We have investigated whether target cell depletion contributes to the protection observed. Following vaccination with live attenuated SIV the frequency of intestinal CD4+CCR5+ T cells, an early target of wild-type SIV infection and destruction, was determined at days 3, 7, 10, 21 and 125 post inoculation. Results In naive controls, modest frequencies of intestinal CD4+CCR5+ T cells were predominantly found within the LPL TTrM-1 and IEL TTrM-2 subsets. At day 3, LPL and IEL CD4+CCR5+ TEM cells were dramatically increased whilst less differentiated subsets were greatly reduced, consistent with activation-induced maturation. CCR5 expression remained high at day 7, although there was a shift in subset balance from CD4+CCR5+ TEM to less differentiated TTrM-2 cells. This increase in intestinal CD4+CCR5+ T cells preceded the peak of SIV RNA plasma loads measured at day 10. Greater than 65.9% depletion of intestinal CD4+CCR5+ T cells followed at day 10, but overall CD4+ T cell homeostasis was maintained by increased CD4+CCR5- T cells. At days 21 and 125, high numbers of intestinal CD4+CCR5- naive TN cells were detected concurrent with greatly increased CD4+CCR5+ LPL TTrM-2 and IEL TEM cells at day 125, yet SIV RNA plasma loads remained low. Conclusions This increase in intestinal CD4+CCR5+ T cells, following vaccination with live attenuated SIV, does not correlate with target cell depletion as a mechanism of protection. Instead, increased intestinal CD4+CCR5+ T cells may correlate with or contribute to the protection conferred by vaccination with live attenuated SIV. PMID:21291552

  8. Mesenchymal Stromal Cells Disrupt mTOR-Signaling and Aerobic Glycolysis During T-Cell Activation.

    PubMed

    Böttcher, Martin; Hofmann, Andreas D; Bruns, Heiko; Haibach, Martina; Loschinski, Romy; Saul, Domenica; Mackensen, Andreas; Le Blanc, Katarina; Jitschin, Regina; Mougiakakos, Dimitrios

    2016-02-01

    Mesenchymal stromal cells (MSCs) possess numerous regenerative and immune modulating functions. Transplantation across histocompatibility barriers is feasible due to their hypo-immunogenicity. MSCs have emerged as promising tools for treating graft-versus-host disease following allogeneic stem cell transplantation. It is well established that their clinical efficacy is substantially attributed to fine-tuning of T-cell responses. At the same time, increasing evidence suggests that metabolic processes control T-cell function and fate. Here, we investigated the MSCs' impact on the metabolic framework of activated T-cells. In fact, MSCs led to mitigated mTOR signaling. This phenomenon was accompanied by a weaker glycolytic response (including glucose uptake, glycolytic rate, and upregulation of glycolytic machinery) toward T-cell activating stimuli. Notably, MSCs express indoleamine-2,3-dioxygenase (IDO), which mediates T-cell suppressive tryptophan catabolism. Our observations suggest that IDO-induced tryptophan depletion interferes with a tryptophan-sufficiency signal that promotes cellular mTOR activation. Despite an immediate suppression of T-cell responses, MSCs foster a metabolically quiescent T-cell phenotype characterized by reduced mTOR signaling and glycolysis, increased autophagy, and lower oxidative stress levels. In fact, those features have previously been shown to promote generation of long-lived memory cells and it remains to be elucidated how MSC-induced metabolic effects shape in vivo T-cell immunity. © 2015 AlphaMed Press.

  9. The role of missing killer cell immunoglobulin-like receptor ligands in T cell replete peripheral blood stem cell transplantation from HLA-identical siblings.

    PubMed

    Clausen, Johannes; Kircher, Brigitte; Auberger, Jutta; Schumacher, Petra; Ulmer, Hanno; Hetzenauer, Gabriele; Wolf, Dominik; Gastl, Günther; Nachbaur, David

    2010-02-01

    The contribution of natural killer (NK) cells to graft-versus-malignancy (GVM) effects following hematopoietic stem cell transplantation (HSCT) remains uncertain, particularly in the HLA-identical setting. A model considering missing HLA ligands to the donor's inhibitory killer cell immunoglobulin-like receptor (KIR), termed the missing KIR ligand model, has been established in T cell depleted bone marrow transplantation (BMT), but lacks validity in other cohorts with different treatment characteristics. We hypothesized that the impact of missing KIR ligands on relapse-free survival (RFS) and overall survival (OS) in T cell replete peripheral blood SCT (PBSCT) differs from that in the T cell depleted BMT setting, and retrospectively evaluated 100 consecutive, HLA-identical sibling transplantations for hematologic malignancies. In addition to KIR ligand status, we considered the donors' activating KIRs and grafted NK, T, and CD34(+) cell doses. Our findings demonstrate noninferiority for OS (P = .005) and RFS (P = .002) for the heterozygous HLA-C group KIR ligand status (C1/2; n = 47) compared with patients missing either C1 or C2 (n = 53). Similarly, OS (P = .031) and RFS (P = .034) of Bw4-positive patients was noninferior to that of patients missing a Bw4 ligand to KIR3DL1. By multivariate analysis, C1/2 heterozygous patients had a favorable risk ratio (RR) for relapse (RR = 0.28; P = .003), RFS (RR = 0.56; P = .046), and acute graft-versus-host disease grade II-IV (RR = 0.36; P = .05). Following reduced-intensity conditioning (RIC), but not standard-intensity conditioning, myeloablative (MA) transplantation, a grafted NK cell dose above the median (3.4 x 10(7)/kg) was associated with a lower risk of relapse (RR = 0.57; P = .003) and improved survival (RR = 0.78; P = .03). Overall, our findings support a role for NK alloreactivity in HLA-identical HSCT, but argue against a favorable impact of missing KIR ligands in the given setting. We conclude that the mechanism

  10. Cholesterol depletion in cell membranes of human airway epithelial cells suppresses MUC5AC gene expression.

    PubMed

    Song, Kee Jae; Kim, Na Hyun; Lee, Gi Bong; Kim, Ji Hoon; Kwon, Jin Ho; Kim, Kyung-Su

    2013-05-01

    If cholesterol in the cell membrane is depleted by treating cells with methyl-β-cyclodextrin (MβCD), the activities of transmembrane receptors are altered in a cell-specific and/or receptor-specific manner. The proinflammatory cytokines, IL-1β is potent inducers of MUC5AC mRNA and protein synthesis in human airway epithelial cells. Cells activated by IL-1β showed increased phosphorylation of extracellular signal regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK). Thus, we investigated the effects of cholesterol depletion on the expression of MUC5AC in human airway epithelial cells and whether these alterations to MUC5AC expression were related to MAPK activity. After NCI-H292 cells were pretreated with 1% MβCD before adding IL-1β for 24 hours, MUC5AC mRNA expression was determined by reverse transcription- polymerase chain reaction (RT-PCR) and real time-PCR. Cholesterol depletion by MβCD was measured by modified microenzymatic fluorescence assay and filipin staining. The phosphorylation of IL-1 receptor, ERK and p38 MAPK, was analyzed by western blot. Cholesterol in the cell membrane was significantly depleted by treatment with MβCD on cells. IL-1β-induced MUC5AC mRNA expression was decreased by MβCD and this decrease occurred IL-1-receptor- specifically. Moreover, we have shown that MβCD suppressed the activation of ERK1/2 and p38 MAPK in cells activated with IL-1β. This result suggests that MβCD-mediated suppression of IL-1β-induced MUC5AC mRNA operated via the ERK- and p38 MAPK-dependent pathway. Cholesterol depletion in NCI-H292 cell membrane may be considered an anti-hypersecretory method since it effectively inhibits mucus secretion of respiratory epithelial cells.

  11. The suppression of mitogen responses associated with resistance to experimental autoimmune encephalomyelitis requires adherent and T cells.

    PubMed

    Lyman, W D; Brosnan, C F; Kadish, A S; Raine, C S

    1984-05-01

    Resistance to experimental autoimmune encephalomyelitis (EAE) in Hartley guinea pigs has previously been reported to be associated with disease-specific antigen-induced suppression of mitogen responses in vitro. The present studies were initiated to investigate the requirement for different cell populations in this suppression. Intact and adherent-cell-depleted cultures of spleen cells from experimental and control animals were incubated with myelin basic protein (MBP), the major antigen of EAE, with the T-cell mitogen concanavalin A (Con A) alone or with Con A in the presence of MBP. In agreement with previous studies, MBP-induced suppression of the Con A response was observed only in cultures derived from resistant animals. In addition, it was observed that this suppression was abrogated by depletion of adherent cells. When cells from resistant and susceptible animals were mixed, suppression occurred only in the presence of nonadherent cells from resistant guinea pigs. Adherent cells from either resistant or susceptible animals functioned equally well. Cultures of purified E-rosette-forming cells (E+) from resistant animals (i.e., T cells) showed no suppression. Similarly, cells from these same animals which were depleted of E+ cells (i.e., non-T cells) did not demonstrate suppression in vitro. Upon reconstitution of spleen cell populations from resistant guinea pigs by mixing E+ and E- cells, suppression was restored. These experiments show that this model of suppression in vitro requires adherent cells as well as T cells and suggests that antigen-induced suppression of mitogen responses is dependent upon a cell-mediated immunologic mechanism.

  12. Activation of mouse liver natural killer cells and NK1.1(+) T cells by bacterial superantigen-primed Kupffer cells.

    PubMed

    Dobashi, H; Seki, S; Habu, Y; Ohkawa, T; Takeshita, S; Hiraide, H; Sekine, I

    1999-08-01

    Although bacterial superantigens have been well characterized as potent stimulators of T cells, their role in natural killer (NK)-type cells remains largely unknown. In the present study, we examined the effect of bacterial superantigens on mouse liver NK cells and NK1.1 Ag(+) (NK1(+)) T cells. C57BL/6 mice were intravenously injected with staphylococcal enterotoxin B (SEB) or streptococcal pyrogenic exotoxin A (SPE-A), and mononuclear cells (MNC) of various organs were obtained from mice 4 hours after being injected with superantigen. MNC were cultured for 48 hours, and interferon gamma (IFN-gamma) levels of supernatants were measured. The antitumor cytotoxicities of the liver and spleen MNC were also evaluated 24 hours after the mice were injected with superantigen. Liver MNC produced more IFN-gamma than did splenocytes, and peripheral blood and lung MNC did not produce any detectable IFN-gamma. In addition, liver MNC acquired a potent antitumor cytotoxicity by the SEB injection, and both NK cells and NK1(+)T cells but not cluster of differentiation (CD)8(+) T cells were responsible for the cytotoxicity as demonstrated by either in vivo or in vitro cell depletion experiments, and the NK-type cells were partly responsible for the increased serum IFN-gamma. Activation of liver NK-type cells was also supported by the fact that liver NK cells proportionally increased and NK1(+) T cells augmented their CD11a expressions after SEB injection. The pretreatment of mice with anti-IFN-gamma Ab and/or with anti-interleukin-12 (IL-12) Ab diminished the SEB-induced cytotoxicity of liver MNC. Furthermore, the in vivo depletion of Kupffer cells decreased the SEB-induced cytotoxicity of liver MNC. Consistent with these results, liver MNC stimulated with superantigens in the presence of Kupffer cells in vitro produced a greater amount of IFN-gamma than did the liver MNC without Kupffer cells or splenocytes. Our results suggest that bacterial superantigen-primed Kupffer cells

  13. Depletion of regulatory T cells leads to an exacerbation of delayed-type hypersensitivity arthritis in C57BL/6 mice that can be counteracted by IL-17 blockade

    PubMed Central

    Atkinson, Sara Marie; Hoffmann, Ute; Hamann, Alf; Bach, Emil; Danneskiold-Samsøe, Niels Banhos; Kristiansen, Karsten; Serikawa, Kyle; Fox, Brian; Kruse, Kim; Haase, Claus; Skov, Søren; Nansen, Anneline

    2016-01-01

    ABSTRACT Rodent models of arthritis have been extensively used in the elucidation of rheumatoid arthritis (RA) pathogenesis and are instrumental in the development of therapeutic strategies. Here we utilise delayed-type hypersensitivity arthritis (DTHA), a model in C57BL/6 mice affecting one paw with synchronised onset, 100% penetrance and low variation. We investigate the role of regulatory T cells (Tregs) in DTHA through selective depletion of Tregs and the role of IL-17 in connection with Treg depletion. Given the relevance of Tregs in RA, and the possibility of developing Treg-directed therapies, this approach could be relevant for advancing the understanding of Tregs in inflammatory arthritis. Selective depletion of Tregs was achieved using a Foxp3-DTR-eGFP mouse, which expresses the diphtheria toxin receptor (DTR) and enhanced green fluorescent protein (eGFP) under control of the Foxp3 gene. Anti-IL-17 monoclonal antibody (mAb) was used for IL-17 blockade. Numbers and activation of Tregs increased in the paw and its draining lymph node in DTHA, and depletion of Tregs resulted in exacerbation of disease as shown by increased paw swelling, increased infiltration of inflammatory cells, increased bone remodelling and increased production of inflammatory mediators, as well as increased production of anti-citrullinated protein antibodies. Anti-IL-17 mAb treatment demonstrated that IL-17 is important for disease severity in both the presence and absence of Tregs, and that IL-17 blockade is able to rescue mice from the exacerbated disease caused by Treg depletion and caused a reduction in RANKL, IL-6 and the number of neutrophils. We show that Tregs are important for the containment of inflammation and bone remodelling in DTHA. To our knowledge, this is the first study using the Foxp3-DTR-eGFP mouse on a C57BL/6 background for Treg depletion in an arthritis model, and we here demonstrate the usefulness of the approach to study the role of Tregs and IL-17 in arthritis

  14. T-cell suicide gene therapy prompts thymic renewal in adults after hematopoietic stem cell transplantation.

    PubMed

    Vago, Luca; Oliveira, Giacomo; Bondanza, Attilio; Noviello, Maddalena; Soldati, Corrado; Ghio, Domenico; Brigida, Immacolata; Greco, Raffaella; Lupo Stanghellini, Maria Teresa; Peccatori, Jacopo; Fracchia, Sergio; Del Fiacco, Matteo; Traversari, Catia; Aiuti, Alessandro; Del Maschio, Alessandro; Bordignon, Claudio; Ciceri, Fabio; Bonini, Chiara

    2012-08-30

    The genetic modification of T cells with a suicide gene grants a mechanism of control of adverse reactions, allowing safe infusion after partially incompatible hematopoietic stem cell transplantation (HSCT). In the TK007 clinical trial, 22 adults with hematologic malignancies experienced a rapid and sustained immune recovery after T cell-depleted HSCT and serial infusions of purified donor T cells expressing the HSV thymidine kinase suicide gene (TK+ cells). After a first wave of circulating TK+ cells, the majority of T cells supporting long-term immune reconstitution did not carry the suicide gene and displayed high numbers of naive lymphocytes, suggesting the thymus-dependent development of T cells, occurring only upon TK+ -cell engraftment. Accordingly, after the infusions, we documented an increase in circulating TCR excision circles and CD31+ recent thymic emigrants and a substantial expansion of the active thymic tissue as shown by chest tomography scans. Interestingly, a peak in the serum level of IL-7 was observed after each infusion of TK+ cells, anticipating the appearance of newly generated T cells. The results of the present study show that the infusion of genetically modified donor T cells after HSCT can drive the recovery of thymic activity in adults, leading to immune reconstitution.

  15. α4β7+ CD4+ Effector/Effector Memory T Cells Differentiate into Productively and Latently Infected Central Memory T Cells by Transforming Growth Factor β1 during HIV-1 Infection.

    PubMed

    Cheung, Ka-Wai; Wu, Tongjin; Ho, Sai Fan; Wong, Yik Chun; Liu, Li; Wang, Hui; Chen, Zhiwei

    2018-04-15

    HIV-1 transmission occurs mainly through mucosal tissues. During mucosal transmission, HIV-1 preferentially infects α 4 β 7 + gut-homing CCR7 - CD4 + effector/effector memory T cells (T EM ) and results in massive depletion of these cells and other subsets of T EM in gut-associated lymphoid tissues. However, besides being eliminated by HIV-1, the role of T EM during the early stage of infection remains inconclusive. Here, using in vitro -induced α 4 β 7 + gut-homing T EM (α 4 β 7 + T EM ), we found that α 4 β 7 + T EM differentiated into CCR7 + CD4 + central memory T cells (T CM ). This differentiation was HIV-1 independent but was inhibited by SB431542, a specific transforming growth factor β (TGF-β) receptor I kinase inhibitor. Consistently, T EM -to-T CM differentiation was observed in α 4 β 7 + T EM stimulated with TGF-β1 (TGF-β). The T CM properties of the TGF-β-induced T EM -derived T CM (α 4 β 7 + T CM ) were confirmed by their enhanced CCL19 chemotaxis and the downregulation of surface CCR7 upon T cell activation in vitro Importantly, the effect of TGF-β on T CM differentiation also held in T EM directly isolated from peripheral blood. To investigate the significance of the TGF-β-dependent T EM -to-T CM differentiation in HIV/AIDS pathogenesis, we observed that both productively and latently infected α 4 β 7 + T CM could differentiate from α 4 β 7 + T EM in the presence of TGF-β during HIV-1 infection. Collectively, this study not only provides a new insight for the plasticity of T EM but also suggests that the TGF-β-dependent T EM -to-T CM differentiation is a previously unrecognized mechanism for the formation of latently infected T CM after HIV-1 infection. IMPORTANCE HIV-1 is the causative agent of HIV/AIDS, which has led to millions of deaths in the past 30 years. Although the implementation of highly active antiretroviral therapy has remarkably reduced the HIV-1-related morbidity and mortality, HIV-1 is not eradicated in

  16. Force Spectrum Microscopy Using Mitochondrial Fluctuations of Control and ATP-Depleted Cells.

    PubMed

    Xu, Wenlong; Alizadeh, Elaheh; Prasad, Ashok

    2018-06-19

    A single-cell assay of active and passive intracellular mechanical properties of mammalian cells could give significant insight into cellular processes. Force spectrum microscopy (FSM) is one such technique, which combines the spontaneous motion of probe particles and the mechanical properties of the cytoskeleton measured by active microrheology using optical tweezers to determine the force spectrum of the cytoskeleton. A simpler and noninvasive method to perform FSM would be very useful, enabling its widespread adoption. Here, we develop an alternative method of FSM using measurement of the fluctuating motion of mitochondria. Mitochondria of the C3H-10T1/2 cell line were labeled and tracked using confocal microscopy. Mitochondrial probes were selected based on morphological characteristics, and their mean-square displacement, creep compliance, and distributions of directional change were measured. We found that the creep compliance of mitochondria resembles that of particles in viscoelastic media. However, comparisons of creep compliance between controls and cells treated with pharmacological agents showed that perturbations to the actomysoin network had surprisingly small effects on mitochondrial fluctuations, whereas microtubule disruption and ATP depletion led to a significantly decreased creep compliance. We used properties of the distribution of directional change to identify a regime of thermally dominated fluctuations in ATP-depleted cells, allowing us to estimate the viscoelastic parameters for a range of timescales. We then determined the force spectrum by combining these viscoelastic properties with measurements of spontaneous fluctuations tracked in control cells. Comparisons with previous measurements made using FSM revealed an excellent match. Copyright © 2018 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  17. Transcriptional Profiling of Experimental CD8+ Lymphocyte Depletion in Rhesus Macaques Infected with Simian Immunodeficiency Virus SIVmac239

    PubMed Central

    Bosinger, Steven E.; Jochems, Simon P.; Folkner, Kathryn A.; Hayes, Timothy L.; Klatt, Nichole R.

    2013-01-01

    CD8+ T cells inhibit virus replication in SIV-infected rhesus macaques. However, it is unclear to what extent the viral suppression mediated by CD8+ T cells reflects direct killing of infected cells as opposed to indirect, noncytolytic mechanisms. In this study, we used functional genomics to investigate noncytolytic mechanisms of in vivo viral suppression mediated by CD8+ lymphocytes. Eight chronically SIVmac239-infected rhesus macaques underwent CD8+ lymphocyte depletion, and RNA from whole blood was obtained prior to depletion, during the nadir of CD8+ cell depletion, and after CD8+ lymphocyte numbers had rebounded. We observed significant downregulation of the expression of genes encoding factors that can suppress SIV replication, including the CCR5-binding chemokine CCL5/RANTES and CCL4 and several members of the tripartite motif-containing (TRIM) family. Surprisingly, we also noted a strong, widespread downregulation of α- and θ-defensins with anti-HIV activity, which are not expressed by CD8+ T cells. After cessation of depleting antibody treatment, we observed induction of a transcriptional signature indicative of B lymphocyte activation. Validation experiments demonstrated that animals during this period had elevated levels of B cells coupled with higher expression of the proliferative marker Ki67, indicating that CD8+ depletion triggered a potent expansion of B cell numbers. Collectively, these data identify antiviral pathways perturbed by in vivo CD8+ T cell depletion that may contribute to noncytolytic control of SIV replication. PMID:23097439

  18. Comprehensive Approach for Identifying the T Cell Subset Origin of CD3 and CD28 Antibody-Activated Chimeric Antigen Receptor-Modified T Cells.

    PubMed

    Schmueck-Henneresse, Michael; Omer, Bilal; Shum, Thomas; Tashiro, Haruko; Mamonkin, Maksim; Lapteva, Natalia; Sharma, Sandhya; Rollins, Lisa; Dotti, Gianpietro; Reinke, Petra; Volk, Hans-Dieter; Rooney, Cliona M

    2017-07-01

    The outcome of therapy with chimeric Ag receptor (CAR)-modified T cells is strongly influenced by the subset origin of the infused T cells. However, because polyclonally activated T cells acquire a largely CD45RO + CCR7 - effector memory phenotype after expansion, regardless of subset origin, it is impossible to know which subsets contribute to the final T cell product. To determine the contribution of naive T cell, memory stem T cell, central memory T cell, effector memory T cell, and terminally differentiated effector T cell populations to the CD3 and CD28-activated CAR-modified T cells that we use for therapy, we followed the fate and function of individually sorted CAR-modified T cell subsets after activation with CD3 and CD28 Abs (CD3/28), transduction and culture alone, or after reconstitution into the relevant subset-depleted population. We show that all subsets are sensitive to CAR transduction, and each developed a distinct T cell functional profile during culture. Naive-derived T cells showed the greatest rate of proliferation but had more limited effector functions and reduced killing compared with memory-derived populations. When cultured in the presence of memory T cells, naive-derived T cells show increased differentiation, reduced effector cytokine production, and a reduced reproliferative response to CAR stimulation. CD3/28-activated T cells expanded in IL-7 and IL-15 produced greater expansion of memory stem T cells and central memory T cell-derived T cells compared with IL-2. Our strategy provides a powerful tool to elucidate the characteristics of CAR-modified T cells, regardless of the protocol used for expansion, reveals the functional properties of each expanded T cell subset, and paves the way for a more detailed evaluation of the effects of manufacturing changes on the subset contribution to in vitro-expanded T cells. Copyright © 2017 by The American Association of Immunologists, Inc.

  19. Foot-and-Mouth Disease Virus Can Induce a Specific and Rapid CD4+ T-Cell-Independent Neutralizing and Isotype Class-Switched Antibody Response in Naïve Cattle▿ †

    PubMed Central

    Juleff, Nicholas; Windsor, Miriam; Lefevre, Eric A.; Gubbins, Simon; Hamblin, Pip; Reid, Elizabeth; McLaughlin, Kerry; Beverley, Peter C. L.; Morrison, Ivan W.; Charleston, Bryan

    2009-01-01

    The role of T-lymphocyte subsets in recovery from foot-and-mouth disease virus (FMDV) infection in calves was investigated by administering subset-specific monoclonal antibodies. The depletion of circulating CD4+ or WC1+ γδ T cells was achieved for a period extending from before challenge to after resolution of viremia and peak clinical signs, whereas CD8+ cell depletion was only partial. The depletion of CD4+ cells was also confirmed by analysis of lymph node biopsy specimens 5 days postchallenge. Depletion with anti-WC1 and anti-CD8 antibodies had no effect on the kinetics of infection, clinical signs, and immune responses following FMDV infection. Three of the four CD4+ T-cell-depleted calves failed to generate an antibody response to the nonstructural polyprotein 3ABC but generated a neutralizing antibody response similar to that in the controls, including rapid isotype switching to immunoglobulin G antibody. We conclude that antibody responses to sites on the surface of the virus capsid are T cell independent, whereas those directed against the nonstructural proteins are T cell dependent. CD4 depletion was found to substantially inhibit antibody responses to the G-H peptide loop VP1135-156 on the viral capsid, indicating that responses to this particular site, which has a more mobile structure than other neutralizing sites on the virus capsid, are T cell dependent. The depletion of CD4+ T cells had no adverse effect on the magnitude or duration of clinical signs or clearance of virus from the circulation. Overall, we conclude that CD4+ T-cell-independent antibody responses play a major role in the resolution of foot-and-mouth disease in cattle. PMID:19176618

  20. HIV infection impairs Th1 and Th17 Mycobacterium tuberculosis-specific T cell responses

    PubMed Central

    Murray, Lyle W; Satti, Iman; Meyerowitz, Jodi; Jones, Matthew; Willberg, Christian B; Ussher, James E; Goedhals, Dominique; Hurst, Jacob; Phillips, Rodney E; McShane, Helen

    2018-01-01

    Background HIV-infected individuals have a higher risk of developing active tuberculosis than HIV-uninfected individuals, but the mechanisms underpinning this are unclear. We hypothesized that depletion of specific components of Mycobacterium tuberculosis (M.tb)-specific CD4+ and CD8+ T cell responses contributed to this increased risk. Methods M.tb-specific T cell responses in 147 HIV-infected and 44 HIV-uninfected control subjects in a TB-endemic setting in Bloemfontein, South Africa were evaluated. Using a whole-blood flow cytometry assay, we measured expression of IFNγ, TNFα, IL-2 and IL-17 in CD4+ and CD8+ T cells in response to M.tb antigens (PPD, ESAT-6/CFP-10 (EC) and DosR regulon-encoded α-crystallin (Rv2031c)). Results Fewer HIV-infected individuals had detectable CD4+ and CD8+ T cell responses to PPD and Rv2031c than HIV-uninfected subjects. M.tb-specific T cells showed distinct patterns of cytokine expression comprising both Th1 (CD4 and CD8) and Th17 (CD4) cytokines, the latter at highest frequency for Rv2031c. Th17 antigen-specific responses to all antigens tested were specifically impaired in HIV-infected individuals. Conclusions HIV-associated impairment of CD4+ and CD8+ M.tb-specific T cell responses is antigen-specific, particularly impacting responses to PPD and Rv2031c. Preferential depletion of Th17 cytokine-expressing CD4+ T cells suggests this T cell subset may be key to TB susceptibility in HIV-infected individuals. PMID:29546381

  1. HIV Infection in Uncircumcised Men Is Associated With Altered CD8 T-cell Function But Normal CD4 T-cell Numbers in the Foreskin.

    PubMed

    Prodger, Jessica L; Hirbod, Taha; Gray, Ronald; Kigozi, Godfrey; Nalugoda, Fred; Galiwango, Ronald; Reynolds, Steven J; Huibner, Sanja; Wawer, Maria J; Serwadda, David; Kaul, Rupert

    2014-04-15

    Human immunodeficiency virus (HIV)-infected (HIV+) men are more susceptible to sexually transmitted infections, and may be superinfected by HIV. We hypothesized that HIV induces immune alterations in the foreskin that may impact the subsequent acquisition/clearance of genital coinfections. Foreskin tissue and blood were obtained from 70 HIV-uninfected and 20 HIV+ men undergoing circumcision. T cells were characterized by flow cytometry, immunohistochemistry, and polymerase chain reaction. There was substantial influx of CD8 T-cells into the foreskins of HIV+ men (108.8 vs 23.1 cells/mm(2); P < .001); but foreskin CD4 T-cell density was unchanged (43.0 vs 33.7/mm(2); P = .67), despite substantial blood depletion (409.0 vs 877.8 cells/µL; P < .001). While frequencies of foreskin C-C chemokine receptor type 5(+) (CCR5(+)) T cells, T regulatory cells, and T-helper 17 cells were unaltered in HIV+ men, CD8 T-cell production of tumor necrosis factor α (TNFα) was decreased. HIV-specific CD8 T cells were present in the foreskins of HIV+ men, although their frequency and function was reduced compared to the blood. Foreskin CD4 T-cell density and CCR5 expression were not reduced during HIV infection, perhaps explaining susceptibility to HIV superinfection. Foreskin CD8 T-cell density was increased, but decreased production of TNFα may enhance susceptibility to genital coinfections in HIV+ men.

  2. Allogeneic hematopoietic stem cell transplantation in Primary Cutaneous T Cell Lymphoma.

    PubMed

    Cudillo, Laura; Cerretti, Raffaella; Picardi, Alessandra; Mariotti, Benedetta; De Angelis, Gottardo; Cantonetti, Maria; Postorino, Massimiliano; Ceresoli, Eleonora; De Santis, Giovanna; Nasso, Daniela; Pisani, Francesco; Scala, Enrico; Di Piazza, Fabio; Lanti, Alessandro

    2018-06-01

    In our retrospective study, 16 patients affected by advanced cutaneous T cell lymphoma (CTCL) underwent allogeneic hematopoietic stem cell transplantation (HSCT). Two patients (12.5%) were in complete remission (CR), nine (56.3%) in partial remission (PR), and five (31.2%) with active disease. The patients were transplanted from an HLA-identical (n = 7) from a mismatched (n = 1) or haploidentical (n = 1) sibling, from matched unrelated donor (n = 5), or from a single cord blood unit (n = 2). Conditioning regimen was standard myeloablative in 6 patients and at reduced intensity in 10. Seven patients died from non relapse mortality (NRM) and four patients relapsed or progressed, three of them achieved a second CR after donor lymphocyte infusion (DLI) or chemotherapy plus DLI. To date, with a median follow-up of 76 months (range 6-130), nine patients are alive, eight in CR, and one with active disease. Overall survival (OS) and disease-free survival (DFS) at 1 and 10 years are 61% (95% CI 40-91%) and 54% (95% CI 33-86%), 40% (95% CI 22-74%), and 34% (95% CI 16-68%), respectively. The time from diagnosis to transplant seems to influence negatively both OS (log-rank p < 0.04) and DFS (log-rank p < 0.05). Our results confirm on a long follow-up that CTCL appears particularly susceptible to the graft versus lymphoma (GVL) effect, so that allogeneic HSCT represents a possibility of cure for advanced CTCL. The timing of HSCT in the clinical course of disease remains an open issue.

  3. CD4+ T Cells Mediate Aspergillosis Vaccine Protection.

    PubMed

    Diaz-Arevalo, Diana; Kalkum, Markus

    2017-01-01

    Adaptive effector CD4 + T cells play essential roles in the defense against fungal infections, especially against invasive aspergillosis (IA). Such protective CD4 + T cells can be generated through immunization with specialized antifungal vaccines, as has been demonstrated for pulmonary Aspergillus fumigatus infections in mouse experiments. Adaptive transfer of fungal antigen-specific CD4 + T cells conferred protection onto non-immunized naive mice, an experimental approach that could potentially become a future treatment option for immunosuppressed IA patients, focusing on the ultimate goal to improve their otherwise dim chances for survival. Here, we describe the different techniques to analyze CD4 + T cell immune responses after immunization with a recombinant fungal protein. We present three major methods that are used to analyze the role of CD4 + T cells in protection against A. fumigatus challenge. They include (1) transplantation of CD4 + T cells from vaccinated mice into immunosuppressed naive mice, observing increasing protection of the cell recipients, (2) depletion of CD4 + T cells from vaccinated mice, which abolishes vaccine protection, and (3) T cell proliferation studies following stimulation with overlapping synthetic peptides or an intact protein vaccine. The latter can be used to validate immunization status and to identify protective T cell epitopes in vaccine antigens. In the methods detailed here, we used versions of the well-studied Asp f3 protein expressed in a bacterial host, either as the intact full length protein or its N-terminally truncated version, comprised of residues 15-168. However, these methods are generally applicable and can well be adapted to study other protein-based subunit vaccines.

  4. CPI-613 and Bendamustine Hydrochloride in Treating Patients With Relapsed or Refractory T-Cell Non-Hodgkin Lymphoma or Hodgkin Lymphoma

    ClinicalTrials.gov

    2017-12-20

    Adult Lymphocyte Depletion Hodgkin Lymphoma; Adult Lymphocyte Predominant Hodgkin Lymphoma; Adult Mixed Cellularity Hodgkin Lymphoma; Adult Nasal Type Extranodal NK/T-cell Lymphoma; Adult Nodular Sclerosis Hodgkin Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Hepatosplenic T-cell Lymphoma; Noncutaneous Extranodal Lymphoma; Peripheral T-cell Lymphoma; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; T-cell Adult Acute Lymphoblastic Leukemia; T-cell Large Granular Lymphocyte Leukemia

  5. Donor CD4+ Foxp3+ regulatory T cells are necessary for posttransplantation cyclophosphamide-mediated protection against GVHD in mice

    PubMed Central

    Ganguly, Sudipto; Ross, Duncan B.; Panoskaltsis-Mortari, Angela; Kanakry, Christopher G.; Blazar, Bruce R.; Levy, Robert B.

    2014-01-01

    Posttransplantation cyclophosphamide (PTCy) is an effective prophylaxis against graft-versus-host disease (GVHD). However, it is unknown whether PTCy works singularly by eliminating alloreactive T cells via DNA alkylation or also by restoring the conventional (Tcon)/regulatory (Treg) T-cell balance. We studied the role of Tregs in PTCy-mediated GVHD prophylaxis in murine models of allogeneic blood or marrow transplantation (alloBMT). In 2 distinct MHC-matched alloBMT models, infusing Treg-depleted allografts abrogated the GVHD-prophylactic activity of PTCy. Using allografts in which Foxp3+ Tregs could be selectively depleted in vivo, either pre- or post-PTCy ablation of donor thymus–derived Tregs (tTregs) abolished PTCy protection against GVHD. PTCy treatment was associated with relative preservation of donor Tregs. Experiments using combinations of Foxp3– Tcons and Foxp3+ Tregs sorted from different Foxp3 reporter mice indicated that donor Treg persistence after PTCy treatment was predominantly caused by survival of functional tTregs that retained Treg-specific demethylation and also induction of peripherally derived Tregs. Finally, adoptive transfer of tTregs retrieved from PTCy-treated chimeras rescued PTCy-treated, Treg-depleted recipients from lethal GVHD. Our findings indicate that PTCy-mediated protection against GVHD is not singularly dependent on depletion of donor alloreactive T cells but also requires rapidly recovering donor Tregs to initiate and maintain alloimmune regulation. PMID:25139358

  6. Critical role of dendritic cells in T cell retention in the interfollicular region of Peyer's patches.

    PubMed

    Obata, Takashi; Shibata, Naoko; Goto, Yoshiyuki; Ishikawa, Izumi; Sato, Shintaro; Kunisawa, Jun; Kiyono, Hiroshi

    2013-07-15

    Peyer's patches (PPs) simultaneously initiate active and quiescent immune responses in the gut. The immunological function is achieved by the rigid regulation of cell distribution and trafficking, but how the cell distribution is maintained remains to be elucidated. In this study, we show that binding of stromal cell-derived lymphoid chemokines to conventional dendritic cells (cDCs) is essential for the retention of naive CD4(+) T cells in the interfollicular region (IFR) of PPs. Transitory depletion of CD11c(high) cDCs in mice rapidly impaired the IFR structure in the PPs without affecting B cell follicles or germinal centers, lymphoid chemokine production from stromal cells, or the immigration of naive T cells into the IFRs of PPs. The cDC-orchestrated retention of naive T cells was mediated by heparinase-sensitive molecules that were expressed on cDCs and bound the lymphoid chemokine CCL21 produced from stromal cells. These data collectively reveal that interactions among cDCs, stromal cells, and naive T cells are necessary for the formation of IFRs in the PPs.

  7. How nonuniform contact profiles of T cell receptors modulate thymic selection outcomes

    NASA Astrophysics Data System (ADS)

    Chen, Hanrong; Chakraborty, Arup K.; Kardar, Mehran

    2018-03-01

    T cell receptors (TCRs) bind foreign or self-peptides attached to major histocompatibility complex (MHC) molecules, and the strength of this interaction determines T cell activation. Optimizing the ability of T cells to recognize a diversity of foreign peptides yet be tolerant of self-peptides is crucial for the adaptive immune system to properly function. This is achieved by selection of T cells in the thymus, where immature T cells expressing unique, stochastically generated TCRs interact with a large number of self-peptide-MHC; if a TCR does not bind strongly enough to any self-peptide-MHC, or too strongly with at least one self-peptide-MHC, the T cell dies. Past theoretical work cast thymic selection as an extreme value problem and characterized the statistical enrichment or depletion of amino acids in the postselection TCR repertoire, showing how T cells are selected to be able to specifically recognize peptides derived from diverse pathogens yet have limited self-reactivity. Here, we investigate how the diversity of the postselection TCR repertoire is modified when TCRs make nonuniform contacts with peptide-MHC. Specifically, we were motivated by recent experiments showing that amino acids at certain positions of a TCR sequence have large effects on thymic selection outcomes, and crystal structure data that reveal a nonuniform contact profile between a TCR and its peptide-MHC ligand. Using a representative TCR contact profile as an illustration, we show via simulations that the statistical enrichment or depletion of amino acids now varies by position according to the contact profile, and, importantly, it depends on the implementation of nonuniform contacts during thymic selection. We explain these nontrivial results analytically. Our study has implications for understanding the selection forces that shape the functionality of the postselection TCR repertoire.

  8. Impact of thiamine deficiency on T-cell dependent and T-cell independent antibody production in lake trout

    USGS Publications Warehouse

    Ottinger, Christopher A.; Honeyfield, Dale C.; Densmore, Christine L.; Iwanowicz, Luke R.

    2012-01-01

    Lake trout Salvelinus namaycush on thiamine-replete and thiamine-depleted diets were evaluated for the effects of thiamine status on in vivo responses to the T-dependent antigen trinitophenol (TNP)-keyhole limpet hemocyanin (TNP-KLH), the T-independent antigen trinitrophenol-lipolysaccaharide (TNP-LPS), or Dulbecco's phosphate-buffered saline (DPBS; negative control fish). Plasma antibody concentrations were evaluated for possible differences in total anti-TNP activity as well as differences in response kinetics. Associations between anti-TNP activity and muscle and liver thiamine concentrations as well as ratios of muscle-to-liver thiamine to anti-TNP activity were also examined. Thiamine-depleted lake trout that were injected with TNP-LPS exhibited significantly more anti-TNP activity than thiamine-replete fish. The depleted fish injected with TNP-LPS also exhibited significantly different response kinetics relative to thiamine-replete lake trout. No differences in activity or kinetics were observed between the thiamine-replete and -depleted fish injected with TNP-KLH or in the DPBS negative controls. Anti-TNP activity in thiamine-depleted lake trout injected with TNP-KLH was positively associated with muscle thiamine pyrophosphate (thiamine diphosphate; TPP) concentration. A negative association was observed between the ratio of muscle-to-liver TPP and T-independent responses. No significant associations between anti-TNP activity and tissue thiamine concentration were observed in the thiamine-replete fish. We demonstrated that thiamine deficiency leads to alterations in both T-dependent and T-independent immune responses in lake trout.

  9. Impact of thiamine deficiency on T-cell dependent and T-cell independent antibody production in lake trout.

    PubMed

    Ottinger, Christopher A; Honeyfield, Dale C; Densmore, Christine L; Iwanowicz, Luke R

    2012-12-01

    Lake trout Salvelinus namaycush on thiamine-replete and thiamine-depleted diets were evaluated for the effects of thiamine status on in vivo responses to the T-dependent antigen trinitophenol (TNP)-keyhole limpet hemocyanin (TNP-KLH), the T-independent antigen trinitrophenol-lipolysaccaharide (TNP-LPS), or Dulbecco's phosphate-buffered saline (DPBS; negative control fish). Plasma antibody concentrations were evaluated for possible differences in total anti-TNP activity as well as differences in response kinetics. Associations between anti-TNP activity and muscle and liver thiamine concentrations as well as ratios of muscle-to-liver thiamine to anti-TNP activity were also examined. Thiamine-depleted lake trout that were injected with TNP-LPS exhibited significantly more anti-TNP activity than thiamine-replete fish. The depleted fish injected with TNP-LPS also exhibited significantly different response kinetics relative to thiamine-replete lake trout. No differences in activity or kinetics were observed between the thiamine-replete and -depleted fish injected with TNP-KLH or in the DPBS negative controls. Anti-TNP activity in thiamine-depleted lake trout injected with TNP-KLH was positively associated with muscle thiamine pyrophosphate (thiamine diphosphate; TPP) concentration. A negative association was observed between the ratio of muscle-to-liver TPP and T-independent responses. No significant associations between anti-TNP activity and tissue thiamine concentration were observed in the thiamine-replete fish. We demonstrated that thiamine deficiency leads to alterations in both T-dependent and T-independent immune responses in lake trout.

  10. Cation depletion by the sodium pump in red cells with pathologic cation leaks. Sickle cells and xerocytes.

    PubMed Central

    Joiner, C H; Platt, O S; Lux, S E

    1986-01-01

    The mechanism by which sickle cells and xerocytic red cells become depleted of cations in vivo has not been identified previously. Both types of cells exhibit elevated permeabilities to sodium and potassium, in the case of sickle cells, when deoxygenated. The ouabain-insensitive fluxes of sodium and potassium were equivalent, however, in both cell types under these conditions. When incubated 18 hours in vitro, sickle cells lost cations but only when deoxygenated. This cation depletion was blocked by ouabain, removal of external potassium, or pretreatment with 4,4'-diisothiocyanostilbene-2,2'-disulfonate, which blocks the increase in cation permeability induced by deoxygenation. The loss of cation exhibited by oxygenated xerocytes similarly incubated was also blocked by ouabain. These data support the hypothesis that the elevated "passive" cation fluxes of xerocytes and deoxygenated sickle cells are not directly responsible for cation depletion of these cells; rather, these pathologic leaks interact with the sodium pump to produce a net loss of cellular cation. PMID:2430999

  11. Cation depletion by the sodium pump in red cells with pathologic cation leaks. Sickle cells and xerocytes.

    PubMed

    Joiner, C H; Platt, O S; Lux, S E

    1986-12-01

    The mechanism by which sickle cells and xerocytic red cells become depleted of cations in vivo has not been identified previously. Both types of cells exhibit elevated permeabilities to sodium and potassium, in the case of sickle cells, when deoxygenated. The ouabain-insensitive fluxes of sodium and potassium were equivalent, however, in both cell types under these conditions. When incubated 18 hours in vitro, sickle cells lost cations but only when deoxygenated. This cation depletion was blocked by ouabain, removal of external potassium, or pretreatment with 4,4'-diisothiocyanostilbene-2,2'-disulfonate, which blocks the increase in cation permeability induced by deoxygenation. The loss of cation exhibited by oxygenated xerocytes similarly incubated was also blocked by ouabain. These data support the hypothesis that the elevated "passive" cation fluxes of xerocytes and deoxygenated sickle cells are not directly responsible for cation depletion of these cells; rather, these pathologic leaks interact with the sodium pump to produce a net loss of cellular cation.

  12. Engineering and biological characterization of VB6-845, an anti-EpCAM immunotoxin containing a T-cell epitope-depleted variant of the plant toxin bouganin.

    PubMed

    Cizeau, Jeannick; Grenkow, Danielle M; Brown, Jennifer G; Entwistle, Joycelyn; MacDonald, Glen C

    2009-01-01

    The clinical development of immunotoxins in the treatment of solid tumors has been impeded in part, by the induction of an immune response directed primarily against the toxin moiety. Bouganin, a type I ribosome inactivating protein isolated from the leaf of Bougainvillea spectabilis Willd, was mutated to remove the T-cell epitopes while preserving the biological activity of the wild-type molecule. The T-cell epitope-depleted variant of bouganin (de-bouganin) was genetically linked to an anti-epithelial cell adhesion molecule (EpCAM) Fab moiety via a peptidic linker containing a furin proteolytic site to create the fusion construct VB6-845. To determine the optimal construct design for VB6-845, several dicistronic units where de-bouganin was genetically linked to either the N-terminal or C-terminal of either the heavy or light chain were engineered. Only the C-terminal variants expressed the full-length molecule. An in vitro assessment of the biological activity of VB6-845 showed that it bound and selectively killed EpCAM-positive cell lines with a greater potency than many commonly used chemotherapeutic agents. In vivo efficacy was demonstrated using an EpCAM-positive human tumor xenograft model in SCID mice with the majority of the mice treated being tumor free at the end of the study.

  13. GammadeltaT cells positively regulate contact sensitivity (CS) reaction via modulation of INF-gamma, IL-12 and TNF-alpha production.

    PubMed

    Strzepa, Anna; Majewska-Szczepanik, Monika; Szczepanik, Marian

    2013-01-01

    The gammadeltaT cells were identified as positive as well as negative regulators of immune responses. They take part in pathogen clearance, modulation of innate and adaptive immunity as well as in healing and tissue maintenance. The course of many pathological conditions such as collagen induced arthritis (CIA), experimental autoimmune encephalomyelitis (EAE) and airway hyperresponsiveness is positively regulated by gammadeltaT cells. It was shown previously that contact sensitivity (CS), an example of antigen-specific cell-mediated immune response, is also positively regulated by gammadeltaT cells. The current work confirmed the regulatory function of gammadeltaT cells in CS response as their depletion with anti-TCRdelta monoclonal antibody and complement significantly decreased adoptive transfer of the CS reaction. In vitro study showed that removal of gammadeltaT cells with magnetic beads significantly decreased the production of the proinflammatory cytokines IFN-gamma, IL-12 and TNF-alpha. Reconstitution of gammadeltaT-depleted cells with gammadeltaT-enriched cells restored cytokine production, proving the reversibility of the investigated process. In summary, gammadeltaT cells positively regulate the CS reaction via modulation of proinflammatory cytokine production.

  14. Glutathione-mediated detoxification of halobenzoquinone drinking water disinfection byproducts in T24 cells.

    PubMed

    Li, Jinhua; Wang, Wei; Zhang, Hongquan; Le, X Chris; Li, Xing-Fang

    2014-10-01

    Halobenzoquinones (HBQs) are a new class of drinking water disinfection byproducts (DBPs) and are capable of producing reactive oxygen species and causing oxidative damage to proteins and DNA in T24 human bladder carcinoma cells. However, the exact mechanism of the cytotoxicity of HBQs is unknown. Here, we investigated the role of glutathione (GSH) and GSH-related enzymes including glutathione S-transferase (GST) and glutathione peroxidase (GPx) in defense against HBQ-induced cytotoxicity in T24 cells. The HBQs are 2,6-dichloro-1,4-benzoquinone (DCBQ), 2,6-dichloro-3-methyl-1,4-benzoquinone (DCMBQ), 2,3,6-trichloro-1,4-benzoquinone (TriCBQ), and 2,6-dibromobenzoquinone (DBBQ). We found that depletion of cellular GSH could sensitize cells to HBQs and extracellular GSH supplementation could attenuate HBQ-induced cytotoxicity. HBQs caused significant cellular GSH depletion and increased cellular GST activities in a concentration-dependent manner. Our mass spectrometry study confirms that HBQs can conjugate with GSH, explaining in part the mechanism of GSH depletion by HBQs. The effects of HBQs on GPx activity are compound dependent; DCMBQ and DBBQ decrease cellular GPx activities, whereas DCBQ and TriCBQ have no significant effects. Pearson correlation analysis shows that the cellular GSH level is inversely correlated with ROS production and cellular GST activity in HBQ-treated cells. These results support a GSH and GSH-related enzyme-mediated detoxification mechanism of HBQs in T24 cells. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  15. Persistent Simian Immunodeficiency Virus Infection Causes Ultimate Depletion of Follicular Th Cells in AIDS.

    PubMed

    Xu, Huanbin; Wang, Xiaolei; Malam, Naomi; Lackner, Andrew A; Veazey, Ronald S

    2015-11-01

    CD4(+) T follicular helper (Tfh) cells are critical for the generation of humoral immune responses to pathogenic infections, providing help for B cell development, survival, and affinity maturation of Abs. Although CD4(+) Tfh cells are reported to accumulate in HIV or SIV infection, we found that germinal center Tfh cells, defined in this study as CXCR5(+)PD-1(HIGH)CD4(+) T cells, did not consistently accumulate in chronically SIV-infected rhesus macaques compared with those infected with less pathogenic simian HIV, vaccinated and SIVmac-challenged, or SIVmac-infected Mamu-A*01(+) macaques, all of which are associated with some control of virus replication and slower disease progression. Interestingly, CXCR5(+)PD-1(HIGH) Tfh cells in lymphoid tissues were eventually depleted in macaques with AIDS compared with the other cohorts. Chronic activation and proliferation of CXCR5(+)PD-1(HIGH) Tfh were increased, but PD-L2 expression was downregulated on B cells, possibly resulting in germinal center Tfh cell apoptosis. Together, these findings suggest that changes in CXCR5(+)PD-1(HIGH) Tfh cells in lymph nodes correlate with immune control during infection, and their loss or dysregulation contribute to impairment of B cell responses and progression to AIDS. Copyright © 2015 by The American Association of Immunologists, Inc.

  16. T cell-macrophage interaction in arginase-mediated resistance to herpes simplex virus.

    PubMed

    Bonina, L; Nash, A A; Arena, A; Leung, K N; Wildy, P

    1984-09-01

    Peritoneal macrophages activated by-products derived from a herpes simplex virus-specific helper T cell clone were used to investigate intrinsic and extrinsic resistance mechanisms to herpes simplex virus type 1 infection in vitro. T cell-activated macrophages produced fewer infective centres, indicating enhanced intrinsic resistance, and markedly reduced the growth of virus in a permissive cell line. The reduction in virus growth correlated with the depletion of arginine in the support medium, presumably resulting from increased arginase production by activated macrophages. The significance of these findings for antiviral immunity in vivo is discussed.

  17. Single-cell analysis of lymphokine imbalance in asymptomatic HIV-1 infection: evidence for a major alteration within the CD8+ T cell subset

    PubMed Central

    Sousa, A E; Victorino, R M M

    1998-01-01

    In this study we investigated at single-cell level by flow cytometry the potential of T cell cytokine production in asymptomatic HIV-1-infected subjects with > 200 CD4 counts and possible correlation with T helper cell depletion and viral load. Mitogen-stimulated peripheral blood mononuclear cells from 32 HIV-1+ patients and 16 healthy subjects were intracytoplasmically stained for IL-2, interferon-gamma (IFN-γ), IL-4 or IL-10, and the frequency of cytokine-producing cells was assessed in total T cells, CD4, CD8 and CD45RO subsets as well as in CD69+CD3+ gated lymphocytes. HIV-1+ patients, irrespective of their degree of CD4 depletion, exhibited a major increase in IFN-γ+ CD8 T cells, largely due to CD28− cells, as well as a decrease in the capacity of CD8 T cells to produce IL-2. Patients with > 500 CD4 counts showed a diminished frequency of IL-4 expression in CD4 T cells and a negative correlation was found between this parameter and the ex vivo CD4 counts in the 32 patients. Analysis of patients stratified according to viral load revealed a significantly higher proportion of IL-2-producing CD4 cells in the group with < 5000 RNA copies/ml. In short, using single-cell analysis and an antigen-presenting cell-independent stimulus, we have not been able to find any significant cytokine imbalances in the CD4 subset, suggesting that the well described T helper defects are not due to intrinsic alterations in the potential of CD4 T cells to produce cytokines. On the other hand, the major disturbances in the CD8 T lymphocytes agree with the marked activation and possible replicative senescence of CD8 T cells and emphasize the role of this subset in HIV immunopathogenesis. PMID:9649194

  18. Differential effects of HIV transmission from monocyte-derived dendritic cells vs. monocytes to IL-17+CD4+ T cells

    PubMed Central

    Mitsuki, Yu-ya; Tuen, Michael; Hioe, Catarina E.

    2017-01-01

    HIV infection leads to CD4 helper T cell (Th) loss, but not all Th cells are equally depleted. The contribution of other immune cells in the Th depletion also remains unclear. This study investigates HIV transmission from monocyte-derived dendritic cells (MDDCs) vs. monocytes to Th17 and Th1 cells using an allogeneic coculture model. The addition of HIV to MDDCs increased the expression of the negative regulatory molecule PD-L1 and decreased the expression of the activation markers HLA-DR and CD86, whereas the virus up-regulated HLA-DR and CD86, but not PD-L1, on monocytes. Coculturing of CD4+ T cells with MDDCs pretreated with HIV led to the decline of Th17, but not Th1, responses. In contrast, pretreatment of monocytes with HIV increased Th17 without affecting Th1 responses. The enhanced Th17 responses in the cocultures with HIV-treated monocytes were also accompanied by high numbers of virus-infected CD4+ T cells. The Th17 expansion arose from memory CD4+ T cells with minimal contribution from naïve CD4+ T cells. The Th17-enhancing activity was mediated by the HIV envelope and did not require productive virus infection. Comparison of MDDCs and monocytes further showed that, although HIV-treated MDDCs reduced Th proliferation and increased the activation of the apoptosis mediator caspase-3, HIV-treated monocytes enhanced Th proliferation without increasing the active caspase-3 levels. This study indicates the potential role of distinct myeloid cell populations in shaping Th17 responses during HIV infection. PMID:27531931

  19. Human skin is protected by four functionally and phenotypically discrete populations of resident and recirculating memory T cells.

    PubMed

    Watanabe, Rei; Gehad, Ahmed; Yang, Chao; Scott, Laura L; Teague, Jessica E; Schlapbach, Christoph; Elco, Christopher P; Huang, Victor; Matos, Tiago R; Kupper, Thomas S; Clark, Rachael A

    2015-03-18

    The skin of an adult human contains about 20 billion memory T cells. Epithelial barrier tissues are infiltrated by a combination of resident and recirculating T cells in mice, but the relative proportions and functional activities of resident versus recirculating T cells have not been evaluated in human skin. We discriminated resident from recirculating T cells in human-engrafted mice and lymphoma patients using alemtuzumab, a medication that depletes recirculating T cells from skin, and then analyzed these T cell populations in healthy human skin. All nonrecirculating resident memory T cells (TRM) expressed CD69, but most were CD4(+), CD103(-), and located in the dermis, in contrast to studies in mice. Both CD4(+) and CD8(+) CD103(+) TRM were enriched in the epidermis, had potent effector functions, and had a limited proliferative capacity compared to CD103(-) TRM. TRM of both types had more potent effector functions than recirculating T cells. We observed two distinct populations of recirculating T cells, CCR7(+)/L-selectin(+) central memory T cells (TCM) and CCR7(+)/L-selectin(-) T cells, which we term migratory memory T cells (TMM). Circulating skin-tropic TMM were intermediate in cytokine production between TCM and effector memory T cells. In patients with cutaneous T cell lymphoma, malignant TCM and TMM induced distinct inflammatory skin lesions, and TMM were depleted more slowly from skin after alemtuzumab, suggesting that TMM may recirculate more slowly. In summary, human skin is protected by four functionally distinct populations of T cells, two resident and two recirculating, with differing territories of migration and distinct functional activities. Copyright © 2015, American Association for the Advancement of Science.

  20. Chronic Exposure to Type-I IFN under Lymphopenic Conditions Alters CD4 T Cell Homeostasis

    PubMed Central

    Le Saout, Cecile; Hasley, Rebecca B.; Imamichi, Hiromi; Tcheung, Lueng; Hu, Zonghui; Luckey, Megan A.; Park, Jung-Hyun; Durum, Scott K.; Smith, Mindy; Rupert, Adam W.; Sneller, Michael C.; Lane, H. Clifford; Catalfamo, Marta

    2014-01-01

    HIV infection and the associated chronic immune activation alter T cell homeostasis leading to CD4 T cell depletion and CD8 T cell expansion. The mechanisms behind these outcomes are not totally defined and only partially explained by the direct cytopathic effect of the virus. In this manuscript, we addressed the impact of lymphopenia and chronic exposure to IFN-α on T cell homeostasis. In a lymphopenic murine model, this interaction led to decreased CD4 counts and CD8 T cell expansion in association with an increase in the Signal Transducer and Activator of Transcription 1 (STAT1) levels resulting in enhanced CD4 T cell responsiveness to IFN-α. Thus, in the setting of HIV infection, chronic stimulation of this pathway could be detrimental for CD4 T cell homeostasis. PMID:24603698

  1. T-cell and natural killer cell therapies for hematologic malignancies after hematopoietic stem cell transplantation: enhancing the graft-versus-leukemia effect

    PubMed Central

    Cruz, C. Russell; Bollard, Catherine M.

    2015-01-01

    Hematopoietic stem cell transplantation has revolutionized the treatment of hematologic malignancies, but infection, graft-versus-host disease and relapse are still important problems. Calcineurin inhibitors, T-cell depletion strategies, and immunomodulators have helped to prevent graft-versus-host disease, but have a negative impact on the graft-versus-leukemia effect. T cells and natural killer cells are both thought to be important in the graft-versus-leukemia effect, and both cell types are amenable to ex vivo manipulation and clinical manufacture, making them versatile immunotherapeutics. We provide an overview of these immunotherapeutic strategies following hematopoietic stem cell transplantation, with discussions centered on natural killer and T-cell biology. We discuss the contributions of each cell type to graft-versus-leukemia effects, as well as the current research directions in the field as related to adoptive cell therapy after hematopoietic stem cell transplantation. PMID:26034113

  2. Myeloid cells in peripheral blood mononuclear cell concentrates inhibit the expansion of chimeric antigen receptor T cells.

    PubMed

    Stroncek, David F; Ren, Jiaqiang; Lee, Daniel W; Tran, Minh; Frodigh, Sue Ellen; Sabatino, Marianna; Khuu, Hanh; Merchant, Melinda S; Mackall, Crystal L

    2016-07-01

    Autologous chimeric antigen receptor (CAR) T-cell therapies have shown promising clinical outcomes, but T-cell yields have been variable. CD19- and GD2-CAR T-cell manufacturing records were reviewed to identify sources of variability. CD19-CAR T cells were used to treat 43 patients with acute lymphocytic leukemia or lymphoma and GD2-CAR T cells to treat eight patients with osteosarcoma and three with neuroblastoma. Both types of CAR T cells were manufactured using autologous peripheral blood mononuclear cells (PBMC) concentrates and anti-CD3/CD28 beads for T-cell enrichment and simulation. A comparison of the first 6 GD2- and the first 22 CD19-CAR T-cell products manufactured revealed that GD2-CAR T-cell products contained fewer transduced cells than CD19-CAR T-cell products (147 ± 102 × 10(6) vs 1502 ± 1066 × 10(6); P = 0.0059), and their PBMC concentrates contained more monocytes (31.4 ± 12.4% vs 18.5 ± 13.7%; P = 0.019). Among the first 28 CD19-CAR T-cell products manufactured, four had poor expansion yielding less than 1 × 10(6) transduced T cells per kilogram. When PBMC concentrates from these four patients were compared with the 24 others, PBMC concentrates of poorly expanding products contained greater quantities of monocytes (39.8 ± 12.9% vs. 15.3 ± 10.8%, P = 0.0014). Among the patients whose CD19-CAR T cells expanded poorly, manufacturing for two patients was repeated using cryopreserved PBMC concentrates but incorporating a monocyte depleting plastic adherence step, and an adequate dose of CAR T cells was produced for both patients. Variability in CAR T-cell expansion is due, at least in part, to the contamination of the starting PBMC concentrates with monocytes. Published by Elsevier Inc.

  3. Downregulation of proapoptotic Bim augments IL-2-independent T-cell transformation by human T-cell leukemia virus type-1 Tax

    PubMed Central

    Higuchi, Masaya; Takahashi, Masahiko; Tanaka, Yuetsu; Fujii, Masahiro

    2014-01-01

    Human T-cell leukemia virus type 1 (HTLV-1), an etiological agent of adult T-cell leukemia, immortalizes and transforms primary human T cells in vitro in both an interleukin (IL)-2-dependent and IL-2-independent manner. Expression of the HTLV-1 oncoprotein Tax transforms the growth of the mouse T-cell line CTLL-2 from being IL-2-dependent to IL-2-independent. Withdrawal of IL-2 from normal activated T cells induces apoptosis, which is mediated through the inducible expression of several proapoptotic proteins, including Bim. In this study, we found that Tax protects IL-2-depleted T cells against Bim-induced apoptosis. Withdrawal of IL-2 from CTLL-2 cells induced a prominent increase in the level of Bim protein in CTLL-2 cells, but not in Tax-transformed CTLL-2 cells. This inhibition of Bim in Tax-transformed CTLL-2 cells was mediated by two mechanisms: downregulation of Bim mRNA and posttranscriptional reduction of Bim protein. Transient expression of Tax in CTLL-2 cells also inhibited IL-2 depletion–induced expression of Bim, however, this decrease in Bim protein expression was not due to downregulation of Bim mRNA, thus indicating that Bim mRNA downregulation in Tax-transformed CTLL-2 occurs only after long-term expression of Tax. Transient expression of Tax in CTLL-2 cells also induced Erk activation, however, this was not involved in the reduction of Bim protein. Knockdown of Bim expression in CTLL-2 cells augmented Tax-induced IL-2-independent transformation. HTLV-1 infection of human T cells also reduced their levels of Bim protein, and restoring Bim expression in HTLV-1-infected cells reduced their proliferation by inducing apoptosis. Taken together, these results indicate that Tax-induced downregulation of Bim in HTLV-1-infected T cells promotes their IL-2-independent growth, thereby supporting the persistence of HTLV-1 infection in vivo. PMID:25175936

  4. Protection by universal influenza vaccine is mediated by memory CD4 T cells.

    PubMed

    Valkenburg, Sophie A; Li, Olive T W; Li, Athena; Bull, Maireid; Waldmann, Thomas A; Perera, Liyanage P; Peiris, Malik; Poon, Leo L M

    2018-07-05

    There is a diverse array of influenza viruses which circulate between different species, reassort and drift over time. Current seasonal influenza vaccines are ineffective in controlling these viruses. We have developed a novel universal vaccine which elicits robust T cell responses and protection against diverse influenza viruses in mouse and human models. Vaccine mediated protection was dependent on influenza-specific CD4 + T cells, whereby depletion of CD4 + T cells at either vaccination or challenge time points significantly reduced survival in mice. Vaccine memory CD4 + T cells were needed for early antibody production and CD8 + T cell recall responses. Furthermore, influenza-specific CD4 + T cells from vaccination manifested primarily Tfh and Th1 profiles with anti-viral cytokine production. The vaccine boosted H5-specific T cells from human PBMCs, specifically CD4 + and CD8 + T effector memory type, ensuring the vaccine was truly universal for its future application. These findings have implications for the development and optimization of T cell activating vaccines for universal immunity against influenza. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Human skin is protected by four functionally and phenotypically discrete populations of resident and recirculating memory T cells

    PubMed Central

    Watanabe, Rei; Gehad, Ahmed; Yang, Chao; Campbell, Laura; Teague, Jessica E.; Schlapbach, Christoph; Elco, Christopher; Huang, Victor; Matos, Tiago R.; Kupper, Thomas S.; Clark, Rachael A.

    2015-01-01

    The skin of an adult human contains approximately 20 billion memory T cells. Epithelial barrier tissues are infiltrated by a combination of resident and recirculating T cells in mice but the relative proportions and functional activities of resident versus recirculating T cells have not been evaluated in human skin. We discriminated resident from recirculating T cells in human engrafted mice and lymphoma patients using alemtuzumab, a medication that depletes recirculating T cells from skin, and then analyzed these T cell populations in healthy human skin. All non-recirculating resident memory T cells (TRM) expressed CD69, but the majority were CD4+, CD103− and located in the dermis, in contrast to studies in mice. Both CD4+ and CD8+ CD103+ TRM were enriched in the epidermis, had potent effector functions and had a limited proliferative capacity compared to CD103− TRM. TRM of both types had more potent effector functions than recirculating T cells. Induction of CD103 on human T cells was enhanced by keratinocyte contact, depended on TGFβ and was independent of T cell keratinocyte adhesive interactions. We observed two distinct populations of recirculating T cells, CCR7+/L-selectin+ central memory T cells (TCM) and CCR7+/L-selectin− T cells, which we term migratory memory T cells (TMM). Circulating skin-tropic TMM were intermediate in cytokine production between TCM and effector memory T cells. In patients with cutaneous T cell lymphoma, malignant TCM and TMM induced distinct inflammatory skin lesions and TMM were depleted more slowly from skin after alemtuzumab, suggesting TMM may recirculate more slowly. In summary, human skin is protected by four functionally distinct populations of T cells, two resident and two recirculating, with differing territories of migration and distinct functional activities. PMID:25787765

  6. Multicenter survey on the outcome of transplantation of hematopoietic cells in patients with the complete form of DiGeorge anomaly

    PubMed Central

    Sedlacek, Petr; Hönig, Manfred; Friedrich, Wilhelm; Champagne, Martin; Matsumoto, Tadashi; Fischer, Alain; Neven, Benedicte; Contet, Audrey; Bensoussan, Danielle; Bordigoni, Pierre; Loeb, David; Savage, William; Jabado, Nada; Bonilla, Francisco A.; Slatter, Mary A.; Davies, E. Graham; Gennery, Andrew R.

    2010-01-01

    Seventeen patients transplanted with hematopoietic cells to correct severe T lymphocyte immunodeficiency resulting from complete DiGeorge anomaly were identified worldwide, and retrospective data were obtained using a questionnaire-based survey. Patients were treated at a median age of 5 months (range, 2-53 months) between 1995 and 2006. Bone marrow was used in 11 procedures in 9 cases: 6 from matched unrelated donors, 4 from human leukocyte antigen (HLA)-identical siblings, and one haploidentical parent with T-cell depletion. Unmobilized peripheral blood was used in 8 cases: 5 from HLA-identical siblings, one from a matched unrelated donor, one from an HLA-identical parent, and one unrelated matched cord blood. Conditioning was used in 5 patients and graft-versus-host disease prophylaxis in 11 patients. Significant graft-versus-host disease occurred in 9 patients, becoming chronic in 3. Median length of follow-up was 13 months, with transplantation from HLA-matched sibling showing the best results. Median survival among deceased patients (10 patients) was 7 months after transplantation (range, 2-18 months). The overall survival rate was 41%, with a median follow-up of 5.8 years (range, 4-11.5 years). Among survivors, median CD3 and CD4 counts were 806 (range, 644-1224) and 348 (range, 225-782) cells/mm3, respectively, CD4+/CD45RA+ cells remained very low, whereas mitogen responses were normalized. PMID:20530285

  7. α4+β7hiCD4+ Memory T cells Harbor Most Th-17 cells and are Preferentially Infected During Acute SIV Infection

    PubMed Central

    Kader, Muhamuda; Wang, Xiaolei; Piatak, Michael; Lifson, Jeffrey; Roederer, Mario; Veazey, Ronald; Mattapallil, Joseph J.

    2009-01-01

    HIV/SIV are thought to infect minimally activated CD4+ T cells after viral entry. Not much is known about why SIV selectively targets these cells. Here we show that CD4+ T cells that express high levels of the α4β7 heterodimer are preferentially infected very early during the course of SIV infection. At day 2–4 post infection, α4+β7hiCD4+ T cells had ∼ 5x more SIV-gag DNA than β7−CD4+ T cells. α4+β7hiCD4+ T cells displayed a predominantly central memory (CD45RA−CD28+CCR7+) and resting (CD25−CD69−HLA-DR−Ki-67−) phenotype. Though the expression of detectable CCR5 was variable on α4+β7hi and β7−CD4+ T cells, both CCR5+ and CCR5− subsets of α4+β7hi and β7−CD4+ T cells were found to express sufficient levels of CCR5 mRNA suggesting that both these subsets could be efficiently infected by SIV. In line with this, we found similar levels of SIV infection in β7−CD4+CCR5+ and β7−CD4+CCR5− T cells. α4β7hiCD4+ T cells were found to harbor most Th-17 cells that were significantly depleted during acute SIV infection. Taken together, our results show that resting memory α4+β7hiCD4+ T cells in blood are preferentially depleted during acute SIV infection, and the loss of these cells alters the balance between Th-17 and Th-1 responses thereby contributing to disease pathogenesis. PMID:19571800

  8. Transfer of allogeneic CD4+ T cells rescues CD8+ T cells in anti-PD-L1–resistant tumors leading to tumor eradication

    PubMed Central

    Arina, Ainhoa; Karrison, Theodore; Galka, Eva; Schreiber, Karin; Weichselbaum, Ralph R.; Schreiber, Hans

    2017-01-01

    Adoptively transferred CD8+ T cells can stabilize the size of solid tumors over long periods of time by exclusively recognizing antigen cross-presented on tumor stroma. However, these tumors eventually escape T cell–mediated growth control. The aim of this study was to eradicate such persistent cancers. In our model, the SIYRYYGL antigen is expressed by cancer cells that lack the MHC-I molecule Kb needed for direct presentation, but the antigen is picked up and cross-presented by tumor stroma. A single injection of antigen-specific 2C CD8+ T cells caused long-term inhibition of tumor growth, but without further intervention, tumors started to progress after approximately 3 months. Escape was associated with reduced numbers of circulating 2C cells. Tumor-infiltrating 2C cells produced significantly less TNFα and expressed more of the “exhaustion” markers PD-1 and Tim-3 than T cells from lymphoid organs. High-dose local ionizing radiation, depletion of myeloid-derived suppressor cells, infusions of additional 2C cells, and antibodies blocking PD-L1 did not prevent tumor escape. In contrast, adoptive transfer of allogeneic CD4+ T cells restored the numbers of circulating Ag-specific CD8+ T cells and their intratumoral function, resulting in tumor eradication. These CD4+ T cells had no antitumor effects in the absence of CD8+ T cells and recognized the alloantigen cross-presented on tumor stroma. CD4+ T cells might also be effective in cancer patients when PD1/PD-L1 blockade does not rescue intratumoral CD8+ T-cell function and tumors persist. PMID:28077434

  9. A Natural Variant of the T Cell Receptor-Signaling Molecule Vav1 Reduces Both Effector T Cell Functions and Susceptibility to Neuroinflammation.

    PubMed

    Kassem, Sahar; Gaud, Guillaume; Bernard, Isabelle; Benamar, Mehdi; Dejean, Anne S; Liblau, Roland; Fournié, Gilbert J; Colacios, Céline; Malissen, Bernard; Saoudi, Abdelhadi

    2016-07-01

    The guanine nucleotide exchange factor Vav1 is essential for transducing T cell antigen receptor signals and therefore plays an important role in T cell development and activation. Our previous genetic studies identified a locus on rat chromosome 9 that controls the susceptibility to neuroinflammation and contains a non-synonymous polymorphism in the major candidate gene Vav1. To formally demonstrate the causal implication of this polymorphism, we generated a knock-in mouse bearing this polymorphism (Vav1R63W). Using this model, we show that Vav1R63W mice display reduced susceptibility to experimental autoimmune encephalomyelitis (EAE) induced by MOG35-55 peptide immunization. This is associated with a lower production of effector cytokines (IFN-γ, IL-17 and GM-CSF) by autoreactive CD4 T cells. Despite increased proportion of Foxp3+ regulatory T cells in Vav1R63W mice, we show that this lowered cytokine production is intrinsic to effector CD4 T cells and that Treg depletion has no impact on EAE development. Finally, we provide a mechanism for the above phenotype by showing that the Vav1R63W variant has normal enzymatic activity but reduced adaptor functions. Together, these data highlight the importance of Vav1 adaptor functions in the production of inflammatory cytokines by effector T cells and in the susceptibility to neuroinflammation.

  10. A Natural Variant of the T Cell Receptor-Signaling Molecule Vav1 Reduces Both Effector T Cell Functions and Susceptibility to Neuroinflammation

    PubMed Central

    Kassem, Sahar; Bernard, Isabelle; Dejean, Anne S.; Liblau, Roland; Fournié, Gilbert J.; Colacios, Céline

    2016-01-01

    The guanine nucleotide exchange factor Vav1 is essential for transducing T cell antigen receptor signals and therefore plays an important role in T cell development and activation. Our previous genetic studies identified a locus on rat chromosome 9 that controls the susceptibility to neuroinflammation and contains a non-synonymous polymorphism in the major candidate gene Vav1. To formally demonstrate the causal implication of this polymorphism, we generated a knock-in mouse bearing this polymorphism (Vav1R63W). Using this model, we show that Vav1R63W mice display reduced susceptibility to experimental autoimmune encephalomyelitis (EAE) induced by MOG35-55 peptide immunization. This is associated with a lower production of effector cytokines (IFN-γ, IL-17 and GM-CSF) by autoreactive CD4 T cells. Despite increased proportion of Foxp3+ regulatory T cells in Vav1R63W mice, we show that this lowered cytokine production is intrinsic to effector CD4 T cells and that Treg depletion has no impact on EAE development. Finally, we provide a mechanism for the above phenotype by showing that the Vav1R63W variant has normal enzymatic activity but reduced adaptor functions. Together, these data highlight the importance of Vav1 adaptor functions in the production of inflammatory cytokines by effector T cells and in the susceptibility to neuroinflammation. PMID:27438086

  11. Weakly self-reactive T-cell clones can homeostatically expand when present at low numbers.

    PubMed

    Vrisekoop, Nienke; Artusa, Patricio; Monteiro, Joao P; Mandl, Judith N

    2017-01-01

    T-cell division is central to maintaining a stable T-cell pool in adults. It also enables T-cell expansion in neonates, and after depletion by chemotherapy, bone marrow transplantation, or infection. The same signals required for T-cell survival in lymphoreplete settings, IL-7 and T-cell receptor (TCR) interactions with self-peptide MHC (pMHC), induce division when T-cell numbers are low. The strength of reactivity for self-pMHC has been shown to correlate with the capacity of T cells to undergo lymphopenia-induced proliferation (LIP), in that weakly self-reactive T cells are unable to divide, implying that T-cell reconstitution would significantly skew the TCR repertoire toward TCRs with greater self-reactivity and thus compromise T-cell diversity. Here, we show that while CD4 + T cells with low self-pMHC reactivity experience more intense competition, they are able to divide when present at low enough cell numbers. Thus, at physiological precursor frequencies CD4 + T cells with low self-pMHC reactivity are able to contribute to the reconstitution of the T-cell pool. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Donor CD8+ T Cells Prevent Toxoplasma gondii De-Encystation but Fail To Rescue the Exhausted Endogenous CD8+ T Cell Population

    PubMed Central

    Bhadra, Rajarshi; Cobb, Dustin A.

    2013-01-01

    Functional exhaustion of CD8+ T cells due to increased expression of inhibitory molecule PD-1 (Programmed Death-1) causes reactivation of latent disease during later phases of chronic toxoplasmosis. Onset of disease recrudescence results in decreased parasite cyst burden concomitant with parasites undergoing stage conversion from a primarily encysted, quiescent bradyzoite to a fast-replicating, highly motile tachyzoite. Thus, reduced cyst burden is one of the early hallmarks of disease recrudescence. This was further validated by depleting gamma interferon (IFN-γ), a cytokine known to control latent toxoplasmosis, in chronically infected prerecrudescent mice. Since CD8+ T cells (an important source of IFN-γ) lose their functionality during the later phases of chronic toxoplasmosis, we next examined if adoptive transfer of functional CD8+ T cells from acutely infected donors to the chronically infected prerecrudescent hosts could impede parasite de-encystation and rescue exhausted CD8+ T cells. While the transfer of immune CD8+ T cells temporarily restricted the breakdown of cysts, the exhausted endogenous CD8+ T cell population was not rescued. Over time, the donor population got deleted, resulting in parasite de-encystation and host mortality. Considering that donor CD8+ T cells fail to become long-lived, one of the cardinal features of memory CD8+ T cells, it bears the implication that memory CD8 differentiation is impaired during chronic toxoplasmosis. Moreover, our data strongly suggest that while adoptive immunotherapy can prevent parasite de-encystation transiently, reduced antigen burden in the chronic phase by itself is insufficient for rescue of exhausted CD8+ T cells. The conclusions of this study have profound ramifications in designing immunotherapeutics against chronic toxoplasmosis. PMID:23817617

  13. Correlates of preserved CD4(+) T cell homeostasis during natural, nonpathogenic simian immunodeficiency virus infection of sooty mangabeys: implications for AIDS pathogenesis.

    PubMed

    Sumpter, Beth; Dunham, Richard; Gordon, Shari; Engram, Jessica; Hennessy, Margaret; Kinter, Audrey; Paiardini, Mirko; Cervasi, Barbara; Klatt, Nichole; McClure, Harold; Milush, Jeffrey M; Staprans, Silvija; Sodora, Donald L; Silvestri, Guido

    2007-02-01

    In contrast to HIV-infected humans, naturally SIV-infected sooty mangabeys (SMs) very rarely progress to AIDS. Although the mechanisms underlying this disease resistance are unknown, a consistent feature of natural SIV infection is the absence of the generalized immune activation associated with HIV infection. To define the correlates of preserved CD4(+) T cell counts in SMs, we conducted a cross-sectional immunological study of 110 naturally SIV-infected SMs. The nonpathogenic nature of the infection was confirmed by an average CD4(+) T cell count of 1,076 +/- 589/mm(3) despite chronic infection with a highly replicating virus. No correlation was found between CD4(+) T cell counts and either age (used as a surrogate marker for length of infection) or viremia. The strongest correlates of preserved CD4(+) T cell counts were a low percentage of circulating effector T cells (CD28(-)CD95(+) and/or IL-7R/CD127(-)) and a high percentage of CD4(+)CD25(+) T cells. These findings support the hypothesis that the level of immune activation is a key determinant of CD4(+) T cell counts in SIV-infected SMs. Interestingly, we identified 14 animals with CD4(+) T cell counts of <500/mm(3), of which two show severe and persistent CD4(+) T cell depletion (<50/mm(3)). Thus, significant CD4(+) T cell depletion does occasionally follow SIV infection of SMs even in the context of generally low levels of immune activation, lending support to the hypothesis of multifactorial control of CD4(+) T cell homeostasis in this model of infection. The absence of AIDS in these "CD4(low)" naturally SIV-infected SMs defines a protective role of the reduced immune activation even in the context of a significant CD4(+) T cell depletion.

  14. Therapeutic manipulation of natural killer (NK) T cells in autoimmunity: are we close to reality?

    PubMed Central

    Simoni, Y; Diana, J; Ghazarian, L; Beaudoin, L; Lehuen, A

    2013-01-01

    T cells reactive to lipids and restricted by major histocompatibility complex (MHC) class I-like molecules represent more than 15% of all lymphocytes in human blood. This heterogeneous population of innate cells includes the invariant natural killer T cells (iNK T), type II NK T cells, CD1a,b,c-restricted T cells and mucosal-associated invariant T (MAIT) cells. These populations are implicated in cancer, infection and autoimmunity. In this review, we focus on the role of these cells in autoimmunity. We summarize data obtained in humans and preclinical models of autoimmune diseases such as primary biliary cirrhosis, type 1 diabetes, multiple sclerosis, systemic lupus erythematosus, rheumatoid arthritis, psoriasis and atherosclerosis. We also discuss the promise of NK T cell manipulations: restoration of function, specific activation, depletion and the relevance of these treatments to human autoimmune diseases. PMID:23199318

  15. CD4 T cell-mediated masking effects of the immunogenicity of tumor-associated antigens are qualitatively and quantitatively different depending on the individual antigens.

    PubMed

    Okano, Shinji; Matsumoto, Yoshihiro; Yoshiya, Shohei; Yamashita, Yo-ichi; Harimoto, Norifumi; Ikegami, Toru; Shirabe, Ken; Harada, Mamoru; Yoshikai, Yasunobu; Maehara, Yoshihiko

    2013-01-01

    The use of cancer immunotherapy as part of multidisciplinary therapies for cancer is a promising strategy for the cure of advanced cancer patients. In cancer immunotherapy, the effective priming of tumor-associated antigen (TAA)-specific CD8+ T cells is essential, and therefore, the appropriate selection of the best peptide for targeting the cancer is a most important concern. One criticism in the selection of a TAA is the immunogenicity of the TAA, the vaccination of which effectively elicits clinical responses. However, the critical basic immunological factors that affect the differences in the immunogenicity of TAAs remain to be elucidated. Here we found that CD4 T-cell responses suppressed the immunogenicity of the concomitant TAA in a murine melanoma model in which intratumoral activated dendritic therapy (ITADT) was used for treatment of the established cancer, and we observed that the antitumor effects were largely dependent on the CD8 T-cell response. CD4 T-cell depletion simply enhanced the tyrosinase-related protein (TRP)-2(180-188) peptide-specific cytotoxic T-cell (CTL) responses, and CD4 T-cell depletion provided immunogenicity for mgp100(25-33) peptide, to which a CTL response could not be detected at all in CD4 T-cell-intact mice in the early therapeutic phase. Further, the mgp100(25-33) peptide-specific CTL response again became undetectable after the recovery of CD4 T cells in previously CD4-depleted, tumor-eradicated mice, whereas the TRP-2(180-188) peptide-specific CTL response was still much stronger in CD4-depleted mice than in CD4-intact mice. These findings suggest that the CD4 T cell-mediated masking effects of the immunogenicity of tumor-associated antigens are qualitatively and quantitatively different depending on the individual antigens.

  16. c-Myc-Induced Survivin Is Essential for Promoting the Notch-Dependent T Cell Differentiation from Hematopoietic Stem Cells

    PubMed Central

    Haque, Rizwanul; Song, Jianyong; Haque, Mohammad; Lei, Fengyang; Sandhu, Praneet; Ni, Bing; Zheng, Songguo; Fang, Deyu; Yang, Jin-Ming; Song, Jianxun

    2017-01-01

    Notch is indispensable for T cell lineage commitment, and is needed for thymocyte differentiation at early phases. During early stages of T cell development, active Notch prevents other lineage potentials including B cell lineage and myeloid cell (e.g., dendritic cell) lineage. Nevertheless, the precise intracellular signaling pathways by which Notch promotes T cell differentiation remain unclear. Here we report that the transcription factor c-Myc is a key mediator of the Notch signaling–regulated T cell differentiation. In a well-established in vitro differentiation model of T lymphocytes from hematopoietic stem cells, we showed that Notch1 and 4 directly promoted c-Myc expression; dominant-negative (DN) c-Myc inhibited early T cell differentiation. Moreover, the c-Myc expression activated by Notch signaling increased the expression of survivin, an inhibitor of apoptosis (IAP) protein. We further demonstrated that over-expression of c-Myc increased the abundance of survivin and the T cell differentiation thereof, whereas dn c-Myc reduced survivin levels and concomitantly retarded the differentiation. The c-Myc–dependent survivin induction is functionally germane, because Notch-dependent T cell differentiation was canceled by the depletion of survivin. These results identify both c-Myc and survivin as important mediators of the Notch signaling–regulated differentiation of T lymphocytes from hematopoietic stem cells. PMID:28272325

  17. B-cell-depleting Therapy in Systemic Lupus Erythematosus

    PubMed Central

    Ramos-Casals, Manuel; Sanz, Iñaki; Bosch, Xavier; Stone, John H.; Khamashta, Munther A.

    2014-01-01

    The emergence of a new class of agents (B-cell-depleting therapies) has opened a new era in the therapeutic approach to systemic lupus erythematosus, with belimumab being the first drug licensed for use in systemic lupus erythematosus in more than 50 years. Four agents deserve specific mention: rituximab, ocrelizumab, epratuzumab, and belimumab. Controlled trials have shown negative results for rituximab, promising results for epratuzumab, and positive results for belimumab. Despite these negative results, rituximab is the most-used agent in patients who do not respond or are intolerant to standard therapy and those with life-threatening presentations. B-cell-depleting agents should not be used in patients with mild disease and should be tailored according to individual patient characteristics, including ethnicity, organ involvement, and the immunological profile. Forthcoming studies of B-cell-directed strategies, particularly data from investigations of off-label rituximab use and postmarketing studies of belimumab, will provide new insights into the utility of these treatments in the routine management of patients with systemic lupus erythematosus. PMID:22444096

  18. TIF-IA and Ebp1 regulate RNA synthesis in T cells.

    PubMed

    Saudemont, Aurore

    2015-04-16

    In this issue of Blood, Nguyen et al show that mycophenolic acid (MPA) induces GTP depletion, which inhibits the function of transcription initiation factor I (TIF-IA) and impacts the interaction of TIF-IA with ErbB3-binding protein 1 (Ebp1), a key in regulating proliferating cell nuclear antigen (PCNA) expression and ribosomal RNA (rRNA) synthesis in T cells during activation.

  19. Checkpoint Antibodies but not T Cell-Recruiting Diabodies Effectively Synergize with TIL-Inducing γ-Irradiation.

    PubMed

    Hettich, Michael; Lahoti, Jayashree; Prasad, Shruthi; Niedermann, Gabriele

    2016-08-15

    T cell-recruiting bispecific antibodies (bsAb) show promise in hematologic malignancies and are also being evaluated in solid tumors. In this study, we investigated whether T cell-recruiting bsAbs synergize with hypofractionated tumor radiotherapy (hRT) and/or blockade of the programmed death-1 (PD-1) immune checkpoint, both of which can increase tumor-infiltrating lymphocyte (TIL) numbers. Unexpectedly, large melanomas treated with hRT plus bsAb (AC133×CD3) relapsed faster than those treated with hRT alone, accompanied by massive TIL apoptosis. This fast relapse was delayed by the further addition of anti-PD-1. Mechanistic investigations revealed restimulation-induced cell death mediated by BIM and FAS as an additional cause of bsAb-mediated TIL depletion. In contrast, the double combination of hRT and anti-PD-1 strongly increased TIL numbers, and even very large tumors were completely eradicated. Our study reveals the risk that CD3-engaging bsAbs can induce apoptotic TIL depletion followed by rapid tumor regrowth, reminiscent of tolerance induction by CD3 mAb-mediated T-cell depletion, warranting caution in their use for the treatment of solid tumors. Our findings also argue that combining radiotherapy and anti-PD-1 can be quite potent, including against very large tumors. Cancer Res; 76(16); 4673-83. ©2016 AACR. ©2016 American Association for Cancer Research.

  20. Reduced-Intensity Transplantation for Lymphomas Using Haploidentical Related Donors Versus HLA-Matched Sibling Donors: A Center for International Blood and Marrow Transplant Research Analysis.

    PubMed

    Ghosh, Nilanjan; Karmali, Reem; Rocha, Vanderson; Ahn, Kwang Woo; DiGilio, Alyssa; Hari, Parameswaran N; Bachanova, Veronika; Bacher, Ulrike; Dahi, Parastoo; de Lima, Marcos; D'Souza, Anita; Fenske, Timothy S; Ganguly, Siddhartha; Kharfan-Dabaja, Mohamed A; Prestidge, Tim D; Savani, Bipin N; Smith, Sonali M; Sureda, Anna M; Waller, Edmund K; Jaglowski, Samantha; Herrera, Alex F; Armand, Philippe; Salit, Rachel B; Wagner-Johnston, Nina D; Fuchs, Ephraim; Bolaños-Meade, Javier; Hamadani, Mehdi

    2016-09-10

    Related donor haploidentical hematopoietic cell transplantation (Haplo-HCT) using post-transplantation cyclophosphamide (PT-Cy) is increasingly used in patients lacking HLA-matched sibling donors (MSD). We compared outcomes after Haplo-HCT using PT-Cy with MSD-HCT in patients with lymphoma, using the Center for International Blood and Marrow Transplant Research registry. We evaluated 987 adult patients undergoing either Haplo-HCT (n = 180) or MSD-HCT (n = 807) following reduced-intensity conditioning regimens. The haploidentical group received graft-versus-host disease (GVHD) prophylaxis with PT-Cy with or without a calcineurin inhibitor and mycophenolate. The MSD group received calcineurin inhibitor-based GVHD prophylaxis. Median follow-up of survivors was 3 years. The 28-day neutrophil recovery was similar in the two groups (95% v 97%; P = .31). The 28-day platelet recovery was delayed in the haploidentical group compared with the MSD group (63% v 91%; P = .001). Cumulative incidence of grade II to IV acute GVHD at day 100 was similar between the two groups (27% v 25%; P = .84). Cumulative incidence of chronic GVHD at 1 year was significantly lower after Haplo-HCT (12% v 45%; P < .001), and this benefit was confirmed on multivariate analysis (relative risk, 0.21; 95% CI, 0.14 to 0.31; P < .001). For Haplo-HCT v MSD-HCT, 3-year rates of nonrelapse mortality (15% v 13%; P = .41), relapse/progression (37% v 40%; P = .51), progression-free survival (48% v 48%; P = .96), and overall survival (61% v 62%; P = .82) were similar. Multivariate analysis showed no significant difference between Haplo-HCT and MSD-HCT in terms of nonrelapse mortality (P = .06), progression/relapse (P = .10), progression-free survival (P = .83), and overall survival (P = .34). Haplo-HCT with PT-Cy provides survival outcomes comparable to MSD-HCT, with a significantly lower risk of chronic GVHD. © 2016 by American Society of Clinical Oncology.

  1. Reduced-Intensity Transplantation for Lymphomas Using Haploidentical Related Donors Versus HLA-Matched Sibling Donors: A Center for International Blood and Marrow Transplant Research Analysis

    PubMed Central

    Ghosh, Nilanjan; Karmali, Reem; Rocha, Vanderson; Ahn, Kwang Woo; DiGilio, Alyssa; Hari, Parameswaran N.; Bachanova, Veronika; Bacher, Ulrike; Dahi, Parastoo; de Lima, Marcos; D’Souza, Anita; Fenske, Timothy S.; Ganguly, Siddhartha; Kharfan-Dabaja, Mohamed A.; Prestidge, Tim D.; Savani, Bipin N.; Smith, Sonali M.; Sureda, Anna M.; Waller, Edmund K.; Jaglowski, Samantha; Herrera, Alex F.; Armand, Philippe; Salit, Rachel B.; Wagner-Johnston, Nina D.; Fuchs, Ephraim; Bolaños-Meade, Javier

    2016-01-01

    Purpose Related donor haploidentical hematopoietic cell transplantation (Haplo-HCT) using post-transplantation cyclophosphamide (PT-Cy) is increasingly used in patients lacking HLA-matched sibling donors (MSD). We compared outcomes after Haplo-HCT using PT-Cy with MSD-HCT in patients with lymphoma, using the Center for International Blood and Marrow Transplant Research registry. Materials and Methods We evaluated 987 adult patients undergoing either Haplo-HCT (n = 180) or MSD-HCT (n = 807) following reduced-intensity conditioning regimens. The haploidentical group received graft-versus-host disease (GVHD) prophylaxis with PT-Cy with or without a calcineurin inhibitor and mycophenolate. The MSD group received calcineurin inhibitor–based GVHD prophylaxis. Results Median follow-up of survivors was 3 years. The 28-day neutrophil recovery was similar in the two groups (95% v 97%; P = .31). The 28-day platelet recovery was delayed in the haploidentical group compared with the MSD group (63% v 91%; P = .001). Cumulative incidence of grade II to IV acute GVHD at day 100 was similar between the two groups (27% v 25%; P = .84). Cumulative incidence of chronic GVHD at 1 year was significantly lower after Haplo-HCT (12% v 45%; P < .001), and this benefit was confirmed on multivariate analysis (relative risk, 0.21; 95% CI, 0.14 to 0.31; P < .001). For Haplo-HCT v MSD-HCT, 3-year rates of nonrelapse mortality (15% v 13%; P = .41), relapse/progression (37% v 40%; P = .51), progression-free survival (48% v 48%; P = .96), and overall survival (61% v 62%; P = .82) were similar. Multivariate analysis showed no significant difference between Haplo-HCT and MSD-HCT in terms of nonrelapse mortality (P = .06), progression/relapse (P = .10), progression-free survival (P = .83), and overall survival (P = .34). Conclusion Haplo-HCT with PT-Cy provides survival outcomes comparable to MSD-HCT, with a significantly lower risk of chronic GVHD. PMID:27269951

  2. Human NK cells: From surface receptors to clinical applications.

    PubMed

    Moretta, Lorenzo; Pietra, Gabriella; Vacca, Paola; Pende, Daniela; Moretta, Francesca; Bertaina, Alice; Mingari, Maria Cristina; Locatelli, Franco; Moretta, Alessandro

    2016-10-01

    Natural killer (NK) cells play a major role in innate defenses against pathogens, primarily viruses, and are also thought to be part of the immunosurveillance against tumors. They express an array of surface receptors that mediate NK cell function. The human leukocytes antigen (HLA) class I-specific inhibitory receptors allow NK cells to detect and kill cells that have lost or under-express HLA class I antigens, a typical feature of tumor or virally infected cells. However, NK cell activation and induction of cytolytic activity and cytokine production depends on another important checkpoint, namely the expression on target cells of ligands recognized by activating NK receptors. Despite their potent cytolytic activity, NK cells frequently fail to eliminate tumors. This is due to mechanisms of tumor escape, determined by the tumor cells themselves or by tumor-associated cells (i.e. the tumor microenvironment) via the release of soluble suppressive factors or the induction of inhibitory loops involving induction of regulatory T cells, M2-polarized macrophages and myeloid-derived suppressor cells. The most important clinical application involving NK cells is the cure of high-risk leukemias in the haplo-identical hematopoietic stem cell transplant (HSCT) setting. NK cells originated from hematopoietic stem cells (HSC) of HLA-haploidentical donors may express Killer Immunoglobulin-like receptors (KIRs) that are mismatched with the HLA class I alleles of the recipient. This allows NK cells to kill leukemia blasts residual after the conditioning regimen, while sparing normal cells (that do not express ligands for activating NK receptors). More recent approaches based on the specific removal of TCR α/β(+) T cells and of CD19(+) B cells, allow the infusion, together with CD34(+) HSC, of mature KIR(+) NK cells and of TCR γ/δ(+) T cells, both characterized by a potent anti-leukemia activity. This greatly reduces the time interval necessary to obtain alloreactive, KIR(+) NK

  3. Improving B-cell depletion in systemic lupus erythematosus and rheumatoid arthritis.

    PubMed

    Mota, Pedro; Reddy, Venkat; Isenberg, David

    2017-07-01

    Rituximab-based B-cell depletion (BCD) therapy is effective in refractory rheumatoid arthritis (RA) and although used to treat patients with refractory systemic lupus erythematosus (SLE) in routine clinical practice, rituximab failed to meet the primary endpoints in two large randomised controlled trials (RCTs) of non-renal (EXPLORER) and renal (LUNAR) SLE. Areas covered: We review how BCD could be improved to achieve better clinical responses in RA and SLE. Insights into the variability in clinical response to BCD in RA and SLE may help develop new therapeutic strategies. To this end, a literature search was performed using the following terms: rheumatoid arthritis, systemic erythematosus lupus, rituximab and B-cell depletion. Expert commentary: Poor trial design may have, at least partly, contributed to the apparent lack of response to BCD in the two RCTs of patients with SLE. Enhanced B-cell depletion and/or sequential therapy with belimumab may improve clinical response at least in some patients with SLE.

  4. Hili Inhibits HIV Replication in Activated T Cells.

    PubMed

    Peterlin, B Matija; Liu, Pingyang; Wang, Xiaoyun; Cary, Daniele; Shao, Wei; Leoz, Marie; Hong, Tian; Pan, Tao; Fujinaga, Koh

    2017-06-01

    P-element-induced wimpy-like (Piwil) proteins restrict the replication of mobile genetic elements in the germ line. They are also expressed in many transformed cell lines. In this study, we discovered that the human Piwil 2 (Hili) protein can also inhibit HIV replication, especially in activated CD4 + T cells that are the preferred target cells for this virus in the infected host. Although resting cells did not express Hili, its expression was rapidly induced following T cell activation. In these cells and transformed cell lines, depletion of Hili increased levels of viral proteins and new viral particles. Further studies revealed that Hili binds to tRNA. Some of the tRNAs represent rare tRNA species, whose codons are overrepresented in the viral genome. Targeting tRNA Arg (UCU) with an antisense oligonucleotide replicated effects of Hili and also inhibited HIV replication. Finally, Hili also inhibited the retrotransposition of the endogenous intracysternal A particle (IAP) by a similar mechanism. Thus, Hili joins a list of host proteins that inhibit the replication of HIV and other mobile genetic elements. IMPORTANCE Piwil proteins inhibit the movement of mobile genetic elements in the germ line. In their absence, sperm does not form and male mice are sterile. This inhibition is thought to occur via small Piwi-interacting RNAs (piRNAs). However, in some species and in human somatic cells, Piwil proteins bind primarily to tRNA. In this report, we demonstrate that human Piwil proteins, especially Hili, not only bind to select tRNA species, including rare tRNAs, but also inhibit HIV replication. Importantly, T cell activation induces the expression of Hili in CD4 + T cells. Since Hili also inhibited the movement of an endogenous retrovirus (IAP), our finding shed new light on this intracellular resistance to exogenous and endogenous retroviruses as well as other mobile genetic elements. Copyright © 2017 American Society for Microbiology.

  5. Deferasirox-induced iron depletion promotes BclxL downregulation and death of proximal tubular cells

    PubMed Central

    Martin-Sanchez, Diego; Gallegos-Villalobos, Angel; Fontecha-Barriuso, Miguel; Carrasco, Susana; Sanchez-Niño, Maria Dolores; Lopez-Hernandez, Francisco J; Ruiz-Ortega, Marta; Egido, Jesus; Ortiz, Alberto; Sanz, Ana Belén

    2017-01-01

    Iron deficiency has been associated with kidney injury. Deferasirox is an oral iron chelator used to treat blood transfusion-related iron overload. Nephrotoxicity is the most serious and common adverse effect of deferasirox and may present as an acute or chronic kidney disease. However, scarce data are available on the molecular mechanisms of nephrotoxicity. We explored the therapeutic modulation of deferasirox-induced proximal tubular cell death in culture. Deferasirox induced dose-dependent tubular cell death and AnexxinV/7AAD staining showed features of apoptosis and necrosis. However, despite inhibiting caspase-3 activation, the pan-caspase inhibitor zVAD-fmk failed to prevent deferasirox-induced cell death. Moreover, zVAD increased deferasirox-induced cell death, a feature sometimes found in necroptosis. Electron microscopy identified mitochondrial injury and features of necrosis. However, neither necrostatin-1 nor RIP3 knockdown prevented deferasirox-induced cell death. Deferasirox caused BclxL depletion and BclxL overexpression was protective. Preventing iron depletion protected from BclxL downregulation and deferasirox cytotoxicity. In conclusion, deferasirox promoted iron depletion-dependent cell death characterized by BclxL downregulation. BclxL overexpression was protective, suggesting a role for BclxL downregulation in iron depletion-induced cell death. This information may be used to develop novel nephroprotective strategies. Furthermore, it supports the concept that monitoring kidney tissue iron depletion may decrease the risk of deferasirox nephrotoxicity. PMID:28139717

  6. Deferasirox-induced iron depletion promotes BclxL downregulation and death of proximal tubular cells.

    PubMed

    Martin-Sanchez, Diego; Gallegos-Villalobos, Angel; Fontecha-Barriuso, Miguel; Carrasco, Susana; Sanchez-Niño, Maria Dolores; Lopez-Hernandez, Francisco J; Ruiz-Ortega, Marta; Egido, Jesus; Ortiz, Alberto; Sanz, Ana Belén

    2017-01-31

    Iron deficiency has been associated with kidney injury. Deferasirox is an oral iron chelator used to treat blood transfusion-related iron overload. Nephrotoxicity is the most serious and common adverse effect of deferasirox and may present as an acute or chronic kidney disease. However, scarce data are available on the molecular mechanisms of nephrotoxicity. We explored the therapeutic modulation of deferasirox-induced proximal tubular cell death in culture. Deferasirox induced dose-dependent tubular cell death and AnexxinV/7AAD staining showed features of apoptosis and necrosis. However, despite inhibiting caspase-3 activation, the pan-caspase inhibitor zVAD-fmk failed to prevent deferasirox-induced cell death. Moreover, zVAD increased deferasirox-induced cell death, a feature sometimes found in necroptosis. Electron microscopy identified mitochondrial injury and features of necrosis. However, neither necrostatin-1 nor RIP3 knockdown prevented deferasirox-induced cell death. Deferasirox caused BclxL depletion and BclxL overexpression was protective. Preventing iron depletion protected from BclxL downregulation and deferasirox cytotoxicity. In conclusion, deferasirox promoted iron depletion-dependent cell death characterized by BclxL downregulation. BclxL overexpression was protective, suggesting a role for BclxL downregulation in iron depletion-induced cell death. This information may be used to develop novel nephroprotective strategies. Furthermore, it supports the concept that monitoring kidney tissue iron depletion may decrease the risk of deferasirox nephrotoxicity.

  7. Targeting Tumor Oct4 to Deplete Prostate Tumor and Metastasis Initiating Cells

    DTIC Science & Technology

    2016-10-01

    Award Number: W81XWH-13-1-0461 TITLE: Targeting Tumor Oct4 to Deplete Prostate Tumor- and Metastasis-Initiating Cells PRINCIPAL INVESTIGATOR: Daotai...29 2016 4. TITLE AND SUBTILE Targeting Tumor Oct4 to Deplete Prostate Tumor- and Metastasis-Initiating Cells 5a. CONTRACT NUMBER 5b. GRANT NUMBER...the c-MYC oncogene. POU5F1B is a pseudogene of embryonic Oct4 (POU5F1). A recent study found that tumor Oct4 found in prostate cancer cells is due

  8. T Cells and Pathogenesis of Hantavirus Cardiopulmonary Syndrome and Hemorrhagic Fever with Renal Syndrome

    PubMed Central

    Terajima, Masanori; Ennis, Francis A.

    2011-01-01

    We previously hypothesized that increased capillary permeability observed in both hantavirus cardiopulmonary syndrome (HCPS) and hemorrhagic fever with renal syndrome (HFRS) may be caused by hantavirus-specific cytotoxic T cells attacking endothelial cells presenting viral antigens on their surface based on clinical observations and in vitro experiments. In HCPS, hantavirus-specific T cell responses positively correlated with disease severity. In HFRS, in one report, contrary to HCPS, T cell responses negatively correlated with disease severity, but in another report the number of regulatory T cells, which are thought to suppress T cell responses, negatively correlated with disease severity. In rat experiments, in which hantavirus causes persistent infection, depletion of regulatory T cells helped infected rats clear virus without inducing immunopathology. These seemingly contradictory findings may suggest delicate balance in T cell responses between protection and immunopathogenesis. Both too strong and too weak T cell responses may lead to severe disease. It is important to clarify the role of T cells in these diseases for better treatment (whether to suppress T cell functions) and protection (vaccine design) which may need to take into account viral factors and the influence of HLA on T cell responses. PMID:21994770

  9. T cells and pathogenesis of hantavirus cardiopulmonary syndrome and hemorrhagic fever with renal syndrome.

    PubMed

    Terajima, Masanori; Ennis, Francis A

    2011-07-01

    We previously hypothesized that increased capillary permeability observed in both hantavirus cardiopulmonary syndrome (HCPS) and hemorrhagic fever with renal syndrome (HFRS) may be caused by hantavirus-specific cytotoxic T cells attacking endothelial cells presenting viral antigens on their surface based on clinical observations and in vitro experiments. In HCPS, hantavirus-specific T cell responses positively correlated with disease severity. In HFRS, in one report, contrary to HCPS, T cell responses negatively correlated with disease severity, but in another report the number of regulatory T cells, which are thought to suppress T cell responses, negatively correlated with disease severity. In rat experiments, in which hantavirus causes persistent infection, depletion of regulatory T cells helped infected rats clear virus without inducing immunopathology. These seemingly contradictory findings may suggest delicate balance in T cell responses between protection and immunopathogenesis. Both too strong and too weak T cell responses may lead to severe disease. It is important to clarify the role of T cells in these diseases for better treatment (whether to suppress T cell functions) and protection (vaccine design) which may need to take into account viral factors and the influence of HLA on T cell responses.

  10. B cell depletion therapy ameliorates autoimmune disease through ablation of IL-6–producing B cells

    PubMed Central

    Shen, Ping; Brown, Sheila; Lampropoulou, Vicky; Roch, Toralf; Lawrie, Sarah; Fan, Boli; O’Connor, Richard A.; Anderton, Stephen M.; Bar-Or, Amit; Fillatreau, Simon; Gray, David

    2012-01-01

    B cells have paradoxical roles in autoimmunity, exerting both pathogenic and protective effects. Pathogenesis may be antibody independent, as B cell depletion therapy (BCDT) leads to amelioration of disease irrespective of autoantibody ablation. However, the mechanisms of pathogenesis are poorly understood. We demonstrate that BCDT alleviates central nervous system autoimmunity through ablation of IL-6–secreting pathogenic B cells. B cells from mice with experimental autoimmune encephalomyelitis (EAE) secreted elevated levels of IL-6 compared with B cells from naive controls, and mice with a B cell–specific IL-6 deficiency showed less severe disease than mice with wild-type B cells. Moreover, BCDT ameliorated EAE only in mice with IL-6–sufficient B cells. This mechanism of pathogenesis may also operate in multiple sclerosis (MS) because B cells from MS patients produced more IL-6 than B cells from healthy controls, and this abnormality was normalized with B cell reconstitution after Rituximab treatment. This suggests that BCDT improved disease progression, at least partly, by eliminating IL-6–producing B cells in MS patients. Taking these data together, we conclude that IL-6 secretion is a major mechanism of B cell–driven pathogenesis in T cell–mediated autoimmune disease such as EAE and MS. PMID:22547654

  11. Progressive CD4+ central–memory T cell decline results in CD4+ effector–memory insufficiency and overt disease in chronic SIV infection

    PubMed Central

    Okoye, Afam; Meier-Schellersheim, Martin; Brenchley, Jason M.; Hagen, Shoko I.; Walker, Joshua M.; Rohankhedkar, Mukta; Lum, Richard; Edgar, John B.; Planer, Shannon L.; Legasse, Alfred; Sylwester, Andrew W.; Piatak, Michael; Lifson, Jeffrey D.; Maino, Vernon C.; Sodora, Donald L.; Douek, Daniel C.; Axthelm, Michael K.; Grossman, Zvi; Picker, Louis J.

    2007-01-01

    Primary simian immunodeficiency virus (SIV) infections of rhesus macaques result in the dramatic depletion of CD4+ CCR5+ effector–memory T (TEM) cells from extra-lymphoid effector sites, but in most infections, an increased rate of CD4+ memory T cell proliferation appears to prevent collapse of effector site CD4+ TEM cell populations and acute-phase AIDS. Eventually, persistent SIV replication results in chronic-phase AIDS, but the responsible mechanisms remain controversial. Here, we demonstrate that in the chronic phase of progressive SIV infection, effector site CD4+ TEM cell populations manifest a slow, continuous decline, and that the degree of this depletion remains a highly significant correlate of late-onset AIDS. We further show that due to persistent immune activation, effector site CD4+ TEM cells are predominantly short-lived, and that their homeostasis is strikingly dependent on the production of new CD4+ TEM cells from central–memory T (TCM) cell precursors. The instability of effector site CD4+ TEM cell populations over time was not explained by increasing destruction of these cells, but rather was attributable to progressive reduction in their production, secondary to decreasing numbers of CCR5− CD4+ TCM cells. These data suggest that although CD4+ TEM cell depletion is a proximate mechanism of immunodeficiency, the tempo of this depletion and the timing of disease onset are largely determined by destruction, failing production, and gradual decline of CD4+ TCM cells. PMID:17724130

  12. Suppression of IL-7-dependent Effector T-cell Expansion by Multipotent Adult Progenitor Cells and PGE2

    PubMed Central

    Reading, James L; Vaes, Bart; Hull, Caroline; Sabbah, Shereen; Hayday, Thomas; Wang, Nancy S; DiPiero, Anthony; Lehman, Nicholas A; Taggart, Jen M; Carty, Fiona; English, Karen; Pinxteren, Jef; Deans, Robert; Ting, Anthony E; Tree, Timothy I M

    2015-01-01

    T-cell depletion therapy is used to prevent acute allograft rejection, treat autoimmunity and create space for bone marrow or hematopoietic cell transplantation. The evolved response to T-cell loss is a transient increase in IL-7 that drives compensatory homeostatic proliferation (HP) of mature T cells. Paradoxically, the exaggerated form of this process that occurs following lymphodepletion expands effector T-cells, often causing loss of immunological tolerance that results in rapid graft rejection, autoimmunity, and exacerbated graft-versus-host disease (GVHD). While standard immune suppression is unable to treat these pathologies, growing evidence suggests that manipulating the incipient process of HP increases allograft survival, prevents autoimmunity, and markedly reduces GVHD. Multipotent adult progenitor cells (MAPC) are a clinical grade immunomodulatory cell therapy known to alter γ-chain cytokine responses in T-cells. Herein, we demonstrate that MAPC regulate HP of human T-cells, prevent the expansion of Th1, Th17, and Th22 effectors, and block the development of pathogenic allograft responses. This occurs via IL-1β-primed secretion of PGE2 and activates T-cell intrinsic regulatory mechanisms (SOCS2, GADD45A). These data provide proof-of-principle that HP of human T-cells can be targeted by cellular and molecular therapies and lays a basis for the development of novel strategies to prevent immunopathology in lymphodepleted patients. PMID:26216515

  13. Metabolite Depletion Affects Flux Profiling of Cell Lines.

    PubMed

    Nilsson, A; Haanstra, J R; Teusink, B; Nielsen, J

    2018-06-01

    Quantifying the rate of consumption and release of metabolites (i.e., flux profiling) has become integral to the study of cancer. The fluxes as well as the growth of the cells may be affected by metabolite depletion during cultivation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. CD4+ virtual memory: Antigen-inexperienced T cells reside in the naïve, regulatory, and memory T cell compartments at similar frequencies, implications for autoimmunity.

    PubMed

    Marusina, Alina I; Ono, Yoko; Merleev, Alexander A; Shimoda, Michiko; Ogawa, Hiromi; Wang, Elizabeth A; Kondo, Kayo; Olney, Laura; Luxardi, Guillaume; Miyamura, Yoshinori; Yilma, Tilahun D; Villalobos, Itzel Bustos; Bergstrom, Jennifer W; Kronenberg, Daniel G; Soulika, Athena M; Adamopoulos, Iannis E; Maverakis, Emanual

    2017-02-01

    It is widely accepted that central and effector memory CD4 + T cells originate from naïve T cells after they have encountered their cognate antigen in the setting of appropriate co-stimulation. However, if this were true the diversity of T cell receptor (TCR) sequences within the naïve T cell compartment should be far greater than that of the memory T cell compartment, which is not supported by TCR sequencing data. Here we demonstrate that aged mice with far fewer naïve T cells, respond to the model antigen, hen eggwhite lysozyme (HEL), by utilizing the same TCR sequence as their younger counterparts. CD4 + T cell repertoire analysis of highly purified T cell populations from naive animals revealed that the HEL-specific clones displayed effector and central "memory" cell surface phenotypes even prior to having encountered their cognate antigen. Furthermore, HEL-inexperienced CD4 + T cells were found to reside within the naïve, regulatory, central memory, and effector memory T cell populations at similar frequencies and the majority of the CD4 + T cells within the regulatory and memory populations were unexpanded. These findings support a new paradigm for CD4 + T cell maturation in which a specific clone can undergo a differentiation process to exhibit a "memory" or regulatory phenotype without having undergone a clonal expansion event. It also demonstrates that a foreign-specific T cell is just as likely to reside within the regulatory T cell compartment as it would the naïve compartment, arguing against the specificity of the regulatory T cell compartment being skewed towards self-reactive T cell clones. Finally, we demonstrate that the same set of foreign and autoreactive CD4 + T cell clones are repetitively generated throughout adulthood. The latter observation argues against T cell-depleting strategies or autologous stem cell transplantation as therapies for autoimmunity-as the immune system has the ability to regenerate pathogenic clones. Published by

  15. Human papilloma virus-specific T cells can be generated from naïve T cells for use as an immunotherapeutic strategy for immunocompromised patients.

    PubMed

    McCormack, Sarah E; Cruz, Conrad Russell Y; Wright, Kaylor E; Powell, Allison B; Lang, Haili; Trimble, Cornelia; Keller, Michael D; Fuchs, Ephraim; Bollard, Catherine M

    2018-03-01

    Human papilloma virus (HPV) is a known cause of cervical cancer, squamous cell carcinoma and laryngeal cancer. Although treatments exist for HPV-associated malignancies, patients unresponsive to these therapies have a poor prognosis. Recent findings from vaccine studies suggest that T-cell immunity is essential for disease control. Because Epstein-Barr Virus (EBV)-specific T cells have been highly successful in treating or preventing EBV-associated tumors, we hypothesized that the development of a manufacturing platform for HPV-specific T cells from healthy donors could be used in a third-party setting to treat patients with high-risk/relapsed HPV-associated cancers. Most protocols for generating virus-specific T cells require prior exposure of the donor to the targeted virus and, because the seroprevalence of high-risk HPV types varies greatly by age and ethnicity, manufacturing of donor-derived HPV-specific T cells has proven challenging. We, therefore, made systematic changes to our current Good Manufacturing Practice (GMP)-compliant protocols to improve antigen presentation, priming and expansion for the manufacture of high-efficacy HPV-specific T cells. Like others, we found that current methodologies fail to expand HPV-specific T cells from most healthy donors. By optimizing dendritic cell maturation and function with lipopolysaccharide (LPS) and interferon (IFN)γ, adding interleukin (IL)-21 during priming and depleting memory T cells, we achieved reliable expansion of T cells specific for oncoproteins E6 and E7 to clinically relevant amounts (mean, 578-fold expansion; n = 10), which were polyfunctional based on cytokine multiplex analysis. In the third-party setting, such HPV-specific T-cell products might serve as a potent salvage therapy for patients with HPV-associated diseases. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  16. RUNX1 promotes cell growth in human T-cell acute lymphoblastic leukemia by transcriptional regulation of key target genes.

    PubMed

    Jenkins, Catherine E; Gusscott, Samuel; Wong, Rachel J; Shevchuk, Olena O; Rana, Gurneet; Giambra, Vincenzo; Tyshchenko, Kateryna; Islam, Rashedul; Hirst, Martin; Weng, Andrew P

    2018-05-04

    RUNX1 is frequently mutated in T-cell acute lymphoblastic leukemia (T-ALL). The spectrum of RUNX1 mutations has led to the notion that it acts as a tumor suppressor in this context; however, other studies have placed RUNX1 along with transcription factors TAL1 and NOTCH1 as core drivers of an oncogenic transcriptional program. To reconcile these divergent roles, we knocked down RUNX1 in human T-ALL cell lines and deleted Runx1 or Cbfb in primary mouse T-cell leukemias. RUNX1 depletion consistently resulted in reduced cell proliferation and increased apoptosis. RUNX1 upregulated variable sets of target genes in each cell line, but consistently included a core set of oncogenic effectors including IGF1R and NRAS. Our results support the conclusion that RUNX1 has a net positive effect on cell growth in the context of established T-ALL. Copyright © 2018. Published by Elsevier Inc.

  17. Auranofin induces apoptosis and necrosis in HeLa cells via oxidative stress and glutathione depletion.

    PubMed

    You, Bo Ra; Shin, Hye Rim; Han, Bo Ram; Kim, Suhn Hee; Park, Woo Hyun

    2015-02-01

    Auranofin (Au), an inhibitor of thioredoxin reductase, is a known anti‑cancer drug. In the present study, the anti‑growth effect of Au on HeLa cervical cancer cells was examined in association with levels of reactive oxygen species (ROS) and glutathione (GSH). Au inhibited the growth of HeLa cells with an IC50 of ~2 µM at 24 h. This agent induced apoptosis and necrosis, accompanied by the cleavage of poly (ADP‑ribose) polymerase and loss of mitochondrial membrane potential. The pan‑caspase inhibitor, benzyloxycarbonyl‑Val‑Ala‑Asp‑fluoromethylketone, prevented apoptotic cell death and each of the assessed caspase inhibitors inhibited necrotic cell death induced by Au. With respect to the levels of ROS and GSH, Au increased intracellular O2•- in the HeLa cells and induced GSH depletion. The pan‑caspase inhibitor reduced the levels of O2•- and GSH depletion in Au‑treated HeLa cells. The antioxidant, N‑acetyl cysteine, not only attenuated apoptosis and necrosis in the Au‑treated HeLa cells, but also decreased the levels of O2•- and GSH depletion in the cells. By contrast, L‑buthionine sulfoximine, a GSH synthesis inhibitor, intensified cell death O2•- and GSH depletion in the Au‑treated HeLa cells. In conclusion, Au induced apoptosis and necrosis in HeLa cells via the induction of oxidative stress and the depletion of GSH.

  18. CD4+ CD25+ Regulatory T Cells Impair HIV-1-Specific CD4 T Cell Responses by Upregulating Interleukin-10 Production in Monocytes

    PubMed Central

    Kwon, Douglas S.; Angin, Mathieu; Hongo, Tomoyuki; Law, Kenneth M.; Johnson, Jessica; Porichis, Filippos; Hart, Meghan G.; Pavlik, David F.; Tighe, Daniel P.; Kavanagh, Daniel G.; Streeck, Hendrik; Addo, Marylyn M.

    2012-01-01

    T cell dysfunction in the presence of ongoing antigen exposure is a cardinal feature of chronic viral infections with persistent high viremia, including HIV-1. Although interleukin-10 (IL-10) has been implicated as an important mediator of this T cell dysfunction, the regulation of IL-10 production in chronic HIV-1 infection remains poorly understood. We demonstrated that IL-10 is elevated in the plasma of individuals with chronic HIV-1 infection and that blockade of IL-10 signaling results in a restoration of HIV-1-specific CD4 T cell proliferation, gamma interferon (IFN-γ) secretion, and, to a lesser extent, IL-2 production. Whereas IL-10 blockade leads to restoration of IFN-γ secretion by HIV-1-specific CD4 T cells in all categories of subjects investigated, significant enhancement of IL-2 production and improved proliferation of CD4 T helper cells are restricted to viremic individuals. In peripheral blood mononuclear cells (PBMCs), this IL-10 is produced primarily by CD14+ monocytes, but its production is tightly controlled by regulatory T cells (Tregs), which produce little IL-10 directly. When Tregs are depleted from PBMCs of viremic individuals, the effect of the IL-10 signaling blockade is abolished and IL-10 production by monocytes decreases, while the production of proinflammatory cytokines, such as tumor necrosis factor alpha (TNF-α), increases. The regulation of IL-10 by Tregs appears to be mediated primarily by contact or paracrine-dependent mechanisms which involve IL-27. This work describes a novel mechanism by which regulatory T cells control IL-10 production and contribute to dysfunctional HIV-1-specific CD4 T cell help in chronic HIV-1 infection and provides a unique mechanistic insight into the role of regulatory T cells in immune exhaustion. PMID:22496237

  19. Depletion of cutaneous macrophages and dendritic cells promotes growth of basal cell carcinoma in mice.

    PubMed

    König, Simone; Nitzki, Frauke; Uhmann, Anja; Dittmann, Kai; Theiss-Suennemann, Jennifer; Herrmann, Markus; Reichardt, Holger M; Schwendener, Reto; Pukrop, Tobias; Schulz-Schaeffer, Walter; Hahn, Heidi

    2014-01-01

    Basal cell carcinoma (BCC) belongs to the group of non-melanoma skin tumors and is the most common tumor in the western world. BCC arises due to mutations in the tumor suppressor gene Patched1 (Ptch). Analysis of the conditional Ptch knockout mouse model for BCC reveals that macrophages and dendritic cells (DC) of the skin play an important role in BCC growth restraining processes. This is based on the observation that a clodronate-liposome mediated depletion of these cells in the tumor-bearing skin results in significant BCC enlargement. The depletion of these cells does not modulate Ki67 or K10 expression, but is accompanied by a decrease in collagen-producing cells in the tumor stroma. Together, the data suggest that cutaneous macrophages and DC in the tumor microenvironment exert an antitumor effect on BCC.

  20. Regulation of gonadotropin receptors on cultured porcine Leydig and Sertoli cells: effect of potassium depletion.

    PubMed

    Bernier, M; Laferrere, B; Jaillard, C; Clerget, M; Saez, J M

    1986-06-01

    We have examined the role of the NaK-ATPase pump activity on the ligand-induced down-regulation of gonadotropin receptors in cultured porcine Leydig and Sertoli cells. In both cells, inhibition of the NaK pump by ouabain produced a depletion of intracellular K+ levels (ID50, 10(-7) M) after a lag period of about 8 h. In the absence of ligand, the number of FSH receptors in ouabain-treated Sertoli cells was unaffected or slightly reduced, whereas a 2-fold increase in the number of human CG (hCG)/LH receptors with small changes in the binding affinity was observed in Leydig cells treated by ouabain. The effect of ouabain was dose dependent. Differences were also observed in the down-regulation process of gonadotropin receptors in ouabain-treated cells. The hCG-induced receptor loss in Leydig cells was completely reversed by ouabain whereas the drug had no effect on ligand-induced loss of FSH receptors in Sertoli cells. Similar results were observed when the cells were incubated in K+-free medium. Kinetics studies with labeled hCG have shown that ouabain treatment slows down significantly the rate of [125I]iodo-hCG internalization (t 1/2, 18 h; control cells, t 1/2, 6 h), but had no effect on the degradation of internalized hormone. The internalization of receptor-bound [125I]iodo-hCG was also reduced when Leydig cells were incubated in K+-free medium, but was restored when this medium was supplemented with rubidium. The influence of the NaK pump on the receptor regulation of a ligand common to both types of cells, such as epidermal growth factor, was studied under the same experimental conditions. Neither ouabain nor K+-free medium were able to prevent the epidermal growth factor-induced reduction of receptor levels in Leydig and Sertoli cells. Thus, it appears that modulation of ligand-induced receptor loss by depletion of cellular K+ levels is not dependent on the cell type, but on the ligand-receptor complex. The data also show a striking difference in the

  1. Dendritic Cells Program Non-Immunogenic Prostate-Specific T Cell Responses Beginning at Early Stages of Prostate Tumorigenesis

    PubMed Central

    Mihalyo, Marianne A.; Hagymasi, Adam T.; Slaiby, Aaron M.; Nevius, Erin E.; Adler, Adam J.

    2010-01-01

    BACKGROUND Prostate cancer promotes the development of T cell tolerance towards prostatic antigens, potentially limiting the efficacy of prostate cancer vaccines targeting these antigens. Here, we sought to determine the stage of disease progression when T cell tolerance develops, as well as the role of steady state dendritic cells (DC) and CD4+CD25+ T regulatory cells (Tregs) in programming tolerance. METHODS The response of naïve HA-specific CD4+ T cells were analyzed following adoptive transfer into Pro-HA × TRAMP transgenic mice harboring variably-staged HA-expressing prostate tumors on two genetic backgrounds that display different patterns and kinetics of tumorigenesis. The role of DC and Tregs in programming HA-specific CD4 cell responses were assessed via depletion. RESULTS HA-specific CD4 cells underwent non-immunogenic responses at all stages of tumorigenesis in both genetic backgrounds. These responses were completely dependent on DC, but not appreciably influenced by Tregs. CONCLUSIONS These results suggest that tolerogenicity is an early and general property of prostate tumors. PMID:17221844

  2. Acute dyskerin depletion triggers cellular senescence and renders osteosarcoma cells resistant to genotoxic stress-induced apoptosis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lin, Ping; Mobasher, Maral E.; Alawi, Faizan, E-mail: falawi@upenn.edu

    Highlights: • Dyskerin depletion triggers cellular senescence in U2OS osteosarcoma cells. • Dyskerin-depleted cells are resistant to apoptosis induced by genotoxic stress. • Chromatin relaxation sensitizes dyskerin-depleted cells to apoptosis. - Abstract: Dyskerin is a conserved, nucleolar RNA-binding protein implicated in an increasing array of fundamental cellular processes. Germline mutation in the dyskerin gene (DKC1) is the cause of X-linked dyskeratosis congenita (DC). Conversely, wild-type dyskerin is overexpressed in sporadic cancers, and high-levels may be associated with poor prognosis. It was previously reported that acute loss of dyskerin function via siRNA-mediated depletion slowed the proliferation of transformed cell lines. However,more » the mechanisms remained unclear. Using human U2OS osteosarcoma cells, we show that siRNA-mediated dyskerin depletion induced cellular senescence as evidenced by proliferative arrest, senescence-associated heterochromatinization and a senescence-associated molecular profile. Senescence can render cells resistant to apoptosis. Conversely, chromatin relaxation can reverse the repressive effects of senescence-associated heterochromatinization on apoptosis. To this end, genotoxic stress-induced apoptosis was suppressed in dyskerin-depleted cells. In contrast, agents that induce chromatin relaxation, including histone deacetylase inhibitors and the DNA intercalator chloroquine, sensitized dyskerin-depleted cells to apoptosis. Dyskerin is a core component of the telomerase complex and plays an important role in telomere homeostasis. Defective telomere maintenance resulting in premature senescence is thought to primarily underlie the pathogenesis of X-linked DC. Since U2OS cells are telomerase-negative, this leads us to conclude that loss of dyskerin function can also induce cellular senescence via mechanisms independent of telomere shortening.« less

  3. Targeted depletion of a MDSC subset unmasks pancreatic ductal adenocarcinoma to adaptive immunity

    PubMed Central

    Stromnes, Ingunn M.; Brockenbrough, Scott; Izeradjene, Kamel; Carlson, Markus A.; Cuevas, Carlos; Simmons, Randi M.; Greenberg, Philip D.; Hingorani, Sunil R.

    2015-01-01

    Objective Pancreatic ductal adenocarcinoma (PDA) is characterized by a robust desmoplasia, including the notable accumulation of immunosuppressive cells that shield neoplastic cells from immune detection. Immune evasion may be further enhanced if the malignant cells fail to express high levels of antigens that are sufficiently immunogenic to engender an effector T cell response. In this report, we investigate the predominant subsets of immunosuppressive cancer-conditioned myeloid cells that chronicle and shape pancreas cancer progression. We show that selective depletion of one subset of myeloid-derived suppressor cells (MDSC) in an autochthonous, genetically engineered mouse model (GEMM) of PDA unmasks the ability of the adaptive immune response to engage and target tumor epithelial cells. Methods A combination of in vivo and in vitro studies were performed employing a GEMM that faithfully recapitulates the cardinal features of human PDA. The predominant cancer-conditioned myeloid cell subpopulation was specifically targeted in vivo and the biological outcomes determined. Results PDA orchestrates the induction of distinct subsets of cancer-associated myeloid cells through the production of factors known to influence myelopoeisis. These immature myeloid cells inhibit the proliferation and induce apoptosis of activated T cells. Targeted depletion of granulocytic MDSC (Gr-MDSC) in autochthonous PDA increases the intratumoral accumulation of activated CD8 T cells and apoptosis of tumor epithelial cells, and also remodels the tumor stroma. Conclusions Neoplastic ductal cells of the pancreas induce distinct myeloid cell subsets that promote tumor cell survival and accumulation. Targeted depletion of a single myeloid subset, the Gr-MDSC, can unmask an endogenous T cell response, revealing an unexpected latent immunity and invoking targeting of Gr-MDSC as a potential strategy to exploit for treating this highly lethal disease. PMID:24555999

  4. Radiation-induced equilibrium is a balance between tumor cell proliferation and T cell-mediated killing

    PubMed Central

    Liang, Hua; Deng, Liufu; Chmura, Steven; Burnette, Byron; Liadis, Nicole; Darga, Thomas; Beckett, Michael A.; Lingen, Mark W.; Witt, MaryEllyn; Weichselbaum, Ralph R.; Fu, Yang-Xin

    2013-01-01

    Local failures following radiation therapy are multifactorial and the contributions of the tumor and the host are complex. Current models of tumor equilibrium suggest that a balance exists between cell birth and cell death due to insufficient angiogenesis, immune effects, or intrinsic cellular factors. We investigated whether host immune responses contribute to radiation induced tumor equilibrium in animal models. We report an essential role for immune cells and their cytokines in suppressing tumor cell regrowth in two experimental animal model systems. Depletion of T cells or neutralization of interferon-gamma reversed radiation-induced equilibrium leading to tumor regrowth. We also demonstrate that PD-L1 blockade augments T cell responses leading to rejection of tumors in radiation induced equilibrium. We identify an active interplay between tumor cells and immune cells that occurs in radiation-induced tumor equilibrium and suggest a potential role for disruption of the PD-L1/PD-1 axis in increasing local tumor control. PMID:23630355

  5. Protection of ATP-depleted cells by impermeant strychnine derivatives: implications for glycine cytoprotection.

    PubMed

    Dong, Z; Venkatachalam, M A; Weinberg, J M; Saikumar, P; Patel, Y

    2001-03-01

    Glycine and structurally related amino acids with activities at chloride channel receptors in the central nervous system also have robust protective effects against cell injury by ATP depletion. The glycine receptor antagonist strychnine shares this protective activity. An essential step toward identification of the molecular targets for these compounds is to determine whether they protect cells through interactions with intracellular targets or with molecules on the outer surface of plasma membranes. Here we report cytoprotection by a cell-impermeant derivative of strychnine. A strychnine-fluorescein conjugate (SF) was synthesized, and impermeability of plasma membranes to this compound was verified by fluorescence confocal microscopy. In an injury model of Madin-Darby canine kidney cells, ATP depletion led to lactate dehydrogenase release. SF prevented lactate dehydrogenase leakage without ameliorating ATP depletion. This was accompanied by preservation of cellular ultrastructure and exclusion of vital dyes. SF protection was also shown for ATP-depleted rat hepatocytes. On the other hand, when a key structural motif in the active site of strychnine was chemically blocked, the SF lost its protective effect, establishing strychnine-related specificity for SF protection. Cytoprotective effects of the cell-impermeant strychnine derivative provide compelling evidence suggesting that molecular targets on the outer surface of plasma membranes may mediate cytoprotection by strychnine and glycine.

  6. Relationship of BK polyoma virus (BKV) in the urine with hemorrhagic cystitis and renal function in recipients of T-cell depleted peripheral blood and cord blood stem cell transplants

    PubMed Central

    Lee, Yeon Joo; Zheng, Junting; Kolitsopoulos, Yovanna; Chung, Dick; Amigues, Isabelle; Son, Tammy; Choo, Kathleen; Hester, Jeff; Giralt, Sergio A.; Glezerman, Ilya G.; Jakubowski, Ann A.; Papanicolaou, Genovefa A.

    2014-01-01

    Hematopoietic stem cell transplant (HSCT) recipients are at significant risk for BKV reactivation, hemorrhagic cystitis (HC) and renal dysfunction. We prospectively monitored 98 HSCT by serial BKV PCR in the urine through Day (D) +100 to analyze the relationship between BKV viruria and HC, serum creatinine (Cr) and creatinine clearance (CrCl) through D +180 or death. Patients, median age 52 years, range 20-73, received T-cell depleted (50%) or cord blood allografts (21%). Median pre-HSCT BKV IgG titers were 1:10,240. Incremental increase in BKV IgG titers correlated with developing BKV viruria ≥ 107 copies/mL. By D +100, 53 (54%) patients had BKV viruria. BKV viral load in the urine increased at engraftment and persisted throughout D +100. HC developed in 10 patients (10%); 7/10 with BKV viruria. In competing risk analyses, BKV viruria ≥ 107 copies/mL, older age, CMV reactivation and foscarnet use were risk factors for HC. Cr and CrCl at 2, 3 and 6 months post-HSCT were similar between patients with and without BKV viruria. PMID:24769326

  7. Neutrophil trails guide influenza-specific CD8⁺ T cells in the airways.

    PubMed

    Lim, Kihong; Hyun, Young-Min; Lambert-Emo, Kris; Capece, Tara; Bae, Seyeon; Miller, Richard; Topham, David J; Kim, Minsoo

    2015-09-04

    During viral infections, chemokines guide activated effector T cells to infection sites. However, the cells responsible for producing these chemokines and how such chemokines recruit T cells are unknown. Here, we show that the early recruitment of neutrophils into influenza-infected trachea is essential for CD8(+) T cell-mediated immune protection in mice. We observed that migrating neutrophils leave behind long-lasting trails that are enriched in the chemokine CXCL12. Experiments with granulocyte-specific CXCL12 conditionally depleted mice and a CXCR4 antagonist revealed that CXCL12 derived from neutrophil trails is critical for virus-specific CD8(+) T cell recruitment and effector functions. Collectively, these results suggest that neutrophils deposit long-lasting, chemokine-containing trails, which may provide both chemotactic and haptotactic cues for efficient CD8(+) T cell migration and localization in influenza-infected tissues. Copyright © 2015, American Association for the Advancement of Science.

  8. Dietary Restriction and Fasting Arrest B and T Cell Development and Increase Mature B and T Cell Numbers in Bone Marrow

    PubMed Central

    Shushimita, Shushimita; de Bruijn, Marjolein J. W.; de Bruin, Ron W. F.; IJzermans, Jan N. M.; Hendriks, Rudi W.; Dor, Frank J. M. F.

    2014-01-01

    Dietary restriction (DR) delays ageing and extends life span. Both long- and short-term DR, as well as short-term fasting provide robust protection against many “neuronal and surgery related damaging phenomena” such as Parkinson’s disease and ischemia-reperfusion injury. The exact mechanism behind this phenomenon has not yet been elucidated. Its anti-inflammatory actions prompted us to thoroughly investigate the consequences of DR and fasting on B and T cell compartments in primary and secondary lymphoid organs of male C57Bl/6 mice. In BM we found that DR and fasting cause a decrease in the total B cell population and arrest early B cell development, while increasing the number of recirculating mature B cells. In the fasting group, a significant reduction in peripheral B cell counts was observed in both spleen and mesenteric lymph nodes (mLN). Thymopoiesis was arrested significantly at double negative DN2 stage due to fasting, whereas DR resulted in a partial arrest of thymocyte development at the DN4 stage. Mature CD3+ T cell populations were increased in BM and decreased in both spleen and mLN. Thus, DR arrests B cell development in the BM but increases the number of recirculating mature B cells. DR also arrests maturation of T cells in thymus, resulting in depletion of mature T cells from spleen and mLN while recruiting them to the BM. The functional relevance in relation to protection against organ damage needs to be determined. PMID:24504160

  9. HIV-1 alters the cytokine microenvironment and effector function of CD8+T cells upon antigen-specific activation with mycobacteria

    USDA-ARS?s Scientific Manuscript database

    Tuberculosis is the most common opportunistic infection in individuals living with human immunodeficiency virus (HIV). In addition to CD4+ T cell depletion, HIV infection compromises the function of CD8+ T cell-mediated immunity to Mycobacterium tuberculosis (M.tb). These effects on susceptibility ...

  10. Rituximab, B-lymphocyte depletion, and preservation of beta-cell function.

    PubMed

    Pescovitz, Mark D; Greenbaum, Carla J; Krause-Steinrauf, Heidi; Becker, Dorothy J; Gitelman, Stephen E; Goland, Robin; Gottlieb, Peter A; Marks, Jennifer B; McGee, Paula F; Moran, Antoinette M; Raskin, Philip; Rodriguez, Henry; Schatz, Desmond A; Wherrett, Diane; Wilson, Darrell M; Lachin, John M; Skyler, Jay S

    2009-11-26

    The immunopathogenesis of type 1 diabetes mellitus is associated with T-lymphocyte autoimmunity. However, there is growing evidence that B lymphocytes play a role in many T-lymphocyte-mediated diseases. It is possible to achieve selective depletion of B lymphocytes with rituximab, an anti-CD20 monoclonal antibody. This phase 2 study evaluated the role of B-lymphocyte depletion in patients with type 1 diabetes. We conducted a randomized, double-blind study in which 87 patients between 8 and 40 years of age who had newly diagnosed type 1 diabetes were assigned to receive infusions of rituximab or placebo on days 1, 8, 15, and 22 of the study. The primary outcome, assessed 1 year after the first infusion, was the geometric mean area under the curve (AUC) for the serum C-peptide level during the first 2 hours of a mixed-meal tolerance test. Secondary outcomes included safety and changes in the glycated hemoglobin level and insulin dose. At 1 year, the mean AUC for the level of C peptide was significantly higher in the rituximab group than in the placebo group. The rituximab group also had significantly lower levels of glycated hemoglobin and required less insulin. Between 3 months and 12 months, the rate of decline in C-peptide levels in the rituximab group was significantly less than that in the placebo group. CD19+ B lymphocytes were depleted in patients in the rituximab group, but levels increased to 69% of baseline values at 12 months. More patients in the rituximab group than in the placebo group had adverse events, mostly grade 1 or grade 2, after the first infusion. The reactions appeared to be minimal with subsequent infusions. There was no increase in infections or neutropenia with rituximab. A four-dose course of rituximab partially preserved beta-cell function over a period of 1 year in patients with type 1 diabetes. The finding that B lymphocytes contribute to the pathogenesis of type 1 diabetes may open a new pathway for exploration in the treatment of

  11. Total Recall: Can We Reshape T Cell Memory by Lymphoablation?

    PubMed

    Nicosia, M; Valujskikh, A

    2017-07-01

    Despite recent advances in immunosuppression, donor-reactive memory T cells remain a serious threat to successful organ transplantation. To alleviate damaging effects of preexisting immunologic memory, lymphoablative induction therapies are used as part of standard care in sensitized recipients. However, accumulating evidence suggests that memory T cells have advantages over their naive counterparts in surviving depletion and expanding under lymphopenic conditions. This may at least partially explain the inability of existing lymphoablative strategies to improve long-term allograft outcome in sensitized recipients, despite the well-documented decrease in the frequency of early acute rejection episodes. This minireview summarizes the insights gained from both experimental and clinical transplantation as to the effects of existing lymphoablative strategies on memory T cells and discusses the latest research developments aimed at improving the efficacy and safety of lymphoablation. © 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.

  12. Immature Renal Dendritic Cells Recruit Regulatory CXCR6+ Invariant Natural Killer T Cells to Attenuate Crescentic GN

    PubMed Central

    Riedel, Jan-Hendrik; Paust, Hans-Joachim; Turner, Jan-Eric; Tittel, André P.; Krebs, Christian; Disteldorf, Erik; Wegscheid, Claudia; Tiegs, Gisa; Velden, Joachim; Mittrücker, Hans-Willi; Garbi, Natalio; Stahl, Rolf A.K.; Steinmetz, Oliver M.; Kurts, Christian

    2012-01-01

    Immature renal dendritic cells (DCs) are protective early in murine crescentic GN, but the mechanisms underlying this protection are unknown. Here, depletion of DCs reduced the recruitment of invariant natural killer T (iNKT) cells, which attenuate GN, into the kidney in the early stage of experimental crescentic GN. More than 90% of renal iNKT cells expressed the chemokine receptor CXCR6, and renal DCs produced high amounts of the cognate ligand CXCL16 early after induction of nephritis, suggesting that renal DC-derived CXCL16 might attract protective CXCR6+ iNKT cells. Consistent with this finding, CXCR6-deficient mice exhibited less iNKT cell recruitment and developed nephritis that was more severe, similar to the aggravated nephritis observed in mice depleted of immature DCs. Finally, adoptive transfer of CXCR6-competent NKT cells ameliorated nephritis. Taken together, these results suggest an immunoprotective mechanism involving immature DCs, CXCL16, CXCR6, and regulatory iNKT cells, which might stimulate the development of new therapeutic strategies for GN. PMID:23138484

  13. Immature renal dendritic cells recruit regulatory CXCR6(+) invariant natural killer T cells to attenuate crescentic GN.

    PubMed

    Riedel, Jan-Hendrik; Paust, Hans-Joachim; Turner, Jan-Eric; Tittel, André P; Krebs, Christian; Disteldorf, Erik; Wegscheid, Claudia; Tiegs, Gisa; Velden, Joachim; Mittrücker, Hans-Willi; Garbi, Natalio; Stahl, Rolf A K; Steinmetz, Oliver M; Kurts, Christian; Panzer, Ulf

    2012-12-01

    Immature renal dendritic cells (DCs) are protective early in murine crescentic GN, but the mechanisms underlying this protection are unknown. Here, depletion of DCs reduced the recruitment of invariant natural killer T (iNKT) cells, which attenuate GN, into the kidney in the early stage of experimental crescentic GN. More than 90% of renal iNKT cells expressed the chemokine receptor CXCR6, and renal DCs produced high amounts of the cognate ligand CXCL16 early after induction of nephritis, suggesting that renal DC-derived CXCL16 might attract protective CXCR6(+) iNKT cells. Consistent with this finding, CXCR6-deficient mice exhibited less iNKT cell recruitment and developed nephritis that was more severe, similar to the aggravated nephritis observed in mice depleted of immature DCs. Finally, adoptive transfer of CXCR6-competent NKT cells ameliorated nephritis. Taken together, these results suggest an immunoprotective mechanism involving immature DCs, CXCL16, CXCR6, and regulatory iNKT cells, which might stimulate the development of new therapeutic strategies for GN.

  14. Feasibility and Outcome of Haploidentical Hematopoietic Stem Cell Transplantation with Post-Transplant High-Dose Cyclophosphamide for Children and Adolescents with Hematologic Malignancies: An AIEOP-GITMO Retrospective Multicenter Study.

    PubMed

    Berger, Massimo; Lanino, Edoardo; Cesaro, Simone; Zecca, Marco; Vassallo, Elena; Faraci, Maura; De Bortoli, Massimiliano; Barat, Veronica; Prete, Arcangelo; Fagioli, Franca

    2016-05-01

    Post-transplant high-dose cyclophosphamide (PTCy) is a novel approach to prevent graft-versus-host disease (GVHD) and rejection in patients given haploidentical hematopoietic stem cell transplantation (HSCT). Thirty-three patients with high-risk hematologic malignancies and lacking a match-related or -unrelated donor were treated with PTCy haploidentical HSCT in 5 Italian AIEOP centers. Nineteen patients had a nonmyeloablative preparative regimen (57%), and 14 patients received a full myeloablative conditioning regimen (43%). No patients received serotherapy; GVHD prophylaxis was based on PTCy (50 mg/kg on days +3 and +4) combined with mycophenolate plus tacrolimus or cyclosporine A. Neutrophil and platelet engraftment was achieved on days +17 (range, 14 to 37) and +27 (range, 16 to 71). One patient had autologous reconstitution for anti-HLA antibodies. Acute GVHD grades II to IV and III to IV and chronic GVHD developed in 22% (95% CI, 11 to 42), 3% (95% CI, 0 to 21), and 4% (95% CI, 0 to 27) of cases, respectively. The 1-year overall survival rate was 72% (95% CI, 56 to 88), progression-free survival rate was 61% (95% CI, 43 to 80), cumulative incidence of relapse was 24% (95% CI, 13 to 44), and transplant-related mortality was 9% (95% CI, 3 to 26). The univariate analysis for risk of relapse incidence showed how 3 significant variables, mother as donor (P = .02), donor gender as female (P = .04), and patient gender as female (P = .02), were significantly associated with a lower risk of relapse. Disease progression was the main cause of death. PTCy is a safe procedure also for children and adolescents who have already received several lines of chemotherapy. Among the different diseases, a trend for better 1-year rates of overall survival was obtained for nonacute leukemia patients. Copyright © 2016 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  15. Opioid maintenance therapy restores CD4+ T cell function by normalizing CD4+CD25(high) regulatory T cell frequencies in heroin user.

    PubMed

    Riss, Gina-Lucia; Chang, Dae-In; Wevers, Carolin; Westendorf, Astrid M; Buer, Jan; Scherbaum, Norbert; Hansen, Wiebke

    2012-08-01

    There is an increasing body of evidence that heroin addiction is associated with severe alterations in immune function, which might contribute to an increased risk to contract infectious diseases like hepatitis B and C or HIV. However, the impact of heroin consumption on the CD4(+) T cell compartment is not well understood. Therefore, we analyzed the frequency and functional phenotype of CD4(+) T cells as well as immune-suppressive CD4(+)CD25(high) regulatory T cells (Tregs) isolated from the peripheral blood of opiate addicts currently abusing heroin (n=27) in comparison to healthy controls (n=25) and opiate addicts currently in opioid maintenance treatment (OMT; n=27). Interestingly, we detected a significant increase in the percentage of CD4(+)CD25(high) Tregs in the peripheral blood of heroin addicted patients in contrast to patients in OMT. The proliferative response of CD4(+) T cells upon stimulation with anti-CD3 and anti-CD28 antibodies was significantly decreased in heroin users, but could be restored by depletion of CD25(high) regulatory T cells from CD4(+) T cells to similar values as observed from healthy controls and patients in OMT. These results suggest that impaired immune responses observed in heroin users are related to the expansion of CD4(+)CD25(high) Tregs and more importantly, can be restored by OMT. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Regulatory T Cells in Skin Facilitate Epithelial Stem Cell Differentiation.

    PubMed

    Ali, Niwa; Zirak, Bahar; Rodriguez, Robert Sanchez; Pauli, Mariela L; Truong, Hong-An; Lai, Kevin; Ahn, Richard; Corbin, Kaitlin; Lowe, Margaret M; Scharschmidt, Tiffany C; Taravati, Keyon; Tan, Madeleine R; Ricardo-Gonzalez, Roberto R; Nosbaum, Audrey; Bertolini, Marta; Liao, Wilson; Nestle, Frank O; Paus, Ralf; Cotsarelis, George; Abbas, Abul K; Rosenblum, Michael D

    2017-06-01

    The maintenance of tissue homeostasis is critically dependent on the function of tissue-resident immune cells and the differentiation capacity of tissue-resident stem cells (SCs). How immune cells influence the function of SCs is largely unknown. Regulatory T cells (Tregs) in skin preferentially localize to hair follicles (HFs), which house a major subset of skin SCs (HFSCs). Here, we mechanistically dissect the role of Tregs in HF and HFSC biology. Lineage-specific cell depletion revealed that Tregs promote HF regeneration by augmenting HFSC proliferation and differentiation. Transcriptional and phenotypic profiling of T regs and HFSCs revealed that skin-resident Tregs preferentially express high levels of the Notch ligand family member, Jagged 1 (Jag1). Expression of Jag1 on Tregs facilitated HFSC function and efficient HF regeneration. Taken together, our work demonstrates that Tregs in skin play a major role in HF biology by promoting the function of HFSCs. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Internalization of Rituximab and the Efficiency of B Cell Depletion in Rheumatoid Arthritis and Systemic Lupus Erythematosus

    PubMed Central

    Cambridge, Geraldine; Isenberg, David A.; Glennie, Martin J.; Cragg, Mark S.; Leandro, Maria

    2015-01-01

    Objective Rituximab, a type I anti‐CD20 monoclonal antibody (mAb), induces incomplete B cell depletion in some patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), thus contributing to a poor clinical response. The mechanisms of this resistance remain elusive. The purpose of this study was to determine whether type II mAb are more efficient than type I mAb at depleting B cells from RA and SLE patients, whether internalization influences the efficiency of depletion, and whether Fcγ receptor type IIb (FcγRIIb) and the B cell receptor regulate this internalization process. Methods We used an in vitro whole blood B cell–depletion assay to assess the efficiency of depletion, flow cytometry to study cell surface protein expression, and surface fluorescence–quenching assays to assess rituximab internalization, in samples from patients with RA and patients with SLE. Paired t‐test or Mann‐Whitney U test was used to compare groups, and Spearman's rank correlation test was used to assess correlation. Results We found that type II mAb internalized significantly less rituximab than type I mAb and depleted B cells from patients with RA and SLE at least 2‐fold more efficiently than type I mAb. Internalization of rituximab was highly variable between patients, was regulated by FcγRIIb, and inversely correlated with cytotoxicity in whole blood B cell–depletion assays. The lowest levels of internalization were seen in IgD– B cells, including postswitched (IgD–CD27+) memory cells. Internalization of type I anti‐CD20 mAb was also partially inhibited by anti‐IgM stimulation. Conclusion Variability in internalization of rituximab was observed and was correlated with impaired B cell depletion. Therefore, slower‐internalizing type II mAb should be considered as alternative B cell–depleting agents for the treatment of RA and SLE. PMID:25916583

  18. Cytotoxic human peripheral blood-derived γδT cells kill glioblastoma cell lines: implications for cell-based immunotherapy for patients with glioblastoma.

    PubMed

    Nakazawa, Tsutomu; Nakamura, Mitsutoshi; Park, Young Soo; Motoyama, Yasushi; Hironaka, Yasuo; Nishimura, Fumihiko; Nakagawa, Ichiro; Yamada, Shuichi; Matsuda, Ryosuke; Tamura, Kentaro; Sugimoto, Tadashi; Takeshima, Yasuhiro; Marutani, Akiko; Tsujimura, Takahiro; Ouji, Noriko; Ouji, Yukiteru; Yoshikawa, Masahide; Nakase, Hiroyuki

    2014-01-01

    Glioblastoma (GBM) is a highly aggressive brain tumor for which novel therapeutic approaches, such as immunotherapy, are urgently needed. Zoledronate (ZOL), an inhibitor of osteoclastic activity, is known to stimulate peripheral blood-derived γδT cells and sensitize tumors to γδT cell-mediated killing. To investigate the feasibility of γδT cell-based immunotherapy for patients with GBM, we focused on the killing of GBM cell lines by γδT cells and the molecular mechanisms involved in these cell-cell interactions. Peripheral blood mononuclear cells were expanded in ZOL and interleukin (IL)-2 for 14 days, and γδT cells were enriched in the expanded cells by the immunomagnetic depletion of αβT cells. Gliomas are resistant to NK cells but susceptible to lymphokine-activated killer cells and some cytotoxic T lymphocytes. When the γδT cell-mediated killing of three GBM cell lines (U87MG, U138MG and A172 cells) and an NK-sensitive leukemia cell line (K562 cells) were tested, 32% U87MG, 15% U138MG, 1% A172, and 50% K562 cells were killed at an effector:target ratio of 5:1. The γδT cell-mediated killing of all three GBM cell lines was significantly enhanced by ZOL and this ZOL-enhanced killing was blocked by an anti-T cell receptor (TcR) antibody. These results indicated that TcR γδ is crucial for the recognition of ZOL-treated GBM cells by γδT cells. Since the low level killing of GBM cells by the γδT cells was enhanced by ZOL, γδT cell-targeting therapy in combination with ZOL treatment could be effective for patients with GBM.

  19. Okadaic acid overcomes the blocked cell cycle caused by depleting Cdc2-related kinases in Trypanosoma brucei

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li Ziyin; Tu Xiaoming; Wang, Ching C.

    2006-11-01

    Mitosis and cytokinesis are highly coordinated in eukaryotic cells. But procyclic-form Trypanosoma brucei under G1 or mitotic arrest is still capable of dividing, resulting in anucleate daughter cells (zoids). Okadaic acid (OKA), an inhibitor of protein phosphatases PP1 and PP2A, is known to inhibit kinetoplast replication and cell division yielding multinucleate cells with single kinetoplasts. However, when OKA was applied to cells arrested in G1 or G2/M phase via RNAi knockdown of specific cdc2-related kinases (CRKs), DNA synthesis and nuclear division were resumed without kinetoplast replication or cell division, resulting in multinucleate cells as in the wild type. Cells arrestedmore » in G2/M via depleting the mitotic cyclin CycB2 or an aurora B kinase homologue TbAUK1 were, however, not released by OKA treatment. The phenomenon is thus similar to the OKA activation of Cdc2 in Xenopus oocyte by inhibiting PP2A [Maton, et al., Differential regulation of Cdc2 and Aurora-A in Xenopus oocytes: a crucial role of phosphatase 2A. J. Cell Sci. 118 (2005) 2485-2494]. A simultaneous knockdown of the seven PP1s or the PP2A catalytic subunit in T. brucei by RNA interference did not, however, result in multinucleate cells. This could be explained by assuming a negative regulation, either directly or indirectly, of CRK by an OKA-sensitive phosphatase, which could be a PP2A as in the Xenopus oocyte and a positive regulation of kinetoplast replication by an OKA-susceptible protein(s). Test of a PP2A-specific inhibitor, fostriecin, on cells arrested in G2/M via CRK depletion or a knockdown of the PP2A catalytic subunit from the CRK-depleted cells both showed a partial lift of the G2/M block without forming multinucleate cells. These observations support the abovementioned assumption and suggest the presence of a novel OKA-sensitive protein(s) regulating kinetoplast replication that still remains to be identified.« less

  20. Macrophage depletion and Schwann cell transplantation reduce cyst size after rat contusive spinal cord injury.

    PubMed

    Lee, Yee-Shuan; Funk, Lucy H; Lee, Jae K; Bunge, Mary Bartlett

    2018-04-01

    Schwann cell transplantation is a promising therapy for the treatment of spinal cord injury (SCI) and is currently in clinical trials. In our continuing efforts to improve Schwann cell transplantation strategies, we sought to determine the combined effects of Schwann cell transplantation with macrophage depletion. Since macrophages are major inflammatory contributors to the acute spinal cord injury, and are the major phagocytic cells, we hypothesized that transplanting Schwann cells after macrophage depletion will improve cell survival and integration with host tissue after SCI. To test this hypothesis, rat models of contusive SCI at thoracic level 8 were randomly subjected to macrophage depletion or not. In rat subjected to macrophage depletion, liposomes filled with clodronate were intraperitoneally injected at 1, 3, 6, 11, and 18 days post injury. Rats not subjected to macrophage depletion were intraperitoneally injected with liposomes filled with phosphate buffered saline. Schwann cells were transplanted 1 week post injury in all rats. Biotinylated dextran amine (BDA) was injected at thoracic level 5 to evalute axon regeneration. The Basso, Beattie, and Bresnahan locomotor test, Gridwalk test, and sensory test using von Frey filaments were performed to assess functional recovery. Immunohistochemistry was used to detect glial fibrillary acidic protein, neurofilament, and green fluorescent protein (GFP), and also to visulize BDA-labelled axons. The GFP labeled Schwann cell and cyst and lesion volumes were quantified using stained slides. The numbers of BDA-positive axons were also quantified. At 8 weeks after Schwann cell transplantation, there was a significant reduction in cyst and lesion volumes in the combined treatment group compared to Schwann cell transplantation alone. These changes were not associated, however, with improved Schwann cell survival, axon growth, or locomotor recovery. Although combining Schwann cell transplantation with macrophage

  1. Macrophage depletion and Schwann cell transplantation reduce cyst size after rat contusive spinal cord injury

    PubMed Central

    Lee, Yee-Shuan; Funk, Lucy H.; Lee, Jae K.; Bunge, Mary Bartlett

    2018-01-01

    Schwann cell transplantation is a promising therapy for the treatment of spinal cord injury (SCI) and is currently in clinical trials. In our continuing efforts to improve Schwann cell transplantation strategies, we sought to determine the combined effects of Schwann cell transplantation with macrophage depletion. Since macrophages are major inflammatory contributors to the acute spinal cord injury, and are the major phagocytic cells, we hypothesized that transplanting Schwann cells after macrophage depletion will improve cell survival and integration with host tissue after SCI. To test this hypothesis, rat models of contusive SCI at thoracic level 8 were randomly subjected to macrophage depletion or not. In rat subjected to macrophage depletion, liposomes filled with clodronate were intraperitoneally injected at 1, 3, 6, 11, and 18 days post injury. Rats not subjected to macrophage depletion were intraperitoneally injected with liposomes filled with phosphate buffered saline. Schwann cells were transplanted 1 week post injury in all rats. Biotinylated dextran amine (BDA) was injected at thoracic level 5 to evalute axon regeneration. The Basso, Beattie, and Bresnahan locomotor test, Gridwalk test, and sensory test using von Frey filaments were performed to assess functional recovery. Immunohistochemistry was used to detect glial fibrillary acidic protein, neurofilament, and green fluorescent protein (GFP), and also to visulize BDA-labelled axons. The GFP labeled Schwann cell and cyst and lesion volumes were quantified using stained slides. The numbers of BDA-positive axons were also quantified. At 8 weeks after Schwann cell transplantation, there was a significant reduction in cyst and lesion volumes in the combined treatment group compared to Schwann cell transplantation alone. These changes were not associated, however, with improved Schwann cell survival, axon growth, or locomotor recovery. Although combining Schwann cell transplantation with macrophage

  2. A novel subset of helper T cells promotes immune responses by secreting GM-CSF

    PubMed Central

    Zhang, J; Roberts, A I; Liu, C; Ren, G; Xu, G; Zhang, L; Devadas, S; Shi, Yufang

    2013-01-01

    Helper T cells are crucial for maintaining proper immune responses. Yet, they have an undefined relationship with one of the most potent immune stimulatory cytokines, granulocyte macrophage-colony-stimulating factor (GM-CSF). By depleting major cytokines during the differentiation of CD4+ T cells in vitro, we derived cells that were found to produce large amounts of GM-CSF, but little of the cytokines produced by other helper T subsets. By their secretion of GM-CSF, this novel subset of helper T cells (which we have termed ThGM cells) promoted the production of cytokines by other T-cell subtypes, including type 1 helper T cell (Th1), type 2 helper T cell (Th2), type 1 cytotoxic T cell (Tc1), type 2 cytotoxic T cell (Tc2), and naive T cells, as evidenced by the fact that antibody neutralization of GM-CSF abolished this effect. ThGM cells were found to be highly prone to activation-induced cell death (AICD). Inhibitors of TRAIL or granzymes could not block AICD in ThGM cells, whereas inhibition of FasL/Fas interaction partially rescued ThGM cells from AICD. Thus, ThGM cells are a novel subpopulation of T helper cells that produce abundant GM-CSF, exhibit exquisite susceptibility to apoptosis, and therefore play a pivotal role in the regulation of the early stages of immune responses. PMID:24076588

  3. Depletion of Pax7+ satellite cells does not affect diaphragm adaptations to running in young or aged mice.

    PubMed

    Murach, Kevin A; Confides, Amy L; Ho, Angel; Jackson, Janna R; Ghazala, Lina S; Peterson, Charlotte A; Dupont-Versteegden, Esther E

    2017-10-01

    Satellite cell depletion does not affect diaphragm adaptations to voluntary wheel running in young or aged mice. Satellite cell depletion early in life (4 months of age) has minimal effect on diaphragm phenotype by old age (24 months). Prolonged satellite cell depletion in the diaphragm does not result in excessive extracellular matrix accumulation, in contrast to what has been reported in hind limb muscles. Up-regulation of Pax3 mRNA+ cells after satellite cell depletion in young and aged mice suggests that Pax3+ cells may compensate for a loss of Pax7+ satellite cells in the diaphragm. Future investigations should focus on the role of Pax3+ cells in the diaphragm during adaptation to exercise and ageing. Satellite cell contribution to unstressed diaphragm is higher compared to hind limb muscles, which is probably attributable to constant activation of this muscle to drive ventilation. Whether satellite cell depletion negatively impacts diaphragm quantitative and qualitative characteristics under stressed conditions in young and aged mice is unknown. We therefore challenged the diaphragm with prolonged running activity in the presence and absence of Pax7+ satellite cells in young and aged mice using an inducible Pax7 CreER -R26R DTA model. Mice were vehicle (Veh, satellite cell-replete) or tamoxifen (Tam, satellite cell-depleted) treated at 4 months of age and were then allowed to run voluntarily at 6 months (young) and 22 months (aged). Age-matched, cage-dwelling, Veh- and Tam-treated mice without wheel access served as activity controls. Diaphragm muscles were analysed from young (8 months) and aged (24 months) mice. Satellite cell depletion did not alter diaphragm mean fibre cross-sectional area, fibre type distribution or extracellular matrix content in young or aged mice, regardless of running activity. Resting in vivo diaphragm function was also unaffected by satellite cell depletion. Myonuclear density was maintained in young satellite cell-depleted

  4. Haploidentical hematopoietic transplantation from KIR ligand-mismatched donors with activating KIRs reduces nonrelapse mortality.

    PubMed

    Mancusi, Antonella; Ruggeri, Loredana; Urbani, Elena; Pierini, Antonio; Massei, Maria Speranza; Carotti, Alessandra; Terenzi, Adelmo; Falzetti, Franca; Tosti, Antonella; Topini, Fabiana; Bozza, Silvia; Romani, Luigina; Tognellini, Rita; Stern, Martin; Aversa, Franco; Martelli, Massimo F; Velardi, Andrea

    2015-05-14

    Because activating killer cell immunoglobulinlike receptors (KIRs) are heterogeneously expressed in the population, we investigated the role of donor activating KIRs in haploidentical hematopoietic transplants for acute leukemia. Transplants were grouped according to presence vs absence of KIR-ligand mismatches in the graft-vs-host direction (ie, of donor-vs-recipient natural killer [NK]-cell alloreactivity). In the absence of donor-vs-recipient NK-cell alloreactivity, donor activating KIRs had no effects on outcomes. In the 69 transplant pairs with donor-vs-recipient NK-cell alloreactivity, transplantation from donors with KIR2DS1 and/or KIR3DS1 was associated with reduced risk of nonrelapse mortality, largely infection related (KIR2DS1 present vs absent: hazard ratio [HR], 0.25; P = .01; KIR3DS1 present vs absent: HR, 0.18; P = .006), and better event-free survival (KIR2DS1 present vs absent: HR, 0.31; P = .011; KIR3DS1 present vs absent: HR, 0.30; P = .008). Transplantation from donors with KIR2DS1 and/or KIR3DS1 was also associated with a 50% reduction in infection rate (P = .003). In vitro analyses showed that KIR2DS1 binding to its HLA-C2 ligand upregulated inflammatory cytokine production by alloreactive NK cells in response to infectious challenges. Because ∼40% of donors able to exert donor-vs-recipient NK-cell alloreactivity carry KIR2DS1 and/or KIR3DS1, searching for them may become a feasible, additional criterion in donor selection. © 2015 by The American Society of Hematology.

  5. Control of Cytomegalovirus Viremia after Allogeneic Stem Cell Transplantation: A Review on CMV-Specific T Cell Reconstitution.

    PubMed

    van der Heiden, Pim; Marijt, Erik; Falkenburg, Fred; Jedema, Inge

    2018-04-04

    Recipients of allogeneic stem cell transplantation (alloSCT) are at risk for reactivation of endogenous herpesviruses due to profound and prolonged T cell deficiency following conditions such as graft-versus-host disease, immunosuppression, and/or T cell depletion. Reactivation of endogenous cytomegalovirus (CMV) is the most frequently occurring herpesvirus reactivation following alloSCT. Antiviral medication is often used in pre-emptive treatment strategies initiated when increases in CMV viral loads are detected as a result of active reactivation of the virus. Despite pre-emptive antiviral treatment, the incidence of CMV disease in CMV-seropositive alloSCT patients is still 10% at 1 year following alloSCT. This illustrates the necessity for adequate CMV-specific T cell immunity for long-term control of CMV and prevention of CMV disease. In this review, we analyzed the available studies on the influence of donor CMV status on CMV-specific T cell reconstitution and CMV disease. Furthermore, we reviewed the available studies on the safety and efficacy of adoptive transfer of donor CMV-specific T cells for the prevention and treatment of CMV disease following alloSCT, including studies on adoptive transfer of third-party CMV-specific T cells as a possible alternative when donor T cells are not available. Copyright © 2018 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  6. Regulatory T cells facilitate the nuclear accumulation of inducible cAMP early repressor (ICER) and suppress nuclear factor of activated T cell c1 (NFATc1)

    PubMed Central

    Vaeth, Martin; Gogishvili, Tea; Bopp, Tobias; Klein, Matthias; Berberich-Siebelt, Friederike; Gattenloehner, Stefan; Avots, Andris; Sparwasser, Tim; Grebe, Nadine; Schmitt, Edgar; Hünig, Thomas; Serfling, Edgar; Bodor, Josef

    2011-01-01

    Inducible cAMP early repressor (ICER) is a transcriptional repressor, which, because of alternate promoter use, is generated from the 3′ region of the cAMP response modulator (Crem) gene. Its expression and nuclear occurrence are elevated by high cAMP levels in naturally occurring regulatory T cells (nTregs). Using two mouse models, we demonstrate that nTregs control the cellular localization of ICER/CREM, and thereby inhibit IL-2 synthesis in conventional CD4+ T cells. Ablation of nTregs in depletion of regulatory T-cell (DEREG) mice resulted in cytosolic localization of ICER/CREM and increased IL-2 synthesis upon stimulation. Direct contacts between nTregs and conventional CD4+ T cells led to nuclear accumulation of ICER/CREM and suppression of IL-2 synthesis on administration of CD28 superagonistic (CD28SA) Ab. In a similar way, nTregs communicated with B cells and induced the cAMP-driven nuclear localization of ICER/CREM. High levels of ICER suppressed the induction of nuclear factor of activated T cell c1 (Nfatc1) gene in T cells whose inducible Nfatc1 P1 promoter bears two highly conserved cAMP-responsive elements to which ICER/CREM can bind. These findings suggest that nTregs suppress T-cell responses by the cAMP-dependent nuclear accumulation of ICER/CREM and inhibition of NFATc1 and IL-2 induction. PMID:21262800

  7. OX40 ligand-transduced tumor cell vaccine synergizes with GM-CSF and requires CD40-Apc signaling to boost the host T cell antitumor response.

    PubMed

    Gri, Giorgia; Gallo, Elena; Di Carlo, Emma; Musiani, Piero; Colombo, Mario P

    2003-01-01

    Efficient T cell priming by GM-CSF and CD40 ligand double-transduced C26 murine colon carcinoma is not sufficient to cure metastases in a therapeutic setting. To determine whether a cellular vaccine that interacts directly with both APC and T cells in vivo might be superior, we generated C26 carcinoma cells transduced with the T cell costimulatory molecule OX40 ligand (OX40L) either alone (C26/OX40L) or together with GM-CSF (C26/GM/OX40L), which is known to activate APC. Mice injected with C26/OX40L cells displayed only a delay in tumor growth, while the C26/GM/OX40L tumor regressed in 85% of mice. Tumor rejection required granulocytes, CD4+, CD8+ T cells, and APC-mediated CD40-CD40 ligand cosignaling, but not IFN-gamma or IL-12 as shown using subset-depleted and knockout (KO) mice. CD40KO mice primed with C26/GM/OX40L cells failed to mount a CTL response, and T cells infiltrating the C26/GM/OX40L tumor were OX40 negative, suggesting an impairment in APC-T cell cross-talk in CD40KO mice. Indeed, CD4+ T cell-depleted mice failed to mount any CTL activity against the C26 tumor, while treatment with agonistic mAb to CD40, which acts on APC, bypassed the requirement for CD4+ T cells and restored CTL activation. C26/GM/OX40L cells cured 83% of mice bearing lung metastases, whereas C26/OX40L or C26/GM vaccination cured only 28 and 16% of mice, respectively. These results indicate the synergistic activity of OX40L and GM-CSF in a therapeutic setting.

  8. Automated red blood cell depletion in ABO incompatible grafts in the pediatric setting.

    PubMed

    Del Fante, Claudia; Scudeller, Luigia; Recupero, Santina; Viarengo, Gianluca; Boghen, Stella; Gurrado, Antonella; Zecca, Marco; Seghatchian, Jerard; Perotti, Cesare

    2017-12-01

    Bone marrow ABO incompatible transplantations require graft manipulation prior to infusion to avoid potentially lethal side effects. We analyzed the influence of pre-manipulation factors (temperature at arrival, transit time, time of storage at 4°C until processing and total time from collection to red blood cell depletion) on the graft quality of 21 red blood cell depletion procedures in ABO incompatible pediatric transplants. Bone marrow collections were processed using the Spectra Optia ® (Terumo BCT) automated device. Temperature at arrival ranged between 4°C and 6°C, median transit time was 9.75h (range 0.33-28), median time of storage at 4°-6°C until processing was 1.8h (range 0.41-18.41) and median time from collection to RBC depletion was 21h (range1-39.4). Median percentage of red blood cell depletion was 97.7 (range 95.4-98.5), median mononuclear cells recovery was 92.2% (range 40-121.2), median CD34+ cell recovery was 93% (range 69.9-161.2), median cell viability was 97.7% (range 94-99.3) and median volume reduction was 83.9% (range 82-92). Graft quality was not significantly different between BM units median age. Our preliminary data show that when all good manifacturing practices are respected the post-manipulation graft quality is excellent also for those units processed after 24h. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. CD4+ T-cell responses to foot-and-mouth disease virus in vaccinated cattle.

    PubMed

    Carr, B Veronica; Lefevre, Eric A; Windsor, Miriam A; Inghese, Cristina; Gubbins, Simon; Prentice, Helen; Juleff, Nicholas D; Charleston, Bryan

    2013-01-01

    We have performed a series of studies to investigate the role of CD4(+) T-cells in the immune response to foot-and-mouth disease virus (FMDV) post-vaccination. Virus neutralizing antibody titres (VNT) in cattle vaccinated with killed FMD commercial vaccine were significantly reduced and class switching delayed as a consequence of rigorous in vivo CD4(+) T-cell depletion. Further studies were performed to examine whether the magnitude of T-cell proliferative responses correlated with the antibody responses. FMD vaccination was found to induce T-cell proliferative responses, with CD4(+) T-cells responding specifically to the FMDV antigen. In addition, gamma interferon (IFN-γ) was detected in the supernatant of FMDV antigen-stimulated PBMC and purified CD4(+) T-cells from vaccinated cattle. Similarly, intracellular IFN-γ could be detected specifically in purified CD4(+) T-cells after restimulation. It was not possible to correlate in vitro proliferative responses or IFN-γ production of PBMC with VNT, probably as a consequence of the induction of T-independent and T-dependent antibody responses and antigen non-specific T-cell responses. However, our studies demonstrate the importance of stimulating CD4(+) T-cell responses for the induction of optimum antibody responses to FMD-killed vaccines.

  10. A doxycycline-dependent human immunodeficiency virus type 1 replicates in vivo without inducing CD4+ T-cell depletion

    PubMed Central

    Legrand, Nicolas; van der Velden, Gisela J.; Fang, Raphaël Ho Tsong; Douaisi, Marc; Weijer, Kees; Das, Atze T.; Blom, Bianca; Uittenbogaart, Christel H.; Berkhout, Ben

    2012-01-01

    A novel genetic approach for the control of virus replication was used for the design of a conditionally replicating human immunodeficiency virus (HIV) variant, HIV-rtTA. HIV-rtTA gene expression and virus replication are strictly dependent on the presence of a non-toxic effector molecule, doxycycline (dox), and thus can be turned on and off at will in a graded and reversible manner. The in vivo replication capacity, pathogenicity and genetic stability of this HIV-rtTA variant were evaluated in a humanized mouse model of haematopoiesis that harbours lymphoid and myeloid components of the human immune system (HIS). Infection of dox-fed BALB Rag/γc HIS (BRG-HIS) mice with HIV-rtTA led to the establishment of a productive infection without CD4+ T-cell depletion. The virus did not show any sign of escape from dox control for up to 10 weeks after the onset of infection. No reversion towards a functional Tat–transactivating responsive (TAR) RNA element axis was observed, confirming the genetic stability of the HIV-rtTA variant in vivo. These results demonstrate the proof of concept that HIV-rtTA replicates efficiently in vivo. HIV-rtTA is a promising tool for fundamental research to study virus–host interactions in vivo in a controlled fashion. PMID:22647372

  11. Specific Depletion of Ly6Chi Inflammatory Monocytes Prevents Immunopathology in Experimental Cerebral Malaria

    PubMed Central

    Kuepper, Janina M.; Biswas, Aindrila; Djie-Maletz, Andrea; Limmer, Andreas; van Rooijen, Nico; Mack, Matthias; Hoerauf, Achim; Dunay, Ildiko Rita

    2015-01-01

    Plasmodium berghei ANKA (PbA) infection of C57BL/6 mice leads to experimental cerebral malaria (ECM) that is commonly associated with serious T cell mediated damage. In other parasitic infection models, inflammatory monocytes have been shown to regulate Th1 responses but their role in ECM remains poorly defined, whereas neutrophils are reported to contribute to ECM immune pathology. Making use of the recent development of specific monoclonal antibodies (mAb), we depleted in vivo Ly6Chi inflammatory monocytes (by anti-CCR2), Ly6G+ neutrophils (by anti-Ly6G) or both cell types (by anti-Gr1) during infection with Ovalbumin-transgenic PbA parasites (PbTg). Notably, the application of anti-Gr1 or anti-CCR2 but not anti-Ly6G antibodies into PbTg-infected mice prevented ECM development. In addition, depletion of Ly6Chi inflammatory monocytes but not neutrophils led to decreased IFNγ levels and IFNγ+CD8+ T effector cells in the brain. Importantly, anti-CCR2 mAb injection did not prevent the generation of PbTg-specific T cell responses in the periphery, whereas anti-Gr1 mAb injection strongly diminished T cell frequencies and CTL responses. In conclusion, the specific depletion of Ly6Chi inflammatory monocytes attenuated brain inflammation and immune cell recruitment to the CNS, which prevented ECM following Plasmodium infection, pointing out a substantial role of Ly6C+ monocytes in ECM inflammatory processes. PMID:25884830

  12. A phase I-II trial to examine the toxicity of CMV- and EBV-specific cytotoxic T lymphocytes when used for prophylaxis against EBV and CMV disease in recipients of CD34-selected/T cell-depleted stem cell transplants.

    PubMed

    Lucas, K G; Sun, Q; Burton, R L; Tilden, A; Vaughan, W P; Carabasi, M; Salzman, D; Ship, A

    2000-07-01

    complications in recipients of CD34 selected/T-cell depleted stem cell transplants (SCT). EBV/CMV-specific CTL will be generated from peripheral blood mononuclear cells (PBMC) of EBV/CMV-seropositive donors in a course of from 21-28 days by weekly stimulation with autologous BLCLpp65. Qualified CTL will be administered to consenting patients at 40, 60, and 80 days post-transpOFF criteria of molecular virology and immunological reconstitution, which include blood levels of pp65 antigen and EBV viral DNA, and virus-specific CTL precursor frequency. Patients will also be tested for replication-competent retrovirus at 3, 6, and 12 month intervals post-transplant to ensure bio-safety.

  13. T cell-replacing factor for glucocorticosteroid-induced immunoglobulin production. A unique steroid-dependent cytokine

    PubMed Central

    1983-01-01

    Glucocorticosteroids (GCS) added to otherwise unstimulated cultures of human peripheral blood mononuclear cells (PBMC) induce the synthesis and secretion of all classes of immunoglobulin. The magnitude of this response is similar to that seen with other polyclonal B cell activators such as pokeweed mitogen (PWM), and like that of PWM, the steroid effect is dependent on both T cells and monocytes. To determine the cellular target for GCS in these cultures, separated populations of T cells and non-T cells were preincubated with steroids and then recombined. No immunoglobulin was produced in any of these preincubation experiments. As a different approach to this question, supernatants were collected from various cell populations following stimulation with PWM, concanavalin A (Con A), phytohemagglutinin (PHA), alloantigens, or GCS. These supernatants were tested for their effects on GCS-induced Ig production by B cells. Supernatants from 3-d cultures of unstimulated, as well as GCS-treated, PBMC contained a T cell- replacing factor that permitted T-depleted PBMC to produce Ig upon steroid stimulation. This supernatant factor (TRF-S) could be produced in the absence of steroid stimulation, but both the factor and GCS were necessary for the induction of Ig synthesis. Production of the TRF-S required the presence of both T cells and adherent cells in culture and was found in the highest concentrations at 3-4 d of culture. Supernatants from cultures stimulated with PWM, PHA, Con A, and alloantigens did not contain detectable TRF-S activity, and TRF-S was unable to replace helper T cells for PWM-induced Ig production. TRF-S required the presence of adherent cells in the T cell-depleted responder population for its action. Further, it was effective in inducing Ig production along with GCS in the presence of a sufficient concentration of cyclosporin A to block all T cell helper activity for primary responses of PBMC to PWM or GCS. TRF-S was inactivated by trypsin treatment

  14. Requirement for CD4 T Cell Help in Generating Functional CD8 T Cell Memory

    NASA Astrophysics Data System (ADS)

    Shedlock, Devon J.; Shen, Hao

    2003-04-01

    Although primary CD8 responses to acute infections are independent of CD4 help, it is unknown whether a similar situation applies to secondary responses. We show that depletion of CD4 cells during the recall response has minimal effect, whereas depletion during the priming phase leads to reduced responses by memory CD8 cells to reinfection. Memory CD8 cells generated in CD4+/+ mice responded normally when transferred into CD4-/- hosts, whereas memory CD8 cells generated in CD4-/- mice mounted defective recall responses in CD4+/+ adoptive hosts. These results demonstrate a previously undescribed role for CD4 help in the development of functional CD8 memory.

  15. T cells establish and maintain CNS viral infection in HIV-infected humanized mice.

    PubMed

    Honeycutt, Jenna B; Liao, Baolin; Nixon, Christopher C; Cleary, Rachel A; Thayer, William O; Birath, Shayla L; Swanson, Michael D; Sheridan, Patricia; Zakharova, Oksana; Prince, Francesca; Kuruc, JoAnn; Gay, Cynthia L; Evans, Chris; Eron, Joseph J; Wahl, Angela; Garcia, J Victor

    2018-06-04

    The human brain is an important site of HIV replication and persistence during antiretroviral therapy (ART). Direct evaluation of HIV infection in the brains of otherwise healthy individuals is not feasible; therefore, we performed a large-scale study of bone marrow/liver/thymus (BLT) humanized mice as an in vivo model to study HIV infection in the brain. Human immune cells, including CD4+ T cells and macrophages, were present throughout the BLT mouse brain. HIV DNA, HIV RNA, and/or p24+ cells were observed in the brains of HIV-infected animals, regardless of the HIV isolate used. HIV infection resulted in decreased numbers of CD4+ T cells, increased numbers of CD8+ T cells, and a decreased CD4+/CD8+ T cell ratio in the brain. Using humanized T cell-only mice (ToM), we demonstrated that T cells establish and maintain HIV infection of the brain in the complete absence of human myeloid cells. HIV infection of ToM resulted in CD4+ T cell depletion and a reduced CD4+/CD8+ T cell ratio. ART significantly reduced HIV levels in the BLT mouse brain, and the immune cell populations present were indistinguishable from those of uninfected controls, which demonstrated the effectiveness of ART in controlling HIV replication in the CNS and returning cellular homeostasis to a pre-HIV state.

  16. CD8+ T cells complement antibodies in protecting against yellow fever virus.

    PubMed

    Bassi, Maria R; Kongsgaard, Michael; Steffensen, Maria A; Fenger, Christina; Rasmussen, Michael; Skjødt, Karsten; Finsen, Bente; Stryhn, Anette; Buus, Søren; Christensen, Jan P; Thomsen, Allan R

    2015-02-01

    The attenuated yellow fever (YF) vaccine (YF-17D) was developed in the 1930s, yet little is known about the protective mechanisms underlying its efficiency. In this study, we analyzed the relative contribution of cell-mediated and humoral immunity to the vaccine-induced protection in a murine model of YF-17D infection. Using different strains of knockout mice, we found that CD4(+) T cells, B cells, and Abs are required for full clinical protection of vaccinated mice, whereas CD8(+) T cells are dispensable for long-term survival after intracerebral challenge. However, by analyzing the immune response inside the infected CNS, we observed an accelerated T cell influx into the brain after intracerebral challenge of vaccinated mice, and this T cell recruitment correlated with improved virus control in the brain. Using mice deficient in B cells we found that, in the absence of Abs, YF vaccination can still induce some antiviral protection, and in vivo depletion of CD8(+) T cells from these animals revealed a pivotal role for CD8(+) T cells in controlling virus replication in the absence of a humoral response. Finally, we demonstrated that effector CD8(+) T cells also contribute to viral control in the presence of circulating YF-specific Abs. To our knowledge, this is the first time that YF-specific CD8(+) T cells have been demonstrated to possess antiviral activity in vivo. Copyright © 2015 by The American Association of Immunologists, Inc.

  17. Regulatory T cells in cattle and their potential role in bovine paratuberculosis.

    PubMed

    Coussens, Paul M; Sipkovsky, Sue; Murphy, Brooke; Roussey, Jon; Colvin, Christopher J

    2012-05-01

    The intracellular bacterium Mycobacterium avium subspecies paratuberculosis (MAP) causes Johne's disease in wild and domestic ruminants. Johne's disease presents as a chronic enteritis with severe inflammation of intestinal tissues, characterized by widespread infiltration of macrophages, the target cell of MAP. Clinical signs of Johne's disease are typically accompanied by a loss of peripheral CD4+ T cell responses to MAP antigens and an increase in anti-MAP serum IgG levels. Recently, it was proposed that regulatory T cells might develop over the lengthy course of subclinical MAP infection. In the past five years, significant progress in defining bovine regulatory T cells has been made. These studies grew out of observations that IL-10 is produced by PBMCs in response to MAP antigen stimulation and that neutralization of this IL-10 could enhance IFN-γ production from MAP-antigen reactive effector T cells. Depletion studies revealed that MAP responsive cell populations producing IL-10 were largely CD4+ and CD25+, although monocytes have also been shown to produce IL-10 in response to MAP. In addition, evidence for a regulatory population of γδ T cells has also begun to accumulate. We summarize current thinking regarding regulatory T cells in MAP infection and provide data suggesting a potential link between regulatory T cells, bovine leukemia virus, and MAP. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Donor-derived CD19-targeted T cells cause regression of malignancy persisting after allogeneic hematopoietic stem cell transplantation.

    PubMed

    Kochenderfer, James N; Dudley, Mark E; Carpenter, Robert O; Kassim, Sadik H; Rose, Jeremy J; Telford, William G; Hakim, Frances T; Halverson, David C; Fowler, Daniel H; Hardy, Nancy M; Mato, Anthony R; Hickstein, Dennis D; Gea-Banacloche, Juan C; Pavletic, Steven Z; Sportes, Claude; Maric, Irina; Feldman, Steven A; Hansen, Brenna G; Wilder, Jennifer S; Blacklock-Schuver, Bazetta; Jena, Bipulendu; Bishop, Michael R; Gress, Ronald E; Rosenberg, Steven A

    2013-12-12

    New treatments are needed for B-cell malignancies persisting after allogeneic hematopoietic stem cell transplantation (alloHSCT). We conducted a clinical trial of allogeneic T cells genetically modified to express a chimeric antigen receptor (CAR) targeting the B-cell antigen CD19. T cells for genetic modification were obtained from each patient's alloHSCT donor. All patients had malignancy that persisted after alloHSCT and standard donor lymphocyte infusions (DLIs). Patients did not receive chemotherapy prior to the CAR T-cell infusions and were not lymphocyte depleted at the time of the infusions. The 10 treated patients received a single infusion of allogeneic anti-CD19-CAR T cells. Three patients had regressions of their malignancies. One patient with chronic lymphocytic leukemia (CLL) obtained an ongoing complete remission after treatment with allogeneic anti-CD19-CAR T cells, another CLL patient had tumor lysis syndrome as his leukemia dramatically regressed, and a patient with mantle cell lymphoma obtained an ongoing partial remission. None of the 10 patients developed graft-versus-host disease (GVHD). Toxicities included transient hypotension and fever. We detected cells containing the anti-CD19-CAR gene in the blood of 8 of 10 patients. These results show for the first time that donor-derived allogeneic anti-CD19-CAR T cells can cause regression of B-cell malignancies resistant to standard DLIs without causing GVHD.

  19. Interleukin 2 and interleukin 10 function synergistically to promote CD8+ T cell cytotoxicity, which is suppressed by regulatory T cells in breast cancer.

    PubMed

    Li, Xiaogang; Lu, Ping; Li, Bo; Zhang, Wanfu; Yang, Rong; Chu, Yan; Luo, Kaiyuan

    2017-06-01

    The precise role of interleukin (IL)-10 in breast cancer is not clear. Previous studies suggested a tumor-promoting role of IL-10 in breast cancer, whereas recent discoveries that IL-10 activated and expanded tumor-resident CD8 + T cells challenged the traditional view. Here, we investigated the role of IL-10 in HLA-A2-positive breast cancer patients with Grade III, Stage IIA or IIB in-situ and invasive ductal carcinoma, and compared it with that of IL-2, the canonical CD8 + T cell growth factor. We first observed that breast cancer patients presented higher serum levels of IL-2 and IL-10 than healthy controls. Upon prolonged TCR stimulation, peripheral blood CD8 + T cells from breast cancer patients tended to undergo apoptosis, which could be prevented by the addition of IL-2 and/or IL-10. The cytotoxicity of TCR-activated CD8 + T cells was also enhanced by exogenous IL-2 and/or IL-10. Interestingly, IL-2 and IL-10 demonstrated synergistic effects, since the enhancement in CD8 + T cell function when both cytokines were added was greater than the sum of the improvements mediated by each individual cytokine. IL-10 by itself could not promote the proliferation of CD8 + T cells but could significantly enhance IL-2-mediated promotion of CD8 + T cell proliferation. In addition, the cytotoxicity of tumor-infiltrating CD8 + T cells in breast tumor was elevated when both IL-2 and IL-10 were present but not when either one was absent. This synergistic effect was stopped by CD4 + CD25 + regulatory T cells (Treg), which depleted IL-2 in a cell number-dependent manner. Together, these results demonstrated that IL-2 and IL-10 could work synergistically to improve the survival, proliferation, and cytotoxicity of activated CD8 + T cells, an effect suppressible by CD4 + CD25 + Treg cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Role of T cell death in maintaining immune tolerance during persistent viral hepatitis.

    PubMed

    Larrubia, Juan Ramón; Lokhande, Megha Uttam; García-Garzón, Silvia; Miquel, Joaquín; Subirá, Dolores; Sanz-de-Villalobos, Eduardo

    2013-03-28

    Virus-specific T cells play an important role in the resolution of hepatic infection. However, during chronic hepatitis infection these cells lack their effector functions and fail to control the virus. Hepatitis B virus and hepatitis C virus have developed several mechanisms to generate immune tolerance. One of these strategies is the depletion of virus-specific T cells by apoptosis. The immunotolerogenic liver has unique property to retain and activate naïve T cell to avoid the over reactivation of immune response against antigens which is exploited by hepatotropic viruses to persist. The deletion of the virus-specific T cells occurs by intrinsic (passive) apoptotic mechanism. The pro-apoptotic molecule Bcl-2 interacting mediator (Bim) has attracted increasing attention as a pivotal involvement in apoptosis, as a regulator of tissue homeostasis and an enhancer for the viral persistence. Here, we reviewed our current knowledge on the evidence showing critical role of Bim in viral-specific T cell death by apoptotic pathways and helps in the immune tolerance.

  1. MHCII-mediated dialog between group 2 innate lymphoid cells and CD4(+) T cells potentiates type 2 immunity and promotes parasitic helminth expulsion.

    PubMed

    Oliphant, Christopher J; Hwang, You Yi; Walker, Jennifer A; Salimi, Maryam; Wong, See Heng; Brewer, James M; Englezakis, Alexandros; Barlow, Jillian L; Hams, Emily; Scanlon, Seth T; Ogg, Graham S; Fallon, Padraic G; McKenzie, Andrew N J

    2014-08-21

    Group 2 innate lymphoid cells (ILC2s) release interleukin-13 (IL-13) during protective immunity to helminth infection and detrimentally during allergy and asthma. Using two mouse models to deplete ILC2s in vivo, we demonstrate that T helper 2 (Th2) cell responses are impaired in the absence of ILC2s. We show that MHCII-expressing ILC2s interact with antigen-specific T cells to instigate a dialog in which IL-2 production from T cells promotes ILC2 proliferation and IL-13 production. Deletion of MHCII renders IL-13-expressing ILC2s incapable of efficiently inducing Nippostrongylus brasiliensis expulsion. Thus, during transition to adaptive T cell-mediated immunity, the ILC2 and T cell crosstalk contributes to their mutual maintenance, expansion and cytokine production. This interaction appears to augment dendritic-cell-induced T cell activation and identifies a previously unappreciated pathway in the regulation of type-2 immunity. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  2. CD8+ memory T-cell inflation renders compromised CD4+ T-cell-dependent CD8+ T-cell immunity via naïve T-cell anergy.

    PubMed

    Xu, Aizhang; Freywald, Andrew; Xie, Yufeng; Li, Zejun; Xiang, Jim

    2017-01-01

    Whether inflation of CD8 + memory T (mT) cells, which is often derived from repeated prime-boost vaccinations or chronic viral infections in the elderly, would affect late CD8 + T-cell immunity is a long-standing paradox. We have previously established an animal model with mT-cell inflation by transferring ConA-stimulated monoclonal CD8 + T cells derived from Ova-specific T-cell-receptor transgenic OTI mice into irradiation-induced lymphopenic B6 mice. In this study, we also established another two animal models with mT-cell inflation by transferring, 1) ConA-stimulated monoclonal CD8 + T cells derived from lymphocytic choriomeningitis virus glycoprotein-specific T-cell-receptor transgenic P14 mice, and 2) ConA-stimulated polyclonal CD8 + T cells derived from B6.1 mice into B6 mice with irradiation-induced lymphopenia. We vaccinated these mice with recombinant Ova-expressing Listeria monocytogenes and Ova-pulsed dendritic cells, which stimulated CD4 + T cell-independent and CD4 + T-cell-dependent CD8 + T-cell responses, respectively, and assessed Ova-specific CD8 + T-cell responses by flow cytometry. We found that Ova-specific CD8 + T-cell responses derived from the latter but not the former vaccination were significantly reduced in mice with CD8 + mT-cell inflation compared to wild-type B6 mice. We determined that naïve CD8 + T cells purified from splenocytes of mice with mT-cell inflation had defects in cell proliferation upon stimulation in vitro and in vivo and upregulated T-cell anergy-associated Itch and GRAIL molecules. Taken together, our data reveal that CD8 + mT-cell inflation renders compromised CD4 + T-cell-dependent CD8 + T-cell immunity via naïve T-cell anergy, and thus show promise for the design of efficient vaccines for elderly patients with CD8 + mT-cell inflation.

  3. Cholesterol depletion by methyl-β-cyclodextrin enhances cell proliferation and increases the number of desmin-positive cells in myoblast cultures.

    PubMed

    Portilho, Débora M; Soares, Carolina P; Morrot, Alexandre; Thiago, Leandro S; Butler-Browne, Gillian; Savino, Wilson; Costa, Manoel L; Mermelstein, Cláudia

    2012-11-05

    Skeletal myogenesis comprises myoblast replication and differentiation into striated multinucleated myotubes. Agents that interfere with myoblast replication are important tools for the understanding of myogenesis. Recently, we showed that cholesterol depletion by methyl-β-cyclodextrin (MCD) enhances the differentiation step in chick-cultured myogenic cells, involving the activation of the Wnt/β-catenin signaling pathway. However, the effects of cholesterol depletion on myoblast replication have not been carefully studied. Here we show that MCD treatment increases cell proliferation in primary chick myogenic cell cultures. Treatment of myogenic cells with the anti-mitotic reagent cytosine arabinoside, immediately following cholesterol depletion, blocks the MCD-induced effects on proliferation. Cholesterol depletion induced an increase in the number of desmin-positive mononucleated cells, and an increase in desmin expression. MCD induces an increase in the expression of the cell cycle regulator p53 and the master switch gene MyoD1. Treatment with BIO, a specific inhibitor of GSK3β, induced effects similar to MCD on cell proliferation; while treatment with Dkk1, a specific inhibitor of the Wnt/β-catenin pathway, neutralized the effects of MCD. These findings indicate that rapid changes in the cholesterol content in cell membranes of myoblasts can induce cell proliferation, possibly by the activation of the Wnt/β-catenin signaling pathway. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Age-Related Mitochondrial DNA Depletion and the Impact on Pancreatic Beta Cell Function

    PubMed Central

    Nile, Donna L.; Brown, Audrey E.; Kumaheri, Meutia A.; Blair, Helen R.; Heggie, Alison; Miwa, Satomi; Cree, Lynsey M.; Payne, Brendan; Chinnery, Patrick F.; Brown, Louise; Gunn, David A.; Walker, Mark

    2014-01-01

    Type 2 diabetes is characterised by an age-related decline in insulin secretion. We previously identified a 50% age-related decline in mitochondrial DNA (mtDNA) copy number in isolated human islets. The purpose of this study was to mimic this degree of mtDNA depletion in MIN6 cells to determine whether there is a direct impact on insulin secretion. Transcriptional silencing of mitochondrial transcription factor A, TFAM, decreased mtDNA levels by 40% in MIN6 cells. This level of mtDNA depletion significantly decreased mtDNA gene transcription and translation, resulting in reduced mitochondrial respiratory capacity and ATP production. Glucose-stimulated insulin secretion was impaired following partial mtDNA depletion, but was normalised following treatment with glibenclamide. This confirms that the deficit in the insulin secretory pathway precedes K+ channel closure, indicating that the impact of mtDNA depletion is at the level of mitochondrial respiration. In conclusion, partial mtDNA depletion to a degree comparable to that seen in aged human islets impaired mitochondrial function and directly decreased insulin secretion. Using our model of partial mtDNA depletion following targeted gene silencing of TFAM, we have managed to mimic the degree of mtDNA depletion observed in aged human islets, and have shown how this correlates with impaired insulin secretion. We therefore predict that the age-related mtDNA depletion in human islets is not simply a biomarker of the aging process, but will contribute to the age-related risk of type 2 diabetes. PMID:25532126

  5. Age-related mitochondrial DNA depletion and the impact on pancreatic Beta cell function.

    PubMed

    Nile, Donna L; Brown, Audrey E; Kumaheri, Meutia A; Blair, Helen R; Heggie, Alison; Miwa, Satomi; Cree, Lynsey M; Payne, Brendan; Chinnery, Patrick F; Brown, Louise; Gunn, David A; Walker, Mark

    2014-01-01

    Type 2 diabetes is characterised by an age-related decline in insulin secretion. We previously identified a 50% age-related decline in mitochondrial DNA (mtDNA) copy number in isolated human islets. The purpose of this study was to mimic this degree of mtDNA depletion in MIN6 cells to determine whether there is a direct impact on insulin secretion. Transcriptional silencing of mitochondrial transcription factor A, TFAM, decreased mtDNA levels by 40% in MIN6 cells. This level of mtDNA depletion significantly decreased mtDNA gene transcription and translation, resulting in reduced mitochondrial respiratory capacity and ATP production. Glucose-stimulated insulin secretion was impaired following partial mtDNA depletion, but was normalised following treatment with glibenclamide. This confirms that the deficit in the insulin secretory pathway precedes K+ channel closure, indicating that the impact of mtDNA depletion is at the level of mitochondrial respiration. In conclusion, partial mtDNA depletion to a degree comparable to that seen in aged human islets impaired mitochondrial function and directly decreased insulin secretion. Using our model of partial mtDNA depletion following targeted gene silencing of TFAM, we have managed to mimic the degree of mtDNA depletion observed in aged human islets, and have shown how this correlates with impaired insulin secretion. We therefore predict that the age-related mtDNA depletion in human islets is not simply a biomarker of the aging process, but will contribute to the age-related risk of type 2 diabetes.

  6. Histone h1 depletion impairs embryonic stem cell differentiation.

    PubMed

    Zhang, Yunzhe; Cooke, Marissa; Panjwani, Shiraj; Cao, Kaixiang; Krauth, Beth; Ho, Po-Yi; Medrzycki, Magdalena; Berhe, Dawit T; Pan, Chenyi; McDevitt, Todd C; Fan, Yuhong

    2012-01-01

    Pluripotent embryonic stem cells (ESCs) are known to possess a relatively open chromatin structure; yet, despite efforts to characterize the chromatin signatures of ESCs, the role of chromatin compaction in stem cell fate and function remains elusive. Linker histone H1 is important for higher-order chromatin folding and is essential for mammalian embryogenesis. To investigate the role of H1 and chromatin compaction in stem cell pluripotency and differentiation, we examine the differentiation of embryonic stem cells that are depleted of multiple H1 subtypes. H1c/H1d/H1e triple null ESCs are more resistant to spontaneous differentiation in adherent monolayer culture upon removal of leukemia inhibitory factor. Similarly, the majority of the triple-H1 null embryoid bodies (EBs) lack morphological structures representing the three germ layers and retain gene expression signatures characteristic of undifferentiated ESCs. Furthermore, upon neural differentiation of EBs, triple-H1 null cell cultures are deficient in neurite outgrowth and lack efficient activation of neural markers. Finally, we discover that triple-H1 null embryos and EBs fail to fully repress the expression of the pluripotency genes in comparison with wild-type controls and that H1 depletion impairs DNA methylation and changes of histone marks at promoter regions necessary for efficiently silencing pluripotency gene Oct4 during stem cell differentiation and embryogenesis. In summary, we demonstrate that H1 plays a critical role in pluripotent stem cell differentiation, and our results suggest that H1 and chromatin compaction may mediate pluripotent stem cell differentiation through epigenetic repression of the pluripotency genes.

  7. Dimethyl fumarate–induced lymphopenia in MS due to differential T-cell subset apoptosis

    PubMed Central

    Ghadiri, Mahtab; Rezk, Ayman; Li, Rui; Evans, Ashley; Luessi, Felix; Zipp, Frauke; Giacomini, Paul S.; Antel, Jack

    2017-01-01

    Objective: To examine the mechanism underlying the preferential CD8+ vs CD4+ T-cell lymphopenia induced by dimethyl fumarate (DMF) treatment of MS. Methods: Total lymphocyte counts and comprehensive T-cell subset analyses were performed in high-quality samples obtained from patients with MS prior to and serially following DMF treatment initiation. Random coefficient mixed-effects analysis was used to model the trajectory of T-cell subset losses in vivo. Survival and apoptosis of distinct T-cell subsets were assessed following in vitro exposure to DMF. Results: Best-fit modeling indicated that the DMF-induced preferential reductions in CD8+ vs CD4+ T-cell counts nonetheless followed similar depletion kinetics, suggesting a similar rather than distinct mechanism involved in losses of both the CD8+ and CD4+ T cells. In vitro, DMF exposure resulted in dose-dependent reductions in T-cell survival, which were found to reflect apoptotic cell death. This DMF-induced apoptosis was greater for CD8+ vs CD4+, as well as for memory vs naive, and conventional vs regulatory T-cell subsets, a pattern which mirrored preferential T-cell subset losses that we observed during in vivo treatment of patients. Conclusions: Differential apoptosis mediated by DMF may underlie the preferential lymphopenia of distinct T-cell subsets, including CD8+ and memory T-cell subsets, seen in treated patients with MS. This differential susceptibility of distinct T-cell subsets to DMF-induced apoptosis may contribute to both the safety and efficacy profiles of DMF in patients with MS. PMID:28377940

  8. Specific depletion reveals a novel role for neutrophil-mediated protection in the liver during Listeria monocytogenes infection

    PubMed Central

    Carr, Karen D.; Sieve, Amy N.; Indramohan, Mohanalaxmi; Break, Timothy J.; Lee, Suhueng; Berg, Rance E.

    2012-01-01

    Summary Previous studies have suggested that neutrophils are required for resistance during infection with multiple pathogenic microorganisms. However, the depleting antibody used in those studies binds to both Ly6G and Ly6C (anti-Gr-1; clone RB6-8C5). This antibody has been shown to not only deplete neutrophils, but also monocytes, and a subset of CD8 T cells. Recently, an antibody against Ly6G has been characterized which specifically depletes neutrophils. In the present study, neutrophils are depleted using the antibody against Ly6G during infection with the intracellular bacterium, Listeria monocytogenes (LM). Our data show that neutrophil depleted mice are much less susceptible to infection than mice depleted with anti-Gr-1. Although neutrophils are required for clearance of LM, their importance is more pronounced in the liver and during a high-dose bacterial challenge. Furthermore, we demonstrate that protection mediated by neutrophils is due to production of TNF-α, but not IFN-γ. Additionally, neutrophils are not required for the recruitment of monocytes or the generation of adaptive T cell responses during LM infection. These studies highlight the importance of neutrophils during LM infection, and also indicate that depletion of neutrophils is less detrimental to the host than depletion of all Gr-1 expressing cell populations. PMID:21660934

  9. Regulation of Human γδ T Cells by BTN3A1 Protein Stability and ATP-Binding Cassette Transporters

    PubMed Central

    Rhodes, David A.; Chen, Hung-Chang; Williamson, James C.; Hill, Alfred; Yuan, Jack; Smith, Sam; Rhodes, Harriet; Trowsdale, John; Lehner, Paul J.; Herrmann, Thomas; Eberl, Matthias

    2018-01-01

    Activation of human Vγ9/Vδ2 T cells by “phosphoantigens” (pAg), the microbial metabolite (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP) and the endogenous isoprenoid intermediate isopentenyl pyrophosphate, requires expression of butyrophilin BTN3A molecules by presenting cells. However, the precise mechanism of activation of Vγ9/Vδ2 T cells by BTN3A molecules remains elusive. It is not clear what conformation of the three BTN3A isoforms transmits activation signals nor how externally delivered pAg accesses the cytosolic B30.2 domain of BTN3A1. To approach these problems, we studied two HLA haplo-identical HeLa cell lines, termed HeLa-L and HeLa-M, which showed marked differences in pAg-dependent stimulation of Vγ9/Vδ2 T cells. Levels of IFN-γ secretion by Vγ9/Vδ2 T cells were profoundly increased by pAg loading, or by binding of the pan-BTN3A specific agonist antibody CD277 20.1, in HeLa-M compared to HeLa-L cells. IL-2 production from a murine hybridoma T cell line expressing human Vγ9/Vδ2 T cell receptor (TCR) transgenes confirmed that the differential responsiveness to HeLa-L and HeLa-M was TCR dependent. By tissue typing, both HeLa lines were shown to be genetically identical and full-length transcripts of the three BTN3A isoforms were detected in equal abundance with no sequence variation. Expression of BTN3A and interacting molecules, such as periplakin or RhoB, did not account for the functional variation between HeLa-L and HeLa-M cells. Instead, the data implicate a checkpoint controlling BTN3A1 stability and protein trafficking, acting at an early time point in its maturation. In addition, plasma membrane profiling was used to identify proteins upregulated in HMB-PP-treated HeLa-M. ABCG2, a member of the ATP-binding cassette (ABC) transporter family was the most significant candidate, which crucially showed reduced expression in HeLa-L. Expression of a subset of ABC transporters, including ABCA1 and ABCG1, correlated with

  10. Invariant natural killer T cells ameliorate murine chronic GVHD by expanding donor regulatory T cells.

    PubMed

    Du, Jing; Paz, Katelyn; Thangavelu, Govindarajan; Schneidawind, Dominik; Baker, Jeanette; Flynn, Ryan; Duramad, Omar; Feser, Colby; Panoskaltsis-Mortari, Angela; Negrin, Robert S; Blazar, Bruce R

    2017-06-08

    Chronic graft-versus-host-disease (cGVHD) can cause multiorgan system disease, typically with autoimmune-like features, resulting in high mortality and morbidity caused by treatment limitations. Invariant natural killer T cells (iNKTs), a small population characterized by expression of a semi-invariant T-cell receptor, rapidly produce copious amounts of diverse cytokines on activation that exert potent immune regulatory function. Here, we show that iNKTs are significantly reduced in a cGVHD murine model that recapitulates several aspects of autoimmunity and organ fibrosis observed in patients with cGVHD. Low iNKT infused doses effectively prevented and, importantly, reversed established cGVHD, as did third-party iNKTs. iNKTs suppressed the autoimmune response by reducing the germinal center (GC) reaction, which was associated with an increase in total Tregs and follicular Tregs (Tfr) that control the GC reaction, along with pathogenic antibody production. Treg depletion during iNKT infusions completely abolished iNKT efficacy in treating cGVHD. iNKT cell interleukin 4 production and GC migration were critical to cGVHD reversal. In vivo stimulation of iNKT cells by α-galactosyl-ceramide was effective in both preventing and treating cGVHD. Together, this study demonstrates iNKT deficiency in cGVHD mice and highlights the key role of iNKTs in regulating cGVHD pathogenesis and as a potentially novel prophylactic and therapeutic option for patients with cGVHD. © 2017 by The American Society of Hematology.

  11. Novel Mouse Xenograft Models Reveal a Critical Role of CD4+ T Cells in the Proliferation of EBV-Infected T and NK Cells

    PubMed Central

    Arai, Ayako; Nakazawa, Atsuko; Kawano, Fuyuko; Ichikawa, Sayumi; Shimizu, Norio; Yamamoto, Naoki; Morio, Tomohiro; Ohga, Shouichi; Nakamura, Hiroyuki; Ito, Mamoru; Miura, Osamu; Komano, Jun; Fujiwara, Shigeyoshi

    2011-01-01

    Epstein-Barr virus (EBV), a ubiquitous B-lymphotropic herpesvirus, ectopically infects T or NK cells to cause severe diseases of unknown pathogenesis, including chronic active EBV infection (CAEBV) and EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH). We developed xenograft models of CAEBV and EBV-HLH by transplanting patients' PBMC to immunodeficient mice of the NOD/Shi-scid/IL-2Rγnull strain. In these models, EBV-infected T, NK, or B cells proliferated systemically and reproduced histological characteristics of the two diseases. Analysis of the TCR repertoire expression revealed that identical predominant EBV-infected T-cell clones proliferated in patients and corresponding mice transplanted with their PBMC. Expression of the EBV nuclear antigen 1 (EBNA1), the latent membrane protein 1 (LMP1), and LMP2, but not EBNA2, in the engrafted cells is consistent with the latency II program of EBV gene expression known in CAEBV. High levels of human cytokines, including IL-8, IFN-γ, and RANTES, were detected in the peripheral blood of the model mice, mirroring hypercytokinemia characteristic to both CAEBV and EBV-HLH. Transplantation of individual immunophenotypic subsets isolated from patients' PBMC as well as that of various combinations of these subsets revealed a critical role of CD4+ T cells in the engraftment of EBV-infected T and NK cells. In accordance with this finding, in vivo depletion of CD4+ T cells by the administration of the OKT4 antibody following transplantation of PBMC prevented the engraftment of EBV-infected T and NK cells. This is the first report of animal models of CAEBV and EBV-HLH that are expected to be useful tools in the development of novel therapeutic strategies for the treatment of the diseases. PMID:22028658

  12. Novel mouse xenograft models reveal a critical role of CD4+ T cells in the proliferation of EBV-infected T and NK cells.

    PubMed

    Imadome, Ken-ichi; Yajima, Misako; Arai, Ayako; Nakazawa, Atsuko; Kawano, Fuyuko; Ichikawa, Sayumi; Shimizu, Norio; Yamamoto, Naoki; Morio, Tomohiro; Ohga, Shouichi; Nakamura, Hiroyuki; Ito, Mamoru; Miura, Osamu; Komano, Jun; Fujiwara, Shigeyoshi

    2011-10-01

    Epstein-Barr virus (EBV), a ubiquitous B-lymphotropic herpesvirus, ectopically infects T or NK cells to cause severe diseases of unknown pathogenesis, including chronic active EBV infection (CAEBV) and EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH). We developed xenograft models of CAEBV and EBV-HLH by transplanting patients' PBMC to immunodeficient mice of the NOD/Shi-scid/IL-2Rγ(null) strain. In these models, EBV-infected T, NK, or B cells proliferated systemically and reproduced histological characteristics of the two diseases. Analysis of the TCR repertoire expression revealed that identical predominant EBV-infected T-cell clones proliferated in patients and corresponding mice transplanted with their PBMC. Expression of the EBV nuclear antigen 1 (EBNA1), the latent membrane protein 1 (LMP1), and LMP2, but not EBNA2, in the engrafted cells is consistent with the latency II program of EBV gene expression known in CAEBV. High levels of human cytokines, including IL-8, IFN-γ, and RANTES, were detected in the peripheral blood of the model mice, mirroring hypercytokinemia characteristic to both CAEBV and EBV-HLH. Transplantation of individual immunophenotypic subsets isolated from patients' PBMC as well as that of various combinations of these subsets revealed a critical role of CD4+ T cells in the engraftment of EBV-infected T and NK cells. In accordance with this finding, in vivo depletion of CD4+ T cells by the administration of the OKT4 antibody following transplantation of PBMC prevented the engraftment of EBV-infected T and NK cells. This is the first report of animal models of CAEBV and EBV-HLH that are expected to be useful tools in the development of novel therapeutic strategies for the treatment of the diseases.

  13. [Hematopoietic Reconstitution and Prognosis of HLA Matched and Haploidentical Hematopoietic Stem Cell Transplantation Using Modified FC/ATG Conditioning for Treatment of Severe Aplastic Anemia].

    PubMed

    Wang, Li; Wu, Ya-Mei; Cao, Yong-Bin; Li, Xiao-Hong; Xu, Li-Xin; Wang, Hai-Tao; Gao, Ya-Hui; Wu, Xiao-Xiong

    2016-12-01

    To analyse the feasibility and compare differences between hematopoietic reconstitution and prognosis of patients with severe aplastic anemia(SAA) after matched sibling donor (MSD) or haploidentical family donor (HFD) hematopoietic stem cell transplantation (HSCT) using the modified FC/ATG conditioning. The clinical data of 56 patients with SAA who received HSCT in First Affiliated Hospital of Chinese PLA General Hospital from January 2011 to June 2016 were analyzed retrospectively. The hematopoietic reconstitution, graft verus host disease (GVHD), transplantation related toxicity (TRT) and prognosis after transplantation were compared. Furthermore, the modifed conditioning FC/ATG included low-dose cyclophosphamide (total dose 100 mg/kg), infustion of third-party donor-derived mesenchymal stem cells. All 56 patients with MSD-HSCT or HFD-HSCT achieved hematopoietic reconstitution. Among them, not only the recovery of neutrophils and platelets, but also the incidences of III-IV aGVHD, extensive cGVHD and TRT were not significantly different (the P value were 0.58, 0.61, 0.73, 0.73 and 0.67, respectively). After following-up for 32(2-66) months, 48 patients alive well, the 1-year overall survival rates were 86% in HFD-HSCT group and 89% in MSD-HSCT group, respectively (P=0.58). After HSCT using the modifed FC/ATG conditioning, patients with SAA achieved stable engraftment, low toxicity, mild GVHD and excellent outcomes. Furthermore, the HFD-HSCT achieved comparable outcomes to MSD-HSCT and may be served as an alternate therapy for patients with SAA.

  14. Antigen-specific and nonspecific mediators of T cell/B cell cooperation. III. Characterization of the nonspecific mediator(s) from different sources.

    PubMed

    Harwell, L; Kappler, J W; Marrack, P

    1976-05-01

    T cell-containing lymphoid populations produce a nonantigen-specific mediator(s) (NSM) which can replace T cell helper function in vitro in the response of B cells to sheep red blood cells (SRBC), but not to the hapten-protein conjugate, trinitrophenyl-keyhole limpet hemocyanin, (TNP-KLH). NSM produced under three conditions: 1) stimulation of KLH-primed cells with KLH; 2) allogeneic stimulation of normal spleen cells; and 3) stimulation of normal spleen cells with Con A (but not PHA) are indistinguishable on the basis of their biologic activity and m.w., estimated as 30 to 40,000 daltons by G-200 chromatography. Production of NSM is dependent on the presence of T cells. The action of NSM on B cells responding to SRBC in the presence of 2-mercaptoethanol is unaffected by severe macrophage depletion. Extensive absorption of NSM with SRBC failed to remove its activity, confirming its nonantigen-specific nature.

  15. Specific depletion of Ly6C(hi) inflammatory monocytes prevents immunopathology in experimental cerebral malaria.

    PubMed

    Schumak, Beatrix; Klocke, Katrin; Kuepper, Janina M; Biswas, Aindrila; Djie-Maletz, Andrea; Limmer, Andreas; van Rooijen, Nico; Mack, Matthias; Hoerauf, Achim; Dunay, Ildiko Rita

    2015-01-01

    Plasmodium berghei ANKA (PbA) infection of C57BL/6 mice leads to experimental cerebral malaria (ECM) that is commonly associated with serious T cell mediated damage. In other parasitic infection models, inflammatory monocytes have been shown to regulate Th1 responses but their role in ECM remains poorly defined, whereas neutrophils are reported to contribute to ECM immune pathology. Making use of the recent development of specific monoclonal antibodies (mAb), we depleted in vivo Ly6C(hi) inflammatory monocytes (by anti-CCR2), Ly6G+ neutrophils (by anti-Ly6G) or both cell types (by anti-Gr1) during infection with Ovalbumin-transgenic PbA parasites (PbTg). Notably, the application of anti-Gr1 or anti-CCR2 but not anti-Ly6G antibodies into PbTg-infected mice prevented ECM development. In addition, depletion of Ly6C(hi) inflammatory monocytes but not neutrophils led to decreased IFNγ levels and IFNγ+CD8+ T effector cells in the brain. Importantly, anti-CCR2 mAb injection did not prevent the generation of PbTg-specific T cell responses in the periphery, whereas anti-Gr1 mAb injection strongly diminished T cell frequencies and CTL responses. In conclusion, the specific depletion of Ly6C(hi) inflammatory monocytes attenuated brain inflammation and immune cell recruitment to the CNS, which prevented ECM following Plasmodium infection, pointing out a substantial role of Ly6C+ monocytes in ECM inflammatory processes.

  16. Roles of CD4+ T Cells and Gamma Interferon in Protective Immunity against Babesia microti Infection in Mice

    PubMed Central

    Igarashi, Ikuo; Suzuki, Reiko; Waki, Seiji; Tagawa, Yoh-Ichi; Seng, Seyha; Tum, Sothyra; Omata, Yoshitaka; Saito, Atsushi; Nagasawa, Hideyuki; Iwakura, Yohichiro; Suzuki, Naoyoshi; Mikami, Takeshi; Toyoda, Yutaka

    1999-01-01

    Babesia microti produces a self-limiting infection in mice, and recovered mice are resistant to reinfection. In the present study, the role of T cells in protective immunity against challenge infection was examined. BALB/c mice which recovered from primary infection showed strong protective immunity against challenge infection. In contrast, nude mice which failed to control the primary infection and were cured with an antibabesial drug did not show protection against challenge infection. Treatment of immune mice with anti-CD4 monoclonal antibody (MAb) diminished the protective immunity against challenge infection, but treatment with anti-CD8 MAb had no effect on the protection. Transfer of CD4+ T-cell-depleted spleen cells resulted in higher parasitemia than transfer of CD8+ T-cell-depleted spleen cells. A high level of gamma interferon (IFN-γ), which was produced by CD4+ T cells, was observed for the culture supernatant of spleen cells from immune mice, and treatment of immune mice with anti-IFN-γ MAb partially reduced the protection. Moreover, no protection against challenge infection was found in IFN-γ-deficient mice. On the other hand, treatment of immune mice with MAbs against interleukin-2 (IL-2), IL-4, or tumor necrosis factor alpha did not affect protective immunity. These results suggest essential requirements for CD4+ T cells and IFN-γ in protective immunity against challenge infection with B. microti. PMID:10417185

  17. CD4+ T-cell recovery with suppressive ART-induced rapid sequence evolution in hepatitis C virus envelope but not NS3.

    PubMed

    Liu, Lin; Nardo, David; Li, Eric; Wang, Gary P

    2016-03-13

    CD4 T-cell depletion from HIV infection leads to a global decline in anti-hepatitis C virus (HCV) envelope neutralizing antibody (nAb) response, which may play a role in accelerating liver fibrosis. An increase in anti-HCV nAb titers has been reported during antiretroviral therapy (ART) but its impact on HCV remains poorly understood. The objective of this study is to determine the effects of ART on long-term HCV evolution. We examined HCV quasispecies structure and long-term evolution in HIV/HCV coinfected patients with ART-induced CD4 T-cell recovery, and compared with patients with CD4 T-cell depletion from delayed ART. We applied a single-variant sequencing (SVS) method to construct authentic viral quasispecies and compared sequence evolution in HCV envelope, the primary target for humoral immune responses, and NS3, a target for cellular immunity, between the two cohorts. The SVS method corrected biases known to skew the proportions of viral variants, revealing authentic HCV quasispeices structures. We observed higher rates of HCV envelope sequence evolution in patients with ART-induced CD4 T-cell recovery, compared with patients with CD4 T-cell depletion from delayed ART (P = 0.03). Evolutionary rates for NS3 were considerably lower than the rates for envelope (P < 0.01), with no significant difference observed between the two groups. ART-induced CD4 T-cell recovery results in rapid sequence evolution in HCV envelope, but not in NS3. These results suggest that suppressive ART disproportionally enhances HCV-specific humoral responses more than cellular responses, resulting in rapid sequence evolution in HCV envelope but not NS3.

  18. Fatal autoimmune hepatitis induced by concurrent loss of naturally arising regulatory T cells and PD-1-mediated signaling.

    PubMed

    Kido, Masahiro; Watanabe, Norihiko; Okazaki, Taku; Akamatsu, Takuji; Tanaka, Junya; Saga, Kazuyuki; Nishio, Akiyoshi; Honjo, Tasuku; Chiba, Tsutomu

    2008-10-01

    Because of the lack of animal models developing spontaneous autoimmune hepatitis (AIH), the molecular mechanisms involved in the development of AIH are still unclear. This study aims to examine the regulatory roles of naturally arising CD4(+)CD25(+) regulatory T (Treg) cells and programmed cell death 1 (PD-1)-mediated signaling in the development of AIH. To induce a concurrent loss of Treg cells and PD-1-mediated signaling, neonatal thymectomy (NTx), which severely reduces the number of Treg cells, was performed on PD-1(-/-) mice. After the NTx, we performed histologic examination, assessed autoantibody production and infiltrating cells in the liver, and conducted adoptive transfer experiments. In contrast to NTx mice and PD-1(-/-) mice, NTx-PD-1(-/-) mice produced antinuclear antibodies and developed fatal hepatitis characterized by a CD4(+) and CD8(+) T-cell infiltration invading the parenchyma with massive lobular necrosis. Induction of AIH in NTx-PD-1(-/-) mice was suppressed by transfer of Treg cells, even derived from PD-1(-/-) mice. Transfer of total but not CD4(+) T-cell-depleted splenocytes from NTx-PD-1(-/-) mice into RAG2(-/-) mice induced the development of severe hepatitis. In contrast, the transfer of CD8(+) T-cell-depleted splenocytes triggered only mononuclear infiltrates without massive necrosis of the parenchyma. NTx-PD-1(-/-) mice are the first mouse model of spontaneous fatal AIH. The concurrent loss of Treg cells and PD-1-mediated signaling can induce the development of fatal AIH. Autoreactive CD4(+) T cells are essential for induction of AIH, whereas CD8(+) T cells play an important role in progression to fatal hepatic damage.

  19. Gamma-delta (γδ) T cells: friend or foe in cancer development?

    PubMed

    Zhao, Yijing; Niu, Chao; Cui, Jiuwei

    2018-01-10

    γδ T cells are a distinct subgroup of T cells containing T cell receptors (TCRs) γ and TCR δ chains with diverse structural and functional heterogeneity. As a bridge between the innate and adaptive immune systems, γδ T cells participate in various immune responses during cancer progression. Because of their direct/indirect antitumor cytotoxicity and strong cytokine production ability, the use of γδ T cells in cancer immunotherapy has received a lot of attention over the past decade. Despite the promising potential of γδ T cells, the efficacy of γδ T cell immunotherapy is limited, with an average response ratio of only 21%. In addition, research over the past 2 years has shown that γδ T cells could also promote cancer progression by inhibiting antitumor responses, and enhancing cancer angiogenesis. As a result, γδ T cells have a dual effect and can therefore be considered as being both "friends" and "foes" of cancer. In order to solve the sub-optimal efficiency problem of γδ T cell immunotherapy, we review recent observations regarding the antitumor and protumor activities of major structural and functional subsets of human γδ T cells, describing how these subsets are activated and polarized, and how these events relate to subsequent effects in cancer immunity. A mixture of both antitumor or protumor γδ T cells used in adoptive immunotherapy, coupled with the fact that γδ T cells can be polarized from antitumor cells to protumor cells appear to be the likely reasons for the mild efficacy seen with γδ T cells. The future holds the promise of depleting the specific protumor γδ T cell subgroup before therapy, choosing multi-immunocyte adoptive therapy, modifying the cytokine balance in the cancer microenvironment, and using a combination of γδ T cells adoptive immunotherapy with immune checkpoint inhibitors.

  20. Breaking immune tolerance by targeting Foxp3+ regulatory T cells mitigates Alzheimer's disease pathology

    PubMed Central

    Baruch, Kuti; Rosenzweig, Neta; Kertser, Alexander; Deczkowska, Aleksandra; Sharif, Alaa Mohammad; Spinrad, Amit; Tsitsou-Kampeli, Afroditi; Sarel, Ayelet; Cahalon, Liora; Schwartz, Michal

    2015-01-01

    Alzheimer's disease (AD) is a neurodegenerative disorder in which chronic neuroinflammation contributes to disease escalation. Nevertheless, while immunosuppressive drugs have repeatedly failed in treating this disease, recruitment of myeloid cells to the CNS was shown to play a reparative role in animal models. Here we show, using the 5XFAD AD mouse model, that transient depletion of Foxp3+ regulatory T cells (Tregs), or pharmacological inhibition of their activity, is followed by amyloid-β plaque clearance, mitigation of the neuroinflammatory response and reversal of cognitive decline. We further show that transient Treg depletion affects the brain's choroid plexus, a selective gateway for immune cell trafficking to the CNS, and is associated with subsequent recruitment of immunoregulatory cells, including monocyte-derived macrophages and Tregs, to cerebral sites of plaque pathology. Our findings suggest targeting Treg-mediated systemic immunosuppression for treating AD. PMID:26284939

  1. Signalling through NK1.1 triggers NK cells to die but induces NK T cells to produce interleukin-4.

    PubMed

    Asea, A; Stein-Streilein, J

    1998-02-01

    In vivo inoculation of specific antibody is an accepted protocol for elimination of specific cell populations. Except for anti-CD3 and anti-CD4, it is not known if the depleted cells are eliminated by signalling through the target molecule or through a more non-specific mechanism. C57BL/6 mice were inoculated with anti-natural killer (NK1.1) monoclonal antibody (mAb). Thereafter spleen cells were harvested, stained for both surface and intracellular markers, and analysed by flow cytometry. As early as 2 hr post inoculation, NK cells were signalled to become apoptotic while signalling through the NK1.1 molecule activated NK1.1+ T-cell receptor (TCR)+ (NK T) cells to increase in number, and produce interleukin-4 (IL-4). Anti NK1.1 mAb was less efficient at signalling apoptosis in NK cells when NK T-cell deficient [beta 2-microglobulin beta 2m-deficient] mice were used compared with wild type mice. Efficient apoptotic signalling was restored when beta 2m-deficient mice were reconstituted with NK T cells. NK-specific antibody best signals the apoptotic process in susceptible NK cells when resistant NK T cells are present, activated, and secrete IL-4.

  2. Antiviral therapy during primary simian immunodeficiency virus infection fails to prevent acute loss of CD4+ T cells in gut mucosa but enhances their rapid restoration through central memory T cells.

    PubMed

    Verhoeven, David; Sankaran, Sumathi; Silvey, Melanie; Dandekar, Satya

    2008-04-01

    Gut-associated lymphoid tissue (GALT) is an early target of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) and a site for severe CD4+ T-cell depletion. Although antiretroviral therapy (ART) is effective in suppressing HIV replication and restoring CD4+ T cells in peripheral blood, restoration in GALT is delayed. The role of restored CD4+ T-cell help in GALT during ART and its impact on antiviral CD8+ T-cell responses have not been investigated. Using the SIV model, we investigated gut CD4+ T-cell restoration in infected macaques, initiating ART during either the primary stage (1 week postinfection), prior to acute CD4+ cell loss (PSI), or during the chronic stage at 10 weeks postinfection (CSI). ART led to viral suppression in GALT and peripheral blood mononuclear cells of PSI and CSI animals at comparable levels. CSI animals had incomplete CD4+ T-cell restoration in GALT. In PSI animals, ART did not prevent acute CD4+ T-cell loss by 2 weeks postinfection in GALT but supported rapid and complete CD4+ T-cell restoration thereafter. This correlated with an accumulation of central memory CD4+ T cells and better suppression of inflammation. Restoration of CD4+ T cells in GALT correlated with qualitative changes in SIV gag-specific CD8+ T-cell responses, with a dominance of interleukin-2-producing responses in PSI animals, while both CSI macaques and untreated SIV-infected controls were dominated by gamma interferon responses. Thus, central memory CD4+ T-cell levels and qualitative antiviral CD8+ T-cell responses, independent of viral suppression, were the immune correlates of gut mucosal immune restoration during ART.

  3. Evidence that Singlet Oxygen-induced Human T Helper Cell Apoptosis Is the Basic Mechanism of Ultraviolet-A Radiation Phototherapy

    PubMed Central

    Morita, Akimichi; Werfel, Thomas; Stege, Helger; Ahrens, Constanze; Karmann, Karin; Grewe, Markus; Grether-Beck, Susanne; Ruzicka, Thomas; Kapp, Alexander; Klotz, Lars-Oliver; Sies, Helmut; Krutmann, Jean

    1997-01-01

    Ultraviolet A (UVA) irradiation is effectively used to treat patients with atopic dermatitis and other T cell mediated, inflammatory skin diseases. In the present study, successful phototherapy of atopic dermatitis was found to result from UVA radiation-induced apoptosis in skin-infiltrating T helper cells, leading to T cell depletion from eczematous skin. In vitro, UVA radiation-induced human T helper cell apoptosis was mediated through the FAS/FAS-ligand system, which was activated in irradiated T cells as a consequence of singlet oxygen generation. These studies demonstrate that singlet oxygen is a potent trigger for the induction of human T cell apoptosis. They also identify singlet oxygen generation as a fundamental mechanism of action operative in phototherapy. PMID:9362536

  4. IDO and galectin-3 hamper the ex vivo generation of clinical grade tumor-specific T cells for adoptive cell therapy in metastatic melanoma.

    PubMed

    Melief, Sara M; Visser, Marten; van der Burg, Sjoerd H; Verdegaal, Els M E

    2017-07-01

    Adoptive T cell transfer (ACT) with ex vivo-expanded tumor-reactive T cells proved to be successful for the treatment of metastatic melanoma patients. Mixed lymphocyte tumor cell cultures (MLTC) can be used to generate tumor-specific T cells for ACT; however, in a number of cases tumor-reactive T cell, expansion is far from optimal. We hypothesized that this is due to tumor intrinsic and extrinsic factors and aimed to identify and manipulate these factors so to optimize our clinical, GMP-compliant MLTC protocol. We found that the tumor cell produced IDO and/or galectin-3, and the accumulation of CD4 + CD25 hi FoxP3 + T cells suppressed the expansion of tumor-specific T cells in the MLTC. Strategies to eliminate CD4 + CD25 hi FoxP3 + T cells during culture required the depletion of the whole CD4 + T cell population and were found to be undesirable. Blocking of IDO and galectin-3 was feasible and resulted in improved efficiency of the MLTC. Implementation of these findings in clinical protocols for ex vivo expansion of tumor-reactive T cells holds promise for an increased therapeutic potential of adoptive cell transfer treatments with tumor-specific T cells.

  5. Expression of Master Regulators of T-cell, Helper T-cell and Follicular Helper T-cell Differentiation in Angioimmunoblastic T-cell Lymphoma.

    PubMed

    Matsumoto, Yosuke; Nagoshi, Hisao; Yoshida, Mihoko; Kato, Seiichi; Kuroda, Junya; Shimura, Kazuho; Kaneko, Hiroto; Horiike, Shigeo; Nakamura, Shigeo; Taniwaki, Masafumi

    2017-11-01

    Objective It has been postulated that the normal counterpart of angioimmunoblastic T-cell lymphoma (AITL) is the follicular helper T-cell (TFH). Recent immunological studies have identified several transcription factors responsible for T-cell differentiation. The master regulators associated with T-cell, helper T-cell (Th), and TFH differentiation are reportedly BCL11B, Th-POK, and BCL6, respectively. We explored the postulated normal counterpart of AITL with respect to the expression of the master regulators of T-cell differentiation. Methods We performed an immunohistochemical analysis in 15 AITL patients to determine the expression of the master regulators and several surface markers associated with T-cell differentiation. Results BCL11B was detected in 10 patients (67%), and the surface marker of T-cells (CD3) was detected in all patients. Only 2 patients (13%) expressed the marker of naïve T-cells (CD45RA), but all patients expressed the marker of effector T-cells (CD45RO). Nine patients expressed Th-POK (60%), and 7 (47%) expressed a set of surface antigens of Th (CD4-positive and CD8-negative). In addition, BCL6 and the surface markers of TFH (CXCL13, PD-1, and SAP) were detected in 11 (73%), 8 (53%), 14 (93%), and all patients, respectively. Th-POK-positive/BCL6-negative patients showed a significantly shorter overall survival (OS) than the other patients (median OS: 33.0 months vs. 74.0 months, p=0.020; log-rank test). Conclusion Many of the AITL patients analyzed in this study expressed the master regulators of T-cell differentiation. The clarification of the diagnostic significance and pathophysiology based on the expression of these master regulators in AITL is expected in the future.

  6. Variable effects of the mitoK(ATP) channel modulators diazoxide and 5-HD in ATP-depleted renal epithelial cells.

    PubMed

    Nilakantan, Vani; Liang, Huanling; Mortensen, Jordan; Taylor, Erin; Johnson, Christopher P

    2010-02-01

    The role of mitochondrial K(ATP) (mitoK(ATP)) channels in renal ischemia-reperfusion injury is controversial with studies showing both protective and deleterious effects. In this study, we compared the effects of the putative mitoK(ATP) opener, diazoxide, and the mitoK(ATP) blocker, 5-hydroxydecanoate (5-HD) on cytotoxicity and apoptosis in tubular epithelial cells derived from rat (NRK-52E) and pig (LLC-PK1) following in vitro ischemic injury. Following ATP depletion-recovery, there was a significant increase in cytotoxicity in both NRK cells and LLC-PK1 cells although NRK cells were more sensitive to the injury. Diazoxide treatment attenuated cytotoxicity in both cell types and 5-HD treatment-increased cytotoxicity in the sensitive NRK cells in a superoxide-dependant manner. The protective effect of diazoxide was also reversed in the presence of 5-HD in ATP-depleted NRK cells. The ATP depletion-mediated increase in superoxide was enhanced by both diazoxide and 5-HD with the effect being more pronounced in the cells undergoing 5-HD treatment. Further, ATP depletion-induced activation of caspase-3 was decreased by diazoxide in NRK cells. In order to determine the signaling pathways involved in apoptosis, we examined the activation of Erk and JNK in ATP-depleted NRK cells. Diazoxide-activated Erk in ATP-depleted cells, but did not have any effect on JNK activation. In contrast, 5-HD did not impact Erk levels but increased JNK activation even under controlled conditions. Further, the use of a JNK inhibitor with 5-HD reversed the deleterious effects of 5-HD. This study demonstrates that in cells that are sensitive to ATP depletion-recovery, mitoK(ATP) channels protect against ATP depletion-mediated cytotoxicity and apoptosis through Erk- and JNK-dependant mechanisms.

  7. Antibody response against Betaferon® in immune tolerant mice: involvement of marginal zone B-cells and CD4+ T-cells and apparent lack of immunological memory.

    PubMed

    Sauerborn, Melody; van Beers, Miranda M C; Jiskoot, Wim; Kijanka, Grzegorz M; Boon, Louis; Schellekens, Huub; Brinks, Vera

    2013-01-01

    The immunological processes underlying immunogenicity of recombinant human therapeutics are poorly understood. Using an immune tolerant mouse model we previously demonstrated that aggregates are a major trigger of the antidrug antibody (ADA) response against recombinant human interferon beta (rhIFNβ) products including Betaferon®, and that immunological memory seems to be lacking after a rechallenge with non-aggregated rhIFNβ. The apparent absence of immunological memory indicates a CD4+ T-cell independent (Tind) immune response underlying ADA formation against Betaferon®. This hypothesis was tested. Using the immune tolerant mouse model we first validated that rechallenge with highly aggregated rhIFNβ (Betaferon®) does not lead to a subsequent fast increase in ADA titers, suggesting a lack of immunological memory. Next we assessed whether Betaferon® could act as Tind antigen by inactivation of marginal zone (MZ) B-cells during treatment. MZ B-cells are major effector cells involved in a Tind immune response. In a following experiment we depleted the mice from CD4+ T-cells to test their involvement in the ADA response against Betaferon®. Inactivation of MZ B-cells at the start of Betaferon® treatment drastically lowered ADA levels, suggesting a Tind immune response. However, persistent depletion of CD4+ T-cells before and during Betaferon® treatment abolished the ADA response in almost all mice. The immune response against rhIFNβ in immune tolerant mice is neither a T-cell independent nor a classical T-cell dependent immune response. Further studies are needed to confirm absence of immunological memory (cells).

  8. Donor-derived CD19-targeted T cells cause regression of malignancy persisting after allogeneic hematopoietic stem cell transplantation

    PubMed Central

    Dudley, Mark E.; Carpenter, Robert O.; Kassim, Sadik H.; Rose, Jeremy J.; Telford, William G.; Hakim, Frances T.; Halverson, David C.; Fowler, Daniel H.; Hardy, Nancy M.; Mato, Anthony R.; Hickstein, Dennis D.; Gea-Banacloche, Juan C.; Pavletic, Steven Z.; Sportes, Claude; Maric, Irina; Feldman, Steven A.; Hansen, Brenna G.; Wilder, Jennifer S.; Blacklock-Schuver, Bazetta; Jena, Bipulendu; Bishop, Michael R.; Gress, Ronald E.; Rosenberg, Steven A.

    2013-01-01

    New treatments are needed for B-cell malignancies persisting after allogeneic hematopoietic stem cell transplantation (alloHSCT). We conducted a clinical trial of allogeneic T cells genetically modified to express a chimeric antigen receptor (CAR) targeting the B-cell antigen CD19. T cells for genetic modification were obtained from each patient’s alloHSCT donor. All patients had malignancy that persisted after alloHSCT and standard donor lymphocyte infusions (DLIs). Patients did not receive chemotherapy prior to the CAR T-cell infusions and were not lymphocyte depleted at the time of the infusions. The 10 treated patients received a single infusion of allogeneic anti-CD19-CAR T cells. Three patients had regressions of their malignancies. One patient with chronic lymphocytic leukemia (CLL) obtained an ongoing complete remission after treatment with allogeneic anti-CD19-CAR T cells, another CLL patient had tumor lysis syndrome as his leukemia dramatically regressed, and a patient with mantle cell lymphoma obtained an ongoing partial remission. None of the 10 patients developed graft-versus-host disease (GVHD). Toxicities included transient hypotension and fever. We detected cells containing the anti-CD19-CAR gene in the blood of 8 of 10 patients. These results show for the first time that donor-derived allogeneic anti-CD19-CAR T cells can cause regression of B-cell malignancies resistant to standard DLIs without causing GVHD. This trial was registered at www.clinicaltrials.gov as #NCT01087294. PMID:24055823

  9. Effective collaboration between marginal metallophilic macrophages and CD8+ dendritic cells in the generation of cytotoxic T cells

    PubMed Central

    Backer, Ronald; Schwandt, Timo; Greuter, Mascha; Oosting, Marije; Jüngerkes, Frank; Tüting, Thomas; Boon, Louis; O’Toole, Tom; Kraal, Georg; Limmer, Andreas; den Haan, Joke M. M.

    2009-01-01

    The spleen is the lymphoid organ that induces immune responses toward blood-borne pathogens. Specialized macrophages in the splenic marginal zone are strategically positioned to phagocytose pathogens and cell debris, but are not known to play a role in the activation of T-cell responses. Here we demonstrate that splenic marginal metallophilic macrophages (MMM) are essential for cross-presentation of blood-borne antigens by splenic dendritic cells (DCs). Our data demonstrate that antigens targeted to MMM as well as blood-borne adenoviruses are efficiently captured by MMM and exclusively transferred to splenic CD8+ DCs for cross-presentation and for the activation of cytotoxic T lymphocytes. Depletion of macrophages in the marginal zone prevents cytotoxic T-lymphocyte activation by CD8+ DCs after antibody targeting or adenovirus infection. Moreover, we show that tumor antigen targeting to MMM is very effective as antitumor immunotherapy. Our studies point to an important role for splenic MMM in the initial steps of CD8+ T-cell immunity by capturing and concentrating blood-borne antigens and the transfer to cross-presenting DCs which can be used to design vaccination strategies to induce antitumor cytotoxic T-cell immunity. PMID:20018690

  10. Of mice and men: how animal models advance our understanding of T-cell function in RA.

    PubMed

    Kobezda, Tamás; Ghassemi-Nejad, Sheida; Mikecz, Katalin; Glant, Tibor T; Szekanecz, Zoltán

    2014-03-01

    The involvement of autoreactive T cells in the pathogenesis of rheumatoid arthritis (RA) as well as in autoimmune animal models of arthritis has been well established; however, unanswered questions, such as the role of joint-homing T cells, remain. Animal models of arthritis are superb experimental tools in demonstrating how T cells trigger joint inflammation, and thus can help to further our knowledge of disease mechanisms and potential therapies. In this Review, we discuss the similarities and differences in T-cell subsets and functions between RA and mouse arthritis models. For example, various T-cell subsets are involved in both human and mouse arthritis, but differences might exist in the cytokine regulation and plasticity of these cells. With regard to joint-homing T cells, an abundance of synovial T cells is present in humans compared with mice. On the other hand, local expansion of type 17 T-helper (TH17) cells is observed in some animal models, but not in RA. Finally, whereas T-cell depletion therapy essentially failed in RA, antibody targeting of T cells can work, at least preventatively, in most arthritis models. Clearly, additional human and animal studies are needed to fill the gap in our understanding of the specific contribution of T-cell subsets to arthritis in mice and men.

  11. Components of Streptococcus pneumoniae suppress allergic airways disease and NKT cells by inducing regulatory T cells.

    PubMed

    Thorburn, Alison N; Foster, Paul S; Gibson, Peter G; Hansbro, Philip M

    2012-05-01

    Asthma is an allergic airways disease (AAD) caused by dysregulated immune responses and characterized by eosinophilic inflammation, mucus hypersecretion, and airway hyperresponsiveness (AHR). NKT cells have been shown to contribute to AHR in some mouse models. Conversely, regulatory T cells (Tregs) control aberrant immune responses and maintain homeostasis. Recent evidence suggests that Streptococcus pneumoniae induces Tregs that have potential to be harnessed therapeutically for asthma. In this study, mouse models of AAD were used to identify the S. pneumoniae components that have suppressive properties, and the mechanisms underlying suppression were investigated. We tested the suppressive capacity of type-3-polysaccharide (T3P), isolated cell walls, pneumolysoid (Ply) and CpG. When coadministered, T3P + Ply suppressed the development of: eosinophilic inflammation, Th2 cytokine release, mucus hypersecretion, and AHR. Importantly, T3P + Ply also attenuated features of AAD when administered during established disease. We show that NKT cells contributed to the development of AAD and also were suppressed by T3P + Ply treatment. Furthermore, adoptive transfer of NKT cells induced AHR, which also could be reversed by T3P + Ply. T3P + Ply-induced Tregs were essential for the suppression of NKT cells and AAD, which was demonstrated by Treg depletion. Collectively, our results show that the S. pneumoniae components T3P + Ply suppress AAD through the induction of Tregs that blocked the activity of NKT cells. These data suggest that S. pneumoniae components may have potential as a therapeutic strategy for the suppression of allergic asthma through the induction of Tregs and suppression of NKT cells.

  12. Expansion of natural killer cell receptor (CD94/NKG2A)-expressing cytolytic CD8 T cells and CD4+CD25+ regulatory T cells from the same cord blood unit.

    PubMed

    Tanaka, Junji; Sugita, Junichi; Kato, Naoko; Toubai, Tomomi; Ibata, Makoto; Shono, Yusuke; Ota, Shuichi; Kondo, Takeshi; Kobayashi, Takahiko; Kobayashi, Masanobu; Asaka, Masahiro; Imamura, Masahiro

    2007-10-01

    Cord blood contains a significant number of precursor cells that differentiate to cytotoxic effector cells and immunoregulatory cells. We tried to expand inhibitory natural killer cell receptor CD94-expressing CD8 T cells with cytolytic activity and CD4(+)CD25(+) regulatory T cells from the same cord cell unit. Cytotoxic CD94-expressing CD8 T cells were expanded from CD4-depleted cord blood using an immobilized anti-CD3 monoclonal antibody and a cytokine and also CD4(+)CD25(+) regulatory T cells were expanded from a CD4-enriched fraction derived from the same cord blood unit using anti-CD3/CD28 monoclonal antibody-coated Dynabeads and cytokines. We were able to obtain a more than 1000-fold expansion of CD94-expressing CD8 T cells and a more than 50-fold expansion of CD4(+)CD25(+) cells from the same cord blood unit. These expanded CD4(+)CD25(+) cells expressed FoxP3 mRNA at a level about 100-fold higher than that in isolated CD25(-) cells and could suppress allogeneic mixed lymphocyte culture by >80% (effector cells: CD4(+)CD25(+) cells = 2:1). Cytolytic activities of purified CD94-expressing cells detected by a 4-hour (51)Cr release assay against K562 were >60%. Coculture of CD94-expressing cells with expanded CD4(+)CD25(+) cells did not have any effect on cytolytic activities of purified CD94-expressing cells against K562 cells. These expanded cytolytic CD94-expressing CD8 cells might be able to induce a graft-vs-leukemia effect without enhancing graft-vs-host disease, and CD4(+)CD25(+) cells might be able to suppress allogeneic responses, including graft-vs-host disease and graft rejection after cord blood transplantation.

  13. Antibody induced CD4 down-modulation of T cells is site-specifically mediated by CD64+ cells

    PubMed Central

    Vogel, Stephanie; Grabski, Elena; Buschjäger, Daniela; Klawonn, Frank; Döring, Marius; Wang, Junxi; Fletcher, Erika; Bechmann, Ingo; Witte, Torsten; Durisin, Martin; Schraven, Burkhart; Mangsbo, Sara M.; Schönfeld, Kurt; Czeloth, Niklas; Kalinke, Ulrich

    2015-01-01

    Treatment of PBMC with the CD4-specific mAb BT-061 induces CD4 down-modulation of T cells. Here we report that addition of BT-061 to purified T cells did not confer this effect, whereas incubation of T cells in BT-061 coated wells restored CD4 down-modulation. These results implied that Fcγ receptor mediated cell-cell interactions played a role. In consistence with this hypothesis PBMC depleted of CD64+ monocytes did not confer CD4 down-modulation of BT-061 decorated T cells. Strikingly, CD4 down-modulation was observed in BT-061 treated synovial fluid punctuated from patients’ inflamed joints that comprised enhanced numbers of CD64+ cells. In contrast, in a circulating whole blood system injection of BT-061 did not induce CD4 down-modulation, due to CD64 saturation by serum IgG. Similarly, tonsil derived mononuclear cells devoid of CD64+ cells did not show CD4 down-modulation, whereas addition of blood derived monocytes restored the effect. Thus, the interaction of BT-061 decorated T cells with CD64+ cells is needed for CD4 down-modulation, implying that in patients BT-061 would primarily induce CD4 down-modulation at inflammatory sites. These results highlight the need not only to examine the interaction of a given mAb with single FcγR, but also the immunological environment that is appropriate to support such interactions. PMID:26670584

  14. The role of accessory cells in polyclonal T cell activation. I. Both induction of interleukin 2 production and of interleukin 2 responsiveness by concanavalin A are accessory cell dependent.

    PubMed

    Hünig, T; Loos, M; Schimpl, A

    1983-01-01

    Recent studies from other laboratories have shown that concanavalin A (Con A) acts at two separate steps in polyclonal T cell activation: interleukin 2 (IL2) production, and induction of responsiveness to IL2. Using a combination of techniques for the depletion of accessory cells from lymph node T cells, we have investigated which of these steps, if not both, is responsible for the known requirement for accessory cells in the Con A response. It was found that with increasing T cell purification, first the ability is lost to produce sufficient levels of endogenous IL2, whereas induction of IL2 responsiveness can still take place. Further removal of accessory cells however yields a population of resting T cells that cannot be induced by Con A to become IL2-reactive. It was concluded that both IL2 production and induction of reactivity to IL2 are accessory cell-dependent events.

  15. Metronomic cyclophosphamide eradicates large implanted GL261 gliomas by activating antitumor Cd8+ T-cell responses and immune memory

    PubMed Central

    Wu, Junjie; Waxman, David J

    2015-01-01

    Cancer chemotherapy using cytotoxic drugs can induce immunogenic tumor cell death; however, dosing regimens and schedules that enable single-agent chemotherapy to induce adaptive immune-dependent ablation of large, established tumors with activation of long-term immune memory have not been identified. Here, we investigate this issue in a syngeneic, implanted GL261 glioma model in immune-competent mice given cyclophosphamide on a 6-day repeating metronomic schedule. Two cycles of metronomic cyclophosphamide treatment induced sustained upregulation of tumor-associated CD8+ cytotoxic T lymphocyte (CTL) cells, natural killer (NK) cells, macrophages, and other immune cells. Expression of CTL- and NK–cell-shared effectors peaked on Day 6, and then declined by Day 9 after the second cyclophosphamide injection and correlated inversely with the expression of the regulatory T cell (Treg) marker Foxp3. Sustained tumor regression leading to tumor ablation was achieved after several cyclophosphamide treatment cycles. Tumor ablation required CD8+ T cells, as shown by immunodepletion studies, and was associated with immunity to re-challenge with GL261 glioma cells, but not B16-F10 melanoma or Lewis lung carcinoma cells. Rejection of GL261 tumor re-challenge was associated with elevated CTLs in blood and increased CTL infiltration in tumors, consistent with the induction of long-term, specific CD8+ T-cell anti-GL261 tumor memory. Co-depletion of CD8+ T cells and NK cells did not inhibit tumor regression beyond CD8+ T-cell depletion alone, suggesting that the metronomic cyclophosphamide-activated NK cells function via CD8a+ T cells. Taken together, these findings provide proof-of-concept that single-agent chemotherapy delivered on an optimized metronomic schedule can eradicate large, established tumors and induce long-term immune memory. PMID:26137402

  16. Transfer of minimally manipulated CMV-specific T cells from stem cell or third-party donors to treat CMV infection after allo-HSCT.

    PubMed

    Neuenhahn, M; Albrecht, J; Odendahl, M; Schlott, F; Dössinger, G; Schiemann, M; Lakshmipathi, S; Martin, K; Bunjes, D; Harsdorf, S; Weissinger, E M; Menzel, H; Verbeek, M; Uharek, L; Kröger, N; Wagner, E; Kobbe, G; Schroeder, T; Schmitt, M; Held, G; Herr, W; Germeroth, L; Bonig, H; Tonn, T; Einsele, H; Busch, D H; Grigoleit, G U

    2017-10-01

    Cytomegalovirus (CMV) infection is a common, potentially life-threatening complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT). We assessed prospectively the safety and efficacy of stem cell-donor- or third-party-donor-derived CMV-specific T cells for the treatment of persistent CMV infections after allo-HSCT in a phase I/IIa trial. Allo-HSCT patients with drug-refractory CMV infection and lacking virus-specific T cells were treated with a single dose of ex vivo major histocompatibility complex-Streptamer-isolated CMV epitope-specific donor T cells. Forty-four allo-HSCT patients receiving a T-cell-replete (D + repl; n=28) or T-cell-depleted (D + depl; n=16) graft from a CMV-seropositive donor were screened for CMV-specific T-cell immunity. Eight D + depl recipients received adoptive T-cell therapy from their stem cell donor. CMV epitope-specific T cells were well supported and became detectable in all treated patients. Complete and partial virological response rates were 62.5% and 25%, respectively. Owing to longsome third-party donor (TPD) identification, only 8 of the 57 CMV patients transplanted from CMV-seronegative donors (D - ) received antigen-specific T cells from partially human leukocyte antigen (HLA)-matched TPDs. In all but one, TPD-derived CMV-specific T cells remained undetectable. In summary, adoptive transfer correlated with functional virus-specific T-cell reconstitution in D + depl patients. Suboptimal HLA match may counteract expansion of TPD-derived virus-specific T cells in D - patients.

  17. Role of the Ca2+-Calcineurin-Nuclear Factor of Activated T cell Pathway in Mitofusin-2-Mediated Immune Function of Jurkat Cells.

    PubMed

    Xu, Xiu-Ping; Yao, Yong-Ming; Zhao, Guang-Ju; Wu, Zong-Sheng; Li, Jun-Cong; Jiang, Yun-Long; Lu, Zhong-Qiu; Hong, Guang-Liang

    2018-02-05

    Mitofusin-2 (MFN2), a well-known mitochondrial fusion protein, has been shown to participate in innate immunity, but its role in mediating adaptive immunity remains poorly characterized. In this study, we explored the potential role of MFN2 in mediating the immune function of T lymphocytes. We manipulated MFN2 gene expression in Jurkat cells via lentiviral transduction of MFN2 small interfering RNA (siRNA) or full-length MFN2. After transduction, the immune response and its underlying mechanism were determined in Jurkat cells. One-way analysis of variance and Student's t-test were performed to determine the statistical significance between the groups. Overexpression of MFN2 enhanced the immune response of T lymphocytes by upregulating Ca2+ (359.280 ± 10.130 vs. 266.940 ± 10.170, P = 0.000), calcineurin (0.513 ± 0.014 vs. 0.403 ± 0.020 nmol/L, P = 0.024), and nuclear factor of activated T cells (NFATs) activation (1.040 ± 0.086 vs. 0.700 ± 0.115, P = 0.005), whereas depletion of MFN2 impaired the immune function of T lymphocytes by downregulating Ca2+ (141.140 ± 14.670 vs. 267.060 ± 9.230, P = 0.000), calcineurin (0.054 ± 0.030 nmol/L vs. 0.404 ± 0.063 nmol/L, P = 0.000), and NFAT activation (0.500 ± 0.025 vs. 0.720 ± 0.061, P = 0.012). Furthermore, upregulated calcineurin partially reversed the negative effects of MFN2 siRNA on T cell-mediated immunity evidenced by elevations in T cell proliferation (1.120 ± 0.048 vs. 0.580 ± 0.078, P = 0.040), interleukin-2 (IL-2) production (473.300 ± 24.100 vs. 175.330 ± 12.900 pg/ml, P = 0.000), and the interferon-γ/IL-4 ratio (3.080 ± 0.156 vs. 0.953 ± 0.093, P = 0.000). Meanwhile, calcineurin activity inhibitor depleted the positive effects of overexpressed MFN2 on T cells function. Our findings suggest that MFN2 may regulate T cell immune functions primarily through the Ca2+-calcineurin-NFAT pathway. MFN2 may represent a potential therapeutic target for T cell immune dysfunction-related diseases.

  18. Development of Augmented Leukemia/Lymphoma-Specific T-Cell Immunotherapy for Deployment with Haploidentical, Hematompoietic Progenitor-Cell Transplant

    DTIC Science & Technology

    2011-05-01

    Alliance for Cancer Gene Therapy ; Amy Phillips Charitable Foundation; The Leukemia and Lymphoma Society; Lymphoma Research Foundation; National Foundation...Y, Preffer FI, et al. Treatment of plasma cell dyscrasias by antibody-mediated immuno- therapy . Semin Oncol 1999;26:97–106. 15. Zhao S , Asgary Z...cell-transfer therapy for the treatment of patients with cancer. Nat Rev Cancer 2003;3:666–75. 25. Gillies SD, Lan Y, Williams S , et al. An anti-CD20

  19. Innate Effector-Memory T-Cell Activation Regulates Post-Thrombotic Vein Wall Inflammation and Thrombus Resolution.

    PubMed

    Luther, Natascha; Shahneh, Fatemeh; Brähler, Melanie; Krebs, Franziska; Jäckel, Sven; Subramaniam, Saravanan; Stanger, Christian; Schönfelder, Tanja; Kleis-Fischer, Bettina; Reinhardt, Christoph; Probst, Hans Christian; Wenzel, Philip; Schäfer, Katrin; Becker, Christian

    2016-12-09

    Immune cells play an important role during the generation and resolution of thrombosis. T cells are powerful regulators of immune and nonimmune cell function, however, their role in sterile inflammation in venous thrombosis has not been systematically examined. This study investigated the recruitment, activation, and inflammatory activity of T cells in deep vein thrombosis and its consequences for venous thrombus resolution. CD4 + and CD8 + T cells infiltrate the thrombus and vein wall rapidly on deep vein thrombosis induction and remain in the tissue throughout the thrombus resolution. In the vein wall, recruited T cells largely consist of effector-memory T (T EM ) cells. Using T-cell receptor transgenic reporter mice, we demonstrate that deep vein thrombosis-recruited T EM receive an immediate antigen-independent activation and produce IFN-γ (interferon) in situ. Mapping inflammatory conditions in the thrombotic vein, we identify a set of deep vein thrombosis upregulated cytokines and chemokines that synergize to induce antigen-independent IFN-γ production in CD4 + and CD8 + T EM cells. Reducing the number of T EM cells through a depletion recovery procedure, we show that intravenous T EM activation determines neutrophil and monocyte recruitment and delays thrombus neovascularization and resolution. Examining T-cell recruitment in human venous stasis, we show that superficial varicose veins preferentially contain activated memory T cells. T EM orchestrate the inflammatory response in venous thrombosis affecting thrombus resolution. © 2016 American Heart Association, Inc.

  20. HIV envelope-mediated, CCR5/α4β7-dependent killing of CD4-negative γδ T cells which are lost during progression to AIDS.

    PubMed

    Li, Haishan; Pauza, C David

    2011-11-24

    HIV infects and replicates in CD4+ T cells but effects on host immunity and disease also involve depletion, hyper-activation, and modification of CD4-negative cell populations. In particular, the depletion of CD4-negative γδ T cells is common to all HIV+ individuals. We found that soluble or cell-associated envelope glycoproteins from CCR5-tropic strains of HIV could bind, activates the p38-caspase pathway, and induce the death of γδ cells. Envelope binding requires integrin α4β7 and chemokine receptor CCR5 which are at high levels and form a complex on the γδ T cell membrane. This receptor complex facilitated V3 loop binding to CCR5 in the absence of CD4-induced conformational changes. Cell death was increased by antigen stimulation after exposure to envelope glycoprotein. Direct signaling by envelope glycoprotein killed CD4-negative γδ T cells and reproduced a defect observed in all patients with HIV disease.

  1. Contrasting acute graft-versus-host disease effects of Tim-3/galectin-9 pathway blockade dependent upon the presence of donor regulatory T cells

    PubMed Central

    Veenstra, Rachelle G.; Taylor, Patricia A.; Zhou, Qing; Panoskaltsis-Mortari, Angela; Hirashima, Mitsuomi; Flynn, Ryan; Liu, Derek; Anderson, Ana C.; Strom, Terry B.; Kuchroo, Vijay K.

    2012-01-01

    T-cell immunoglobulin mucin-3 (Tim-3) is expressed on pathogenic T cells, and its ligand galectin-9 (gal-9) is up-regulated in inflamed tissues. When Tim-3+ T cells encounter high gal-9 levels, they are deleted. Tim-3 is up-regulated on activated T cells during GVHD. Inhibition of Tim-3/gal-9 binding by infusion of a Tim-3-Ig fusion protein or Tim-3−/− donor T cells increased T-cell proliferation and GVHD lethality. When the Tim-3/gal-9 pathway engagement was augmented using gal-9 transgenic recipients, GVHD lethality was slowed. Together, these data indicate a potential for modulating this pathway to reduce disease by increasing Tim-3 or gal-9 engagement. Paradoxically, when Tim-3/gal-9 was inhibited in the absence of donor T-regulatory cells (Tregs), GVHD was inhibited. GVHD reduction was associated with decreased colonic inflammatory cytokines as well as epithelial barrier destruction. CD25-depleted Tim-3−/− donor T cells underwent increased activation-induced cell death because of increased IFN-γ production. To our knowledge, these studies are the first to show that although the absence of Tim-3/gal-9 pathway interactions augments systemic GVHD, concurrent donor Treg depletion paradoxically and surprisingly inhibits GVHD. Thus, although donor Tregs typically inhibit GVHD, under some conditions, such Tregs actually may contribute to GVHD by reducing activation-induced T-cell death. PMID:22677125

  2. HIV-1 DNA burden dynamics in CD4 T cells and monocytes in patients undergoing a transient therapy interruption.

    PubMed

    Garbuglia, Anna Rosa; Calcaterra, Silvia; D'Offizi, Gianpiero; Topino, Simone; Narciso, Pasquale; Lillo, Flavia; Girardi, Enrico; Capobianchi, Maria Rosaria

    2004-11-01

    Replication-competent HIV, as well as HIV-1 DNA, has been detected in CD4 T cells and in monocytes during antiretroviral therapy (ART), indicating that these cells could represent an important viral reservoir. We measured HIV-1 DNA in monocytes and CD4 T cells in patients undergoing transient therapy interruption (TTI), to establish the dynamic of HIV-1 DNA burden and to find possible correlations with immune restoration and re-establishment of virological control after ART resumption. In most patients CD4 depletion and viral load rebound followed TTI. Rapid resumption of virological and immunological control was achieved after ART reintroduction. After TTI, in most cases a transient increase of both monocyte and CD4 HIV-1 DNA burden was observed. After ART reintroduction, both CD4 T cell and monocyte HIV-1 DNA copy number decreased, reaching baseline levels at the end of observation. At this time monocyte HIV-1 DNA burden was always undetectable, while CD4 T cell HIV-1 DNA burden was lower than at baseline. As CD4 T cell HIV-1 DNA values are independently associated with CD4 depletion, the increase of HIV-1 DNA burden in these cells after TTI is presumably due to acute infection, causing cell death. This is also supported by the pattern of 2-LTR appearance in these cells after TTI. HIV-1 DNA burden in monocytes and CD4 T cells show high correlation, suggesting reciprocal re-feeding of two cell populations. Repopulation by HIV these cells after TTI is temporary, and no significant changes of HIV-1 DNA burden were observed after ART resumption respect to pre-TTI period.

  3. Dynamic quantitative photothermal monitoring of cell death of individual human red blood cells upon glucose depletion

    NASA Astrophysics Data System (ADS)

    Vasudevan, Srivathsan; Chen, George Chung Kit; Andika, Marta; Agarwal, Shuchi; Chen, Peng; Olivo, Malini

    2010-09-01

    Red blood cells (RBCs) have been found to undergo ``programmed cell death,'' or eryptosis, and understanding this process can provide more information about apoptosis of nucleated cells. Photothermal (PT) response, a label-free photothermal noninvasive technique, is proposed as a tool to monitor the cell death process of living human RBCs upon glucose depletion. Since the physiological status of the dying cells is highly sensitive to photothermal parameters (e.g., thermal diffusivity, absorption, etc.), we applied linear PT response to continuously monitor the death mechanism of RBC when depleted of glucose. The kinetics of the assay where the cell's PT response transforms from linear to nonlinear regime is reported. In addition, quantitative monitoring was performed by extracting the relevant photothermal parameters from the PT response. Twofold increases in thermal diffusivity and size reduction were found in the linear PT response during cell death. Our results reveal that photothermal parameters change earlier than phosphatidylserine externalization (used for fluorescent studies), allowing us to detect the initial stage of eryptosis in a quantitative manner. Hence, the proposed tool, in addition to detection of eryptosis earlier than fluorescence, could also reveal physiological status of the cells through quantitative photothermal parameter extraction.

  4. B and T Lymphocyte Attenuator Down-regulation by HIV-1 Depends on Type I Interferon and Contributes to T-Cell Hyperactivation

    PubMed Central

    Zhang, Zheng; Xu, Xiangsheng; Lu, Jiyun; Zhang, Shuye; Gu, Lanlan; Fu, Junliang; Jin, Lei; Li, Haiying; Zhao, Min; Zhang, Jiyuan; Wu, Hao; Su, Lishan; Fu, Yang-Xin

    2011-01-01

    Background. Nonspecific T-cell hyperactivation is the main driving force for human immunodeficiency virus (HIV)–1 disease progression, but the reasons why the excess immune response is not properly shut off are poorly defined. Methods. Eighty-five HIV-1–infected individuals were enrolled to characterize B and T lymphocyte attenuator (BTLA) expression and function. Infection and blockade assays were used to dissect the factors that influenced BTLA signaling in vitro. Results. BTLA expression on overall CD4+ and CD8+ T cells was progressively decreased in HIV-1 infection, which was directly correlated with disease progression and CD4+ T-cell differentiation and activation. BTLA+CD4+ T cells from HIV-1–infected patients also displayed an altered immune status, which was indicated by reduced expression of naive markers but increased activation and exhaustion markers. Cross-linking of BTLA can substantially decrease CD4+ T-cell activation in vitro. This responsiveness of CD4+ T cells to BTLA-mediated inhibitory signaling was further found to be impaired in HIV-1–infected patients. Furthermore, HIV-1 NL4-3 down-regulated BTLA expression on CD4+ T cells dependent on plasmacytoid dendritic cell (pDC)-derived interferon (IFN)-α. Blockade of IFN-α or depletion of pDCs prevents HIV-1-induced BTLA down-regulation. Conclusions. HIV-1 infection potentially impairs BTLA-mediated signaling dependent on pDC-derived IFN-α, which may contribute to broad T-cell hyperactivation induced by chronic HIV-1 infection. PMID:21592997

  5. Haploidentical transplant for myelodysplastic syndrome: registry-based comparison with identical sibling transplant.

    PubMed

    Wang, Y; Wang, H-X; Lai, Y-R; Sun, Z-M; Wu, D-P; Jiang, M; Liu, D-H; Xu, K-L; Liu, Q-F; Liu, L; Wang, J-B; Gao, F; Ou-Yang, J; Gao, S-J; Xu, L-P; Huang, X-J

    2016-10-01

    Encouraging results from a small sample of patients with myelodysplastic syndrome (MDS) undergoing haploidentical donor (HID) hematopoietic stem cell transplantation (HSCT) must be extended. Furthermore, an algorithm derived from a comparison of the outcomes of HID and identical-sibling donor (ISD) HSCT must be established. Therefore, the outcomes of 454 MDS patients who underwent HSCT from HIDs (n=226) or ISDs (n=228) between 2003 and 2013 that were reported to the Chinese Bone Marrow Transplantation Registry were analyzed. Among the 3/6 HID (n=136), 4-5/6 HID (n=90) and ISD patient groups, the 4-year adjusted cumulative incidences of non-relapse mortality were 34, 29 and 16%, respectively (overall P=0.004), and of relapse were 6, 7 and 10%, respectively (overall P=0.36). The 4-year adjusted probabilities of overall survival were 58, 63 and 73%, respectively (overall P=0.07), and of relapse-free-survival were 58, 63 and 71%, respectively (overall P=0.14); pairwise comparison showed that the difference was only statistically significant in the 3/6 HID vs ISD pair. The data suggest that ISDs remain the best donor source for MDS patients while HIDs (perhaps 4-5/6 HID in particular) could be a valid alternative when an ISD is not available; human leukocyte antigen disparity had no effect on survival among the HID patients.

  6. Increased T follicular helper cells and germinal center B cells are required for cGVHD and bronchiolitis obliterans

    PubMed Central

    Flynn, Ryan; Du, Jing; Veenstra, Rachelle G.; Reichenbach, Dawn K.; Panoskaltsis-Mortari, Angela; Taylor, Patricia A.; Freeman, Gordon J.; Serody, Jonathan S.; Murphy, William J.; Munn, David H.; Sarantopoulos, Stefanie; Luznik, Leo; Maillard, Ivan; Koreth, John; Cutler, Corey; Soiffer, Robert J.; Antin, Joseph H.; Ritz, Jerome; Dubovsky, Jason A.; Byrd, John C.; MacDonald, Kelli P.; Hill, Geoff R.; Blazar, Bruce R.

    2014-01-01

    Chronic graft-versus-host disease (cGVHD) is a leading cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation. Having shown that germinal center (GC) formation and immunoglobulin deposition are required for multiorgan system cGVHD and associated bronchiolitis obliterans syndrome (BOS) in a murine model, we hypothesized that T follicular helper (Tfh) cells are necessary for cGVHD by supporting GC formation and maintenance. We show that increased frequency of Tfh cells correlated with increased GC B cells, cGVHD, and BOS. Although administering a highly depletionary anti-CD20 monoclonal antibody (mAb) to mice with established cGVHD resulted in peripheral B-cell depletion, B cells remained in the lung, and BOS was not reversed. BOS could be treated by eliminating production of interleukin-21 (IL-21) by donor T cells or IL-21 receptor (IL-21R) signaling of donor B cells. Development of BOS was dependent upon T cells expressing the chemokine receptor CXCR5 to facilitate T-cell trafficking to secondary lymphoid organ follicles. Blocking mAbs for IL-21/IL-21R, inducible T-cell costimulator (ICOS)/ICOS ligand, and CD40L/CD40 hindered GC formation and cGVHD. These data provide novel insights into cGVHD pathogenesis, indicate a role for Tfh cells in these processes, and suggest a new line of therapy using mAbs targeting Tfh cells to reverse cGVHD. PMID:24820310

  7. Serum depletion induces changes in protein expression in the trophoblast-derived cell line HTR-8/SVneo.

    PubMed

    Novoa-Herran, Susana; Umaña-Perez, Adriana; Canals, Francesc; Sanchez-Gomez, Myriam

    2016-01-01

    How nutrition and growth factor restriction due to serum depletion affect trophoblast function remains poorly understood. We performed a proteomic differential study of the effects of serum depletion on a first trimester human immortalized trophoblast cell line. The viability of HTR-8/SVneo trophoblast cells in culture with 0, 0.5 and 10 % fetal bovine serum (FBS) were assayed via MTT at 24, 48 and 64 h. A comparative proteomic analysis of the cells grown with those FBS levels for 24 h was performed using two-dimensional electrophoresis (2DE), followed by mass spectrometry for protein spot identification, and a database search and bioinformatics analysis of the expressed proteins. Differential spots were identified using the Kolmogorov-Smirnov test ( n  = 3, significance level 0.10, D > 0.642) and/or ANOVA ( n  = 3, p  < 0.05). The results showed that low serum doses or serum depletion differentially affect cell growth and protein expression. Differential expression was seen in 25 % of the protein spots grown with 0.5 % FBS and in 84 % of those grown with 0 % FBS, using 10 % serum as the physiological control. In 0.5 % FBS, this difference was related with biological processes typically affected by the serum, such as cell cycle, regulation of apoptosis and proliferation. In addition to these changes, in the serum-depleted proteome we observed downregulation of keratin 8, and upregulation of vimentin, the glycolytic enzymes enolase and pyruvate kinase (PKM2) and tumor progression-related inosine-5'-monophosphate dehydrogenase 2 (IMPDH2) enzyme. The proteins regulated by total serum depletion, but not affected by growth in 0.5 % serum, are members of the glycolytic and nucleotide metabolic pathways and the epithelial-to-mesenchymal transition (EMT), suggesting an adaptive switch characteristic of malignant cells. This comparative proteomic analysis and the identified proteins are the first evidence of a protein expression response to serum

  8. Brain Ischemia Induces Diversified Neuroantigen-Specific T-Cell Responses That Exacerbate Brain Injury.

    PubMed

    Jin, Wei-Na; Gonzales, Rayna; Feng, Yan; Wood, Kristofer; Chai, Zhi; Dong, Jing-Fei; La Cava, Antonio; Shi, Fu-Dong; Liu, Qiang

    2018-06-01

    Autoimmune responses can occur when antigens from the central nervous system are presented to lymphocytes in the periphery or central nervous system in several neurological diseases. However, whether autoimmune responses emerge after brain ischemia and their impact on clinical outcomes remains controversial. We hypothesized that brain ischemia facilitates the genesis of autoimmunity and aggravates ischemic brain injury. Using a mouse strain that harbors a transgenic T-cell receptor to a central nervous system antigen, MOG 35-55 (myelin oligodendrocyte glycoprotein) epitope (2D2), we determined the anatomic location and involvement of antigen-presenting cells in the development of T-cell reactivity after brain ischemia and how T-cell reactivity impacts stroke outcome. Transient middle cerebral artery occlusion and photothrombotic stroke models were used in this study. We also quantified the presence and status of T cells from brain slices of ischemic patients. By coupling transfer of labeled MOG 35-55 -specific (2D2) T cells with tetramer tracking, we show an expansion in reactivity of 2D2 T cells to MOG 91-108 and MOG 103-125 in transient middle cerebral artery occlusion and photothrombotic stroke models. This reactivity and T-cell activation first occur locally in the brain after ischemia. Also, microglia act as antigen-presenting cells that effectively present MOG antigens, and depletion of microglia ablates expansion of 2D2 reactive T cells. Notably, the adoptive transfer of neuroantigen-experienced 2D2 T cells exacerbates Th1/Th17 responses and brain injury. Finally, T-cell activation and MOG-specific T cells are present in the brain of patients with ischemic stroke. Our findings suggest that brain ischemia activates and diversifies T-cell responses locally, which exacerbates ischemic brain injury. © 2018 The Authors.

  9. MTOR ACTIVATION TRIGGERS IL-4 PRODUCTION AND NECROTIC DEATH OF DOUBLE-NEGATIVE T CELLS IN PATIENTS WITH SYSTEMIC LUPUS ERYHTHEMATOSUS

    PubMed Central

    Lai, Zhi-Wei; Borsuk, Rebecca; Shadakshari, Ashwini; Yu, Jianghong; Dawood, Maha; Garcia, Ricardo; Francis, Lisa; Tily, Hajra; Bartos, Adam; Faraone, Stephen V.; Phillips, Paul; Perl, Andras

    2013-01-01

    The mechanistic target of rapamycin (mTOR) is recognized as a sensor of mitochondrial dysfunction and effector of T-cell lineage development, however, its role in autoimmunity, including systemic lupus erythematosus, remains unclear. Here, we prospectively evaluated mitochondrial dysfunction and mTOR activation in PBL relative to SLE disease activity index (SLEDAI) during 274 visits of 59 patients and 54 matched healthy subjects. Partial least square-discriminant analysis identified 15 of 212 parameters that accounted for 70.2% of the total variance and discriminated lupus and control samples (p<0.0005); increased mitochondrial mass of CD3+/CD4−/CD8− double-negative (DN) T cells (p=1.1×10−22) and FoxP3 depletion in CD4+/CD25+ T cells were top contributors (p=6.7×10−7). Prominent necrosis and mTOR activation were noted in DN T cells during 15 visits characterized by flares (SLEDAI increase ≥4) relative to 61 visits of remission (SLEDAI decrease ≥4). mTOR activation in DN T cells was also noted at pre-flare visits of SLE patients relative to those of stable disease or healthy controls. DN lupus T cells showed increased production of IL-4, which correlated with depletion of CD25+/CD19+B cells. Rapamycin treatment in vivo blocked the IL-4 production and necrosis of DN T cells, increased the expression of FoxP3 in CD25+/CD4+T cells, and expanded CD25+/CD19+ B cells. These results identify mTOR activation to be a trigger of IL-4 production and necrotic death of DN T cells in patients with SLE. PMID:23913957

  10. Nasopharyngeal infection by Streptococcus pyogenes requires superantigen-responsive Vβ-specific T cells

    PubMed Central

    Zeppa, Joseph J.; Kasper, Katherine J.; Mohorovic, Ivor; Mazzuca, Delfina M.

    2017-01-01

    The globally prominent pathogen Streptococcus pyogenes secretes potent immunomodulatory proteins known as superantigens (SAgs), which engage lateral surfaces of major histocompatibility class II molecules and T-cell receptor (TCR) β-chain variable domains (Vβs). These interactions result in the activation of numerous Vβ-specific T cells, which is the defining activity of a SAg. Although streptococcal SAgs are known virulence factors in scarlet fever and toxic shock syndrome, mechanisms by how SAgs contribute to the life cycle of S. pyogenes remain poorly understood. Herein, we demonstrate that passive immunization against the Vβ8-targeting SAg streptococcal pyrogenic exotoxin A (SpeA), or active immunization with either wild-type or a nonfunctional SpeA mutant, protects mice from nasopharyngeal infection; however, only passive immunization, or vaccination with inactive SpeA, resulted in high-titer SpeA-specific antibodies in vivo. Mice vaccinated with wild-type SpeA rendered Vβ8+ T cells poorly responsive, which prevented infection. This phenotype was reproduced with staphylococcal enterotoxin B, a heterologous SAg that also targets Vβ8+ T cells, and rendered mice resistant to infection. Furthermore, antibody-mediated depletion of T cells prevented nasopharyngeal infection by S. pyogenes, but not by Streptococcus pneumoniae, a bacterium that does not produce SAgs. Remarkably, these observations suggest that S. pyogenes uses SAgs to manipulate Vβ-specific T cells to establish nasopharyngeal infection. PMID:28794279

  11. Long-lived CD8+ T cell responses following Crimean-Congo haemorrhagic fever virus infection

    PubMed Central

    Goedhals, Dominique; Paweska, Janusz T.

    2017-01-01

    Crimean-Congo haemorrhagic fever virus (CCHFV) is a member of the Orthonairovirus genus of the Nairoviridae family and is associated with haemorrhagic fever in humans. Although T lymphocyte responses are known to play a role in protection from and clearance of viral infections, specific T cell epitopes have yet to be identified for CCHFV following infection. A panel of overlapping peptides covering the CCHFV nucleoprotein and the structural glycoproteins, GN and GC, were screened by ELISpot assay to detect interferon gamma (IFN-γ) production in vitro by peripheral blood mononuclear cells from eleven survivors with previous laboratory confirmed CCHFV infection. Reactive peptides were located predominantly on the nucleoprotein, with only one survivor reacting to two peptides from the glycoprotein GC. No single epitope was immunodominant, however all but one survivor showed reactivity to at least one T cell epitope. The responses were present at high frequency and detectable several years after the acute infection despite the absence of continued antigenic stimulation. T cell depletion studies confirmed that IFN-γ production as detected using the ELISpot assay was mediated chiefly by CD8+ T cells. This is the first description of CD8+ T cell epitopic regions for CCHFV and provides confirmation of long-lived T cell responses in survivors of CCHFV infection. PMID:29261651

  12. Oral dendritic cells mediate antigen-specific tolerance by stimulating TH1 and regulatory CD4+ T cells.

    PubMed

    Mascarell, Laurent; Lombardi, Vincent; Louise, Anne; Saint-Lu, Nathalie; Chabre, Henri; Moussu, Hélène; Betbeder, Didier; Balazuc, Anne-Marie; Van Overtvelt, Laurence; Moingeon, Philippe

    2008-09-01

    A detailed characterization of oral antigen-presenting cells is critical to improve second-generation sublingual allergy vaccines. To characterize oral dendritic cells (DCs) within lingual and buccal tissues from BALB/c mice with respect to their surface phenotype, distribution, and capacity to polarize CD4(+) T-cell responses. In situ analysis of oral DCs was performed by immunohistology. Purified DCs were tested in vitro for their capacity to capture, process, and present the ovalbumin antigen to naive CD4(+) T cells. In vivo priming of ovalbumin-specific T cells adoptively transferred to BALB/c mice was analyzed by cytofluorometry in cervical lymph nodes after sublingual administration of mucoadhesive ovalbumin. Three subsets of oral DCs with a distinct tissue distribution were identified: (1) a minor subset of CD207(+) Langerhans cells located in the mucosa itself, (2) a major subpopulation of CD11b(+)CD11c(-) and CD11b(+)CD11c(+) myeloid DCs at the mucosal/submucosal interface, and (3) B220(+)120G8(+) plasmacytoid DCs found in submucosal tissues. Purified myeloid and plasmacytoid oral DCs capture and process the antigen efficiently and are programmed to elicit IFN-gamma and/or IL-10 production together with a suppressive function in naive CD4(+) T cells. Targeting the ovalbumin antigen to oral DCs in vivo by using mucoadhesive particles establishes tolerance in the absence of cell depletion through the stimulation of IFN-gamma and IL-10-producing CD4(+) regulatory T cells in cervical lymph nodes. The oral immune system is composed of various subsets of tolerogenic DCs organized in a compartmentalized manner and programmed to induce T(H)1/regulatory T-cell responses.

  13. Circulating gamma delta T cells are activated and depleted during progression of high-grade gliomas: Implications for gamma delta T cell therapy of GBM

    USDA-ARS?s Scientific Manuscript database

    Glioblastoma multiforme (GBM) remains frustratingly impervious to any existing therapy. We have previously shown that GBM is sensitive to recognition and lysis by ex vivo activated gamma delta T cells, a minor subset of lymphocytes that innately recognize autologous stress-associated target antigens...

  14. Prenatal tolerance induction: relationship between cell dose, marrow T-cells, chimerism, and tolerance.

    PubMed

    Chen, Jeng-Chang; Chang, Ming-Ling; Huang, Shiu-Feng; Chang, Pei-Yeh; Muench, Marcus O; Fu, Ren-Huei; Ou, Liang-Shiou; Kuo, Ming-Ling

    2008-01-01

    It was reported that the dose of self-antigens can determine the consequence of deletional tolerance and donor T cells are critical for tolerance induction in mixed chimeras. This study aimed at assessing the effect of cell doses and marrow T cells on engraftment and tolerance induction after prenatal bone marrow transplantation. Intraperitoneal cell transplantation was performed in FVB/N (H-2K(q)) mice at gestational day 14 with escalating doses of adult C57BL/6 (H-2K(b)) marrows. Peripheral chimerism was examined postnatally by flow cytometry and tolerance was tested by skin transplantation. Transplantation of light-density marrow cells showed a dose response. High-level chimerism emerged with a threshold dose of 5.0 x 10(6) and host leukocytes could be nearly replaced at a dose of 7.5-10.0 x 10(6). High-dose transplants conferred a steady long-lasting donor-specific tolerance but were accompanied by >50% incidence of graft-versus-host disease. Depletion of marrow T cells lessened graft-versus-host disease to the detriment of engraftment. With low-level chimerism, tolerance was a graded phenomenon dependent upon the level of chimerism. Durable chimerism within 6 months required a threshold of > or = 2% chimerism at 1 month of age and predicted a 50% chance of long-term tolerance, whereas transient chimerism (<2%) only caused hyporesponsiveness to the donor. Tolerance induction did not succeed without peripheral chimerism even if a large amount of injected donor cells persisted in the peritoneum. Neither did an increase in cell doses or donor T-cell contents benefit skin graft survivals unless it had substantially improved peripheral chimerism. Thus, peripheral chimerism level can be a simple and straightforward test to predict the degree of prenatal immune tolerance.

  15. Attrition of memory CD8 T cells during sepsis requires LFA-1.

    PubMed

    Serbanescu, Mara A; Ramonell, Kimberly M; Hadley, Annette; Margoles, Lindsay M; Mittal, Rohit; Lyons, John D; Liang, Zhe; Coopersmith, Craig M; Ford, Mandy L; McConnell, Kevin W

    2016-11-01

    CD8 T cell loss and dysfunction have been implicated in the increased susceptibility to opportunistic infections during the later immunosuppressive phase of sepsis, but CD8 T cell activation and attrition in early sepsis remain incompletely understood. With the use of a CLP model, we assessed CD8 T cell activation at 5 consecutive time points and found that activation after sepsis results in a distinct phenotype (CD69 + CD25 int CD62L HI ) independent of cognate antigen recognition and TCR engagement and likely through bystander-mediated cytokine effects. Additionally, we observed that sepsis concurrently results in the preferential depletion of a subset of memory-phenotype CD8 T cells that remain "unactivated" (i.e., fail to up-regulate activation markers) by apoptosis. Unactivated CD44 HI OT-I cells were spared from sepsis-induced attrition, as were memory-phenotype CD8 T cells of mice treated with anti-LFA-1 mAb, 1 h after CLP. Perhaps most importantly, we demonstrate that attrition of memory phenotype cells may have a pathologic significance, as elevated IL-6 levels were associated with decreased numbers of memory-phenotype CD8 T cells in septic mice, and preservation of this subset after administration of anti-LFA-1 mAb conferred improved survival at 7 d. Taken together, these data identify potentially modifiable responses of memory-phenotype CD8 T cells in early sepsis and may be particularly important in the application of immunomodulatory therapies in sepsis. © Society for Leukocyte Biology.

  16. Attrition of memory CD8 T cells during sepsis requires LFA-1

    PubMed Central

    Serbanescu, Mara A.; Ramonell, Kimberly M.; Hadley, Annette; Margoles, Lindsay M.; Mittal, Rohit; Lyons, John D.; Liang, Zhe; Coopersmith, Craig M.; Ford, Mandy L.; McConnell, Kevin W.

    2016-01-01

    CD8 T cell loss and dysfunction have been implicated in the increased susceptibility to opportunistic infections during the later immunosuppressive phase of sepsis, but CD8 T cell activation and attrition in early sepsis remain incompletely understood. With the use of a CLP model, we assessed CD8 T cell activation at 5 consecutive time points and found that activation after sepsis results in a distinct phenotype (CD69+CD25intCD62LHI) independent of cognate antigen recognition and TCR engagement and likely through bystander-mediated cytokine effects. Additionally, we observed that sepsis concurrently results in the preferential depletion of a subset of memory-phenotype CD8 T cells that remain “unactivated” (i.e., fail to up-regulate activation markers) by apoptosis. Unactivated CD44HI OT-I cells were spared from sepsis-induced attrition, as were memory-phenotype CD8 T cells of mice treated with anti-LFA-1 mAb, 1 h after CLP. Perhaps most importantly, we demonstrate that attrition of memory phenotype cells may have a pathologic significance, as elevated IL-6 levels were associated with decreased numbers of memory-phenotype CD8 T cells in septic mice, and preservation of this subset after administration of anti-LFA-1 mAb conferred improved survival at 7 d. Taken together, these data identify potentially modifiable responses of memory-phenotype CD8 T cells in early sepsis and may be particularly important in the application of immunomodulatory therapies in sepsis. PMID:27286793

  17. Requirement of T-lymphokine-activated killer cell-originated protein kinase for TRAIL resistance of human HeLa cervical cancer cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kwon, Hyeok-Ran; Lee, Ki Won; Dong, Zigang

    2010-01-01

    T-lymphokine-activated killer cell-originated protein kinase (TOPK) appears to be highly expressed in various cancer cells and to play an important role in maintaining proliferation of cancer cells. However, the underlying mechanism by which TOPK regulates growth of cancer cells remains elusive. Here we report that upregulated endogenous TOPK augments resistance of cancer cells to apoptosis induced by tumor necrosis factor-related apoptosis inducing ligand (TRAIL). Stable knocking down of TOPK markedly increased TRAIL-mediated apoptosis of human HeLa cervical cancer cells, as compared with control cells. Caspase 8 or caspase 3 activities in response to TRAIL were greatly incremented in TOPK-depleted cells.more » Ablation of TOPK negatively regulated TRAIL-mediated NF-{kappa}B activity. Furthermore, expression of NF-{kappa}B-dependent genes, FLICE-inhibitory protein (FLIP), inhibitor of apoptosis protein 1 (c-IAP1), or X-linked inhibitor of apoptosis protein (XIAP) was reduced in TOPK-depleted cells. Collectively, these findings demonstrated that TOPK contributed to TRAIL resistance of cancer cells via NF-{kappa}B activity, suggesting that TOPK might be a potential molecular target for successful cancer therapy using TRAIL.« less

  18. Regulatory T cells are recruited in the infarcted mouse myocardium and may modulate fibroblast phenotype and function

    PubMed Central

    Saxena, Amit; Dobaczewski, Marcin; Rai, Vikrant; Haque, Zaffar; Chen, Wei; Li, Na

    2014-01-01

    Regulatory T cells (Tregs) play a pivotal role in suppressing immune responses regulating behavior and gene expression in effector T cells, macrophages, and dendritic cells. Tregs infiltrate the infarcted myocardium; however, their role the inflammatory and reparative response after myocardial infarction remains poorly understood. We used FoxP3EGFP reporter mice to study Treg trafficking in the infarcted heart and examined the effects of Treg depletion on postinfarction remodeling using an anti-CD25 antibody. Moreover, we investigated the in vitro effects of Tregs on cardiac fibroblast phenotype and function. Low numbers of Tregs infiltrated the infarcted myocardium after 24–72 h of reperfusion. Treg depletion had no significant effects on cardiac dysfunction and scar size after reperfused myocardial infarction but accelerated ventricular dilation and accentuated apical remodeling. Enhanced myocardial dilation in Treg-depleted animals was associated with increased expression of chemokine (C-C motif) ligand 2 and accentuated macrophage infiltration. In vitro, Tregs modulated the cardiac fibroblast phenotype, reducing expression of α-smooth muscle actin, decreasing expression of matrix metalloproteinase-3, and attenuating contraction of fibroblast-populated collagen pads. Our findings suggest that endogenous Tregs have modest effects on the inflammatory and reparative response after myocardial infarction. However, the anti-inflammatory and matrix-preserving properties of Tregs may suggest a role for Treg-based cell therapy in the attenuation of adverse postinfarction remodeling. PMID:25128167

  19. Distinct Mechanisms of Ferritin Delivery to Lysosomes in Iron-Depleted and Iron-Replete Cells

    PubMed Central

    Asano, Takeshi; Komatsu, Masaaki; Yamaguchi-Iwai, Yuko; Ishikawa, Fuyuki; Mizushima, Noboru; Iwai, Kazuhiro

    2011-01-01

    Ferritin is a cytosolic protein that stores excess iron, thereby protecting cells from iron toxicity. Ferritin-stored iron is believed to be utilized when cells become iron deficient; however, the mechanisms underlying the extraction of iron from ferritin have yet to be fully elucidated. Here, we demonstrate that ferritin is degraded in the lysosome under iron-depleted conditions and that the acidic environment of the lysosome is crucial for iron extraction from ferritin and utilization by cells. Ferritin was targeted for degradation in the lysosome even under iron-replete conditions in primary cells; however, the mechanisms underlying lysosomal targeting of ferritin were distinct under depleted and replete conditions. In iron-depleted cells, ferritin was targeted to the lysosome via a mechanism that involved autophagy. In contrast, lysosomal targeting of ferritin in iron-replete cells did not involve autophagy. The autophagy-independent pathway of ferritin delivery to lysosomes was deficient in several cancer-derived cells, and cancer-derived cell lines are more resistant to iron toxicity than primary cells. Collectively, these results suggest that ferritin trafficking may be differentially regulated by cell type and that loss of ferritin delivery to the lysosome under iron-replete conditions may be related to oncogenic cellular transformation. PMID:21444722

  20. Natural Killer Dendritic Cells Enhance Immune Responses Elicited by α -Galactosylceramide-Stimulated Natural Killer T Cells.

    PubMed

    Lee, Sung Won; Park, Hyun Jung; Kim, Nayoung; Hong, Seokmann

    2013-01-01

    Natural killer dendritic cells (NKDCs) possess potent anti-tumor activity, but the cellular effect of NKDC interactions with other innate immune cells is unclear. In this study, we demonstrate that the interaction of NKDCs and natural killer T (NKT) cells is required for the anti-tumor immune responses that are elicited by α -galactosylceramide ( α -GC) in mice. The rapid and strong expression of interferon- γ by NKDCs after α -GC stimulation was dependent on NKT cells. Various NK and DC molecular markers and cytotoxic molecules were up-regulated following α -GC administration. This up-regulation could improve NKDC presentation of tumor antigens and increase cytotoxicity against tumor cells. NKDCs were required for the stimulation of DCs, NK cells, and NKT cells. The strong anti-tumor immune responses elicited by α -GC may be due to the down-regulation of regulatory T cells. Furthermore, the depletion of NKDCs dampened the tumor clearance mediated by α -GC-stimulated NKT cells in vivo. Taken together, these results indicate that complex interactions of innate immune cells might be required to achieve optimal anti-tumor immune responses during the early stages of tumorigenesis.

  1. CD4+ CD25high Foxp3+ regulatory T cells downregulate human Vδ2+ T-lymphocyte function triggered by anti-CD3 or phosphoantigen

    PubMed Central

    Mahan, C Scott; Thomas, Jeremy J; Boom, W Henry; Rojas, Roxana E

    2009-01-01

    Vδ2+ T cells, the major circulating T-cell receptor-γδ-positive (TCR-γδ+) T-cell subset in healthy adults, are involved in immunity against many microbial pathogens including Mycobacterium tuberculosis. Vδ2+ T cells recognize small phosphorylated metabolites (phosphoantigens), expand in response to whole M. tuberculosis bacilli, and complement the protective functions of CD4+ T cells. CD4+ CD25high Foxp3+ T cells (Tregs) comprise 5–10% of circulating T cells and are increased in patients with active tuberculosis (TB). We investigated whether, in addition to their known role in suppressing TCR-αβ+ lymphocytes, Tregs suppress Vδ2+ T-cell function. We found that depletion of Tregs from peripheral blood mononuclear cells increased Vδ2+ T-cell expansion in response to M. tuberculosis (H37Ra) in tuberculin-skin-test-positive donors. We developed a suppression assay with fluorescence-activated cell sorting-purified Tregs and Vδ2+ T cells by coincubating the two cell types at a 1 : 1 ratio. The Tregs partially suppressed interferon-γ secretion by Vδ2+ T cells in response to anti-CD3 monoclonal antibody plus interleukin-2 (IL-2). In addition, Tregs downregulated the Vδ2+ T-cell interferon-γ responses induced by phosphoantigen (BrHPP) and IL-2. Under the latter conditions there was no TCR stimulus for Tregs and therefore IL-2 probably triggered suppressor activity. Addition of purified protein derivative (PPD) increased the suppression of Vδ2+ T cells, suggesting that PPD activated antigen-specific Tregs. Our study provides evidence that Tregs suppress both anti-CD3 and antigen-driven Vδ2+ T-cell activation. Antigen-specific Tregs may therefore contribute to the Vδ2+ T-cell functional deficiencies observed in TB. PMID:19019089

  2. Na+ influx via Orai1 inhibits intracellular ATP-induced mTORC2 signaling to disrupt CD4 T cell gene expression and differentiation.

    PubMed

    Miao, Yong; Bhushan, Jaya; Dani, Adish; Vig, Monika

    2017-05-11

    T cell effector functions require sustained calcium influx. However, the signaling and phenotypic consequences of non-specific sodium permeation via calcium channels remain unknown. α-SNAP is a crucial component of Orai1 channels, and its depletion disrupts the functional assembly of Orai1 multimers. Here we show that α-SNAP hypomorph, hydrocephalus with hopping gait, Napa hyh/hyh mice harbor significant defects in CD4 T cell gene expression and Foxp3 regulatory T cell (Treg) differentiation. Mechanistically, TCR stimulation induced rapid sodium influx in Napa hyh/hyh CD4 T cells, which reduced intracellular ATP, [ATP] i . Depletion of [ATP] i inhibited mTORC2 dependent NFκB activation in Napa hyh/hyh cells but ablation of Orai1 restored it. Remarkably, TCR stimulation in the presence of monensin phenocopied the defects in Napa hyh/hyh signaling and Treg differentiation, but not IL-2 expression. Thus, non-specific sodium influx via bonafide calcium channels disrupts unexpected signaling nodes and may provide mechanistic insights into some divergent phenotypes associated with Orai1 function.

  3. Na+ influx via Orai1 inhibits intracellular ATP-induced mTORC2 signaling to disrupt CD4 T cell gene expression and differentiation

    PubMed Central

    Miao, Yong; Bhushan, Jaya; Dani, Adish; Vig, Monika

    2017-01-01

    T cell effector functions require sustained calcium influx. However, the signaling and phenotypic consequences of non-specific sodium permeation via calcium channels remain unknown. α-SNAP is a crucial component of Orai1 channels, and its depletion disrupts the functional assembly of Orai1 multimers. Here we show that α-SNAP hypomorph, hydrocephalus with hopping gait, Napahyh/hyh mice harbor significant defects in CD4 T cell gene expression and Foxp3 regulatory T cell (Treg) differentiation. Mechanistically, TCR stimulation induced rapid sodium influx in Napahyh/hyh CD4 T cells, which reduced intracellular ATP, [ATP]i. Depletion of [ATP]i inhibited mTORC2 dependent NFκB activation in Napahyh/hyh cells but ablation of Orai1 restored it. Remarkably, TCR stimulation in the presence of monensin phenocopied the defects in Napahyh/hyh signaling and Treg differentiation, but not IL-2 expression. Thus, non-specific sodium influx via bonafide calcium channels disrupts unexpected signaling nodes and may provide mechanistic insights into some divergent phenotypes associated with Orai1 function. DOI: http://dx.doi.org/10.7554/eLife.25155.001 PMID:28492364

  4. Naive T-cell receptor transgenic T cells help memory B cells produce antibody

    PubMed Central

    Duffy, Darragh; Yang, Chun-Ping; Heath, Andrew; Garside, Paul; Bell, Eric B

    2006-01-01

    Injection of the same antigen following primary immunization induces a classic secondary response characterized by a large quantity of high-affinity antibody of an immunoglobulin G class produced more rapidly than in the initial response – the products of memory B cells are qualitatively distinct from that of the original naive B lymphocytes. Very little is known of the help provided by the CD4 T cells that stimulate memory B cells. Using antigen-specific T-cell receptor transgenic CD4 T cells (DO11.10) as a source of help, we found that naive transgenic T cells stimulated memory B cells almost as well (in terms of quantity and speed) as transgenic T cells that had been recently primed. There was a direct correlation between serum antibody levels and the number of naive transgenic T cells transferred. Using T cells from transgenic interleukin-2-deficient mice we showed that interleukin-2 was not required for a secondary response, although it was necessary for a primary response. The results suggested that the signals delivered by CD4 T cells and required by memory B cells for their activation were common to both antigen-primed and naive CD4 T cells. PMID:17067314

  5. Targeting CD4+ T cells for the treatment of sarcoidosis: a promising strategy?

    PubMed Central

    Celada, Lindsay J; Drake, Wonder P

    2017-01-01

    Sarcoidois is an inflammatory disease of unknown origin characterized by the abnormal accumulation of noncaseating granulomas at sites of disease activity in multiple organs throughout the body with a predilection for the lungs. Because the exact trigger that leads to disease activity is still under investigation, current treatment options are contingent on the organ or organs affected. Corticosteroids are the therapy of choice, but antimalarials and TNF-α antagonists are also commonly prescribed. Recent findings provide evidence for the use of CD20 B-cell-depleting therapy as an alternative method of choice. However, because sarcoidosis is predominantly a T-helper cell-driven disorder, an overwhelming amount of compelling evidence exists for the use of CD4+ T-cell targeted therapy. PMID:25572480

  6. Visualizing the Rapid and Dynamic Elimination of Allogeneic T Cells in Secondary Lymphoid Organs.

    PubMed

    Kanda, Yasuhiro; Takeuchi, Arata; Ozawa, Madoka; Kurosawa, Yoichi; Kawamura, Toshihiko; Bogdanova, Dana; Iioka, Hidekazu; Kondo, Eisaku; Kitazawa, Yusuke; Ueta, Hisashi; Matsuno, Kenjiro; Kinashi, Tatsuo; Katakai, Tomoya

    2018-06-20

    Allogeneic organ transplants are rejected by the recipient immune system within several days or weeks. However, the rejection process of allogeneic T (allo-T) cells is poorly understood. In this study, using fluorescence-based monitoring and two-photon live imaging in mouse adoptive transfer system, we visualized the fate of allo-T cells in the in vivo environment and showed rapid elimination in secondary lymphoid organs (SLOs). Although i.v. transferred allo-T cells efficiently entered host SLOs, including lymph nodes and the spleen, ∼70% of the cells had disappeared within 24 h. At early time points, allo-T cells robustly migrated in the T cell area, whereas after 8 h, the numbers of arrested cells and cell fragments were dramatically elevated. Apoptotic breakdown of allo-T cells released a large amount of cell debris, which was efficiently phagocytosed and cleared by CD8 + dendritic cells. Rapid elimination of allo-T cells was also observed in nu/nu recipients. Depletion of NK cells abrogated allo-T cell reduction only in a specific combination of donor and recipient genetic backgrounds. In addition, F 1 hybrid transfer experiments showed that allo-T cell killing was independent of the missing-self signature typically recognized by NK cells. These suggest the presence of a unique and previously uncharacterized modality of allorecognition by the host immune system. Taken together, our findings reveal an extremely efficient and dynamic process of allogeneic lymphocyte elimination in SLOs, which could not be recapitulated in vitro and is distinct from the rejection of solid organ and bone marrow transplants. Copyright © 2018 by The American Association of Immunologists, Inc.

  7. 2B4-SAP signaling is required for the priming of naive CD8+ T cells by antigen-expressing B cells and B lymphoma cells

    PubMed Central

    2017-01-01

    ABSTRACT Mutations in SH2D1A gene that encodes SAP (SLAM-associated protein) result in X-linked lymphoproliferative disease (XLP), a rare primary immunodeficiency disease defined by exquisite sensitivity to the B-lymphotropic Epstein–Barr virus (EBV) and B cell lymphomas. However, the precise mechanism of how the loss of SAP function contributes to extreme vulnerability to EBV and the development of B cell lymphomas remains unclear. Here, we investigate the hypothesis that SAP is critical for CD8+ T cell immune surveillance of antigen (Ag)-expressing B cells or B lymphoma cells under conditions of defined T cell receptor (TCR) signaling. Sh2d1a−/− CD8+ T cells exhibited greatly diminished proliferation relative to wild type when Ag-presenting-B cells or -B lymphoma cells served as the primary Ag-presenting cell (APC). By contrast, Sh2d1a−/− CD8+ T cells responded equivalently to wild-type CD8+ T cells when B cell-depleted splenocytes, melanoma cells or breast carcinoma cells performed Ag presentation. Through application of signaling lymphocyte activation molecule (SLAM) family receptor blocking antibodies or SLAM family receptor-deficient CD8+ T cells and APCs, we found that CD48 engagement on the B cell surface by 2B4 is crucial for initiating SAP-dependent signaling required for the Ag-driven CD8+ T cell proliferation and differentiation. Altogether, a pivotal role for SAP in promoting the expansion and differentiation of B cell-primed viral-specific naive CD8+ T cells may explain the selective immune deficiency of XLP patients to EBV and B cell lymphomas. PMID:28344876

  8. 2B4-SAP signaling is required for the priming of naive CD8+ T cells by antigen-expressing B cells and B lymphoma cells.

    PubMed

    Huang, Yu-Hsuan; Tsai, Kevin; Tan, Sara Y; Kang, Sohyeong; Ford, Mandy L; Harder, Kenneth W; Priatel, John J

    2017-01-01

    Mutations in SH2D1A gene that encodes SAP (SLAM-associated protein) result in X-linked lymphoproliferative disease (XLP), a rare primary immunodeficiency disease defined by exquisite sensitivity to the B-lymphotropic Epstein-Barr virus (EBV) and B cell lymphomas. However, the precise mechanism of how the loss of SAP function contributes to extreme vulnerability to EBV and the development of B cell lymphomas remains unclear. Here, we investigate the hypothesis that SAP is critical for CD8 + T cell immune surveillance of antigen (Ag)-expressing B cells or B lymphoma cells under conditions of defined T cell receptor (TCR) signaling. Sh2d1a - / - CD8 + T cells exhibited greatly diminished proliferation relative to wild type when Ag-presenting-B cells or -B lymphoma cells served as the primary Ag-presenting cell (APC). By contrast, Sh2d1a - / - CD8 + T cells responded equivalently to wild-type CD8 + T cells when B cell-depleted splenocytes, melanoma cells or breast carcinoma cells performed Ag presentation. Through application of signaling lymphocyte activation molecule (SLAM) family receptor blocking antibodies or SLAM family receptor-deficient CD8 + T cells and APCs, we found that CD48 engagement on the B cell surface by 2B4 is crucial for initiating SAP-dependent signaling required for the Ag-driven CD8 + T cell proliferation and differentiation. Altogether, a pivotal role for SAP in promoting the expansion and differentiation of B cell-primed viral-specific naive CD8 + T cells may explain the selective immune deficiency of XLP patients to EBV and B cell lymphomas.

  9. Pb exposure attenuates hypersensitivity in vivo by increasing regulatory T cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fang, Liang; Zhao, Fang; Shen, Xuefeng

    Pb is a common environmental pollutant affecting various organs. Exposure of the immune system to Pb leads to immunosuppression or immunodysregulation. Although previous studies showed that Pb exposure can modulate the function of helper T cells, Pb immunotoxicity remains incompletely understood. In this study, we investigated the effect of Pb exposure on T cell development, and the underlying mechanism of Pb-induced suppression of the delayed-type hypersensitivity (DTH) response in vivo. Sprague–Dawley rats were exposed to 300 ppm Pb-acetate solution via the drinking water for six weeks, and we found that Pb exposure significantly increased Pb concentrations in the blood bymore » 4.2-fold (p < 0.05) as compared to those in the control rats. In Pb-exposed rats, the amount of thymic CD4{sup +}CD8{sup −} and peripheral CD4{sup +} T cells was significantly reduced, whereas, CD8{sup +} population was not affected. In contrast to conventional CD4{sup +} T cells, Foxp3{sup +} regulatory T cells (Tregs) were increased in both the thymus and peripheral lymphoid organs of Pb-exposed rats. In line with the increase of Tregs, the DTH response of Pb-exposed rats was markedly suppressed. Depletion of Tregs reversed the suppression of DTH response by Pb-exposed CD4{sup +} T cells in an adoptive transfer model, suggesting a critical role of the increased Tregs in suppressing the DTH response. Collectively, this study revealed that Pb-exposure may upregulate Tregs, thereby leading to immunosuppression. -- Highlights: ► Pb exposure impaired CD4{sup +} thymic T cell development. ► Peripheral T lymphocytes were reduced following Pb exposure. ► Pb exposure increases thymic and peripheral Treg cells in rats. ► Tregs played a critical role in Pb-exposure-induced immune suppression.« less

  10. Cell culture alters Ca2+ entry pathways activated by store-depletion or hypoxia in canine pulmonary arterial smooth muscle cells.

    PubMed

    Ng, Lih Chyuan; Kyle, Barry D; Lennox, Alison R; Shen, Xiao-Ming; Hatton, William J; Hume, Joseph R

    2008-01-01

    Previous studies have shown that, in acutely dispersed canine pulmonary artery smooth muscle cells (PASMCs), depletion of both functionally independent inositol 1,4,5-trisphosphate (IP(3))- and ryanodine-sensitive Ca(2+) stores activates capacitative Ca(2+) entry (CCE). The present study aimed to determine if cell culture modifies intracellular Ca(2+) stores and alters Ca(2+) entry pathways caused by store depletion and hypoxia in canine PASMCs. Intracellular Ca(2+) concentration ([Ca(2+)](i)) was measured in fura 2-loaded cells. Mn(2+) quench of fura 2 signal was performed to study divalent cation entry, and the effects of hypoxia were examined under oxygen tension of 15-18 mmHg. In acutely isolated PASMCs, depletion of IP(3)-sensitive Ca(2+) stores with cyclopiazonic acid (CPA) did not affect initial caffeine-induced intracellular Ca(2+) transients but abolished 5-HT-induced Ca(2+) transients. In contrast, CPA significantly reduced caffeine- and 5-HT-induced Ca(2+) transients in cultured PASMCs. In cultured PASMCs, store depletion or hypoxia caused a transient followed by a sustained rise in [Ca(2+)](i). The transient rise in [Ca(2+)](i) was partially inhibited by nifedipine, whereas the nifedipine-insensitive transient rise in [Ca(2+)](i) was inhibited by KB-R7943, a selective inhibitor of reverse mode Na(+)/Ca(2+) exchanger (NCX). The nifedipine-insensitive sustained rise in [Ca(2+)](i) was inhibited by SKF-96365, Ni(2+), La(3+), and Gd(3+). In addition, store depletion or hypoxia increased the rate of Mn(2+) quench of fura 2 fluorescence that was also inhibited by these blockers, exhibiting pharmacological properties characteristic of CCE. We conclude that cell culture of canine PASMCs reorganizes IP(3) and ryanodine receptors into a common intracellular Ca(2+) compartment, and depletion of this store or hypoxia activates voltage-operated Ca(2+) entry, reverse mode NCX, and CCE.

  11. Single-cell profiling of peanut-responsive T cells in patients with peanut allergy reveals heterogeneous effector TH2 subsets.

    PubMed

    Chiang, David; Chen, Xintong; Jones, Stacie M; Wood, Robert A; Sicherer, Scott H; Burks, A Wesley; Leung, Donald Y M; Agashe, Charuta; Grishin, Alexander; Dawson, Peter; Davidson, Wendy F; Newman, Leah; Sebra, Robert; Merad, Miriam; Sampson, Hugh A; Losic, Bojan; Berin, M Cecilia

    2018-06-01

    The contribution of phenotypic variation of peanut-specific T cells to clinical allergy or tolerance to peanut is not well understood. Our objective was to comprehensively phenotype peanut-specific T cells in the peripheral blood of subjects with and without peanut allergy (PA). We obtained samples from patients with PA, including a cohort undergoing baseline peanut challenges for an immunotherapy trial (Consortium of Food Allergy Research [CoFAR] 6). Subjects were confirmed as having PA, or if they passed a 1-g peanut challenge, they were termed high-threshold subjects. Healthy control (HC) subjects were also recruited. Peanut-responsive T cells were identified based on CD154 expression after 6 to 18 hours of stimulation with peanut extract. Cells were analyzed by using flow cytometry and single-cell RNA sequencing. Patients with PA had tissue- and follicle-homing peanut-responsive CD4 + T cells with a heterogeneous pattern of T H 2 differentiation, whereas control subjects had undetectable T-cell responses to peanut. The PA group had a delayed and IL-2-dependent upregulation of CD154 on cells expressing regulatory T (Treg) cell markers, which was absent in HC or high-threshold subjects. Depletion of Treg cells enhanced cytokine production in HC subjects and patients with PA in vitro, but cytokines associated with highly differentiated T H 2 cells were more resistant to Treg cell suppression in patients with PA. Analysis of gene expression by means of single-cell RNA sequencing identified T cells with highly correlated expression of IL4, IL5, IL9, IL13, and the IL-25 receptor IL17RB. These results demonstrate the presence of highly differentiated T H 2 cells producing T H 2-associated cytokines with functions beyond IgE class-switching in patients with PA. A multifunctional T H 2 response was more evident than a Treg cell deficit among peanut-responsive T cells. Copyright © 2018 American Academy of Allergy, Asthma & Immunology. All rights reserved.

  12. Engraftment for CD34 selected stem cell products is not compromised by cryopreservation.

    PubMed

    Reich-Slotky, Ronit; Bachegowda, Lohith S; Ancharski, Michael; Gergis, Usama; van Besien, Koen; Cushing, Melissa M

    2016-04-01

    The coinfusion of haploidentical CD34+ selected peripheral blood stem cell products with umbilical cord blood (UCB) provides early neutrophil recovery, long-term UCB engraftment, and a lower incidence of graft-versus-host disease; however, this complex transplant presents a scheduling challenge for both the cellular therapy laboratory and the clinical team. Cryopreservation of the haploidentical product can facilitate scheduling, but has been previously shown to be associated with infusion reactions and delayed platelet (PLT) engraftment in allogeneic hematopoietic progenitor cell transplant. To test whether cryopreservation of the CD34+ selected product compromises the graft, we compared neutrophil and PLT engraftment kinetics for patients receiving freshly infused or cryopreserved products. Seventy-two products collected from haploidentical related donors were CD34+ selected and infused in a combined transplant with UCB: 32 were cryopreserved before infusion and 40 were infused fresh. No adverse infusion events were reported in either group and there was no difference in neutrophil and PLT engraftment time between fresh and cryopreserved products. Cryopreservation of a CD34+-selected product can be safely used in a combined transplant with UCB and does not affect engraftment time. © 2015 AABB.

  13. Profiling calcium signals of in vitro polarized human effector CD4+ T cells.

    PubMed

    Kircher, Sarah; Merino-Wong, Maylin; Niemeyer, Barbara A; Alansary, Dalia

    2018-06-01

    Differentiation of naïve CD4 + T cells into effector subtypes with distinct cytokine profiles and physiological roles is a tightly regulated process, the imbalance of which can lead to an inadequate immune response or autoimmune disease. The crucial role of Ca 2+ signals, mainly mediated by the store operated Ca 2+ entry (SOCE) in shaping the immune response is well described. However, it is unclear if human effector CD4 + T cell subsets show differential Ca 2+ signatures in response to different stimulation methods. Herein, we provide optimized in vitro culture conditions for polarization of human CD4 + effector T cells and characterize their SOCE following both pharmacological store depletion and direct T-cell receptor (TCR) activation. Moreover, we measured whole cell Ca 2+ release activated Ca 2+ currents (I CRAC ) and investigated whether the observed differences correlate to the expression of CRAC genes. Our results show that Ca 2+ profiles of helper CD4 + Th1, Th2 and Th17 are distinct and in part shaped by the intensity of stimulation. Regulatory T cells (Treg) are unique being the subtype with the most prominent SOCE response. Analysis of in vivo differentiated Treg unraveled the role of differential expression of ORAI2 in fine-tuning signals in Treg vs. conventional CD4 + T cells. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

  14. Third-party CD4+ invariant natural killer T cells protect from murine GVHD lethality

    PubMed Central

    Schneidawind, Dominik; Baker, Jeanette; Pierini, Antonio; Buechele, Corina; Luong, Richard H.; Meyer, Everett H.

    2015-01-01

    Graft-versus-host disease (GVHD) is driven by extensive activation and proliferation of alloreactive donor T cells causing significant morbidity and mortality following allogeneic hematopoietic cell transplantation (HCT). Invariant natural killer T (iNKT) cells are a potent immunoregulatory T-cell subset in both humans and mice. Here, we explored the role of adoptively transferred third-party CD4+ iNKT cells for protection from lethal GVHD in a murine model of allogeneic HCT across major histocompatibility barriers. We found that low numbers of CD4+ iNKT cells from third-party mice resulted in a significant survival benefit with retained graft-versus-tumor effects. In vivo expansion of alloreactive T cells was diminished while displaying a T helper cell 2-biased phenotype. Notably, CD4+ iNKT cells from third-party mice were as protective as CD4+ iNKT cells from donor mice although third-party CD4+ iNKT cells were rejected early after allogeneic HCT. Adoptive transfer of third-party CD4+ iNKT cells resulted in a robust expansion of donor CD4+CD25+FoxP3+ regulatory T cells (Tregs) that were required for protection from lethal GVHD. However, in vivo depletion of myeloid-derived suppressor cells abrogated both Treg expansion and protection from lethal GVHD. Despite the fact that iNKT cells are a rare cell population, the almost unlimited third-party availability and feasibility of in vitro expansion provide the basis for clinical translation. PMID:25795920

  15. The Total Body Irradiation Schedule Affects Acute Leukemia Relapse After Matched T Cell–Depleted Hematopoietic Stem Cell Transplantation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aristei, Cynthia, E-mail: cynthia.aristei@unipg.it; Carotti, Alessandra; Palazzari, Elisa

    Purpose: We sought to determine whether the total body irradiation (TBI) schedule affected outcome in patients with acute leukemia in complete remission who received T cell–depleted allogeneic hematopoietic stem cell transplantation from HLA identical siblings. Methods and Materials: The study recruited 55 patients (median age, 48 years; age range, 20-66 years; 30 men and 25 women; 34 with acute myeloid leukemia and 21 with acute lymphoid leukemia). Hyperfractionated TBI (HTBI) (1.2 Gy thrice daily for 4 days [for a total dose of 14.4 Gy] from day −12 to day −9) was administered to 29 patients. Single-dose TBI (STBI) (8 Gy, at a median dose rate of 10.7 cGy/minmore » on day −9) was given to 26 patients. Results: All patients achieved primary, sustained engraftment with full donor-type chimerism. At 10 years, the overall cumulative incidence of transplant-related mortality was 11% (SE, ±0.1%). It was 7% (SE, ±0.2%) after HTBI and 15% (SE, ±0.5%) after STBI (P=.3). The overall cumulative incidence of relapse was 33% (SE, ±0.5). It was 13% (SE, ±0.5%) after HTBI and 46% (SE, ±1%) after STBI (P=.02). The overall probability of disease-free survival (DFS) was 59% (SE, ±7%). It was 67% (SE, ±0.84%) after HTBI and 37% (SE, ±1.4%) after STBI (P=.01). Multivariate analyses showed the TBI schedule was the only risk factor that significantly affected relapse and DFS (P=.01 and P=.03, respectively). Conclusions: In patients with acute leukemia, HTBI is more efficacious than STBI in eradicating minimal residual disease after HLA-matched T cell–depleted hematopoietic stem cell transplantation, thus affecting DFS.« less

  16. FoxP3+ CD25+ CD8+ T-Cell Induction during Primary Simian Immunodeficiency Virus Infection in Cynomolgus Macaques Correlates with Low CD4+ T-Cell Activation and High Viral Load▿

    PubMed Central

    Karlsson, Ingrid; Malleret, Benoît; Brochard, Patricia; Delache, Benoît; Calvo, Julien; Le Grand, Roger; Vaslin, Bruno

    2007-01-01

    The early immune response fails to prevent the establishment of chronic human immunodeficiency virus (HIV) infection but may influence viremia during primary infection, thereby possibly affecting long-term disease progression. CD25+ FoxP3+ regulatory T cells may contribute to HIV/simian immunodeficiency virus (SIV) pathogenesis by suppressing efficient antiviral responses during primary infection, favoring high levels of viral replication and the establishment of chronic infection. In contrast, they may decrease immune activation during chronic infection. CD4+ regulatory T cells have been studied in the most detail, but CD8+ CD25+ FoxP3+ T cells also have regulatory properties. We monitored the dynamics of CD25+ FoxP3+ T cells during primary and chronic SIVmac251 infection in cynomolgus macaques. The number of peripheral CD4+ CD25+ FoxP3+ T cells paralleled that of memory CD4+ T cells, with a rapid decline during primary infection followed by a rebound to levels just below baseline and gradual depletion during the course of infection. No change in the proportion of CD25+ FoxP3+ T cells was observed in peripheral lymph nodes. A small number of CD4+ CD25+ FoxP3+ T cells at set point was associated with a high plasma viral load. In contrast, peripheral CD8+ CD25+ FoxP3+ T cells were induced a few days after peak plasma viral load during primary infection. The number of these cells was positively correlated with viral load and negatively correlated with CD4+ T-cell activation, SIV antigen-specific proliferative responses during primary infection, and plasma viral load at set point, with large numbers of CD8+ CD25+ FoxP3+ T cells being indicative of a poor prognosis. PMID:17898053

  17. Regulatory role of Vγ1 γδ T cells in tumor immunity through IL-4 production.

    PubMed

    Hao, Jianlei; Dong, Siyuan; Xia, Siyuan; He, Weifeng; Jia, Hao; Zhang, Song; Wei, Jun; O'Brien, Rebecca L; Born, Willi K; Wu, Zhenzhou; Wang, Puyue; Han, Jihong; Hong, Zhangyong; Zhao, Liqing; Yin, Zhinan

    2011-11-15

    It has been demonstrated that the two main subsets of peripheral γδ T cells, Vγ1 and Vγ4, have divergent functions in many diseases models. Recently, we reported that Vγ4 γδ T cells played a protective role in tumor immunity through eomesodermin-controlled mechanisms. However, the precise roles of Vγ1 γδ T cells in tumor immunity, especially whether Vγ1 γδ T cells have any interaction with Vγ4 γδ T cells, remain unknown. We demonstrated in this paper that Vγ1 γδ T cells suppressed Vγ4 γδ T cell-mediated antitumor function both in vitro and in vivo, and this suppression was cell contact independent. Using neutralizing anti-IL-4 Ab or IL-4(-/-) mice, we determined the suppressive factor derived from Vγ1 γδ T cells was IL-4. Indeed, treatment of Vγ4 γδ T cells with rIL-4 significantly reduced expression levels of NKG2D, perforin, and IFN-γ. Finally, Vγ1 γδ T cells produced more IL-4 and expressed significantly higher level of GATA-3 upon Th2 priming in comparison with Vγ4 γδ T cells. Therefore, to our knowledge, our results established for the first time a negative regulatory role of Vγ1 γδ T cells in Vγ4 γδ T cell-mediated antitumor immunity through cell contact-independent and IL-4-mediated mechanisms. Selective depletion of this suppressive subset of γδ T cells may be beneficial for tumor immune therapy.

  18. Dynein Separately Partners with NDE1 and Dynactin To Orchestrate T Cell Focused Secretion.

    PubMed

    Nath, Shubhankar; Christian, Laura; Tan, Sarah Youngsun; Ki, Sanghee; Ehrlich, Lauren I R; Poenie, Martin

    2016-09-15

    Helper and cytotoxic T cells accomplish focused secretion through the movement of vesicles toward the microtubule organizing center (MTOC) and translocation of the MTOC to the target contact site. In this study, using Jurkat cells and OT-I TCR transgenic primary murine CTLs, we show that the dynein-binding proteins nuclear distribution E homolog 1 (NDE1) and dynactin (as represented by p150(Glued)) form mutually exclusive complexes with dynein, exhibit nonoverlapping distributions in target-stimulated cells, and mediate different transport events. When Jurkat cells expressing a dominant negative form of NDE1 (NDE1-enhanced GFP fusion) were activated by Staphylococcus enterotoxin E-coated Raji cells, NDE1 and dynein failed to accumulate at the immunological synapse (IS) and MTOC translocation was inhibited. Knockdown of NDE1 in Jurkat cells or primary mouse CTLs also inhibited MTOC translocation and CTL-mediated killing. In contrast to NDE1, knockdown of p150(Glued), which depleted the alternative dynein/dynactin complex, resulted in impaired accumulation of CTLA4 and granzyme B-containing intracellular vesicles at the IS, whereas MTOC translocation was not affected. Depletion of p150(Glued) in CTLs also inhibited CTL-mediated lysis. We conclude that the NDE1/Lissencephaly 1 and dynactin complexes separately mediate two key components of T cell-focused secretion, namely translocation of the MTOC and lytic granules to the IS, respectively. Copyright © 2016 by The American Association of Immunologists, Inc.

  19. Hematopoietic stem cells with controllable tEpoR transgenes have a competitive advantage in bone marrow transplantation.

    PubMed

    Kirby, S; Walton, W; Smithies, O

    2000-06-15

    In a previous study, it was found that a truncated erythropoietin receptor transgene (tEpoR tg) enables multilineage hematopoietic progenitor amplification after treatment with erythropoietin (epo) in vitro and in vivo. This study used competitive bone marrow (BM) repopulation to show that tEpoR tg facilitates transplantation by hematopoietic stem cells (HSC). Individual multilineage colonies, committed myeloid progenitor colonies, and lymphoid colonies (pre-B colony-forming units) were grown from the marrow of animals 6 months after they received a 50/50 mixture of transgene and wild-type BM cells. In epo-treated recipients, the transgene-bearing cells significantly outcompeted the wild-type cells (84%-100% versus 16%-0%, respectively). In recipients treated with phosphate-buffered saline, the repopulation was minimally different from the donor mixture (49%-64% transgene versus 51%-36% wild-type). The epo-induced repopulation advantage is maintained in secondary transplants. In addition, neither accelerated HSC depletion nor uncontrollable proliferation occurred during epo-stimulated serial transplants of transgene-containing BM. Thus, the tEpoR tg functions in a benign fashion in HSC and allows for a significant and controllable repopulation advantage in vivo without excessive HSC depletion relative to wild-type BM. (Blood. 2000;95:3710-3715)

  20. Protection against Chlamydia psittaci in mice conferred by Lyt-2+ T cells.

    PubMed Central

    Buzoni-Gatel, D; Guilloteau, L; Bernard, F; Bernard, S; Chardès, T; Rocca, A

    1992-01-01

    A murine model was used to study the respective roles of L3T4+ and Lyt-2+ T cells in protection against Chlamydia psittaci. Donor mice were intravenously (i.v.) infected with 1 x 10(5) plaque-forming units (PFU) per mice of live C. psittaci. One month after inoculation, splenic cells from donors were transferred into syngenic recipients (5 x 10(7) cells/mouse). As measured by splenic colonization on Day 6 after i.v. challenge (1 x 10(5) PFU/mouse), transfer with primed (untreated) cells conferred a 3 log protection in this model. In vitro treatment, before transfer, of splenic cells with anti-Lyt-2 monoclonal antibody (mAb) and complement, markedly impaired the protection in comparison with control mice transferred with primed untreated cells, whereas treatment with anti-L3T4 mAb did not reduce the transferred protection. Resistance to a reinfection with C. psittaci was also studied after selective in vivo depletion of L3T4+ and Lyt-2+ T cells. One month after primary infection, mice were treated with anti-L3T4 or anti-Lyt-2 mAb and challenged thereafter (i.v., 1 x 10(5) PFU). The splenic colonization on Day 6 after challenge demonstrated that treatment with anti-Lyt-2 mAb impaired resistance against a subsequent infection with C. psittaci. Treatment with anti-L3T4 mAb in vivo had no effect on protection, as previously described in vitro. The mechanisms by which Lyt-2+ T cells could participate in the elimination of bacteria were discussed. PMID:1427980