Clinical outcomes of a novel therapeutic vaccine with Tax peptide-pulsed dendritic cells for adult T cell leukaemia/lymphoma in a pilot study.

PubMed

Suehiro, Youko; Hasegawa, Atsuhiko; Iino, Tadafumi; Sasada, Amane; Watanabe, Nobukazu; Matsuoka, Masao; Takamori, Ayako; Tanosaki, Ryuji; Utsunomiya, Atae; Choi, Ilseung; Fukuda, Tetsuya; Miura, Osamu; Takaishi, Shigeo; Teshima, Takanori; Akashi, Koichi; Kannagi, Mari; Uike, Naokuni; Okamura, Jun

2015-05-01

Adult T cell leukaemia/lymphoma (ATL) is a human T cell leukaemia virus type-I (HTLV-I)-infected T cell malignancy with poor prognosis. We herein developed a novel therapeutic vaccine designed to augment an HTLV-I Tax-specific cytotoxic T lymphocyte (CTL) response that has been implicated in anti-ATL effects, and conducted a pilot study to investigate its safety and efficacy. Three previously treated ATL patients, classified as intermediate- to high-risk, were subcutaneously administered with the vaccine, consisting of autologous dendritic cells (DCs) pulsed with Tax peptides corresponding to the CTL epitopes. In all patients, the performance status improved after vaccination without severe adverse events, and Tax-specific CTL responses were observed with peaks at 16-20 weeks. Two patients achieved partial remission in the first 8 weeks, one of whom later achieved complete remission, maintaining their remission status without any additional chemotherapy 24 and 19 months after vaccination, respectively. The third patient, whose tumour cells lacked the ability to express Tax at biopsy, obtained stable disease in the first 8 weeks and later developed slowly progressive disease although additional therapy was not required for 14 months. The clinical outcomes of this pilot study indicate that the Tax peptide-pulsed DC vaccine is a safe and promising immunotherapy for ATL. © 2015 John Wiley & Sons Ltd.

T-cell tropism of simian T-cell leukaemia virus type 1 and cytokine profiles in relation to proviral load and immunological changes during chronic infection of naturally infected mandrills (Mandrillus sphinx).

PubMed

Souquière, Sandrine; Mouinga-Ondeme, Augustin; Makuwa, Maria; Beggio, Paola; Radaelli, Antonia; De Giuli Morghen, Carlo; Mortreux, Franck; Kazanji, Mirdad

2009-08-01

Although a wide variety of non-human primates are susceptible to simian T-cell leukaemia virus type 1 (STLV-1), little is known about the virological or molecular determinants of natural STLV-1 infection. We determined STLV-1 virus tropism in vivo and its relation to the immune response by evaluating cytokine production and T-cell subsets in naturally infected and uninfected mandrills. With real-time PCR methods, we found that STLV-1 in mandrills infects both CD4(+) and CD8(+) T cells; however, proviral loads were significantly higher (P = 0.01) in CD4(+) than in CD8(+) cells (mean STLV-1 copies number per 100 cells (+/- SD) was 7.8 +/- 8 in CD4(+) T cells and 3.9 +/- 4.5 in CD8(+) T cells). After culture, STLV-1 provirus was detected in enriched CD4(+) but not in enriched CD8(+) T cells. After 6 months of culture, STLV-1-transformed cell lines expressing CD3(+), CD4(+) and HLADR(+) were established, and STLV-1 proteins and tax/rex mRNA were detected. In STLV-1 infected monkeys, there was a correlation between high proviral load and elevated levels of interleukin (IL)-2, IL-6, IL-10, interferon-gamma and tumour necrosis factor-alpha. The two monkeys with the highest STLV-1 proviral load had activated CD4(+)HLADR(+) and CD8(+)HLADR(+) T-cell subsets and a high percentage of CD25(+) in CD4(+) and CD8(+) T cells. Our study provides the first cellular, immunological and virological characterization of natural STLV-1 infection in mandrills and shows that they are an appropriate animal model for further physiopathological studies of the natural history of human T-cell leukaemia viruses.

Adult T-cell leukaemia/lymphoma can mimic other lymphomas in a non-endemic area: dilemmas in diagnosis and treatment.

PubMed

Huang, C-T; Lee, Y-H; Chow, K-C; Yang, C-F; Chen, P C-H; Hsiao, L-T; Gau, J-P; Tzeng, C-H; Liu, C-Y; Chiou, T-J

2014-04-01

The diagnosis of Adult T-cell leukaemia/lymphoma (ATL) in non-endemic regions is challenging. This study analyses the clinicopathologic features and diagnostic processes of ATL patients in Taiwan. ATL patients diagnosed and treated at Taipei Veterans General Hospital from 1998 through 2010 were retrospectively identified. The diagnosis of ATL was confirmed by in situ detection of human T-cell leukaemia virus type 1 (HTLV-1) when necessary. Patients' data were reviewed and analysed. Fourteen ATL patients were identified, among whom six (42.9%) had an antecedent diagnosis of other malignant lymphomas before the ATL diagnosis, including two diagnosed with Hodgkin disease (HD), one with peripheral T-cell lymphoma, two with chronic lymphocytic leukaemia and one with angioimmunoblastic T-cell lymphoma. Of the 14 patients, eight (57%) were subclassified as the acute type, three (21.4%) as the lymphoma type, and three (21.4%) as the chronic type ATL. Five of six (83.3%) patients with initial non-ATL misdiagnosis were diagnosed with non-acute type ATL. In particular, a patient with an antecedent diagnosis of HD presented with typical Reed-Sternberg (RS)-like cells harbouring Epstein-Barr virus genomes in affected lymph nodes. The patient progressed to acute type ATL 3 years after the initial diagnosis, and HTLV-1 genomes were identified in the previous RS-like cells. In non-endemic areas, such as Taiwan, ATL, particularly the non-acute type, may mimic other lymphomas and easily be misdiagnosed. HTLV-1 serology should be routinely screened in all malignant lymphoma patients. In situ detection of HTLV-1 is helpful in cases with diagnostic dilemmas. © 2014 The Authors; Internal Medicine Journal © 2014 Royal Australasian College of Physicians.

Age-related clinical and biological features of PTEN abnormalities in T-cell acute lymphoblastic leukaemia.

PubMed

Tesio, M; Trinquand, A; Ballerini, P; Hypolite, G; Lhermitte, L; Petit, A; Ifrah, N; Baruchel, A; Dombret, H; Macintyre, E; Asnafi, V

2017-12-01

The tumour suppressor gene PTEN is commonly altered in T-cell acute lymphoblastic leukaemia but its prognostic impact is still debated. We screened a cohort of 573 fully characterised adult and paediatric T-cell acute lymphoblastic leukaemia (T-ALL) patients for genomic PTEN abnormalities. PTEN-inactivating mutations and/or deletions were identified in 91 cases (16%), including 18% of paediatric (49/277) and 14% of adult cases (42/296). Thirty-four patients harboured only mutations, 12 cases demonstrated only large deletions and 9 only microdeletions. About 36 patients had combined alterations. Different mechanisms of PTEN inactivation predicted differences in the clinical outcome for both adult and paediatric patients treated according to the GRAALL03/05 and FRALLE2000 protocols. Whereas large deletions predicted lower 5-year overall survival (P=0.0053 in adults, P=0.001 in children) and disease-free survival (P=0.0009 in adults, P=0.0002 in children), mutations were not associated with a worse prognosis. The prognostic impact of PTEN loss is therefore linked to the underlying type of genomic abnormality, both in adult and paediatric T-ALLs, demonstrating that detailed analysis of the type of abnormality type would be useful to refine risk stratification.

Effects of the HIF1 inhibitor, echinomycin, on growth and NOTCH signalling in leukaemia cells.

PubMed

Yonekura, Satoru; Itoh, Mai; Okuhashi, Yuki; Takahashi, Yusuke; Ono, Aya; Nara, Nobuo; Tohda, Shuji

2013-08-01

To examine the effects of echinomycin, a compound that inhibits DNA-binding activity of hypoxia-inducible factor-1 (HIF1), on leukaemia cell growth. Three acute myeloid leukaemia cell lines and three T-lymphoblastic leukaemia cell lines were cultured with echinomycin. Cell growth, mRNA and protein expression levels were examined by WST-1 assay, reverse-transcription polymerase chain reaction and immunoblotting, respectively. HIF1α protein was expressed in all cell lines under normoxia. Treatment with echinomycin suppressed cell growth and induced apoptosis in association with decreased mRNA expression of HIF1 targets, glucose transporter-1 (GLUT1) and B-cell CLL/lymphoma-2 (BCL2). Echinomycin also suppressed the protein expression of NOTCH1, cleaved NOTCH1, v-myc myelocytomatosis viral oncogene homolog (MYC), v-akt murine thymoma viral oncogene homolog-1 (AKT), phosphorylated AKT, mechanistic target of rapamycin (mTOR), and phosphorylated mTOR and increased that of cleaved caspase-3 in some cell lines. Echinomycin suppresses leukaemia cell growth in association with reduced NOTCH1 expression. This is the first report to show that HIF inhibitor treatment suppresses NOTCH1 signalling. HIF inhibitors could be novel candidates for a molecular-targeted therapy against leukaemia.

Leukaemic infiltration and cytomegalovirus retinitis in a patient with acute T-cell lymphoblastic leukaemia in complete remission.

PubMed

Saldaña Garrido, J D; Martínez Rubio, M; Carrión Campo, R; Moya Moya, M A; Rico Sergado, L

2017-03-01

A 43-year-old woman in remission from T- cell acute lymphoblastic leukaemia was referred to our hospital with suspected leukaemic retinitis. The funduscopic examination of her left eye revealed multifocal yellow-white peripheral retinitis and retinal haemorrhage. The patient was treated for cytomegalovirus retinitis after an extended haematological investigation showed no abnormalities. Initial improvement was followed by papillitis in the left eye and motility restriction in the right eye. Magnetic resonance and lumbar puncture confirmed leukaemia relapse. Specific treatment was initiated with complete resolution. Ocular involvement may precede haematological leukaemia relapse. Physicians should be alerted when ocular symptoms appear in these cases. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

Expression pattern of immunosurveillance-related antigen in adult T cell leukaemia/lymphoma.

PubMed

Asano, Naoko; Miyoshi, Hiroaki; Kato, Takeharu; Shimono, Joji; Yoshida, Noriaki; Kurita, Daisuke; Sasaki, Yuya; Kawamoto, Keisuke; Ohshima, Koichi; Seto, Masao

2018-05-01

Adult T cell leukaemia/lymphoma (ATLL) is an aggressive malignancy with a poor prognosis. Human leucocyte antigen (HLA) and β2 microglobulin (β2M) serve as key molecules in tumour immunity, and their expression is reduced frequently in tumour cells. Programmed cell death (PD)-1/PD-ligand1 (PD-L1) interactions play a role in escape of tumour cells from T cell immunity. Therefore, this study aimed to determine the clinicopathological relevance of HLA and β2M expressions in ATLL cells and PD-L1 expression in lymphoma or stromal cells and predict the overall survival of patients with ATLL. We analysed a total of 123 biopsy samples from patients newly diagnosed with ATLL by using immunohistochemical analysis. Of the patients enrolled, 91 (74%) were positive for HLA (in cell membrane, 60 patients), 89 (72%) were positive for β2M (in cell membrane, 54 patients) and 48 (39%) were positive for both HLA and β2M in the cell membrane (HLA m+ β2M m+ ). No significant clinical differences other than prognosis were found between the HLA m+ β2M m+ group and the other groups. Immunophenotypical evaluation revealed significantly higher rates of CD30-positive lymphoma cells (P = 0.003) and PD-L1-positive stromal cells in microenvironments (miPD-L1 high ) (P = 0.011) of the HLA m+ β2M m+ group than in the other groups. The HLA m+ β2M m+ group had a significantly better prognosis that the other groups (P = 0.0096), and patients showing HLA m+ β2M m+ with miPD-L1 high had the most favourable prognosis among all groups. The membranous expression of HLA and β2M is likely to reflect the immune response and would be useful to predict prognosis before starting ATLL therapy. © 2018 John Wiley & Sons Ltd.

Low-expression of E-cadherin in leukaemia cells causes loss of homophilic adhesion and promotes cell growth.

PubMed

Rao, Qing; Wang, Ji-Ying; Meng, Jihong; Tang, Kejing; Wang, Yanzhong; Wang, Min; Xing, Haiyan; Tian, Zheng; Wang, Jianxiang

2011-09-01

E-cadherin (epithelial cadherin) belongs to the calcium-dependent adhesion molecule superfamily and is implicated in the interactions of haematopoietic progenitors and bone marrow stromal cells. Adhesion capacity to bone marrow stroma was impaired for leukaemia cells, suggesting that a breakdown of adhesive mechanisms governed by an adhesion molecule may exist in leukaemic microenvironment. We previously found that E-cadherin was low expressed in primary acute leukaemia cells compared with normal bone marrow mononuclear cells. In this study, we investigate the functional importance of low E-cadherin expression in leukaemia cell behaviours and investigate its effects in the abnormal interaction of leukaemic cells with stromal cells. After expression of E-cadherin was restored by a demethylating agent in leukaemia cells, E-cadherin-specific adhesion was enhanced. Additionally, siRNA (small interfering RNA)-mediated silencing of E-cadherin in Raji cells resulted in a reduction of cell homophilic adhesion and enhancement of cell proliferation and colony formation. These results suggest that low expression of E-cadherin contributes to the vigorous growth and transforming ability of leukaemic cells.

Association of a murine leukaemia stem cell gene signature based on nucleostemin promoter activity with prognosis of acute myeloid leukaemia in patients.

PubMed

Ali, Mohamed A E; Naka, Kazuhito; Yoshida, Akiyo; Fuse, Kyoko; Kasada, Atsuo; Hoshii, Takayuki; Tadokoro, Yuko; Ueno, Masaya; Ohta, Kumiko; Kobayashi, Masahiko; Takahashi, Chiaki; Hirao, Atsushi

2014-07-18

Acute myeloid leukaemia (AML) is a heterogeneous neoplastic disorder in which a subset of cells function as leukaemia-initiating cells (LICs). In this study, we prospectively evaluated the leukaemia-initiating capacity of AML cells fractionated according to the expression of a nucleolar GTP binding protein, nucleostemin (NS). To monitor NS expression in living AML cells, we generated a mouse AML model in which green fluorescent protein (GFP) is expressed under the control of a region of the NS promoter (NS-GFP). In AML cells, NS-GFP levels were correlated with endogenous NS mRNA. AML cells with the highest expression of NS-GFP were very immature blast-like cells, efficiently formed leukaemia colonies in vitro, and exhibited the highest leukaemia-initiating capacity in vivo. Gene expression profiling analysis revealed that cell cycle regulators and nucleotide metabolism-related genes were highly enriched in a gene set associated with leukaemia-initiating capacity that we termed the 'leukaemia stem cell gene signature'. This gene signature stratified human AML patients into distinct clusters that reflected prognosis, demonstrating that the mouse leukaemia stem cell gene signature is significantly associated with the malignant properties of human AML. Further analyses of gene regulation in leukaemia stem cells could provide novel insights into diagnostic and therapeutic approaches to AML. Copyright © 2014 Elsevier Inc. All rights reserved.

Anti-leukaemic activity of the TYK2 selective inhibitor NDI-031301 in T-cell acute lymphoblastic leukaemia.

PubMed

Akahane, Koshi; Li, Zhaodong; Etchin, Julia; Berezovskaya, Alla; Gjini, Evisa; Masse, Craig E; Miao, Wenyan; Rocnik, Jennifer; Kapeller, Rosana; Greenwood, Jeremy R; Tiv, Hong; Sanda, Takaomi; Weinstock, David M; Look, A Thomas

2017-04-01

Activation of tyrosine kinase 2 (TYK2) contributes to the aberrant survival of T-cell acute lymphoblastic leukaemia (T-ALL) cells. Here we demonstrate the anti-leukaemic activity of a novel TYK2 inhibitor, NDI-031301. NDI-031301 is a potent and selective inhibitor of TYK2 that induced robust growth inhibition of human T-ALL cell lines. NDI-031301 treatment of human T-ALL cell lines resulted in induction of apoptosis that was not observed with the JAK inhibitors tofacitinib and baricitinib. Further investigation revealed that NDI-031301 treatment uniquely leads to activation of three mitogen-activated protein kinases (MAPKs), resulting in phosphorylation of ERK, SAPK/JNK and p38 MAPK coincident with PARP cleavage. Activation of p38 MAPK occurred within 1 h of NDI-031301 treatment and was responsible for NDI-031301-induced T-ALL cell death, as pharmacological inhibition of p38 MAPK partially rescued apoptosis induced by TYK2 inhibitor. Finally, daily oral administration of NDI-031301 at 100 mg/kg bid to immunodeficient mice engrafted with KOPT-K1 T-ALL cells was well tolerated, and led to decreased tumour burden and a significant survival benefit. These results support selective inhibition of TYK2 as a promising potential therapeutic strategy for T-ALL. © 2017 John Wiley & Sons Ltd.

T cells expressing CD19 chimeric antigen receptors for acute lymphoblastic leukaemia in children and young adults: a phase 1 dose-escalation trial.

PubMed

Lee, Daniel W; Kochenderfer, James N; Stetler-Stevenson, Maryalice; Cui, Yongzhi K; Delbrook, Cindy; Feldman, Steven A; Fry, Terry J; Orentas, Rimas; Sabatino, Marianna; Shah, Nirali N; Steinberg, Seth M; Stroncek, Dave; Tschernia, Nick; Yuan, Constance; Zhang, Hua; Zhang, Ling; Rosenberg, Steven A; Wayne, Alan S; Mackall, Crystal L

2015-02-07

Chimeric antigen receptor (CAR) modified T cells targeting CD19 have shown activity in case series of patients with acute and chronic lymphocytic leukaemia and B-cell lymphomas, but feasibility, toxicity, and response rates of consecutively enrolled patients treated with a consistent regimen and assessed on an intention-to-treat basis have not been reported. We aimed to define feasibility, toxicity, maximum tolerated dose, response rate, and biological correlates of response in children and young adults with refractory B-cell malignancies treated with CD19-CAR T cells. This phase 1, dose-escalation trial consecutively enrolled children and young adults (aged 1-30 years) with relapsed or refractory acute lymphoblastic leukaemia or non-Hodgkin lymphoma. Autologous T cells were engineered via an 11-day manufacturing process to express a CD19-CAR incorporating an anti-CD19 single-chain variable fragment plus TCR zeta and CD28 signalling domains. All patients received fludarabine and cyclophosphamide before a single infusion of CD19-CAR T cells. Using a standard 3 + 3 design to establish the maximum tolerated dose, patients received either 1 × 10(6) CAR-transduced T cells per kg (dose 1), 3 × 10(6) CAR-transduced T cells per kg (dose 2), or the entire CAR T-cell product if sufficient numbers of cells to meet the assigned dose were not generated. After the dose-escalation phase, an expansion cohort was treated at the maximum tolerated dose. The trial is registered with ClinicalTrials.gov, number NCT01593696. Between July 2, 2012, and June 20, 2014, 21 patients (including eight who had previously undergone allogeneic haematopoietic stem-cell transplantation) were enrolled and infused with CD19-CAR T cells. 19 received the prescribed dose of CD19-CAR T cells, whereas the assigned dose concentration could not be generated for two patients (90% feasible). All patients enrolled were assessed for response. The maximum tolerated dose was defined as 1 × 10

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.

Alginate foam-based three-dimensional culture to investigate drug sensitivity in primary leukaemia cells.

PubMed

Karimpoor, Mahroo; Yebra-Fernandez, Eva; Parhizkar, Maryam; Orlu, Mine; Craig, Duncan; Khorashad, Jamshid S; Edirisinghe, Mohan

2018-04-01

The development of assays for evaluating the sensitivity of leukaemia cells to anti-cancer agents is becoming an important aspect of personalized medicine. Conventional cell cultures lack the three-dimensional (3D) structure of the bone marrow (BM), the extracellular matrix and stromal components which are crucial for the growth and survival of leukaemia stem cells. To accurately predict the sensitivity of the leukaemia cells in an in vitro assay a culturing system containing the essential components of BM is required. In this study, we developed a porous calcium alginate foam-based scaffold to be used for 3D culture. The new 3D culture was shown to be cell compatible as it supported the proliferation of both normal haematopoietic and leukaemia cells. Our cell differential assay for myeloid markers showed that the porous foam-based 3D culture enhanced myeloid differentiation in both leukaemia and normal haematopoietic cells compared to two-dimensional culture. The foam-based scaffold reduced the sensitivity of the leukaemia cells to the tested antileukaemia agents in K562 and HL60 leukaemia cell line model and also primary myeloid leukaemia cells. This observation supports the application of calcium alginate foams as scaffold components of the 3D cultures for investigation of sensitivity to antileukaemia agents in primary myeloid cells. © 2018 The Author(s).

Tracing the origins of relapse in acute myeloid leukaemia to stem cells.

PubMed

Shlush, Liran I; Mitchell, Amanda; Heisler, Lawrence; Abelson, Sagi; Ng, Stanley W K; Trotman-Grant, Aaron; Medeiros, Jessie J F; Rao-Bhatia, Abilasha; Jaciw-Zurakowsky, Ivana; Marke, Rene; McLeod, Jessica L; Doedens, Monica; Bader, Gary; Voisin, Veronique; Xu, ChangJiang; McPherson, John D; Hudson, Thomas J; Wang, Jean C Y; Minden, Mark D; Dick, John E

2017-07-06

In acute myeloid leukaemia, long-term survival is poor as most patients relapse despite achieving remission. Historically, the failure of therapy has been thought to be due to mutations that produce drug resistance, possibly arising as a consequence of the mutagenic properties of chemotherapy drugs. However, other lines of evidence have pointed to the pre-existence of drug-resistant cells. For example, deep sequencing of paired diagnosis and relapse acute myeloid leukaemia samples has provided direct evidence that relapse in some cases is generated from minor genetic subclones present at diagnosis that survive chemotherapy, suggesting that resistant cells are generated by evolutionary processes before treatment and are selected by therapy. Nevertheless, the mechanisms of therapy failure and capacity for leukaemic regeneration remain obscure, as sequence analysis alone does not provide insight into the cell types that are fated to drive relapse. Although leukaemia stem cells have been linked to relapse owing to their dormancy and self-renewal properties, and leukaemia stem cell gene expression signatures are highly predictive of therapy failure, experimental studies have been primarily correlative and a role for leukaemia stem cells in acute myeloid leukaemia relapse has not been directly proved. Here, through combined genetic and functional analysis of purified subpopulations and xenografts from paired diagnosis/relapse samples, we identify therapy-resistant cells already present at diagnosis and two major patterns of relapse. In some cases, relapse originated from rare leukaemia stem cells with a haematopoietic stem/progenitor cell phenotype, while in other instances relapse developed from larger subclones of immunophenotypically committed leukaemia cells that retained strong stemness transcriptional signatures. The identification of distinct patterns of relapse should lead to improved methods for disease management and monitoring in acute myeloid leukaemia

Mechanistic mathematical modelling of mercaptopurine effects on cell cycle of human acute lymphoblastic leukaemia cells

PubMed Central

Panetta, J C; Evans, W E; Cheok, M H

2006-01-01

The antimetabolite mercaptopurine (MP) is widely used to treat childhood acute lymphoblastic leukaemia (ALL). To study the dynamics of MP on the cell cycle, we incubated human T-cell leukaemia cell lines (Molt-4 sensitive and resistant subline and P12 resistant) with 10 μM MP and measured total cell count, cell cycle distribution, percent viable, percent apoptotic, and percent dead cells serially over 72 h. We developed a mathematical model of the cell cycle dynamics after treatment with MP and used it to show that the Molt-4 sensitive controls had a significantly higher rate of cells entering apoptosis (2.7-fold, P<0.00001) relative to the resistant cell lines. Additionally, when treated with MP, the sensitive cell line showed a significant increase in the rate at which cells enter apoptosis compared to its controls (2.4-fold, P<0.00001). Of note, the resistant cell lines had a higher rate of antimetabolite incorporation into the DNA of viable cells (>1.4-fold, P<0.01). Lastly, in contrast to the other cell lines, the Molt-4 resistant subline continued to cycle, though at a rate slower relative to its control, rather than proceed to apoptosis. This led to a larger S-phase block in the Molt-4 resistant cell line, but not a higher rate of cell death. Gene expression of apoptosis, cell cycle, and repair genes were consistent with mechanistic dynamics described by the model. In summary, the mathematical model provides a quantitative assessment to compare the cell cycle effects of MP in cells with varying degrees of MP resistance. PMID:16333308

Loss of oncogenic Notch1 with resistance to a PI3K inhibitor in T-cell leukaemia.

PubMed

Dail, Monique; Wong, Jason; Lawrence, Jessica; O'Connor, Daniel; Nakitandwe, Joy; Chen, Shann-Ching; Xu, Jin; Lee, Leslie B; Akagi, Keiko; Li, Qing; Aster, Jon C; Pear, Warren S; Downing, James R; Sampath, Deepak; Shannon, Kevin

2014-09-25

Mutations that deregulate Notch1 and Ras/phosphoinositide 3 kinase (PI3K)/Akt signalling are prevalent in T-cell acute lymphoblastic leukaemia (T-ALL), and often coexist. Here we show that the PI3K inhibitor GDC-0941 is active against primary T-ALLs from wild-type and Kras(G12D) mice, and addition of the MEK inhibitor PD0325901 increases its efficacy. Mice invariably relapsed after treatment with drug-resistant clones, most of which unexpectedly had reduced levels of activated Notch1 protein, downregulated many Notch1 target genes, and exhibited cross-resistance to γ-secretase inhibitors. Multiple resistant primary T-ALLs that emerged in vivo did not contain somatic Notch1 mutations present in the parental leukaemia. Importantly, resistant clones upregulated PI3K signalling. Consistent with these data, inhibiting Notch1 activated the PI3K pathway, providing a likely mechanism for selection against oncogenic Notch1 signalling. These studies validate PI3K as a therapeutic target in T-ALL and raise the unexpected possibility that dual inhibition of PI3K and Notch1 signalling could promote drug resistance in T-ALL.

Fusion of NUP98 and the SET binding protein 1 (SETBP1) gene in a paediatric acute T cell lymphoblastic leukaemia with t(11;18)(p15;q12).

PubMed

Panagopoulos, Ioannis; Kerndrup, Gitte; Carlsen, Niels; Strömbeck, Bodil; Isaksson, Margareth; Johansson, Bertil

2007-01-01

Three NUP98 chimaeras have previously been reported in T cell acute lymphoblastic leukaemia (T-ALL): NUP98/ADD3, NUP98/CCDC28A, and NUP98/RAP1GDS1. We report a T-ALL with t(11;18)(p15;q12) resulting in a novel NUP98 fusion. Fluorescent in situ hybridisation showed NUP98 and SET binding protein 1(SETBP1) fusion signals; other analyses showed that exon 12 of NUP98 was fused in-frame with exon 5 of SETBP1. Nested polymerase chain reaction did not amplify the reciprocal SETBP1/NUP98, suggesting that NUP98/SETBP1 transcript is pathogenetically important. SETBP1 has previously not been implicated in leukaemias; however, it encodes a protein that specifically interacts with SET, fused to NUP214 in a case of acute undifferentiated leukaemia.

Primary distal femur T-cell lymphoma after allogeneic haematopoietic stem cell transplantation for chronic myeloid leukaemia: a rare case report and literature review.

PubMed

Han, Qiaoyan; Sun, Miao; Wu, Lingyu; Chen, Jing; Wang, Wei; Liu, Chunhua; Chen, Haoyue; Du, Guibin

2014-04-01

Post-transplant lymphoproliferative disorders originating from T lymphocytes are a rare complication of allogeneic haematopoietic stem cell transplantation (allo-HSCT) that are not usually associated with Epstein-Barr virus infection. A male patient diagnosed at the age of 15 years with chronic myeloid leukaemia (in the chronic phase) was initially treated with oral hydroxyurea. The disease entered an accelerated phase when the patient was 22 years old. Complete remission was achieved after one course of homoharringtonine and cytarabine. The patient then underwent human leucocyte antigen-matched sibling donor allo-HSCT. Just over 6.5 years after the allo-HSCT, a second primary tumour was located in the distal femur and diagnosed as T-cell non-Hodgkin's lymphoma (stage IV, group B). This was treated with various chemotherapy and radiotherapy regimens, but the outcomes were poor and the disease progressed. The T-cell lymphoma invaded many sites, including the skeleton, spleen and skin, and the patient died within 8 months of the diagnosis. This current case report highlights the need for the early detection and prevention of subsequent primary malignancies after allo-HSCT.

Distinctive genotypes in infants with T-cell acute lymphoblastic leukaemia.

PubMed

Mansur, Marcela B; van Delft, Frederik W; Colman, Susan M; Furness, Caroline L; Gibson, Jane; Emerenciano, Mariana; Kempski, Helena; Clappier, Emmanuelle; Cave, Hélène; Soulier, Jean; Pombo-de-Oliveira, Maria S; Greaves, Mel; Ford, Anthony M

2015-11-01

Infant T-cell acute lymphoblastic leukaemia (iT-ALL) is a very rare and poorly defined entity with a poor prognosis. We assembled a unique series of 13 infants with T-ALL, which allowed us to identify genotypic abnormalities and to investigate prenatal origins. Matched samples (diagnosis/remission) were analysed by single nucleotide polymorphism-array to identify genomic losses and gains. In three cases, we identified a recurrent somatic deletion on chromosome 3. These losses result in the complete deletion of MLF1 and have not previously been described in T-ALL. We observed two cases with an 11p13 deletion (LMO2-related), one of which also harboured a deletion of RB1. Another case presented a large 11q14·1-11q23·2 deletion that included ATM and only five patients (38%) showed deletions of CDKN2A/B. Four cases showed NOTCH1 mutations; in one case FBXW7 was the sole mutation and three cases showed alterations in PTEN. KMT2A rearrangements (KMT2A-r) were detected in three out of 13 cases. For three patients, mutations and copy number alterations (including deletion of PTEN) could be backtracked to birth using neonatal blood spot DNA, demonstrating an in utero origin. Overall, our data indicates that iT-ALL has a diverse but distinctive profile of genotypic abnormalities when compared to T-ALL in older children and adults. © 2015 The Authors. British Journal of Haematology published by John Wiley & Sons Ltd.

Infection with human herpesvirus type 8 and human T-cell leukaemia virus type 1 among individuals participating in a case–control study in Havana City, Cuba

PubMed Central

Fernandez, L; Serraino, D; Rezza, G; Lence, J; Ortiz, R M; Cruz, T; Vaccarella, S; Sarmati, L; Andreoni, M; Franceschi, S

2002-01-01

Infection with human herpesvirus type 8 and with human T-cell leukaemia virus type-1 shows strong geographic variations. We conducted this study to assess prevalence and risk factors for human herpesvirus type 8 infection in Havana City, Cuba. Information and residual serum samples already collected for a hospital based case–control study were used. A total of 379 individuals (267 males and 112 females; median age=63 years) were evaluated. Antibodies to the lytic antigen of human herpesvirus type 8 were detected by using an immunofluorescence assay, while human T-cell leukaemia virus type-1 serology was performed by means of an ELISA test (alpha Biotech). Overall, 64 subjects (16.9%, 95% confidence interval: 13.1–20.0) were positive for human herpesvirus type 8 antibodies. Human herpesvirus type 8 seroprevalence significantly increased with age (odds ratio=1.9 for ⩾65 vs <55 years), and was twice as frequent in blacks than in whites. No association emerged with gender, socio-economic indicators, family size, history of sexually transmitted disease, sexual behaviour. Overall, 16 persons had anti-human T-cell leukaemia virus type-1 antibodies (4.2%, 95% confidence interval: 2.2–6.4). No relationship emerged between human T-cell leukaemia virus type-1 and human herpesvirus type 8 serostatus. The study findings indicate that human herpesvirus type 8 infection is relatively common in Havana City, Cuba, suggesting that Cuba may represent an intermediate endemical area. Sexual transmission does not seem to play a major role in the spread human herpesvirus type 8 infection. British Journal of Cancer (2002) 87, 1253–1256. doi:10.1038/sj.bjc.6600613 www.bjcancer.com © 2002 Cancer Research UK PMID:12439714

Single-cell heterogeneity and cell-cycle-related viral gene bursts in the human leukaemia virus HTLV-1

PubMed Central

Billman, Martin R; Rueda, David; Bangham, Charles R M

2017-01-01

Background: The human leukaemia virus HTLV-1 expresses essential accessory genes that manipulate the expression, splicing and transport of viral mRNAs.  Two of these genes, tax and hbz, also promote proliferation of the infected cell, and both genes are thought to contribute to oncogenesis in adult T-cell leukaemia/lymphoma.  The regulation of HTLV-1 proviral latency is not understood.  tax, on the proviral plus strand, is usually silent in freshly-isolated cells, whereas the minus-strand-encoded hbz gene is persistently expressed at a low level.  However, the persistently activated host immune response to Tax indicates frequent expression of tax in vivo.  Methods: We used single-molecule RNA-FISH to quantify the expression of HTLV-1 transcripts at the single-cell level in a total of >19,000 cells from five T-cell clones, naturally infected with HTLV-1, isolated by limiting dilution from peripheral blood of HTLV-1-infected subjects.  Results: We found strong heterogeneity both within and between clones in the expression of the proviral plus-strand (detected by hybridization to the tax gene) and the minus-strand ( hbz gene). Both genes are transcribed in bursts; tax expression is enhanced in the absence of hbz, while hbz expression increased in cells with high tax expression. Surprisingly, we found that hbz expression is strongly associated with the S and G 2/M phases of the cell cycle, independent of tax expression.  Contrary to current belief, hbz is not expressed in all cells at all times, even within one clone.  In hbz-positive cells, the abundance of hbz transcripts showed a very strong positive linear correlation with nuclear volume. Conclusions: The occurrence of intense, intermittent plus-strand gene bursts in independent primary HTLV-1-infected T-cell clones from unrelated individuals strongly suggests that the HTLV-1 plus-strand is expressed in bursts in vivo.  Our results offer an explanation for the paradoxical correlations observed between

Haemopoietic stem cell transplantation for acute lymphoblastic leukaemia.

PubMed

Popat, Uday; Carrum, George; Heslop, Helen E

2003-02-01

The majority of children and some adults with acute lymphocytic leukaemia (ALL) can be cured with current intensive chemotherapy regimens. For those patients who relapse or who do not achieve remission, allogeneic haemopoietic stem cell transplantation (HSCT) offers the best chance for long-term disease control. Different sources of haemopoietic stem cells including marrow, peripheral blood, and cord blood are now available and the introduction of subablative regimens has increased the number of patients who are transplant candidates. Relapse remains the major cause of transplant failure and immunotherapy strategies post-transplant to augment the graft versus leukaemia effect are being explored.

Gynecomastia in a case of hairy cell leukaemia--cladribine induced?

PubMed

Abhyankar, D; Saikia, T; Advani, S

2001-06-01

Gynecomastia is benign enlargement of the male breast and is commonly drug induced. Various drugs are responsible and chemotherapeutic drugs can also cause gynecomastia. Cladribine is now widely used for the treatment of hairy cell leukaemia. We present a case report of development of unilateral gynecomastia in a case of hairy cell leukaemia treated with cladribine and question whether this was induced by the chemotherapy.

Acute B lymphoblastic leukaemia-propagating cells are present at high frequency in diverse lymphoblast populations

PubMed Central

Rehe, Klaus; Wilson, Kerrie; Bomken, Simon; Williamson, Daniel; Irving, Julie; den Boer, Monique L; Stanulla, Martin; Schrappe, Martin; Hall, Andrew G; Heidenreich, Olaf; Vormoor, Josef

2013-01-01

Leukaemia-propagating cells are more frequent in high-risk acute B lymphoblastic leukaemia than in many malignancies that follow a hierarchical cancer stem cell model. It is unclear whether this characteristic can be more universally applied to patients from non-‘high-risk’ sub-groups and across a broad range of cellular immunophenotypes. Here, we demonstrate in a wide range of primary patient samples and patient samples previously passaged through mice that leukaemia-propagating cells are found in all populations defined by high or low expression of the lymphoid differentiation markers CD10, CD20 or CD34. The frequency of leukaemia-propagating cells and their engraftment kinetics do not differ between these populations. Transcriptomic analysis of CD34high and CD34low blasts establishes their difference and their similarity to comparable normal progenitors at different stages of B-cell development. However, consistent with the functional similarity of these populations, expression signatures characteristic of leukaemia propagating cells in acute myeloid leukaemia fail to distinguish between the different populations. Together, these findings suggest that there is no stem cell hierarchy in acute B lymphoblastic leukaemia. PMID:23229821

Terminal deoxynucleotidyl transferase (TdT)-negative T-cell lymphoblastic lymphoma with loss of the T-cell lineage-specific marker CD3 at relapse: a rare entity with an aggressive outcome.

PubMed

Hassan, Masroor; Abdullah, Hafez Mohammad Ammar; Wahid, Abdul; Qamar, Muhammad Ashraf

2018-06-08

Terminal deoxynucleotidyl transferase (TdT)-negative T-cell lymphoblastic lymphoma is a variant of T-cell lymphoblastic lymphoma/T-cell lymphoblastic leukaemia. TdT is a marker of immaturity expressed in 90%-95% cases of lymphoblastic lymphoma and useful in differentiating it from other mature lymphomas/leukaemias. It has been associated with poorer response to chemotherapy and a more aggressive outcome. Here we present a case of TdT-negative T-cell lymphoblastic lymphoma in a 28-year-old man who presented with superior vena cava syndrome. The patient was treated with hyper-cyclophosphamide,vincristine, Adriamycin, dexamethasone (CVAD), however unfortunately suffered a relapse 1 year later. A unique feature of our case was that on relapse, the patient lost expression of the T-cell lineage-specific marker CD3, which has previously not been reported in association with TdT-negative T-cell lymphoblastic lymphoma. The patient failed to respond to chemotherapy on his relapse and died. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Eliminating malignant cells from cryopreserved ovarian tissue is possible in leukaemia patients.

PubMed

Soares, Michelle; Saussoy, Pascale; Maskens, Mathilde; Reul, Hélène; Amorim, Christiani A; Donnez, Jacques; Dolmans, Marie-Madeleine

2017-07-01

Reimplantation of cryopreserved ovarian tissue (OT) can successfully restore ovarian function in young cancer patients after gonadotoxic treatment. However, for patients with leukaemia, there is a risk of malignant cell transmission. Our objective was to evaluate minimal disseminated disease in OT from leukaemia patients and test a follicle isolation technique to obtain disease-free follicle suspensions. Cryopreserved OT from 12 leukaemia patients was thawed and analysed by histology and long-term xenografting in immunosuppressed mice. In 10 patients, follicles were isolated from OT, and polymerase chain reaction (PCR) was performed on tissue, digested ovarian suspensions and isolated follicle suspensions to investigate leukaemic cell presence. Mean patient age was 17·1 years. An average of 3·2 follicles were isolated per mm² of cortex. Xenografting of OT induced leukaemic masses in 2/12 mice. PCR identified leukaemic cell presence in 66% of OT. Malignant cells were also detected in digested ovarian suspensions. However, none of the follicle samples (>2300 follicles tested) showed any malignant cell presence after washing. This study demonstrates that it is possible to recover large numbers of viable follicles from cryopreserved OT of leukaemia patients. All isolated and washed follicle suspensions tested negative for leukaemic cells, giving leukaemia patients genuine hope of fertility restoration. © 2017 John Wiley & Sons Ltd.

Carcinocythaemia (carcinoma cell leukaemia) in a dog: an acute leukaemia-like picture due to metastatic carcinoma.

PubMed

Amati, M; Miele, F; Avallone, G; Banco, B; Bertazzolo, W

2012-08-01

An eight-year-old entire female boxer was presented with a two-week history of anorexia and lethargy and two-day history of unilateral left epistaxis. Clinical findings and laboratory test results suggested disseminated intravascular coagulation. On blood smear evaluation, occasional large epithelioid-like unclassified cells were detected. Occasionally these cells were organised in small clusters. Bone marrow examination revealed a marked infiltration by a malignant population of the same epithelioid-like cells. The dog was euthanased because of the guarded prognosis. Following histology and immunohistochemistry, a widespread undifferentiated carcinoma of unknown primary origin was diagnosed. To the authors' knowledge, this is the first case of carcinoma cell leukaemia reported in a dog. Carcinoma cell leukaemia is a rare oncological condition previously described in humans, characterised by non-haematopoietic neoplastic cells in peripheral blood. © 2012 British Small Animal Veterinary Association.

An immunophenotypic and molecular diagnosis of composite hairy cell leukaemia and chronic lymphocytic leukaemia.

PubMed

Liptrot, Stuart; O' Brien, David; Langabeer, Stephen E; Quinn, Fiona; Mackarel, A Jill; Elder, Patrick; Vandenberghe, Elisabeth; Hayden, Patrick J

2013-12-01

Hairy cell leukaemia (HCL) and chronic lymphocytic leukaemia (CLL) are distinct clinicopathological B cell chronic lymphoproliferative disorders (B-CLPD). Both diseases have characteristic immunophenotypic and molecular features. The co-existence of two B-CLPD is perhaps more common than previously thought but a composite HCL and CLL has been rarely documented. A case is reported in which the morphology, integrated with an extensive immunophenotyping panel, and incorporation of the recently described HCL-associated BRAF V600E mutation, enabled the prompt diagnosis of composite HCL and CLL thus allowing appropriate treatment selection. This case serves to highlight the benefit of a multidisciplinary approach to the diagnosis of bi-clonal B-CLPD.

Dysregulation of haematopoietic stem cell regulatory programs in acute myeloid leukaemia.

PubMed

Basilico, Silvia; Göttgens, Berthold

2017-07-01

Haematopoietic stem cells (HSC) are situated at the apex of the haematopoietic differentiation hierarchy, ensuring the life-long supply of mature haematopoietic cells and forming a reservoir to replenish the haematopoietic system in case of emergency such as acute blood loss. To maintain a balanced production of all mature lineages and at the same time secure a stem cell reservoir, intricate regulatory programs have evolved to control multi-lineage differentiation and self-renewal in haematopoietic stem and progenitor cells (HSPCs). Leukaemogenic mutations commonly disrupt these regulatory programs causing a block in differentiation with simultaneous enhancement of proliferation. Here, we briefly summarize key aspects of HSPC regulatory programs, and then focus on their disruption by leukaemogenic fusion genes containing the mixed lineage leukaemia (MLL) gene. Using MLL as an example, we explore important questions of wider significance that are still under debate, including the importance of cell of origin, to what extent leukaemia oncogenes impose specific regulatory programs and the relevance of leukaemia stem cells for disease development and prognosis. Finally, we suggest that disruption of stem cell regulatory programs is likely to play an important role in many other pathologies including ageing-associated regenerative failure.

Extended diagnostic criteria for plasmacytoid dendritic cell leukaemia.

PubMed

Garnache-Ottou, Francine; Feuillard, Jean; Ferrand, Christophe; Biichle, Sabeha; Trimoreau, Franck; Seilles, Estelle; Salaun, Véronique; Garand, Richard; Lepelley, Pascale; Maynadié, Marc; Kuhlein, Emilienne; Deconinck, Eric; Daliphard, Sylvie; Chaperot, Laurence; Beseggio, Lucille; Foisseaud, Vincent; Macintyre, Elizabeth; Bene, Marie-Christine; Saas, Philippe; Jacob, Marie-Christine

2009-06-01

The diagnosis of plasmacytoid dendritic cell leukaemia (pDCL) is based on the immunophenotypic profile: CD4(+) CD56(+) lineage(neg) CD45RA(+)/RO(neg) CD11c(neg) CD116(low) CD123(+) CD34(neg) CD36(+) HLA-DR(+). Several studies have reported pDCL cases that do not express this exact profile or expressing some lineage antigens that could thus be misdiagnosed. This study aimed to validate pDCL-specific markers for diagnosis by flow-cytometry or quantitative reverse transcription polymerase chain reaction on bone marrow samples. Expression of markers previously found in normal pDC was analysed in 16 pDCL, four pDCL presenting an atypical phenotype (apDCL) and 113 non-pDC - lymphoid or myeloid - acute leukaemia. CD123 was expressed at significantly higher levels in pDCL and apDCL. BDCA-2 was expressed on 12/16 pDCL and on 2/4 apDCL, but was never detected in the 113 non-pDC acute leukaemia cases. BDCA-4 expression was found on 13/16 pDCL, but also in 12% of non-pDC acute leukaemia. High levels of LILRA4 and TCL1A transcripts distinguished pDCL and apDCL from all other acute leukaemia (except B-cell acute lymphoblastic leukaemia for TCL1A). We thus propose a diagnosis strategy, scoring first the CD4(+) CD56(+/-) MPO(neg) cCD3(neg) cCD79a(neg) CD11c(neg) profile and then the CD123(high), BDCA-2 and BDCA-4 expression. Atypical pDCL can be also identified this way and non-pDC acute leukaemia excluded: this scoring strategy is useful for diagnosing pDCL and apDCL.

Erosion of the chronic myeloid leukaemia stem cell pool by PPARγ agonists.

PubMed

Prost, Stéphane; Relouzat, Francis; Spentchian, Marc; Ouzegdouh, Yasmine; Saliba, Joseph; Massonnet, Gérald; Beressi, Jean-Paul; Verhoeyen, Els; Raggueneau, Victoria; Maneglier, Benjamin; Castaigne, Sylvie; Chomienne, Christine; Chrétien, Stany; Rousselot, Philippe; Leboulch, Philippe

2015-09-17

Whether cancer is maintained by a small number of stem cells or is composed of proliferating cells with approximate phenotypic equivalency is a central question in cancer biology. In the stem cell hypothesis, relapse after treatment may occur by failure to eradicate cancer stem cells. Chronic myeloid leukaemia (CML) is quintessential to this hypothesis. CML is a myeloproliferative disorder that results from dysregulated tyrosine kinase activity of the fusion oncoprotein BCR-ABL. During the chronic phase, this sole genetic abnormality (chromosomal translocation Ph(+): t(9;22)(q34;q11)) at the stem cell level causes increased proliferation of myeloid cells without loss of their capacity to differentiate. Without treatment, most patients progress to the blast phase when additional oncogenic mutations result in a fatal acute leukaemia made of proliferating immature cells. Imatinib mesylate and other tyrosine kinase inhibitors (TKIs) that target the kinase activity of BCR-ABL have improved patient survival markedly. However, fewer than 10% of patients reach the stage of complete molecular response (CMR), defined as the point when BCR-ABL transcripts become undetectable in blood cells. Failure to reach CMR results from the inability of TKIs to eradicate quiescent CML leukaemia stem cells (LSCs). Here we show that the residual CML LSC pool can be gradually purged by the glitazones, antidiabetic drugs that are agonists of peroxisome proliferator-activated receptor-γ (PPARγ). We found that activation of PPARγ by the glitazones decreases expression of STAT5 and its downstream targets HIF2α and CITED2, which are key guardians of the quiescence and stemness of CML LSCs. When pioglitazone was given temporarily to three CML patients in chronic residual disease in spite of continuous treatment with imatinib, all of them achieved sustained CMR, up to 4.7 years after withdrawal of pioglitazone. This suggests that clinically relevant cancer eradication may become a generally

Aggressive natural killer (NK)-cell leukaemia and extranodal NK/T-cell lymphoma are two distinct diseases that differ in their clinical presentation and cytogenetic findings.

PubMed

Yang, Ching-Fen; Hsu, Chih-Yi; Ho, Donald M-T

2018-05-01

Aggressive natural killer (NK)-cell leukaemia (ANKCL) and extranodal NK/T-cell lymphoma (ENKTCL) with secondary bone marrow involvement are rare bone marrow NK/T-cell neoplasms and share similar features. This study aimed to distinguish these two entities. We studied bone marrow NK/T-cell neoplasms by classifying them into those with no extramedullary mass (group 1, eight cases) and those with extramedullary mass (group 2, 13 cases). The two groups showed similar clinical presentations and pathological features. Fever and cytopenia were the most common clinical presentations in both groups. The neoplastic cells varied from small and relatively monotonous cells to large pleomorphic cells. In six cases (two in group 1, and four in group 2), the neoplastic infiltrate was inconspicuous, consisting of ≤10% of marrow cells in the interstitium, which were hardly identified by haematoxylin and eosin staining alone. Nearly all patients rapidly died, regardless of the neoplastic infiltrate volume. All of the group 1 patients fulfilled the World Health Organisation 2017 diagnostic criteria of ANKCL, and their survival was significantly worse than that of the group 2 patients (P = 0.035). In addition, there was a significant association between being in group 1 and chromosome 7 abnormalities. Chromosome 6q deletion, which is commonly reported in ENKTCL, was seen in two of our group 2 patients, and was not observed in any of our group 1 patients. ANKCL with no extramedullary mass should be distinguished from ENKTCL with bone marrow involvement, as the former shows distinct outcomes and genetic features. © 2018 John Wiley & Sons Ltd.

Wt-p53 action in human leukaemia cell lines corresponding to different stages of differentiation.

PubMed

Rizzo, M G; Zepparoni, A; Cristofanelli, B; Scardigli, R; Crescenzi, M; Blandino, G; Giuliacci, S; Ferrari, S; Soddu, S; Sacchi, A

1998-05-01

Recent studies support the potential application of the wt-p53 gene in cancer therapy. Expression of exogenous wt-p53 suppresses a variety of leukaemia phenotypes by acting on cell survival, proliferation and/or differentiation. As for tumour gene therapy, the final fate of the neoplastic cells is one of the most relevant points. We examined the effects of exogenous wt-p53 gene expression in several leukaemia cell lines to identify p53-responsive leukaemia. The temperature-sensitive p53Val135 mutant or the human wt-p53 cDNA was transduced in leukaemia cell lines representative of different acute leukaemia FAB subtypes, including M1 (KG1), M2 (HL-60), M3 (NB4), M5 (U937) and M6 (HEL 92.1.7), as well as blast crisis of chronic myelogenous leukaemia (BC-CML: K562, BV173) showing diverse differentiation features. By morphological, molecular and biochemical analyses, we have shown that exogenous wt-p53 gene expression induces apoptosis only in cells corresponding to M1, M2 and M3 of the FAB classification and in BC-CML showing morphological and cytochemical features of undifferentiated blast cells. In contrast, it promotes differentiation in the others. Interestingly, cell responsiveness was independent of the vector used and the status of the endogenous p53 gene.

Folliculotropic T-cell infiltrates associated with B-cell chronic lymphocytic leukaemia or MALT lymphoma may reveal either true mycosis fungoides or pseudolymphomatous reaction: seven cases and review of the literature.

PubMed

Ingen-Housz-Oro, S; Franck, N; Beneton, N; Fauconneau, A; Do-Pham, G; Carlotti, A; Petit, T; Liolios, I; Bara, C; Carpentier, H; Storelli, D; Prophette, B; Garderet, L; Haioun, C; Petit, E; Delfau-Larue, M-H; Vergier, B; Chosidow, O; Beylot-Barry, M; Ortonne, N

2015-01-01

Mycosis fungoides (MF) and pseudo-MF (or MF simulant) can be associated with B-cell malignancies, but distinction between a true neoplasm and a reactive process may be difficult. To report seven patients with B-cell malignancy and folliculotropic MF or pseudo-MF and emphasize on criteria allowing distinction between the two conditions. We retrospectively and prospectively included seven patients with B-cell malignancy who presented skin lesions histologically consisting in a folliculotropic T-cell infiltrate and reviewed the literature on the topic. Four men and three women had a chronic lymphocytic leukaemia (n = 6) or a MALT-type lymphoma (n = 1). Five patients had localized papules, and two had patches and plaques. Histological examination showed in all cases a diffuse dermal T-cell infiltrate with folliculotropic involvement and follicular mucinosis associated with clusters of the B-cell lymphoma, without significant expression of follicular helper T-cell markers. T-cell rearrangement studies showed a polyclonal pattern in the patients with papules and a monoclonal pattern in the cases of patches and plaques. Papular lesions had an indolent evolution, whereas patches and plaques persisted or worsened into transformed MF. Folliculotropic T-cell infiltrates associated with B-cell malignancies can be either a true folliculotropic MF or a pseudo-MF. The distinction between both conditions cannot rely only on the histopathological aspect, but needs both a clinical pathological correlation and the search for a dominant T-cell clone. Whether the neoplastic T and B cells derive from a common ancestor or the T-cell proliferation is promoted by the underlying B-cell lymphoma remains unsolved, but interaction between B and T cell in the skin does not appear to be dependent on a TFH differentiation of the T-cell infiltrate. © 2014 European Academy of Dermatology and Venereology.

Severe asymptomatic hypophosphataemia in a child with T-acute lymphoblastic leukaemia.

PubMed

Zakaria, N H; Sthaneshwar, P; Shanmugam, H

2017-12-01

Hypophosphataemia is a metabolic disorder that is commonly encountered in critically ill patients. Phosphate has many roles in physiological functions, thus the depletion of serum phosphate could lead to impairment in multiple organ systems, which include the respiratory, cardiovascular, neurological and muscular systems and haematological and metabolic functions. Hypophosphataemia is defined as plasma phosphate level below 0.80 mmol per litre (mmol/L) and can be further divided into subgroups of mild (plasma phosphate of 0.66 to 0.79 mmol/L), moderate (plasma phosphate of 0.32 to 0.65 mmol/L) and severe (plasma phosphate of less than 0.32 mmol/L). The causes of hypophosphataemia include inadequate phosphate intake, decreased intestinal absorption, gastrointestinal or renal phosphate loss, and redistribution of phosphate into cells. Symptomatic hypophosphataemia associated with haematological malignancies has been reported infrequently. We report here a case of asymptomatic severe hypophosphataemia in a child with acute T-cell lymphoblastic leukaemia. A 14-year-old Chinese boy was diagnosed to have acute T cell lymphoblastic leukaemia (ALL). His serum biochemistry results were normal except inorganic phosphate and lactate dehydrogenase levels. The serum inorganic phosphate level was 0.1mmol/L and the level was low on repeated analysis. The child had no symptoms related to low phosphate levels. The possible causes of low phosphate were ruled out and urine Tmp/GFR was normal. Chemotherapy regime was started and the serum phosphate levels started to increase. Hypophosphataemia in leukaemia was attributed to shift of phosphorus into leukemic cells and excessive cellular phosphate consumption by rapidly proliferating cells. Several reports of symptomatic hypophosphataemia in myelogenous and lymphoblastic leukaemia in adults have been reported. To our knowledge this is the first case of severe asymptomatic hypophosphataemia in a child with ALL.

Cell markers in the recognition of acute myeloblastic leukaemia subtypes.

PubMed

Andoljsek, Dusan; Preloznik Zupan, Irena; Zontar, Darja; Cernelc, Peter; Mlakar, Uros; Modic, Mojca; Pretnar, Joze; Zver, Samo

2002-01-01

The diagnosis of acute myeloblastic leukaemia (AML) is based on cell morphology, cytogenetic and molecular changes, cell markers and clinical data. Our aim was to establish whether morphology and cell markers are comparable in the evaluation of AML. Bone marrow smears were analysed, and flow cytometry and monoclonal antibodies were used to determine cell type and maturity. Morphology and cell markers correlated differently in different AML subtypes.

Feedback regulation in a stem cell model with acute myeloid leukaemia.

PubMed

Jiao, Jianfeng; Luo, Min; Wang, Ruiqi

2018-04-24

The haematopoietic lineages with leukaemia lineages are considered in this paper. In particular, we mainly consider that haematopoietic lineages are tightly controlled by negative feedback inhibition of end-product. Actually, leukemia has been found 100 years ago. Up to now, the exact mechanism is still unknown, and many factors are thought to be associated with the pathogenesis of leukemia. Nevertheless, it is very necessary to continue the profound study of the pathogenesis of leukemia. Here, we propose a new mathematical model which include some negative feedback inhibition from the terminally differentiated cells of haematopoietic lineages to the haematopoietic stem cells and haematopoietic progenitor cells in order to describe the regulatory mechanisms mentioned above by a set of ordinary differential equations. Afterwards, we carried out detailed dynamical bifurcation analysis of the model, and obtained some meaningful results. In this work, we mainly perform the analysis of the mathematic model by bifurcation theory and numerical simulations. We have not only incorporated some new negative feedback mechanisms to the existing model, but also constructed our own model by using the modeling method of stem cell theory with probability method. Through a series of qualitative analysis and numerical simulations, we obtain that the weak negative feedback for differentiation probability is conducive to the cure of leukemia. However, with the strengthening of negative feedback, leukemia will be more difficult to be cured, and even induce death. In contrast, strong negative feedback for differentiation rate of progenitor cells can promote healthy haematopoiesis and suppress leukaemia. These results demonstrate that healthy progenitor cells are bestowed a competitive advantage over leukaemia stem cells. Weak g 1 , g 2 , and h 1 enable the system stays in the healthy state. However, strong h 2 can promote healthy haematopoiesis and suppress leukaemia.

Clinical significance of early T-cell precursor acute lymphoblastic leukaemia: results of the Tokyo Children's Cancer Study Group Study L99-15.

PubMed

Inukai, Takeshi; Kiyokawa, Nobutaka; Campana, Dario; Coustan-Smith, Elaine; Kikuchi, Akira; Kobayashi, Miyuki; Takahashi, Hiroyuki; Koh, Katsuyoshi; Manabe, Atsushi; Kumagai, Masaaki; Ikuta, Koichiro; Hayashi, Yasuhide; Tsuchida, Masahiro; Sugita, Kanji; Ohara, Akira

2012-02-01

Early T-cell precursor acute lymphoblastic leukaemia (ETP-ALL) is a recently identified subtype of T-ALL with distinctive gene expression and cell marker profiles, poor response to chemotherapy and a very high risk of relapse. We determined the reliability of restricted panel of cell markers to identify EPT-ALL using a previously classified cohort. Then, we applied the cell marker profile that best discriminated ETP-ALL to a cohort of 91 patients with T-ALL enrolled in the Tokyo Children's Cancer Study Group L99-15 study, which included allogeneic stem cell transplantation (allo-SCT) for patients with poor prednisone response. Five of the 91 patients (5·5%) met the ETP-ALL criteria. There were no significant differences in presenting clinical features between these and the remaining 86 patients. Response to early remission induction therapy was inferior in ETP-ALL as compared with T-ALL. The ETP-ALL subgroup showed a significantly poorer event-free survival (4-year rate; 40%) than the T-ALL subgroup (70%, P=0·014). Of note, three of four relapsed ETP-ALL patients survived after allo-SCT, indicating that allo-SCT can be effective for this drug-resistant subtype of T-ALL. © 2011 Blackwell Publishing Ltd.

Primary angiocentric/angioinvasive T-cell lymphoma of the tympanic bulla in a feline leukaemia virus-positive cat.

PubMed

Santagostino, Sara F; Mortellaro, Carlo M; Buchholz, Julia; Lugli, Margherita; Forlani, Annalisa; Ghisleni, Gabriele; Roccabianca, Paola

2015-01-01

Case summary A 5-year-old neutered female feline leukaemia virus (FeLV)-positive domestic shorthair cat with a 5 month history of otitis media was referred for head tilt, stertor and dyspnoea. Computed tomography scan revealed soft tissue opacities inside the right tympanic bulla, with bone remodelling, and concurrent nasopharyngeal and intracranial invasion. Endoscopically guided bioptic samples were collected from the nasopharynx and middle ear. Histology revealed dense sheets of round, large, neoplastic cells, often surrounding or invading vascular walls. Neoplastic cells expressed CD3, FeLV p27 and gp70 antigens. A middle ear angiocentric/angioinvasive T-cell lymphoma was diagnosed. After improvement of clinical conditions following radiation therapy, the cat died unexpectedly. At necropsy, hepatic and splenic spread was detected. Relevance and novel information Primary middle ear tumours are rare and their diagnosis is often delayed as clinical signs mimic more common otological conditions. Multiple bioptic specimens are pivotal for a definitive diagnosis. The young age of the cat, serology and immunohistochemistry revealed a possible transforming role of FeLV.

HOXA9 is critical in the proliferation, differentiation, and malignancy of leukaemia cells both in vitro and in vivo.

PubMed

Chen, Shibing; Yu, Juan; Lv, Xin; Zhang, Lijuan

2017-10-01

Progress in the understanding of the molecular mechanism for acute myeloid leukaemia is of great significance to generate new potential targets for treatment. Recent studies showed that HOXA9, a homeodomain-containing transcription factor, is commonly deregulated in acute leukaemia. In this study, we elucidated the direct correlation between HoxA9 expression and progression of leukaemia using 2 different types of leukaemia cells HL-60 and MOLT-3. The HoxA9 expression level was decreased in leukaemia cells with the treatment of all-trans retinoic acid or arsenic trioxide (As 2 O 3 ). Downregulation of HoxA9 could impair the proliferation and promote the leukaemia cell death. HoxA9 silencing also potentiated the differentiation of leukaemia cells, and in vivo studies demonstrated that HoxA9 downregulation could interfere the tumour growth. Interestingly, HoxA9 silencing also led to the alteration in miRNA expression, mediating the promoting effect on the leukaemia cell differentiation. Therefore, this work provided a promising and potentially efficient target to leukaemia treatment, indicating that HoxA9 is likely to be an ideal candidate in the gene therapy against acute myeloid leukaemia. In this study, we elucidated the critical role of HoxA9 in the proliferation and differentiation of leukaemia cells both in vitro and in vivo. The effect of HoxA9 modulation was correlated with the clinical effect of all-trans retinoic acid and As 2 O 3 . Furthermore, HoxA9 also regulated the miRNA expression, controlling the leukaemia cell differentiation. Therefore, this work provided new insights into molecular mechanism underlying the leukaemia treatment, potentially putting forward a brand new target to the gene therapy against leukaemia. Copyright © 2017 John Wiley & Sons, Ltd.

Effects of FR235222, a novel HDAC inhibitor, in proliferation and apoptosis of human leukaemia cell lines: role of annexin A1.

PubMed

Petrella, Antonello; D'Acunto, Cosimo Walter; Rodriquez, Manuela; Festa, Michela; Tosco, Alessandra; Bruno, Ines; Terracciano, Stefania; Taddei, Maurizio; Paloma, Luigi Gomez; Parente, Luca

2008-03-01

FR235222, a novel histone deacetylase inhibitor (HDACi), at 50nM caused accumulation of acetylated histone H4, inhibition of cell proliferation and G1 cycle arrest accompanied by increase of p21 and down-regulation of cyclin E in human promyelocytic leukaemia U937 cells. The compound was also able to increase the protein and mRNA levels of annexin A1 (ANXA1) without effects on apoptosis. Similar effects were observed in human chronic myelogenous leukaemia K562 cells and human T cell leukaemia Jurkat cells. Cycle arrest and ANXA1 expression, without significant effects on apoptosis, were also induced by different HDACi like suberoylanilide hydroxamic acid (SAHA) and trichostatin-A (TSA). FR235222 at 0.5 microM stimulated apoptosis of all leukaemia cell lines associated to an increased expression of the full-length (37kDa) protein and the appearance of a 33kDa N-terminal cleavage product in both cytosol and membrane. These results suggest that ANXA1 expression may mediate cycle arrest induced by low doses FR235222, whereas apoptosis induced by high doses FR235222 is associated to ANXA1 processing.

Leukaemia cell of origin identified by chromatin landscape of bulk tumour cells

PubMed Central

George, Joshy; Uyar, Asli; Young, Kira; Kuffler, Lauren; Waldron-Francis, Kaiden; Marquez, Eladio; Ucar, Duygu; Trowbridge, Jennifer J.

2016-01-01

The precise identity of a tumour's cell of origin can influence disease prognosis and outcome. Methods to reliably define tumour cell of origin from primary, bulk tumour cell samples has been a challenge. Here we use a well-defined model of MLL-rearranged acute myeloid leukaemia (AML) to demonstrate that transforming haematopoietic stem cells (HSCs) and multipotent progenitors results in more aggressive AML than transforming committed progenitor cells. Transcriptome profiling reveals a gene expression signature broadly distinguishing stem cell-derived versus progenitor cell-derived AML, including genes involved in immune escape, extravasation and small GTPase signal transduction. However, whole-genome profiling of open chromatin reveals precise and robust biomarkers reflecting each cell of origin tested, from bulk AML tumour cell sampling. We find that bulk AML tumour cells exhibit distinct open chromatin loci that reflect the transformed cell of origin and suggest that open chromatin patterns may be leveraged as prognostic signatures in human AML. PMID:27397025

Abundant and equipotent founder cells establish and maintain acute lymphoblastic leukaemia.

PubMed

Elder, A; Bomken, S; Wilson, I; Blair, H J; Cockell, S; Ponthan, F; Dormon, K; Pal, D; Heidenreich, O; Vormoor, J

2017-12-01

High frequencies of blasts in primary acute lymphoblastic leukaemia (ALL) samples have the potential to induce leukaemia and to engraft mice. However, it is unclear how individual ALL cells each contribute to drive leukaemic development in a bulk transplant and the extent to which these blasts vary functionally. We used cellular barcoding as a fate mapping tool to track primograft ALL blasts in vivo. Our results show that high numbers of ALL founder cells contribute at similar frequencies to leukaemic propagation over serial transplants, without any clear evidence of clonal succession. These founder cells also exhibit equal capacity to home and engraft to different organs, although stochastic processes may alter the composition in restrictive niches. Our findings enhance the stochastic stem cell model of ALL by demonstrating equal functional abilities of singular ALL blasts and show that successful treatment strategies must eradicate the entire leukaemic cell population.

Dietary Phenolic Acids Act as Effective Antioxidants in Membrane Models and in Cultured Cells, Exhibiting Proapoptotic Effects in Leukaemia Cells

PubMed Central

Zambonin, Laura; Caliceti, Cristiana; Vieceli Dalla Sega, Francesco; Fiorentini, Diana; Hrelia, Silvana; Landi, Laura; Prata, Cecilia

2012-01-01

Caffeic, syringic, and protocatechuic acids are phenolic acids derived directly from food intake or come from the gut metabolism of polyphenols. In this study, the antioxidant activity of these compounds was at first evaluated in membrane models, where caffeic acid behaved as a very effective chain-breaking antioxidant, whereas syringic and protocatechuic acids were only retardants of lipid peroxidation. However, all three compounds acted as good scavengers of reactive species in cultured cells subjected to exogenous oxidative stress produced by low level of H2O2. Many tumour cells are characterised by increased ROS levels compared with their noncancerous counterparts. Therefore, we investigated whether phenolic acids, at low concentrations, comparable to those present in human plasma, were able to decrease basal reactive species. Results show that phenolic acids reduced ROS in a leukaemia cell line (HEL), whereas no effect was observed in normal cells, such as HUVEC. The compounds exhibited no toxicity to normal cells while they decreased proliferation in leukaemia cells, inducing apoptosis. In the debate on optimal ROS-manipulating strategies in cancer therapy, our work in leukaemia cells supports the antioxidant ROS-depleting approach. PMID:22792417

Crystalline inclusions in the cytoplasm and nuclei of cells of acute myeloid leukaemia.

PubMed

Pearson, E C

1989-01-01

In a survey by electron microscopy of peripheral blood and/or bone marrow from 230 adult patients with acute myeloid leukaemia, five were observed to contain crystalline inclusions in the cytoplasm of the leukaemic cells and a sixth contained crystals in the nuclei. In four cases, two of FAB type M2 and two of M4, the cytoplasmic crystals were hexagonal in section and 1-2 micron long. Two examples showed internal periodicities in the range 3.3-4.0 nm when the electronmicrographs were analysed by optical diffractometry. A single case of M1 contained smaller trapezoidal crystals with a 4.9nm periodicity. The sixth patient, with unusual cytological abnormalities and a rare t(3; 6) chromosomal translocation, contained six-sided crystals in the nuclei of some relatively undifferentiated cells. To the best of our knowledge such intranuclear crystals have not previously been reported in leukaemia. The relevance of the crystals to the leukaemic process is discussed.

Critical stoichiometric ratio of CD4(+)  CD25(+)  FoxP3(+) regulatory T cells and CD4(+)  CD25(-) responder T cells influence immunosuppression in patients with B-cell acute lymphoblastic leukaemia.

PubMed

Bhattacharya, Kaushik; Chandra, Sarmila; Mandal, Chitra

2014-05-01

Regulatory T (Treg) cells act to suppress activation of the immune system and thereby maintain immunological homeostasis and tolerance to self-antigens. The frequency and suppressing activity of Treg cells in general are high in different malignancies. We wanted to identify the role and regulation of CD4(+)  CD25(+)  FoxP3(+) Treg cells in B-cell acute lymphoblastic leukaemia (B-ALL). We have included patients at diagnosis (n = 54), patients in clinical remission (n = 32) and normal healthy individuals (n = 35). These diagnosed patients demonstrated a lower number of CD4(+)  CD25(+) cells co-expressing a higher level of FoxP3, interleukin-10, transforming growth factor-β and CD152/CTLA-4 than the normal population. Treg cells from patients showed a higher suppressive capability on CD4(+)  CD25(-) responder T (Tresp) cells than normal. The frequency and immunosuppressive potential of CD4(+)  CD25(+)  FoxP3(+) Treg cells became high with the progression of malignancy in B-ALL. Relative distribution of Tresp and Treg cells was only ~5 : 1 in B-ALL but ~35 : 1 in normal healthy individuals, further confirming the elevated immunosuppression in patients. A co-culture study at these definite ex vivo ratios, indicated that Treg cells from B-ALL patients exhibited higher immunosuppression than Treg cells from normal healthy individuals. After chemotherapy using the MCP841 protocol, the frequency of CD4(+)  CD25(+) cells was gradually enhanced with the reduction of FoxP3, interleukin-10 positivity corresponded with disease presentation, indicating reduced immunosuppression. Taken together, our study indicated that the CD4(+)  CD25(+)  FoxP3(+) Treg cells played an important role in immunosuppression, resulting in a positive disease-correlation in these patients. To the best of our knowledge, this is the first detailed report on the frequency, regulation and functionality of Treg cells in B-ALL. © 2013 John Wiley & Sons Ltd.

RUNX3 promoter hypermethylation is frequent in leukaemia cell lines and associated with acute myeloid leukaemia inv(16) subtype.

PubMed

Estécio, Marcos R H; Maddipoti, Sirisha; Bueso-Ramos, Carlos; DiNardo, Courtney D; Yang, Hui; Wei, Yue; Kondo, Kimie; Fang, Zhihong; Stevenson, William; Chang, Kun-Sang; Pierce, Sherry A; Bohannan, Zachary; Borthakur, Gautam; Kantarjian, Hagop; Garcia-Manero, Guillermo

2015-05-01

Correlative and functional studies support the involvement of the RUNX gene family in haematological malignancies. To elucidate the role of epigenetics in RUNX inactivation, we evaluated promoter DNA methylation of RUNX1, 2, and 3 in 23 leukaemia cell lines and samples from acute myeloid leukaemia (AML), acute lymphocytic leukaemia (ALL) and myelodysplatic syndromes (MDS) patients. RUNX1 and RUNX2 gene promoters were mostly unmethylated in cell lines and clinical samples. Hypermethylation of RUNX3 was frequent among cell lines (74%) and highly variable among patient samples, with clear association to cytogenetic status. High frequency of RUNX3 hypermethylation (85% of the 20 studied cases) was found in AML patients with inv(16)(p13.1q22) compared to other AML subtypes (31% of the other 49 cases). RUNX3 hypermethylation was also frequent in ALL (100% of the six cases) but low in MDS (21%). In support of a functional role, hypermethylation of RUNX3 was correlated with low levels of protein, and treatment of cell lines with the DNA demethylating agent, decitabine, resulted in mRNA re-expression. Furthermore, relapse-free survival of non-inv(16)(p13.1q22) AML patients without RUNX3 methylation was significantly better (P = 0·016) than that of methylated cases. These results suggest that RUNX3 silencing is an important event in inv(16)(p13.1q22) leukaemias. © 2015 John Wiley & Sons Ltd.

Bone marrow and splenic histology in hairy cell leukaemia.

PubMed

Wotherspoon, Andrew; Attygalle, Ayoma; Mendes, Larissa Sena Teixeira

2015-12-01

Hairy cell leukaemia is a rare chronic neoplastic B-cell lymphoproliferation that characteristically involves blood, bone marrow and spleen with liver, lymph node and skin less commonly involved. Histologically, the cells have a characteristic appearance with pale/clear cytoplasm and round or reniform nuclei. In the spleen, the infiltrate involves the red pulp and is frequently associated with areas of haemorrhage (blood lakes). The cells stain for B-cell related antigens as well as with antibodies against tartrate-resistant acid phosphatase, DBA44 (CD72), CD11c, CD25, CD103, CD123, cyclin D1 and annexin A1. Mutation of BRAF -V600E is present and antibody to the mutant protein can be used as a specific marker. Bone marrow biopsy is essential in the initial assessment of disease as the bone marrow may be inaspirable or unrepresentative of degree of marrow infiltration as a result of the tumour associated fibrosis preventing aspiration of the tumour cell component. Bone marrow biopsy is important in the assessment of therapy response but in this context staining for CD11c and Annexin A1 is not helpful as they are also markers of myeloid lineage and identification of low level infiltration may be obscured. In this context staining for CD20 may be used in conjunction with morphological assessment and staining of serial sections for cyclin D1 and DBA44 to identify subtle residual infiltration. Staining for CD79a and CD19 is not recommended as these antibodies will identify plasma cells and can lead to over-estimation of disease. Staining for CD20 should not be used in patients following with anti-CD20 based treatments. Down regulation of cyclin D1 and CD25 has been reported in patients following BRAF inhibitor therapy and assessment of these antigens should not be used in this context. Histologically, hairy cell leukaemia needs to be distinguished from other B-cell lymphoproliferations associated with splenomegaly including splenic marginal zone lymphoma, splenic

Disruption of TET2 promotes the therapeutic efficacy of CD19-targeted T cells.

PubMed

Fraietta, Joseph A; Nobles, Christopher L; Sammons, Morgan A; Lundh, Stefan; Carty, Shannon A; Reich, Tyler J; Cogdill, Alexandria P; Morrissette, Jennifer J D; DeNizio, Jamie E; Reddy, Shantan; Hwang, Young; Gohil, Mercy; Kulikovskaya, Irina; Nazimuddin, Farzana; Gupta, Minnal; Chen, Fang; Everett, John K; Alexander, Katherine A; Lin-Shiao, Enrique; Gee, Marvin H; Liu, Xiaojun; Young, Regina M; Ambrose, David; Wang, Yan; Xu, Jun; Jordan, Martha S; Marcucci, Katherine T; Levine, Bruce L; Garcia, K Christopher; Zhao, Yangbing; Kalos, Michael; Porter, David L; Kohli, Rahul M; Lacey, Simon F; Berger, Shelley L; Bushman, Frederic D; June, Carl H; Melenhorst, J Joseph

2018-06-01

Cancer immunotherapy based on genetically redirecting T cells has been used successfully to treat B cell malignancies 1-3 . In this strategy, the T cell genome is modified by integration of viral vectors or transposons encoding chimaeric antigen receptors (CARs) that direct tumour cell killing. However, this approach is often limited by the extent of expansion and persistence of CAR T cells 4,5 . Here we report mechanistic insights from studies of a patient with chronic lymphocytic leukaemia treated with CAR T cells targeting the CD19 protein. Following infusion of CAR T cells, anti-tumour activity was evident in the peripheral blood, lymph nodes and bone marrow; this activity was accompanied by complete remission. Unexpectedly, at the peak of the response, 94% of CAR T cells originated from a single clone in which lentiviral vector-mediated insertion of the CAR transgene disrupted the methylcytosine dioxygenase TET2 gene. Further analysis revealed a hypomorphic mutation in this patient's second TET2 allele. TET2-disrupted CAR T cells exhibited an epigenetic profile consistent with altered T cell differentiation and, at the peak of expansion, displayed a central memory phenotype. Experimental knockdown of TET2 recapitulated the potency-enhancing effect of TET2 dysfunction in this patient's CAR T cells. These findings suggest that the progeny of a single CAR T cell induced leukaemia remission and that TET2 modification may be useful for improving immunotherapies.

The metabolic perturbators metformin, phenformin and AICAR interfere with the growth and survival of murine PTEN-deficient T cell lymphomas and human T-ALL/T-LL cancer cells.

PubMed

Rosilio, Célia; Lounnas, Nadia; Nebout, Marielle; Imbert, Véronique; Hagenbeek, Thijs; Spits, Hergen; Asnafi, Vahid; Pontier-Bres, Rodolphe; Reverso, Julie; Michiels, Jean-François; Sahra, Issam Ben; Bost, Fréderic; Peyron, Jean-François

2013-08-09

We show here that the antidiabetic agents metformin and phenformin and the AMPK activator AICAR exert strong anti-tumoural effects on tPTEN-/- lymphoma cells and on human T-ALL cell lines and primary samples. The compounds act by inhibiting tumour metabolism and proliferation and by inducing apoptosis in parallel with an activation of AMPK and an inhibition of constitutive mTOR. In tPTEN-/- cells, the drugs potentiated the anti-leukaemic effects of dexamethasone, and metformin and phenformin synergised with 2-deoxyglucose (2DG) to impair tumour cell survival. In vivo, metformin and AICAR strongly decreased the growth of luciferase-expressing tPTEN-/- cells xenografted in Nude mice, demonstrating that metabolism targeting could be a potent adjuvant strategy for lymphoma/leukaemia treatment. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Immunocytochemical markers in acute leukaemias diagnosis.

PubMed

Gluzman, D F; Nadgornaya, V A; Sklyarenko, L M; Ivanovskaya, T S; Poludnenko, L Yu; Ukrainskaya, N I

2010-09-01

The study included 1742 patients with acute myeloblastic leukaemias (AML) and acute lymphoblastic leukaemias (ALL), Kyiv city residents and patients from 20 regions of Ukraine. Bone marrow and blood smears were sent at diagnosis to Reference Center. The analysis was based on May-Grünvald-Giemza (MGG) stain and cytochemical reactions (MPO, acNSE, CAE, AP, PAS). Immunocytochemical techniques (APAAP, LSAB) and broad panel of monoclonal antibodies (MoAbs) against lineage specific and differentiation antigens of leukocytes were employed for immunophenotyping of leukemic blast cells directly in blood and bone marrow smears. Different types of AML were defined by the expression of the cell surface and cytoplasmic antigens. Immunocytochemical study was required especially in diagnosing of AML with minimal differentiation, acute megakaryoblastic leukaemia, acute erythroid leukaemia and acute leukaemias of ambiguous lineage. Acute lymphoblastic leukaemias was broadly classified into B-lineage and T-lineage ALL. According to the degree of B-lymphoid differentiation of the blast cells four subtypes of B-lineage ALL were established. T-lineage ALL observed in patients were also divided into four subtypes. Immunocytochemical examination was required to diagnose AL of ambiguous lineage with no clear evidence of lineage differentiation (acute undifferentiated leukaemia) or those with blasts that express markers of more than one lineage (mixed phenotype acute leukaemias).

MYD88 Inhibitor ST2825 Suppresses the Growth of Lymphoma and Leukaemia Cells.

PubMed

Shiratori, Erika; Itoh, Mai; Tohda, Shuji

2017-11-01

Myeloid differentiation primary response gene 88 (MYD88), which activates the nuclear factor kappa B (NF-κB) pathway, is important for the growth of lymphoma and leukaemia cells. In this study, we investigated the effects of ST2825, a synthetic peptidomimetic compound which inhibits MYD88 homodimerization, on their growth. Seven lymphoma and leukaemia cell lines including TMD8, a B-cell lymphoma line with MYD88-activating mutation, were treated with ST2825 and analysed for cell proliferation and expression of NF-κB signalling-related molecules. ST2825 suppressed the growth of all cell lines by inducing apoptosis and down-regulating phosphorylation of NF-κB pathway components inhibitor of nuclear factor kappa B kinase (IκB) and reticuloendotheliosis oncogene A (RelA), as well as of MYD88 activator Bruton tyrosine kinase (BTK), suggesting that MYD88 may affect BTK activity. ST2825 effects were specific as MYD88-targeting siRNA also suppressed phosphorylation of NF-κB signalling proteins and BTK in TMD8 cells. ST2825 may be a novel drug targeting not only B-lymphoid malignancies with MYD88 mutations, but also lymphoma and leukaemia with wild-type MYD88. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Prolonging microtubule dysruption enhances the immunogenicity of chronic lymphocytic leukaemia cells

PubMed Central

Shaha, S P; Tomic, J; Shi, Y; Pham, T; Mero, P; White, D; He, L; Baryza, J L; Wender, P A; Booth, J W; Spaner, D E

2009-01-01

Cytotoxic chemotherapies do not usually mediate the expression of an immunogenic gene programme in tumours, despite activating many of the signalling pathways employed by highly immunogenic cells. Concomitant use of agents that modulate and complement stress-signalling pathways activated by chemotherapeutic agents may then enhance the immunogenicity of cancer cells, increase their susceptibility to T cell-mediated controls and lead to higher clinical remission rates. Consistent with this hypothesis, the microtubule inhibitor, vincristine, caused chronic lymphocytic leukaemia (CLL) cells to die rapidly, without increasing their immunogenicity. Protein kinase C (PKC) agonists (such as bryostatin) delayed the death of vincristine-treated CLL cells and made them highly immunogenic, with increased stimulatory abilities in mixed lymphocyte responses, production of proinflammatory cytokines, expression of co-stimulatory molecules and activation of c-Jun N-terminal kinase (JNK), p38 and nuclear factor kappa B (NF-κB) signalling pathways. This phenotype was similar to the result of activating CLL cells through Toll-like receptors (TLRs), which communicate ‘danger’ signals from infectious pathogens. Use of PKC agonists and microtubule inhibitors to mimic TLR-signalling, and increase the immunogenicity of CLL cells, has implications for the design of chemo-immunotherapeutic strategies. PMID:19737143

Methylenetetrahydrofolate reductase C677T genetic polymorphisms and risk of leukaemia among the North Indian population.

PubMed

Hussain, Syed Rizwan; Naqvi, Hena; Raza, Syed Tasleem; Ahmed, Faisal; Babu, Sunil G; Kumar, Ashutosh; Zaidi, Zeashan Haider; Mahdi, Farzana

2012-08-01

Leukaemia is a heterogeneous disease in which haematopoietic progenitor cells acquire genetic lesions that lead to a block in differentiation, increased self-renewal, and unregulated proliferation. The enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR), involved in folate metabolism, plays a crucial role in cells because folate availability is important for DNA integrity. The aim of this case-control study was to evaluate the association of the C677T MTHFR gene polymorphism with acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL), chronic myeloid leukaemia (CML) and chronic lymphocytic leukaemia (CLL). A total of 275 leukaemia cases - including AML (n = 112), ALL (n = 81), CML (n = 43), CLL (n = 39) - and 251 age/sex-matched healthy control individuals participated in this study. MTHFR C677T polymorphisms in the cases and controls were evaluated by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). The average MTHFR 677CC, 677CT, 677TT genotype frequencies of total leukaemia cases were 68.73%, 19.64%, and 11.64% in cases, and 71.71%, 24.30%, and 3.98% in healthy controls, respectively. The average frequency of the MTHFR 677T allele was 21.45% among the cases compared to 16.13% among the controls. In the present case-control study we have observed a higher frequency of the MTHFR 677TT genotype in cases of leukaemia (AML, ALL, CML and CLL) as compared with controls; this might be due to ethnic and geographic variation. As per our findings, although the frequency of the MTHFR 677T allele is moderately high in AML, ALL and CLL, no statistically significant association was found; on the other hand statistically significant association was found in the context of CML cases. Copyright © 2012 Elsevier Ltd. All rights reserved.

Quercus Suber L. Cork Extracts Induce Apoptosis in Human Myeloid Leukaemia HL-60 Cells.

PubMed

Bejarano, Ignacio; Godoy-Cancho, Belén; Franco, Lourdes; Martínez-Cañas, Manuel A; Tormo, María A

2015-08-01

Quercus suber L. cork contains a diversity of phenolic compounds, mostly low molecular weight phenols. A rising number of reports support with convergent findings that polyphenols evoke pro-apoptotic events in cancerous cells. However, the literature related to the anti-cancer bioactivity of Q. suber L. cork extractives (QSE) is still limited. Herein, we aim to describe the antitumor potential displayed by cork extractives obtained by different extraction methods in the human promyelocytic leukaemia cells. In order to quantify the effects of QSE on cancer cells viability, phosphatidylserine exposure, caspase-3 activity, mitochondrial membrane potential and cell cycle were evaluated. The results indicated that the QSE present a time-dependent and dose-dependent cytotoxicity in the human promyelocytic leukaemia cells. Such a noxious effect leads these leukaemia cells to their death through apoptotic processes by altering the mitochondrial outer membrane potential, activating caspase-3 and externalizing phosphatidylserine. However, cells cycle progression was not affected by the treatments. This study contributes to open a new way to use this natural resource by exploiting its anti-cancer properties. Moreover, it opens new possibilities of application of cork by-products, being more efficient in the sector of cork-based agriculture. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Response to 5-azacytidine in a patient with TET2-mutated angioimmunoblastic T-cell lymphoma and chronic myelomonocytic leukaemia preceded by an EBV-positive large B-cell lymphoma.

PubMed

Saillard, Colombe; Guermouche, Helene; Derrieux, Coralie; Bruneau, Julie; Frenzel, Laurent; Couronne, Lucile; Asnafi, Vahid; Macintyre, Elizabeth; Trinquand, Amélie; Lhermitte, Ludovic; Molina, Thierry; Suarez, Felipe; Lemonnier, Francois; Kosmider, Olivier; Delarue, Richard; Hermine, Olivier; Cheminant, Morgane

2017-12-01

We report the case of a patient with a history of Epstein-Barr virus-positive large B-cell lymphoma, who relapsed with an angioimmunoblastic T-cell lymphoma (AITL) associated with a chronic myelomonocytic leukaemia (CMML). We performed targeted next-generation sequencing on CMML and AITL DNA, which revealed mutations of TET2, DNMT3A, SRSF2, NRAS and IDH1, thus confirming that the spectrum of AITL mutations share similarities with myeloid disorders. The frequencies of TET2/DNMT3A and SRSF2 variants could support the hypothesis that TET2/DNMT3A mutations occurred in an early progenitor cell, which later progressed to both the AITL and CMML clones. Treatment with 5-azacytidine led to the complete remission of both diseases. Thus, targeting DNA methylation abnormalities in AITL may be an alternative strategy to chemotherapy. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Mechanism of DNA-binding enhancement by the human T-cell leukaemia virus transactivator Tax.

PubMed

Baranger, A M; Palmer, C R; Hamm, M K; Giebler, H A; Brauweiler, A; Nyborg, J K; Schepartz, A

1995-08-17

Tax protein activates transcription of the human T-cell leukaemia virus type I (HTLV-I) genome through three imperfect cyclic AMP-responsive element (CRE) target sites located within the viral promoter. Previous work has shown that Tax interacts with the bZIP element of proteins that bind the CRE target site to promote peptide dimerization, suggesting an association between Tax and bZIP coiled coil. Here we show that the site of interaction with Tax is not the coiled coil, but the basic segment. This interaction increases the stability of the GCN4 bZIP dimer by 1.7 kcal mol-1 and the DNA affinity of the dimer by 1.9 kcal mol-1. The differential effect of Tax on several bZip-DNA complexes that differ in peptide sequence or DNA conformation suggests a model for Tax action based on stabilization of a distinct DNA-bound protein structure. This model may explain how Tax interacts with transcription factors of considerable sequence diversity to alter patterns of gene expression.

Carnitine prevents the early mitochondrial damage induced by methylglyoxal bis(guanylhydrazone) in L1210 leukaemia cells.

PubMed

Nikula, P; Ruohola, H; Alhonen-Hongisto, L; Jänne, J

1985-06-01

We previously found that the anti-cancer drug methylglyoxal bis(guanylhydrazone) (mitoguazone) depresses carnitine-dependent oxidation of long-chain fatty acids in cultured mouse leukaemia cells [Nikula, Alhonen-Hongisto, Seppänen & Jänne (1984) Biochem. Biophys. Res. Commun. 120, 9-14]. We have now investigated whether carnitine also influences the development of the well-known mitochondrial damage produced by the drug in L1210 leukaemia cells. Palmitate oxidation was distinctly inhibited in tumour cells exposed to 5 microM-methylglyoxal bis(guanylhydrazone) for only 7 h. Electron-microscopic examination of the drug-exposed cells revealed that more than half of the mitochondria were severely damaged. Similar exposure of the leukaemia cells to the drug in the presence of carnitine not only abolished the inhibition of fatty acid oxidation but almost completely prevented the drug-induced mitochondrial damage. The protection provided by carnitine appeared to depend on the intracellular concentration of methylglyoxal bis(guanylhydrazone), since the mitochondria-sparing effect disappeared at higher drug concentrations.

Single-cell immunofluorescence assay for terminal transferase: human leukaemic and non-leukaemic cells.

PubMed

Okamura, S; Crane, F; Jamal, N; Messner, H A; Mak, T W

1980-02-01

The characteristics of a single-cell immunofluorescence assay for terminal deoxynucleotidyl transferase (terminal transferase, TdT) is described. The data indicate that the single-cell immunofluorescence assay is highly efficient and specific for the detection of cells containing TdT. Using this assay, we have examined 124 marrow or peripheral-blood samples from 104 patients with or without haematological malignancies. Results indicate that TdT(+) cells from 6% to 100% were found in the following patients: 34/40 samples from patients with ALL at the time of diagnosis or during relapse; 2/3 patients with acute undifferentiated leukaemia; 2/3 patients with acute myelomonocytic leukaemia; 1/24 patients with acute myeloblastic leukaemia; 1/5 patients with chronic myelocytic leukaemia (CML) in blastic crisis; and 2/2 patients with diffuse lymphoblastic lymphoma. In contrast less than 1% of TdT(+) cells were found in 20 marrow or peripheral-blood samples from ALL patients in complete remission; 8 patients with CML in chronic phase; 2 patients with myeloma; 1 sample from a patient with Hodgkin's disease, peripheral-blood samples from 7 normal donors and marrow samples from 6 patients without haematological malignancies. TdT(+) cells were also found in association with cells with lymphoblast morphology. The TdT(+) cells in marrow were shown to be directly correlated with the percentage of morphological lymphoblasts, with a Spearman rank coefficient of 0·81, significant at a 0·001 level. In 2 longitudinal studies of 2 ALL patients with TdT(+) cells at diagnosis, the percentage TdT(+) cells also changed in parallel with the proportion of lymphoblasts. However, studies of 2 other patients with morphologically diagnosed ALL with < 1% TdT(+) cells at diagnosis also showed < 1% TdT(+) cells throughout the period studied, indicating a stable phenotype of blast cells in these patients. The single-cell immunofluorescence assay for TdT, which requires < 0·1% of the cells used in

Comparative study of autophagy inhibition by 3MA and CQ on Cytarabine‑induced death of leukaemia cells.

PubMed

Palmeira dos Santos, Caroline; Pereira, Gustavo J S; Barbosa, Christiano M V; Jurkiewicz, Aron; Smaili, Soraya S; Bincoletto, Claudia

2014-06-01

As the molecular mechanisms of Cytarabine,one of the most important drugs used in the leukaemia’s treatment, are only partially understood and the role of autophagy on leukaemia development and treatment is only recently being investigated, in this study, by using Chloroquine (CQ) and 3-methyladenine (3MA) as autophagy inhibitors, we aim to evaluate the contribution of an autophagic mechanism to Cytarabine (AraC)-induced death of HL60 leukaemia cells. Trypan blue exclusion and AnnexinV/PI assays were used to evaluate HL60 cell death under AraC treatment in the presence or absence of 3MA and CQ. Western blotting and immunofluorescence experiments were performed to show the involvement of apoptosis and autophagy protein expressions. Phenotypic characterization of HL60-treated cells was performed by using immunophenotyping. Clonogenic assays were applied to analyse clonal function of HL60-treated cells. We observed that although autophagy inhibition by 3MA, but not CQ, increased the death of HL60 AraC cells after 24 h of treatment, no significant differences between AraC and AraC + 3MA-treated groups were observed by using clonogenic assay. In addition, increased number of immature (CD34(+)/CD38(−)Lin(−/low)) HL60 cells was found in AraC and AraC-3MA groups when compared with control untreated cells. Although AraC anti-leukaemia effects could be potentiated by 3MA autophagy inhibition after 24 h of exposure, leukaemia cell resistance, the main causes of treatment failure, is also promoted by autophagy initial stage impairment by 3MA, denoting the complex role of autophagy in leukaemia cells’ response to chemotherapy.

Human T cell leukaemia virus type 2 tax protein mediates CC-chemokine expression in peripheral blood mononuclear cells via the nuclear factor kappa B canonical pathway.

PubMed

Barrios, C S; Castillo, L; Zhi, H; Giam, C-Z; Beilke, M A

2014-01-01

Retroviral co-infections with human immunodeficiency virus type-1 (HIV-1) and human T cell leukaemia virus type 1 (HTLV-1) or type 2 (HTLV-2) are prevalent in many areas worldwide. It has been observed that HIV-1/HTLV-2 co-infections are associated with slower rates of CD4(+) T cell decline and delayed progression to AIDS. This immunological benefit has been linked to the ability of Tax2, the transcriptional activating protein of HTLV-2, to induce the expression of macrophage inflammatory protein (MIP)-1α/CCL3, MIP-1β/CCL4 and regulated upon activation normal T cell expressed and secreted (RANTES)/CCL5 and to down-regulate the expression of the CCR5 co-receptor in peripheral blood mononuclear cells (PBMCs). This study aimed to assess the role of Tax2-mediated activation of the nuclear factor kappa B (NF-κB) signalling pathway on the production of the anti-viral CC-chemokines MIP-1α, MIP-1β and RANTES. Recombinant Tax1 and Tax2 proteins, or proteins expressed via adenoviral vectors used to infect cells, were tested for their ability to activate the NF-κB pathway in cultured PBMCs in the presence or absence of NF-κB pathway inhibitors. Results showed a significant release of MIP-1α, MIP-1β and RANTES by PBMCs after the activation of p65/RelA and p50. The secretion of these CC-chemokines was significantly reduced (P < 0·05) by canonical NF-κB signalling inhibitors. In conclusion, Tax2 protein may promote innate anti-viral immune responses through the activation of the canonical NF-κB pathway. © 2013 British Society for Immunology.

Epstein-Barr virus and regulatory T cells in Egyptian paediatric patients with acute B lymphoblastic leukaemia.

PubMed

Ateyah, Mohamed E; Hashem, Mona E; Abdelsalam, Mohamed

2017-02-01

Acute B lymphoblastic leukaemia (B-ALL) is the most common type of childhood malignancy worldwide but little is known of its origin. Recently, many studies showed both a high incidence of Epstein-Barr virus (EBV) infection and high levels of CD4 + CD25 + Foxp3 + (Treg cells) in children with B-ALL. In our study, we investigated the possible relationship between EBV infection and the onset of B-ALL, and its relation to expression of CD4 + , CD25 high+ Foxp3+ T regulatory cells. We analysed expression and mean fluorescence intensity (MFI) of Treg cells in peripheral blood of 45 children with B-ALL and in 40 apparently healthy children as a control, using flow cytometry. Serum anti-EBV viral capsid antigen (VCA) IgG, anti-EBV nuclear antigen (EBNA) IgG (for latent infection) and anti-EBV VCA IgM (for acute infection) were investigated using ELISA. Analysis of the Treg cells population in patients and controls revealed that expression of CD4 + CD25 high+ T lymphocytes was higher in patients than in controls (mean±SD 15.7±4.1 and 10.61±2.6 in patients and controls, respectively, and MFI of Foxp3 was 30.1±7.1 and 16.7±3.7 in patients and controls, respectively (p<0.001)). There was a high incidence of latent EBV infection in patients (31%) compared with controls (10%) while the incidence of acute infection was 12% in patients and 0% in the control group. To study the role of latent EBV infection in the pathogenesis of acute B-ALL, OR was calculated (OR=4.06, coefficient index 1.2-13.6). These findings suggest a possible role for Treg cells and EBV in the pathogenesis of B-ALL. Further studies are needed on the possible mechanisms of tumour genesis related to Treg cells and EBV in children with B-ALL. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Acute B cell lymphoblastic leukaemia in a 12-week-old greyhound.

PubMed

Adams, J; Mellanby, R J; Villiers, E; Baines, S; Woodger, N

2004-11-01

A 12-week-old greyhound had a two-day history of lethargy, inappetence and shifting lameness. Clinical examination revealed pyrexia and hepatosplenomegaly. Haematological examination showed anaemia, thrombocytopenla, neutropenla and large numbers of atypical mononuclear leucocytes. A diagnosis of acute B cell lymphoblastic leukaemia was made following flow cytometric immunophenotyping of the leucocytes. The owner declined further evaluation and the dog was treated symptomatically with antibiotics. After a brief improvement, the dog's condition deteriorated and it was euthanased four days after initial presentation. The case was unusual because acute lymphoid leukaemia in the dog is most frequently reported in mature animals. This is in contrast to humans, where acute leukaemia is one of the most common childhood cancers.

Role of BAFF and APRIL in human B-cell chronic lymphocytic leukaemia

PubMed Central

Haiat, Stéphanie; Billard, Christian; Quiney, Claire; Ajchenbaum-Cymbalista, Florence; Kolb, Jean-Pierre

2006-01-01

B-cell chronic lymphocytic leukaemia (B-CLL) is the most prevalent leukaemia in Western countries and is characterized by the gradual accumulation in patients of small mature B cells. Since the vast majority of tumoral cells are quiescent, the accumulation mostly results from deficient apoptosis rather than from acute proliferation. Although the phenomenon is relevant in vivo, B-CLL cells die rapidly in vitro as a consequence of apoptosis, suggesting a lack of essential growth factors in the culture medium. Indeed, the rate of B-CLL cell death in vitro is modulated by different cytokines, some favouring the apoptotic process, others counteracting it. Two related members of the tumour necrosis factor family, BAFF (B-cell activating factor of the TNF family) and APRIL (a proliferation-inducing ligand), already known for their crucial role in normal B-cell survival, differentiation and apoptosis, were recently shown to be expressed by B-CLL cells. These molecules are able to protect the leukaemic cells against spontaneous and drug-induced apoptosis via autocrine and/or paracrine pathways. This review will focus on the role of BAFF and APRIL in the survival of tumoral cells. It will discuss the expression of these molecules by B-CLL cells, their regulation, transduction pathways and their effects on leukaemic cells. The design of reagents able to counteract the effects of these molecules seems to be a new promising therapeutic approach for B-CLL and is already currently developed in the treatment of autoimmune diseases. PMID:16827889

Chronic neutrophilic leukaemia and plasma cell-related neutrophilic leukaemoid reactions.

PubMed

Bain, Barbara J; Ahmad, Shahzaib

2015-11-01

Many cases reported as 'chronic neutrophilic leukaemia' have had an associated plasma cell neoplasm. Recent evidence suggests that the great majority of such cases represent a neutrophilic leukaemoid reaction to the underlying multiple myeloma or monoclonal gammopathy of undetermined significance. We have analysed all accessible reported cases to clarify the likely diagnosis and to ascertain whether toxic granulation, Döhle bodies and an increased neutrophil alkaline phosphatase score were useful in making a distinction between chronic neutrophilic leukaemia and a neutrophilic leukaemoid reaction. We established that all these changes occur in both conditions. Toxic granulation and Döhle bodies are more consistently present in leukaemoid reactions but also occur quite frequently in chronic neutrophilic leukaemia. The neutrophil alkaline phosphatase score is increased in both conditions and is of no value in making a distinction. © 2015 John Wiley & Sons Ltd.

Carnitine prevents the early mitochondrial damage induced by methylglyoxal bis(guanylhydrazone) in L1210 leukaemia cells.

PubMed Central

Nikula, P; Ruohola, H; Alhonen-Hongisto, L; Jänne, J

1985-01-01

We previously found that the anti-cancer drug methylglyoxal bis(guanylhydrazone) (mitoguazone) depresses carnitine-dependent oxidation of long-chain fatty acids in cultured mouse leukaemia cells [Nikula, Alhonen-Hongisto, Seppänen & Jänne (1984) Biochem. Biophys. Res. Commun. 120, 9-14]. We have now investigated whether carnitine also influences the development of the well-known mitochondrial damage produced by the drug in L1210 leukaemia cells. Palmitate oxidation was distinctly inhibited in tumour cells exposed to 5 microM-methylglyoxal bis(guanylhydrazone) for only 7 h. Electron-microscopic examination of the drug-exposed cells revealed that more than half of the mitochondria were severely damaged. Similar exposure of the leukaemia cells to the drug in the presence of carnitine not only abolished the inhibition of fatty acid oxidation but almost completely prevented the drug-induced mitochondrial damage. The protection provided by carnitine appeared to depend on the intracellular concentration of methylglyoxal bis(guanylhydrazone), since the mitochondria-sparing effect disappeared at higher drug concentrations. Images Fig. 1. PMID:3837667

Clinicopathological analysis of the age-related differences in patients with Epstein-Barr virus (EBV)-associated extranasal natural killer (NK)/T-cell lymphoma with reference to the relationship with aggressive NK cell leukaemia and chronic active EBV infection-associated lymphoproliferative disorders.

PubMed

Takahashi, Emiko; Ohshima, Koichi; Kimura, Hiroshi; Hara, Kazuo; Suzuki, Ritsuro; Kawa, Keisei; Eimoto, Tadaaki; Nakamura, Shigeo

2011-10-01

Extranodal natural killer (NK)/T-cell lymphoma (NKTL), comprising nasal NKTL and extranasal NKTL (ENKTL), is associated with Epstein-Barr virus (EBV). A bimodal age distribution was noted in NKTL patients. We examined the clinicopathological differences between two age groups of ENKTL patients (n = 23) and compared the findings with those of aggressive NK cell leukaemia (ANKL; n = 10) and monoclonal chronic active EBV infection-associated T/NK-cell lymphoproliferative disorders [chronic active EBV infection/TNK-lymphoproliferative disorders (CAEBV/TNK-LPD)] of NK-cell type (n = 45). Distinct differences existed between elderly (> 50 years; n = 13) and younger (≤ 50 years; n = 10) ENKTL patients; the latter showed a higher disease stage (P = 0.0286), worse performance status (P = 0.0244), more frequent B symptoms (P = 0.0286) and more frequent liver, spleen and bone marrow involvement (P = 0.0222, 0.0005 and 0.0259, respectively). Few clinicopathological differences existed between younger ENKTL and ANKL patients. Patients with monoclonal CAEBV/TNK-LPD of NK-cell type (n = 45) showed features similar to those in younger ENKTL/ANKL patients, except a more juvenile onset of CAEBV-related symptoms and better prognosis. However, the onset age of overt leukaemia/lymphoma in CAEBV/TNK-LPD patients and overall survival thereafter were similar to those in younger ENKTL/ANKL patients. ENKTL (≤ 50 years) is distinct from that in elderly patients and may encompass ANKL and overlap in the clinicopathological profile with NK-cell type CAEBV/TNK-LPD. 2011 Blackwell Publishing Limited.

Activity of Bruton's tyrosine-kinase inhibitor ibrutinib in patients with CD117-positive acute myeloid leukaemia: a mechanistic study using patient-derived blast cells.

PubMed

Rushworth, Stuart A; Pillinger, Genevra; Abdul-Aziz, Amina; Piddock, Rachel; Shafat, Manar S; Murray, Megan Y; Zaitseva, Lyubov; Lawes, Matthew J; MacEwan, David J; Bowles, Kristian M

2015-05-01

Roughly 80% of patients with acute myeloid leukaemia have high activity of Bruton's tyrosine-kinase (BTK) in their blast cells compared with normal haemopoietic cells, rendering the cells sensitive to the oral BTK inhibitor ibrutinib in vitro. We aimed to develop the biological understanding of the BTK pathway in acute myeloid leukaemia to identify clinically relevant diagnostic information that might define a subset of patients that should respond to ibrutinib treatment. We obtained acute myeloid leukaemia blast cells from unselected patients attending our UK hospital between Feb 19, 2010, and Jan 20, 2014. We isolated primary acute myeloid leukaemia blast cells from heparinised blood and human peripheral blood mononuclear cells to establish the activity of BTK in response to CD117 activation. Furthermore, we investigated the effects of ibrutinib on CD117-induced BTK activation, downstream signalling, adhesion to primary bone-marrow mesenchymal stromal cells, and proliferation of primary acute myeloid leukaemia blast cells. We used the Mann-Whitney U test to compare results between groups. We obtained acute myeloid leukaemia blast cells from 29 patients. Ibrutinib significantly inhibited CD117-mediated proliferation of primary acute myeloid leukaemia blast cells (p=0·028). CD117 activation increased BTK activity by inducing phosphorylated BTK in patients with CD117-positive acute myeloid leukaemia. Furthermore, ibrutinib inhibited CD117-induced activity of BTK and downstream kinases at a concentration of 100 nM or more. CD117-mediated adhesion of CD117-expressing blast cells to bone-marrow stromal cells was significantly inhibited by Ibrutinib at 500 nM (p=0·028) INTERPRETATION: As first-in-man clinical trials of ibrutinib in patients with acute myeloid leukaemia commence, the data suggest not all patients will respond. Our findings show that BTK has specific pro-tumoural biological actions downstream of surface CD117 activation, which are inhibited by ibrutinib

Ajoene, a garlic-derived natural compound, enhances chemotherapy-induced apoptosis in human myeloid leukaemia CD34-positive resistant cells.

PubMed

Ahmed, N; Laverick, L; Sammons, J; Zhang, H; Maslin, D J; Hassan, H T

2001-01-01

The reputation of garlic as an effective remedy for tumours extends back to the Egyptian Codex Ebers of 1550 BC. Several garlic compounds, including allicin and its corresponding sulfide, inhibit the proliferation of several human malignant cells. Ajoene is a garlic-derived compound produced most efficiently from pure allicin and has the advantage of a greater chemical stability than allicin. Recently, ajoene was shown to inhibit proliferation and induce apoptosis of human leukaemia CD34-negative cells including HL-60, U937, HEL and OCIM-I. More significantly, ajoene was shown to induce 30% apoptosis in myeloblasts from a chronic myeloid leukaemia patient in blastic crisis. Acute myeloid leukaemia (AML) is a heterogeneous malignant disease in which disease progression at the level of CD34-positive cells has a major impact on resistance to chemotherapy and relapse. The aim of the present study was to investigate the effect of ajoene on changes in the expression of apoptosis-related proteins: bcl-2 and caspase-3, induced by two principal drugs used in treatment of AML, cytarabine and fludarabine, in KGI human myeloid leukaemia CD34-positive-resistant cells. Both quantitative ELISA measurement of bcl-2 and colourimetric measurement of active caspase-3 were used. Quantitative ELISA measurement of bcl-2 (units per million cells) showed treatment of KG1-resistant leukaemia cells with 40 microM ajoene alone to significantly reduce the bcl-2-expression from 239.5 +/- 1.5 in control cultures to only 22.0 +/- 4.0 in ajoene-treated cultures. Fludarabine had significantly more inhibitory effect on bcl-2-expression than cytarabine in KGI-resistant myeloid leukaemia cells. Ajoene significantly enhanced the inhibitory effect of the two chemotherapeutic drugs, cytarabine and fludarabine, on bcl-2-expression in KGI cells. Bcl-2-expression could not be detected in fludarabine + ajoene-treated cultures. The Western blot of bcl-2-expression in KGI control and treated cells confirmed

Hairy Cell Leukaemia in Oman

PubMed Central

Kurukulasuriya, Arundathi; Al-Rashdi, Asia; Al-Muslahi, Muhanna

2008-01-01

Hairy cell leukaemia (HCL) is a rare, clonal, chronic lymphoproliferative disorder commonly seen in males in the middle years of life. Pancytopaenia with moderate to massive splenomegaly is the most common clinical presentation. Diagnosis is made on detecting the lymphocytes with abundant cytoplasm which spread into hair-like processes on peripheral blood and bone marrow smears, thus giving the name, “hairy cell leukaemia”. The bone marrow aspirate is frequently a dry tap. The trephine biopsy has the characteristic features of a honey comb appearance and flow cytometry is typically CD103, CD25, FMC7, CD11c, gamma or kappa light chain positive with the classic B lymphocyte markers CD19, CD20, CD79a. Purine analogues followed by granulocyte-colony stimulating factor (G-CSF) to manage the febrile neutropenia is currently the treatment of choice. A 10 year disease free survival is recorded with these management strategies. Experimental use of anti CD20 and CD22 has also shown promising results in the treatment of this disease. We report four cases of HCL diagnosed in a span of two years at the Royal Hospital, Muscat, Oman. PMID:21748080

[Immunophenotype of lymphoblastic leukaemia in children in relation to clinical symptoms and laboratory tests, preceding its diagnosis].

PubMed

Zapolska, Beata; Krawczuk-Rybak, Maryna; Łuczyński, Włodzimierz; Zak, Janusz; Leszczyńska, Elzbieta

2004-01-01

The aim of study was to compare the clinical picture and results of laboratory tests according to the acute lymphoblastic leukaemia (ALL) immunophenotype. The observation was carried out on a group of 67 patients treated in the IIIrd Department of Paediatrics and Department of Children Oncology in the Medical Academy of Białystok from January 1994 to April 2001. This group consists of 4 children with pro-B acute lymphoblastic leukaemia, 52 children with pre-B cell ALL, 1 child with B-cell acute lymphoblastic leukaemia and 9 children with T-cell acute lymphoblastic leukaemia. Haemorrhagic diathesis. splenomegaly, enlargement of peripheral lymph nodes as well as higher values of white blood cells count, blasts count, haemoglobin concentration, haematocrit and LDH activity were observed more frequently in patients with T-cell leukaemia than in others.

Genomic characterization of Imatinib resistance in CD34+ cell populations from chronic myeloid leukaemia patients.

PubMed

Joha, Sami; Dauphin, Véronique; Leprêtre, Frédéric; Corm, Sélim; Nicolini, Franck E; Roumier, Christophe; Nibourel, Olivier; Grardel, Nathalie; Maguer-Satta, Véronique; Idziorek, Thierry; Figeac, Martin; Laï, Jean-Luc; Quesnel, Bruno; Etienne, Gabriel; Guilhot, François; Lippert, Eric; Preudhomme, Claude; Roche-Lestienne, Catherine

2011-04-01

To ascertain genomic alterations associated with Imatinib resistance in chronic myeloid leukaemia, we performed high resolution genomic analysis of CD34(+) cells from 25 Imatinib (IM) resistant and 11 responders CML patients. Using patients' T-cells as reference, we found significant association between number of acquired cryptic copy number alterations (CNA) and disease phase (p=0.036) or loss of IM response for patients diagnosed in chronic phase (CP) (p=0.04). Recurrent cryptic losses were identified on chromosomes 7, 12 and 13. On chromosome 7, recurrent deletions of the IKZF1 locus were detected, for the first time, in 4 patients in CP. Copyright © 2010 Elsevier Ltd. All rights reserved.

Two rare diagnoses during chronic lymphocytic leukaemia follow-up: Kaposi's sarcoma and Merkel cell carcinoma.

PubMed

Dogu, Mehmet H; Sari, Ismail; Hacioglu, Sibel; Degirmencioglu, Serkan; Şen, Nilay; Keskin, Ali

2016-02-01

Chronic lymphocytic leukaemia often has a clinical presentation characterised by increased neoplastic lymphocytes which are mostly mature looking due to B lymphocytes. Increased secondary cancer prevalence has been detected among patients with chronic lymphocytic leukaemia diagnosis. In this report, we present three chronic lymphocytic leukaemia patients who developed secondary rare cancers during their follow-up at our clinic. Case 1: A 54-year-old female patient was diagnosed with stage I chronic lymphocytic leukaemia in 2003 and was diagnosed with Merkel cell carcinoma in February 2013. Case 2: A 66-year-old male patient was diagnosed with stage II chronic lymphocytic leukaemia in 2009 and was diagnosed with Kaposi's sarcoma in March 2013. Case 3: A 77-year-old male patient was diagnosed with stage I chronic lymphocytic leukaemia in 2006 and was diagnosed with Kaposi's sarcoma in 2011. In conclusion, secondary cancers are observed in patients diagnosed with chronic lymphocytic leukaemia. Therefore, follow-up of chronic lymphocytic leukaemia requires additional attention in this context. © The Author(s) 2016.

Long-term follow-up of patients receiving allogeneic stem cell transplant for chronic lymphocytic leukaemia: mixed T-cell chimerism is associated with high relapse risk and inferior survival.

PubMed

Thompson, Philip A; Stingo, Francesco; Keating, Michael J; Wierda, William G; O'Brien, Susan M; Estrov, Zeev; Ledesma, Celina; Rezvani, Katayoun; Qazilbash, Muzaffar; Shah, Nina; Parmar, Simrit; Popat, Uday; Anderlini, Paolo; Yago, Nieto; Ciurea, Stefan O; Kebriaei, Partow; Champlin, Richard; Shpall, Elizabeth J; Hosing, Chitra M

2017-05-01

There is limited information regarding the immunological predictors of post-allogeneic stem cell transplant (alloSCT) outcome in chronic lymphocytic leukaemia (CLL), such as mixed T-cell chimerism. We analysed 143 consecutive patients with relapsed/refractory CLL, transplanted between 2000 and 2012, to determine the prognostic relevance of mixed chimerism post-alloSCT and the ability of post-transplant immunomodulation to treat relapse. Mixed T-cell chimerism occurred in 50% of patients at 3 months and 43% at 6 months post-alloSCT; upon 3- and 6-month landmark analysis, this was associated with inferior progression-free survival (PFS) [Hazard ratio (HR) 1·93, P = 0·003 and HR 2·58, P < 0·001] and survival (HR 1·66, P = 0·05 and HR 2·17, P < 0·001), independent of baseline patient characteristics, and a lower rate of grade II-IV acute graft-versus-host disease (GHVD) (16% vs. 52%, P < 0·001). Thirty-three patients were treated with immunomodulation for relapse post-alloSCT (immunosuppression withdrawal, n = 6, donor lymphocyte infusion, n = 27); 17 achieved complete response (CR), which predicted superior PFS (53 months vs. 10 months, P < 0·001) and survival (117 months vs. 30 months, P = 0·006). Relapsed patients with mixed chimerism had inferior response to immunomodulation; conversion to full donor chimerism was highly correlated both with CR and with the development of severe acute GVHD, which was fatal in 3/8 patients. Novel therapeutic strategies are required for patients with mixed T-cell chimerism post-alloSCT for CLL. © 2017 John Wiley & Sons Ltd.

Fv1-like restriction of N-tropic replication-competent murine leukaemia viruses in mCAT-1-expressing human cells.

PubMed

Aagaard, Lars; Mikkelsen, Jacob Giehm; Warming, Søren; Duch, Mogens; Pedersen, Finn Skou

2002-02-01

To study the replication of murine leukaemia viruses in human cells we have used full-length as well as EGFP-tagged ecotropic viruses in combination with mCAT-1-expressing human cells. We present results showing that N-tropic murine leukaemia viruses are restricted in both infection and replication in such cells while B-tropic viruses, modified at capsid position 110, escape restriction. These results support a recently reported Fv1-like restriction in mammalian cells. We extend the analysis of Fv1-like restriction by demonstrating that NB-tropic viruses also escape restriction and human mCAT-1-expressing cells are thus similar to murine Fv1(b) cells with respect to infection though the ecotropic receptor pathway.

Application of a haematopoetic progenitor cell-targeted adeno-associated viral (AAV) vector established by selection of an AAV random peptide library on a leukaemia cell line

PubMed Central

Stiefelhagen, Marius; Sellner, Leopold; Kleinschmidt, Jürgen A; Jauch, Anna; Laufs, Stephanie; Wenz, Frederik; Zeller, W Jens; Fruehauf, Stefan; Veldwijk, Marlon R

2008-01-01

Background For many promising target cells (e.g.: haematopoeitic progenitors), the susceptibility to standard adeno-associated viral (AAV) vectors is low. Advancements in vector development now allows the generation of target cell-selected AAV capsid mutants. Methods To determine its suitability, the method was applied on a chronic myelogenous leukaemia (CML) cell line (K562) to obtain a CML-targeted vector and the resulting vectors tested on leukaemia, non-leukaemia, primary human CML and CD34+ peripheral blood progenitor cells (PBPC); standard AAV2 and a random capsid mutant vector served as controls. Results Transduction of CML (BV173, EM3, K562 and Lama84) and AML (HL60 and KG1a) cell lines with the capsid mutants resulted in an up to 36-fold increase in CML transduction efficiency (K562: 2-fold, 60% ± 2% green fluorescent protein (GFP)+ cells; BV173: 9-fold, 37% ± 2% GFP+ cells; Lama84: 36-fold, 29% ± 2% GFP+ cells) compared to controls. For AML (KG1a, HL60) and one CML cell line (EM3), no significant transduction (<1% GFP+ cells) was observed for any vector. Although the capsid mutant clone was established on a cell line, proof-of-principle experiments using primary human cells were performed. For CML (3.2-fold, mutant: 1.75% ± 0.45% GFP+ cells, p = 0.03) and PBPC (3.5-fold, mutant: 4.21% ± 3.40% GFP+ cells) a moderate increase in gene transfer of the capsid mutant compared to control vectors was observed. Conclusion Using an AAV random peptide library on a CML cell line, we were able to generate a capsid mutant, which transduced CML cell lines and primary human haematopoietic progenitor cells with higher efficiency than standard recombinant AAV vectors. PMID:18789140

Durable graft-versus-leukaemia effects without donor lymphocyte infusions - results of a phase II study of sequential T-replete allogeneic transplantation for high-risk acute myeloid leukaemia and myelodysplasia.

PubMed

Davies, Jeff K; Hassan, Sandra; Sarker, Shah-Jalal; Besley, Caroline; Oakervee, Heather; Smith, Matthew; Taussig, David; Gribben, John G; Cavenagh, Jamie D

2018-02-01

Allogeneic haematopoietic stem-cell transplantation remains the only curative treatment for relapsed/refractory acute myeloid leukaemia (AML) and high-risk myelodysplasia but has previously been limited to patients who achieve remission before transplant. New sequential approaches employing T-cell depleted transplantation directly after chemotherapy show promise but are burdened by viral infection and require donor lymphocyte infusions (DLI) to augment donor chimerism and graft-versus-leukaemia effects. T-replete transplantation in sequential approaches could reduce both viral infection and DLI usage. We therefore performed a single-arm prospective Phase II clinical trial of sequential chemotherapy and T-replete transplantation using reduced-intensity conditioning without planned DLI. The primary endpoint was overall survival. Forty-seven patients with relapsed/refractory AML or high-risk myelodysplasia were enrolled; 43 proceeded to transplantation. High levels of donor chimerism were achieved spontaneously with no DLI. Overall survival of transplanted patients was 45% and 33% at 1 and 3 years. Only one patient developed cytomegalovirus disease. Cumulative incidences of treatment-related mortality and relapse were 35% and 20% at 1 year. Patients with relapsed AML and myelodysplasia had the most favourable outcomes. Late-onset graft-versus-host disease protected against relapse. In conclusion, a T-replete sequential transplantation using reduced-intensity conditioning is feasible for relapsed/refractory AML and myelodysplasia and can deliver graft-versus-leukaemia effects without DLI. © 2017 John Wiley & Sons Ltd.

Lysosomal isoenzyme profiles used to classify a case of acute undifferentiated leukaemia.

PubMed

Eden, O B; Darbyshire, P; Simpson, R M; Besley, G T; Moss, S; Gentle, T

1985-01-01

Lysosomal enzyme activities and isoenzyme profiles were measured in lymphoid and non-lymphoid leukaemic cells from childhood patients. High activities, especially of beta-hexosaminidase and alpha-mannosidase, were associated with leukaemic cells of myeloid or monocytic origin. Leukaemic cells from two children with acute myeloid leukaemia had a relative reduction in the B isoenzyme of beta-hexosaminidase activity, whereas in patients with non T, non B cell acute lymphoblastic leukaemia, intermediate beta-hexosaminidase isoenzymes were expressed. A patient is described on whom conventional marker studies were either negative or equivocal, but lysosomal enzyme markers were consistent with a myeloid leukaemia. This observation was supported by the clinical course of this patient.

Effect of Anacardium occidentale leaf extract on human acute lymphoblastic leukaemia cell lines.

PubMed

Santos, Janaína M; Cury, Nathalia M; Yunes, José A; López, Jorge A; Hernández-Macedo, Maria L

2018-01-16

Anacardium occidentale leaves are used in folk medicine due its therapeutic properties attributed to phenolic compounds. Therefore, this study was undertaken on its hydroethanolic leaf extract (AoHE) to evaluate cytotoxicity and apoptosis induction on acute lymphoblastic leukaemia cells. Results indicated that AoHE interfered in the cell cycle progression, inducing apoptosis by activation of casp3 at lower concentrations, thence, a promising candidate for the development of new cancer drugs.

Glycometabolic adaptation mediates the insensitivity of drug-resistant K562/ADM leukaemia cells to adriamycin via the AKT-mTOR/c-Myc signalling pathway.

PubMed

Zhang, Xueyan; Ai, Ziying; Chen, Jing; Yi, Juan; Liu, Zhuan; Zhao, Huaishun; Wei, Hulai

2017-04-01

In human leukaemia, resistance to chemotherapy leads to treatment ineffectiveness or failure. Previous studies have indicated that cancers with increased levels of aerobic glycolysis are insensitive to numerous forms of chemotherapy and respond poorly to radiotherapy. Whether glycolysis serves a key role in drug resistance of leukaemia cells remains unclear. The present study systematically investigated aerobic glycolytic alterations and regulation in K562/adriamycin (ADM) multidrug‑resistant (MDR) and ADM‑sensitive K562 leukaemia cells in normoxia, and the association between drug resistance and improper glycometabolism. The cell proliferating activity was assessed with an MTT colorimetric assay, glycolysis, including glucose consumption, lactate export and key‑enzyme activity was determined by corresponding commercial testing kits. The expression levels of hexokinase‑II (HK‑II), lactate dehydrogenase A (LDHA), glucose transporter‑4 (GLUT‑4), AKT, p‑AKT473/308, mammalian target of rapamycin (mTOR), p‑mTOR, c‑Myc and hypoxia‑inducible factor‑1α (HIF‑1α) were analyzed by western blot or reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). K562/ADM cells exhibited increased glucose consumption and lactate accumulation, increased lactate dehydrogenase, hexokinase and pyruvate kinase activities, and reduced phosphofructokinase activity. In addition, K562/ADM cells expressed significantly more HK‑II and GLUT‑4. Notably, inhibition of glycolysis effectively killed sensitive and resistant leukaemia cells and potently restored the sensitivity of MDR cells to the anticancer agent ADM. The AKT serine/threonine kinase (AKT)/mechanistic target of rapamycin (mTOR) signalling pathway, a crucial regulator of glycometabolic homeostasis, mediated over‑activation and upregulation of c‑Myc expression levels in K562/ADM cells, which directly stimulated glucose consumption and enhanced glycolysis. In conclusion, the present

Lethal Giant Larvae 1 Tumour Suppressor Activity Is Not Conserved in Models of Mammalian T and B Cell Leukaemia

PubMed Central

Hawkins, Edwin D.; Oliaro, Jane; Ramsbottom, Kelly M.; Ting, Stephen B.; Sacirbegovic, Faruk; Harvey, Michael; Kinwell, Tanja; Ghysdael, Jacques; Johnstone, Ricky W.; Humbert, Patrick O.; Russell, Sarah M.

2014-01-01

In epithelial and stem cells, lethal giant larvae (Lgl) is a potent tumour suppressor, a regulator of Notch signalling, and a mediator of cell fate via asymmetric cell division. Recent evidence suggests that the function of Lgl is conserved in mammalian haematopoietic stem cells and implies a contribution to haematological malignancies. To date, direct measurement of the effect of Lgl expression on malignancies of the haematopoietic lineage has not been tested. In Lgl1−/− mice, we analysed the development of haematopoietic malignancies either alone, or in the presence of common oncogenic lesions. We show that in the absence of Lgl1, production of mature white blood cell lineages and long-term survival of mice are not affected. Additionally, loss of Lgl1 does not alter leukaemia driven by constitutive Notch, c-Myc or Jak2 signalling. These results suggest that the role of Lgl1 in the haematopoietic lineage might be restricted to specific co-operating mutations and a limited number of cellular contexts. PMID:24475281

Enzyme and membrane markers in leukaemia: recent developments.

PubMed Central

Hoffbrand, A V; Janossy, G

1981-01-01

Terminal deoxynucleotidyl transferase (TdT) assay has proved a valuable test for distinguishing lymphoblastic from myeloblastic leukaemias, particularly in adults whose blast cells are often negative for the c-ALL antigen. The immunofluorescence assay, particularly when used in combination with antisera to surface membrane antigens, has proved a sensitive technique for detecting small numbers of lymphoblasts in extramedullary sites, for example, testis or cerebrospinal fluid, or of residual Thy-ALL blasts in the marrow, which might otherwise be difficult to recognise. Differences in concentration of several enzymes concerned in purine metabolism have been detected between the blast cells in the various acute leukaemias. Adenosine deaminase (ADA) concentrations tend to be higher in Thy-ALL than in other forms of leukaemia, but the wide overlap reduces the diagnostic value of this assay. Thy-ALL blasts, however, appear to be selectively and exquisitely susceptible to inhibition of ADA by the drug deoxycoformycin, which has now been used sucessfully in a number of other wise resistant patients with Thy-ALL to obtain a complete remission. The recently introduced technique for the production of monoclonal antibodies has substantially widened the reagents available for analysing the membrane characteristics of bone marrow stem cells and of cell lineages derived from them. These have revealed previously unsuspected heterogeneity among different cases of acute lymphoblastic leukaemia, for example, among Thy-ALL blasts from different patients, and they have also delineated minor populations of immature thymocytes from which these leukaemic cells are derived. The potential use of these antibodies to prevent graft-versus-host disease by selective removal of T-lymphocytes from donor bone marrow before allogeneic bone marrow transplantation, or to prevent recurrence of Thy-ALL and other lymphoblastic leukaemias or lymphomas by selective removal of leukaemic or lymphoma

Loss of Oncogenic Notch1 with Resistance to a PI3K Inhibitor in T Cell Leukaemia

PubMed Central

Dail, Monique; Wong, Jason; Lawrence, Jessica; O’Connor, Daniel; Nakitandwe, Joy; Chen, Shann-Ching; Xu, Jin; Lee, Leslie B; Akagi, Keiko; Li, Qing; Aster, Jon C.; Pear, Warren S.; Downing, James R; Sampath, Deepak; Shannon, Kevin

2014-01-01

Mutations that deregulate Notch1 and Ras/PI3 kinase/Akt signalling are prevalent in T lineage acute lymphoblastic leukaemia (T-ALL), and often coexist. The PI3 kinase inhibitor GDC-0941 was active against primary T-ALLs from wild-type and KrasG12D mice and addition of the MEK inhibitor PD0325901 increased efficacy. Mice invariably relapsed after treatment with drug resistant clones, most of which unexpectedly had reduced levels of activated Notch1 protein, down-regulated many Notch1 target genes, and exhibited cross-resistance to γ secretase inhibitors. Multiple resistant primary T-ALLs that emerged in vivo did not contain somatic Notch1 mutations present in the parental leukaemia. Importantly, resistant clones up-regulated PI3K signalling. Consistent with these data, inhibiting Notch1 activated the PI3K pathway, providing a likely mechanism for selection against oncogenic Notch1 signalling. These studies validate PI3K as a therapeutic target in T-ALL and raise the unexpected possibility that dual inhibition of PI3K and Notch1 signalling could facilitate drug resistance in T-ALL. PMID:25043004

The versatile landscape of haematopoiesis: are leukaemia stem cells as versatile?

PubMed

Brown, Geoffrey; Hughes, Philip J; Ceredig, Rhodri

2012-01-01

Since the early 1980s, developing haematopoietic cells have been categorised into three well-defined compartments: multi-potent haematopoietic stem cells (HSC), which are able to self-renew, followed by haematopoietic progenitor cells (HPC), which undergo decision-making and age as they divide rather than self-renew, and the final compartment of functional blood and immune cells. The classic model of haematopoiesis divides cells into two families, myeloid and lymphoid, and dictates a route to a particular cell fate. New discoveries question these long-held principles, including: (i) the identification of lineage-biased cells that self-renew; (ii) a strict myeloid/lymphoid dichotomy is refuted by the existence of progenitors with lymphoid potential and an incomplete set of myeloid potentials; (iii) there are multiple routes to some end cell types; and (iv) thymocyte progenitor cells that have progressed some way along this pathway retain clandestine myeloid options. In essence, the progeny of HSC are more versatile and the process of haematopoiesis is more flexible than previously thought. Here we examine this new way of viewing haematopoiesis and the impact of rewriting an account of haematopoiesis on our understanding of what goes awry in leukaemia.

Increased post-induction intensification improves outcome in children and adolescents with a markedly elevated white blood cell count (≥200 × 10(9) /l) with T cell acute lymphoblastic leukaemia but not B cell disease: a report from the Children's Oncology Group.

PubMed

Hastings, Caroline; Gaynon, Paul S; Nachman, James B; Sather, Harland N; Lu, Xiaomin; Devidas, Meenakshi; Seibel, Nita L

2015-02-01

Children and adolescents presenting with a markedly elevated white blood cell (ME WBC) count (WBC ≥200 × 10(9) /l) comprise a unique subset of high-risk patients with acute lymphoblastic leukaemia (ALL). We evaluated the outcomes of the 251 patients (12% of the study population) with ME WBC treated on the Children's Cancer Group-1961 protocol. Patients were evaluated for early response to treatment by bone marrow morphology; those with a rapid early response were randomized to treatment regimens testing longer and stronger post-induction therapy. We found that ME WBC patients have a poorer outcome compared to those patients presenting with a WBC <200 × 10(9) /l (5-year event-free survival 62% vs. 73%, P = 0·0005). Longer duration of therapy worsened outcome for T cell ME WBC with a trend to poorer outcome in B-ALL ME WBC patients. Augmented therapy benefits T cell ME WBC patients, similar to the entire study cohort, however, there appeared to be no impact on survival for B-ALL ME WBC patients. ME WBC was not a prognostic factor for T cell patients. In patients with high risk features, B lineage disease in association with ME WBC has a negative impact on survival. © 2014 John Wiley & Sons Ltd.

Holoprosencephaly and Pure Red Cell Aplasia in a Feline Leukaemia Virus-Positive Kitten.

PubMed

Southard, T L; Rodriguez-Ramos Fernandez, J; Priest, H; Stokol, T

2016-01-01

A 9-month-old, female, domestic longhair cat with severe anaemia tested positive for feline leukaemia virus (FeLV) and was humanely destroyed and submitted for necropsy examination. Gross findings included a non-divided rostral telencephalon, consistent with semilobar holoprosencephaly. Histological examination of the bone marrow revealed an almost complete absence of erythroid precursor cells, consistent with pure red cell aplasia, and mild to moderate myelofibrosis. This case demonstrates a very unusual central nervous system defect, as well as an atypical presentation of pure red cell aplasia, in a FeLV-positive kitten. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Culture-Repopulating Ability Assays and Incubation in Low Oxygen: A Simple Way to Test Drugs on Leukaemia Stem or Progenitor Cells

PubMed Central

Cipolleschi, Maria Grazia; Rovida, Elisabetta; Sbarba, Persio Dello

2013-01-01

The Culture-Repopulating Ability (CRA) assays is a method to measure in vitro the bone marrow-repopulating potential of haematopoietic cells. The method was developed in our laboratory in the course of studies based on the use of growth factor-supplemented liquid cultures to study haematopoietic stem/progenitor cell resistance to, and selection at, low oxygen tensions in the incubation atmosphere. These studies led us to put forward the first hypothesis of the existence in vivo of haematopoietic stem cell niches where oxygen tension is physiologically lower than in other bone marrow areas. The CRA assays and incubation in low oxygen were later adapted to the study of leukaemias. Stabilized leukaemia cell lines, ensuring genetically homogeneous cells and enhancing repeatability of results, were found nevertheless phenotypically heterogeneous, comprising cell subsets exhibiting functional phenotypes of stem or progenitor cells. These subsets can be assayed separately, provided an experimental system capable to select one from another (such as different criteria for incubation in low oxygen) is established. On this basis, a two-step procedure was designed, including a primary culture of leukaemia cells in low oxygen for different times, where drug treatment is applied, followed by the transfer of residual cell population (CRA assay) to a drug-free secondary culture incubated at standard oxygen tension, where the expansion of population is allowed. The CRA assays, applied to cell lines first and then to primary cells, represent a simple and relatively rapid, yet accurate and reliable, method for the pre-screening of drugs potentially active on leukaemias which in our opinion could be adopted systematically before they are tested in vivo. PMID:23394087

TESTIN Induces Rapid Death and Suppresses Proliferation in Childhood B Acute Lymphoblastic Leukaemia Cells

PubMed Central

Weeks, Robert J.; Ludgate, Jackie L.; LeMée, Gwenn; Morison, Ian M.

2016-01-01

Background Childhood acute lymphoblastic leukaemia (ALL) is the most common malignancy in children. Despite high cure rates, side effects and late consequences of the intensive treatments are common. Unquestionably, the identification of new therapeutic targets will lead to safer, more effective treatments. We identified TES promoter methylation and transcriptional silencing as a very common molecular abnormality in childhood ALL, irrespective of molecular subtype. The aims of the present study were to demonstrate that TES promoter methylation is aberrant, to determine the effects of TES re-expression in ALL, and to determine if those effects are mediated via TP53 activity. Methods Normal fetal and adult tissue DNA was isolated and TES promoter methylation determined by Sequenom MassARRAY. Quantitative RT-PCR and immunoblot were used to confirm re-expression of TES in ALL cell lines after 5’-aza-2’-deoxycytidine (decitabine) exposure or transfection with TES expression plasmids. The effects of TES re-expression on ALL cells were investigated using standard cell proliferation, cell death and cell cycle assays. Results In this study, we confirm that the TES promoter is unmethylated in normal adult and fetal tissues. We report that decitabine treatment of ALL cell lines results in demethylation of the TES promoter and attendant expression of TES mRNA. Re-expression of TESTIN protein in ALL cells using expression plasmid transfection results in rapid cell death or cell cycle arrest independent of TP53 activity. Conclusions These results suggest that TES is aberrantly methylated in ALL and that re-expression of TESTIN has anti-leukaemia effects which point to novel therapeutic opportunities for childhood ALL. PMID:26985820

The downregulation of miR-3173 in B-cell acute lymphoblastic leukaemia promotes cell invasion via PTK2.

PubMed

Tian, Lijun; Cao, Junhua; Ji, Qiang; Zhang, Chuanling; Qian, Tong; Song, Xianchuan; Huang, Baoshan; Tian, Xinyi

2017-12-16

MicroRNAs are important regulators of the pathogenesis of B-cell acute lymphoblastic leukaemia (B-ALL). In this study, we identified miR-3173 and its predicted target gene PTK2 were correspondingly differentially expressed in B-ALL patients. In B-ALL cell lines, CCK-8 proliferation assay revealed that miR-3173 could inhibit the cell proliferation. Moreover, transwell assay revealed that miR-3173 could also inhibit cell migration and invasion in B-ALL cell lines. Luciferase assays revealed that miR-3173 directly bound to the 3'untranslated region of PTK2, and western blotting showed that miR-3173 suppressed the expression of PTK2 at the protein level. Generally, this study indicates that miR-3173 negatively regulates PTK2 and inhibits proliferation and invasion of B-ALL cell lines. Thus, miR-3173 may represent a potential therapeutic molecule for B-ALL intervention. Copyright © 2017 Elsevier Inc. All rights reserved.

Silver nanoparticles exhibit size-dependent differential toxicity and induce expression of syncytin-1 in FA-AML1 and MOLT-4 leukaemia cell lines.

PubMed

Alqahtani, Sultan; Promtong, Pawika; Oliver, Anthony W; He, Xiaotong T; Walker, Thomas D; Povey, Andrew; Hampson, Lynne; Hampson, Ian N

2016-11-01

Human endogenous retrovirus (HERV) sequences make up ~8% of the human genome and increased expression of some HERV proteins has been observed in various pathologies including leukaemia and multiple sclerosis. However, little is known about the function of these HERV proteins or environmental factors which regulate their expression. Silver nanoparticles (AgNPs) are used very extensively as antimicrobials and antivirals in numerous consumer products although their effect on the expression of HERV gene products is unknown. Cell proliferation and cell toxicity assays were carried out on human acute T lymphoblastic leukaemia (MOLT-4) and Fanconi anaemia associated acute myeloid leukaemia (FA-AML1) cells treated with two different sizes of AgNPs (7nm and 50nm diameter). Reverse-transcriptase polymerase chain reaction and western blotting were then used to the assess expression of HERV-W syncytin-1 mRNA and protein in these cells. FA-AML1 cells were more sensitive overall than MOLT-4 to treatment with the smaller 7nm sized AgNp's being the most toxic in these cells. MOLT-4 cell were more resistant and showed no evidence of differential toxicity to the different sized particles. Syncytin-1 mRNA and protein were induced by both 7 and 50nm AgNPs in both cell types yet with different kinetics. In summary, the observation that AgNPs induce expression of syncytin-1 in FA-AML1 and MOLT-4 cells at doses as little as 5 µg/ml is grounds for concern since this protein is up-regulated in both malignant and neurodegenerative diseases. Considering the widespread use of AgNPs in the environment it is clear that their ability to induce syncytin-1 should be investigated further in other cell types. © The Author 2016. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Sequential chemotherapy followed by reduced-intensity conditioning and allogeneic haematopoietic stem cell transplantation in adult patients with relapse or refractory acute myeloid leukaemia: a survey from the Acute Leukaemia Working Party of EBMT.

PubMed

Ringdén, Olle; Labopin, Myriam; Schmid, Christoph; Sadeghi, Behnam; Polge, Emmanuelle; Tischer, Johanna; Ganser, Arnold; Michallet, Mauricette; Kanz, Lothar; Schwerdtfeger, Rainer; Nagler, Arnon; Mohty, Mohamad

2017-02-01

This study analysed the outcome of 267 patients with relapse/refractory acute myeloid leukaemia (AML) who received sequential chemotherapy including fludarabine, cytarabine and amsacrine followed by reduced-intensity conditioning (RIC) and allogeneic haematopoietic stem cell transplantation (HSCT). The transplants in 77 patients were from matched sibling donors (MSDs) and those in 190 patients were from matched unrelated donors. Most patients (94·3%) were given anti-T-cell antibodies. The incidence of acute graft-versus-host disease (GVHD) of grades II-IV was 32·1% and that of chronic GVHD was 30·2%. The 3-year probability of non-relapse mortality (NRM) was 25·9%, that of relapse was 48·5%, that of GVHD-free and relapse-free survival (GRFS) was 17·8% and that of leukaemia-free survival (LFS) was 25·6%. In multivariate analysis, unrelated donor recipients more frequently had acute GVHD of grades II-IV [hazard ratio (HR) = 1·98, P = 0·017] and suffered less relapses (HR = 0·62, P = 0·01) than MSD recipients. Treatment with anti-T-cell antibodies reduced NRM (HR = 0·35, P = 0·01) and improved survival (HR = 0·49, P = 0·01), GRFS (HR = 0·37, P = 0·0004) and LFS (HR = 0·46, P = 0·005). Thus, sequential chemotherapy followed by RIC HSCT and use of anti-T-cell antibodies seems promising in patients with refractory AML. © 2016 John Wiley & Sons Ltd.

Positive regulation of deoxycytidine kinase activity by phosphorylation of Ser-74 in B-cell chronic lymphocytic leukaemia lymphocytes.

PubMed

Smal, Caroline; Van Den Neste, Eric; Maerevoet, Marie; Poiré, Xavier; Théate, Ivan; Bontemps, Françoise

2007-08-08

Deoxycytidine kinase (dCK) activates several antileukaemic nucleoside analogues. We have recently reported that the activity of dCK, overexpressed in HEK 293T cells, correlates with its phosphorylation level on Ser-74. Here, we show that dCK from B-cell chronic lymphocytic leukaemia (B-CLL) lymphocytes can be detected by an anti-phospho-Ser-74 antibody and that interindividual variability in dCK activity is related to its phosphorylation level on Ser-74. Moreover, pharmacological intervention modified Ser-74 phosphorylation, in close parallel with changes in dCK activity. These results suggest that activation of dCK via phosphorylation of Ser-74 might constitute a new therapeutic strategy to enhance activation and efficacy of nucleoside analogues.

Potential use of CD40 ligand for immunotherapy of childhood B-cell precursor acute lymphoblastic leukaemia.

PubMed

D'Amico, Giovanna; Marin, Virna; Biondi, Andrea; Bonamino, Martin Hernán

2004-09-01

Around 20% of children affected by B-cell precursor acute lymphoblastic leukaemia (BCP-ALL) still experience a recurrence of the disease after diagnosis, despite a significant improvement in the cure rate (80%). Moreover, standard therapies have high and often unacceptable acute and chronic organ toxicity, with an increased risk for secondary malignancies. Therefore, new strategies are needed to improve overall survival and decrease treatment-associated morbidity. Recent in-vitro and in-vivo studies have demonstrated that CD40 engagement improves tumour immunogenicity and, consequently, generates a strong antitumour immune response. The CD40-CD40 ligand (CD40L) system is of pivotal importance in the immune response via interactions between T cells and antigen-presenting cells. The general aim of this chapter is to review the feasibility of developing cellular strategies to increase childhood BCP-ALL immunogenicity, and the potential use of CD40L as a new strategy to induce an antileukaemia immune response in BCP-ALL.

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.

Meningeal mast cell-T cell crosstalk regulates T cell encephalitogenicity.

PubMed

Russi, Abigail E; Walker-Caulfield, Margaret E; Guo, Yong; Lucchinetti, Claudia F; Brown, Melissa A

2016-09-01

GM-CSF is a cytokine produced by T helper (Th) cells that plays an essential role in orchestrating neuroinflammation in experimental autoimmune encephalomyelitis, a rodent model of multiple sclerosis. Yet where and how Th cells acquire GM-CSF expression is unknown. In this study we identify mast cells in the meninges, tripartite tissues surrounding the brain and spinal cord, as important contributors to antigen-specific Th cell accumulation and GM-CSF expression. In the absence of mast cells, Th cells do not accumulate in the meninges nor produce GM-CSF. Mast cell-T cell co-culture experiments and selective mast cell reconstitution of the meninges of mast cell-deficient mice reveal that resident meningeal mast cells are an early source of caspase-1-dependent IL-1β that licenses Th cells to produce GM-CSF and become encephalitogenic. We also provide evidence of mast cell-T cell co-localization in the meninges and CNS of recently diagnosed acute MS patients indicating similar interactions may occur in human demyelinating disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

Carfilzomib induces leukaemia cell apoptosis via inhibiting ELK1/KIAA1524 (Elk-1/CIP2A) and activating PP2A not related to proteasome inhibition.

PubMed

Liu, Chun-Yu; Hsieh, Feng-Shu; Chu, Pei-Yi; Tsai, Wen-Chun; Huang, Chun-Teng; Yu, Yuan-Bin; Huang, Tzu-Ting; Ko, Po-Shen; Hung, Man-Hsin; Wang, Wan-Lun; Shiau, Chung-Wai; Chen, Kuen-Feng

2017-06-01

Enhancing the tumour suppressive activity of protein phosphatase 2A (PP2A) has been suggested to be an anti-leukaemic strategy. KIAA1524 (also termed CIP2A), an oncoprotein inhibiting PP2A, is associated with disease progression in chronic myeloid leukaemia and may be prognostic in cytogenetically normal acute myeloid leukaemia. Here we demonstrated that the selective proteasome inhibitor, carfilzomib, induced apoptosis in sensitive primary leukaemia cells and in sensitive leukaemia cell lines, associated with KIAA1524 protein downregulation, increased PP2A activity and decreased p-Akt, but not with the proteasome inhibition effect of carfilzomib. Ectopic expression of KIAA1524, or pretreatment with the PP2A inhibitor, okadaic acid, suppressed carfilzomib-induced apoptosis and KIAA1524 downregulation in sensitive cells, whereas co-treatment with the PP2A agonist, forskolin, enhanced carfilzomib-induced apoptosis in resistant cells. Mechanistically, carfilzomib affected KIAA1524 transcription through disturbing ELK1 (Elk-1) binding to the KIAA1524 promoter. Moreover, the drug sensitivity and mechanism of carfilzomib in xenograft mouse models correlated well with the effects of carfilzomib on KIAA1524 and p-Akt expression, as well as PP2A activity. Our data disclosed a novel drug mechanism of carfilzomib in leukaemia cells and suggests the potential therapeutic implication of KIAA1524 in leukaemia treatment. © 2017 John Wiley & Sons Ltd.

Influence of zinc deficiency on cell-membrane fluidity in Jurkat, 3T3 and IMR-32 cells.

PubMed Central

Verstraeten, Sandra V; Zago, M Paola; MacKenzie, Gerardo G; Keen, Carl L; Oteiza, Patricia I

2004-01-01

We investigated whether zinc deficiency can affect plasma membrane rheology. Three cell lines, human leukaemia T-cells (Jurkat), rat fibroblasts (3T3) and human neuroblastoma cells (IMR-32), were cultured for 48 h in control medium, in zinc-deficient medium (1.5 microM zinc; 1.5 Zn), or in the zinc-deficient medium supplemented with 15 microM zinc (15 Zn). The number of viable cells was lower in the 1.5 Zn group than in the control and 15 Zn groups. The frequency of apoptosis was higher in the 1.5 Zn group than in the control and 15 Zn groups. Membrane fluidity was evaluated using the 6-(9-anthroyloxy)stearic acid and 16-(9-anthroyloxy)palmitic acid probes. Membrane fluidity was higher in 1.5 Zn cells than in the control cells; no differences were observed between control cells and 15 Zn cells. The effect of zinc deficiency on membrane fluidity at the water/lipid interface was associated with a higher phosphatidylserine externalization. The higher membrane fluidity in the hydrophobic region of the bilayer was correlated with a lower content of arachidonic acid. We suggest that the increased fluidity of the membrane secondary to zinc deficiency is in part due to a decrease in arachidonic acid content and the apoptosis-related changes in phosphatidylserine distribution. PMID:14629198

Antagonism between granulocytic maturation and deacetylase inhibitor-induced apoptosis in acute promyelocytic leukaemia cells.

PubMed

Hennig, D; Müller, S; Wichmann, C; Drube, S; Pietschmann, K; Pelzl, L; Grez, M; Bug, G; Heinzel, T; Krämer, O H

2015-01-20

Transcriptional repression is a key mechanism driving leukaemogenesis. In acute promyelocytic leukaemia (APL), the fusion protein promyelocytic leukaemia-retinoic acid receptor-α fusion (PML-RARα) recruits transcriptional repressors to myeloid differentiation genes. All-trans-retinoic acid (ATRA) induces the proteasomal degradation of PML-RARα and granulocytic differentiation. Histone deacetylases (HDACs) fall into four classes (I-IV) and contribute to the transcription block caused by PML-RARα. Immunoblot, flow cytometry, and May-Grünwald-Giemsa staining were used to analyze differentiation and induction of apoptosis. A PML-RARα- and ATRA-dependent differentiation programme induces granulocytic maturation associated with an accumulation of the myeloid transcription factor CCAAT/enhancer binding protein (C/EBP)ɛ and of the surface protein CD11b. While this process protects APL cells from inhibitors of class I HDAC activity, inhibition of all Zinc-dependent HDACs (classes I, II, and IV) with the pan-HDACi (histone deacetylase inhibitor(s)) LBH589 induces apoptosis of immature and differentiated APL cells. LBH589 can eliminate C/EBPɛ and the mitochondrial apoptosis regulator B-cell lymphoma (BCL)-xL in immature and differentiated NB4 cells. Thus, BCL-xL and C/EBPɛ are newly identified molecular markers for the efficacy of HDACi against APL cells. Our results could explain the therapeutic limitations occurring with ATRA and class I HDACi combinations. Pro-apoptotic effects caused by pan-HDAC inhibition are not blunted by ATRA-induced differentiation and may provide a clinically interesting alternative.

Alemtuzumab in T-cell large granular lymphocytic leukaemia: interim results from a single-arm, open-label, phase 2 study.

PubMed

Dumitriu, Bogdan; Ito, Sawa; Feng, Xingmin; Stephens, Nicole; Yunce, Muharrem; Kajigaya, Sachiko; Melenhorst, Joseph J; Rios, Olga; Scheinberg, Priscila; Chinian, Fariba; Keyvanfar, Keyvan; Battiwalla, Minoo; Wu, Colin O; Maric, Irina; Xi, Liqiang; Raffeld, Mark; Muranski, Pawel; Townsley, Danielle M; Young, Neal S; Barrett, Austin J; Scheinberg, Phillip

2016-01-01

T-cell large granular lymphocytic leukaemia (T-LGL) is a lymphoproliferative disease that presents with immune-mediated cytopenias and is characterised by clonal expansion of cytotoxic CD3+ CD8+ lymphocytes. Use of methotrexate, ciclosporin, or cyclophosphamide as first therapy improves cytopenias in 50% of patients, but long-term use of these can lead to toxicity. We aimed to explore the activity and safety of alemtuzumab, an anti-CD52 monoclonal antibody, in patients with T-LGL. We did this single-arm, phase 2 trial in consecutively enrolled adults with T-LGL referred to the National Institutes of Health in Bethesda, MD, USA. Alemtuzumab was given intravenously at 10 mg per day for 10 days. The primary endpoint was haematological response at 3 months after infusion. A complete response was defined as normalisation of all affected lineages, and a partial response was defined in neutropenic patients as 100% increase in the absolute neutrophil count to more than 5 × 10(8) cells per L, and in those with anaemia, as any increase in haemoglobin of 20 g/L or higher observed in at least two serial measurements 1 week apart and sustained for 1 month or longer without exogenous growth factors support or transfusions. Analysis was by intention to treat. We report results from the first stage of this Simon two-stage design trial; enrolment into the second stage is continuing. This study is registered with ClinicalTrials.gov, number NCT00345345. From Oct 1, 2006, to March 1, 2015, we enrolled 25 patients with T-LGL. 14 patients (56%; 95% CI 35-76) had a haematological response at 3 months. Four patients with associated myelodysplastic syndrome and two who had received haemopoietic stem cell transplantation had either no response or were not evaluable, meaning 14 (74% [49-91]) of the 19 patients with classic T-LGL responded. All patients had an infusion reaction (24 [96%] patients grade 1-2, one [4%] patient grade 3), which improved with symptomatic therapy. All

Targeting SYK kinase-dependent anti-apoptotic resistance pathway in B-lineage acute lymphoblastic leukaemia (ALL) cells with a potent SYK inhibitory pentapeptide mimic.

PubMed

Uckun, Fatih M; Ek, Rauf O; Jan, Shyi-Tai; Chen, Chun-Lin; Qazi, Sanjive

2010-05-01

The present study found that the pentapeptide mimic C-61, targeting the substrate binding P-site of SYK tyrosine kinase acted as a potent inducer of apoptosis in chemotherapy-resistant SYK-expressing primary leukemic B-cell precursors taken directly from relapsed B-precursor leukaemia (BPL) patients (but not SYK-deficient infant pro-B leukaemia cells), exhibited favourable pharmacokinetics in mice and non-human primates, and eradicated in vivo clonogenic leukaemia cells in severe combined immunodeficient mouse xenograft models of chemotherapy-resistant human BPL at dose levels non-toxic to mice and non-human primates. These in vitro and in vivo findings provide proof of principle for effective treatment of chemotherapy-resistant BPL by targeting SYK-dependent anti-apoptotic blast cell survival machinery with a SYK P-Site inhibitor. Further development of C-61 may provide the foundation for therapeutic innovation against chemotherapy-resistant BPL.

Effect of interleukins on the proliferation and survival of B cell chronic lymphocytic leukaemia cells.

PubMed Central

Mainou-Fowler, T; Copplestone, J A; Prentice, A G

1995-01-01

AIMS--To investigate the effects of interleukin (IL) 1, 2, 4, and 5 on the proliferation and survival of peripheral blood B cells from patients with B chronic lymphocytic leukaemia (B-CLL) and compare them with the effects on normal peripheral blood B cells. METHODS--The proliferation and survival of pokeweed mitogen (PWM) activated B cells from B-CLL (n = 12) and normal peripheral blood (n = 5) were studied in vitro in response to IL-1, IL-2 IL-4, and IL-5. Survival of cells in cultures with or without added interleukins was studied by microscopic examination of cells and DNA agarose gel electrophoresis. RESULTS--Proliferation was observed in both B-CLL and normal peripheral blood cells on culture with IL-2 alone and also in some, but not all, B-CLL and normal peripheral blood cells with IL-1 and IL-4. However, there was greater variability in B-CLL cell responses than in normal peripheral blood cells. Il-5 did not affect normal peripheral blood cell proliferation but it increased proliferation in two B-CLL cases. Synergistic effects of these cytokines were not detected. IL-4 inhibited normal peripheral blood and B-CLL cell proliferation after the addition of IL-2. Inhibition of B-CLL cell responses to IL-2 was also observed with IL-5 and Il-1. Survival of B-CLL cells in cultures was enhanced with IL-4 not by an increase in proliferation but by reduced apoptosis. No such effect was seen in normal peripheral blood cells. IL-2 had a less noticeable antiapoptotic effect; IL-5 enhanced apoptosis in B-CLL cells. CONCLUSIONS--B-CLL and normal peripheral blood cells proliferated equally well in response to IL-2. IL-4 had a much lower effect on B-CLL cell proliferation, but had noticeable antiapoptotic activity. IL-5 enhanced cell death by apoptosis. Images PMID:7629299

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

Ibrutinib (Imbruvica). Relapsed chronic lymphocytic leukaemia and mantle cell lymphoma: uncertain impact on survival.

PubMed

January

2016-04-01

codynamic interactions are also likely in view of its adverse effect profile. There is no consensus on the treatment of patients with refractory or relapsed mantle cell lymphoma, or for patients with relapsed or possibly refractory chronic lymphocytic leukaemia. Ibrutinib inhibits an enzyme involved in regulating B lymphocyte activity. It has been authorised in the European Union for these conditions. Clinical evaluation of ibrutinib in mantle cell lymphoma is based on a single non-comparative trial in 111 patients, in which the median overall survival time was 22.5 months. Clinical evaluation of ibrutinib in chronic lymphocytic leukaemia is based on two randomised trials. One unblinded trial compared ibrutinib versus ofatumumab and involved 391 patients, most of whom were sufficiently fit to receive anticancer combination therapy. Ibrutinib was more effective than ofatumumab, but the choice of this comparator might not have been appropriate for most of the patients who received it. The other double-blind, placebo-controlled trial involved 578 patients with relapsed or refractory chronic lymphocytic leukaemia. Ibrutinib was added to the bendamustine + rituximab combination. No significant difference in mortality was observed between the two groups. The main adverse effects of ibrutinib were: gastrointestinal disorders such as diarrhoea; life-threatening infections and bleeding disorders; and cardiac disorders, including atrial fibrillation. Ibrutinib carries a risk of multiple pharmacokinetic interactions. Pharmacodynamic interactions are also likely in view of its adverse effect profile.

Distinct homotypic B-cell receptor interactions shape the outcome of chronic lymphocytic leukaemia

PubMed Central

Minici, Claudia; Gounari, Maria; Übelhart, Rudolf; Scarfò, Lydia; Dühren-von Minden, Marcus; Schneider, Dunja; Tasdogan, Alpaslan; Alkhatib, Alabbas; Agathangelidis, Andreas; Ntoufa, Stavroula; Chiorazzi, Nicholas; Jumaa, Hassan; Stamatopoulos, Kostas; Ghia, Paolo; Degano, Massimo

2017-01-01

Cell-autonomous B-cell receptor (BcR)-mediated signalling is a hallmark feature of the neoplastic B lymphocytes in chronic lymphocytic leukaemia (CLL). Here we elucidate the structural basis of autonomous activation of CLL B cells, showing that BcR immunoglobulins initiate intracellular signalling through homotypic interactions between epitopes that are specific for each subgroup of patients with homogeneous clinicobiological profiles. The molecular details of the BcR–BcR interactions apparently dictate the clinical course of disease, with stronger affinities and longer half-lives in indolent cases, and weaker, short-lived contacts mediating the aggressive ones. The diversity of homotypic BcR contacts leading to cell-autonomous signalling reconciles the existence of a shared pathogenic mechanism with the biological and clinical heterogeneity of CLL and offers opportunities for innovative treatment strategies. PMID:28598442

Naja nigricollis CMS-9 enhances the mitochondria-mediated death pathway in adaphostin-treated human leukaemia U937 cells.

PubMed

Chen, Ying-Jung; Wang, Jeh-Jeng; Chang, Long-Sen

2011-11-01

1. The aim of the present study was to explore the effect of the Naja nigricollis phospholipase A(2) CMS-9 on adaphostin-induced death of human leukaemia U937 cells. 2. Leukaemia U937 cells (Bcr/Abl-negative cells) were treated with adaphostin (0-10 μmol/L) and CMS-9 (0-1 μmol/L). The effects of CMS-9, adaphostin and their combination on cell viability, the generation reactive oxygen species (ROS), [Ca(2+) ](i) , p38 mitogen-activated protein kinase (MAPK) activation, Akt and extracellular signal-regulated kinase (ERK) inactivation, mitochondrial membrane potential (ΔΨ(m) ) and Bcl-2 family proteins were analysed. 3. Both adaphostin and CMS-9 induced U937 cell apoptosis, characterized by dissipation of ΔΨ(m) and ROS generation. Combined treatment further increased ΔΨ(m) loss and reduced the viability of adaphostin-treated cells. Unlike in CMS-9-treated cells, in adaphostin-treated cells ROS-induced increases in [Ca(2+) ](i) were observed. CMS-9-induced ROS generation resulted in p38 MAPK activation, whereas adaphostin treatment elicited ROS/Ca(2+) -mediated inactivation of Akt and ERK. Moreover, Akt was found to be involved in ERK phosphorylation. Suppression of p38 MAPK activation blocked CMS-9-induced ΔΨ(m) loss and Bcl-xL downregulation. Overexpression of constitutively active Akt and mitogen-activated protein kinase kinase (MEK) 1 rescued adaphostin-induced ΔΨ(m) loss and Bcl-2 downregulation. Similarly, CMS-9 augmented adaphostin toxicity in human leukaemia K562 cells via increased mitochondrial alterations. 4. The results suggest that two distinct pathways mediate adaphostin- and CMS-9-induced mitochondrial damage (i.e. the ROS-Ca(2+) -Akt-ERK and ROS-p38 MAPK pathways, respectively). These distinct pathway explain the augmentation by CMS-9 of ΔΨ(m) loss and apoptosis in adaphostin-treated U937 cells. © 2011 The Authors. Clinical and Experimental Pharmacology and Physiology © 2011 Blackwell Publishing Asia Pty Ltd.

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.

Identification of pre-leukaemic haematopoietic stem cells in acute leukaemia.

PubMed

Shlush, Liran I; Zandi, Sasan; Mitchell, Amanda; Chen, Weihsu Claire; Brandwein, Joseph M; Gupta, Vikas; Kennedy, James A; Schimmer, Aaron D; Schuh, Andre C; Yee, Karen W; McLeod, Jessica L; Doedens, Monica; Medeiros, Jessie J F; Marke, Rene; Kim, Hyeoung Joon; Lee, Kwon; McPherson, John D; Hudson, Thomas J; Brown, Andrew M K; Yousif, Fouad; Trinh, Quang M; Stein, Lincoln D; Minden, Mark D; Wang, Jean C Y; Dick, John E

2014-02-20

In acute myeloid leukaemia (AML), the cell of origin, nature and biological consequences of initiating lesions, and order of subsequent mutations remain poorly understood, as AML is typically diagnosed without observation of a pre-leukaemic phase. Here, highly purified haematopoietic stem cells (HSCs), progenitor and mature cell fractions from the blood of AML patients were found to contain recurrent DNMT3A mutations (DNMT3A(mut)) at high allele frequency, but without coincident NPM1 mutations (NPM1c) present in AML blasts. DNMT3A(mut)-bearing HSCs showed a multilineage repopulation advantage over non-mutated HSCs in xenografts, establishing their identity as pre-leukaemic HSCs. Pre-leukaemic HSCs were found in remission samples, indicating that they survive chemotherapy. Therefore DNMT3A(mut) arises early in AML evolution, probably in HSCs, leading to a clonally expanded pool of pre-leukaemic HSCs from which AML evolves. Our findings provide a paradigm for the detection and treatment of pre-leukaemic clones before the acquisition of additional genetic lesions engenders greater therapeutic resistance.

EBV-Positive Lymphoproliferations of B- T- and NK-Cell Derivation in Non-Immunocompromised Hosts

PubMed Central

Fend, Falko

2018-01-01

The contribution of Epstein-Barr virus (EBV) to the development of specific types of benign lymphoproliferations and malignant lymphomas has been extensively studied since the discovery of the virus over the last 50 years. The importance and better understanding of the EBV-associated lymphoproliferative disorders (LPD) of B, T or natural killer (NK) cell type has resulted in the recognition of new entities like EBV+ mucocutaneous ulcer or the addition of chronic active EBV (CAEBV) infection in the revised 2016 World Health Organization (WHO) lymphoma classification. In this article, we review the definitions, morphology, pathogenesis, and evolving concepts of the various EBV-associated disorders including EBV+ diffuse large B-cell lymphoma, not otherwise specified (DLBCL, NOS), EBV+ mucocutaneous ulcer, DLBCL associated with chronic inflammation, fibrin-associated DLBCL, lymphomatoid granulomatosis, the EBV+ T and NK-cell LPD of childhood, aggressive NK leukaemia, extranodal NK/T-cell lymphoma, nasal type, and the new provisional entity of primary EBV+ nodal T- or NK-cell lymphoma. The current knowledge regarding the pathogenesis of B-cell lymphomas that can be EBV-associated including Burkitt lymphoma, plasmablastic lymphoma and classic Hodgkin lymphoma will be also explored. PMID:29518976

Effects of pharmacological and genetic disruption of CXCR4 chemokine receptor function in B-cell acute lymphoblastic leukaemia.

PubMed

Randhawa, Shubhchintan; Cho, Byung S; Ghosh, Dipanjan; Sivina, Mariela; Koehrer, Stefan; Müschen, Markus; Peled, Amnon; Davis, Richard E; Konopleva, Marina; Burger, Jan A

2016-08-01

B cell acute lymphoblastic leukaemia (B-ALL) cells express high levels of CXCR4 chemokine receptors for homing and retention within the marrow microenvironment. Bone marrow stromal cells (BMSC) secrete CXCL12, the ligand for CXCR4, and protect B-ALL cells from cytotoxic drugs. Therefore, the therapeutic use of CXCR4 antagonists has been proposed to disrupt cross talk between B-ALL cells and the protective stroma. Because CXCR4 antagonists can have activating agonistic function, we compared the genetic and pharmacological deletion of CXCR4 in B-ALL cells, using CRISPR-Cas9 gene editing and CXCR4 antagonists that are in clinical use (plerixafor, BKT140). Both genetic and pharmacological CXCR4 inhibition significantly reduced B-ALL cell migration to CXCL12 gradients and beneath BMSC, and restored drug sensitivity to dexamethasone, vincristine and cyclophosphamide. NOD/SCID/IL-2rγnull mice injected with CXCR4 gene-deleted B-ALL cells had significant delay in disease progression and superior survival when compared to control mice injected with CXCR4 wild-type B-ALL cells. These findings indicate that anti-leukaemia activity of CXCR4 antagonists is primarily due to CXCR4 inhibition, rather than agonistic activity, and corroborate that CXCR4 is an important target to overcome stroma-mediated drug resistance in B-ALL. © 2016 John Wiley & Sons Ltd.

Lck is a relevant target in chronic lymphocytic leukaemia cells whose expression variance is unrelated to disease outcome.

PubMed

Till, Kathleen J; Allen, John C; Talab, Fatima; Lin, Ke; Allsup, David; Cawkwell, Lynn; Bentley, Alison; Ringshausen, Ingo; Duckworth, Andrew D; Pettitt, Andrew R; Kalakonda, Nagesh; Slupsky, Joseph R

2017-12-01

Pathogenesis of chronic lymphocytic leukaemia (CLL) is contingent upon antigen receptor (BCR) expressed by malignant cells of this disease. Studies on somatic hypermutation of the antigen binding region, receptor expression levels and signal capacity have all linked BCR on CLL cells to disease prognosis. Our previous work showed that the src-family kinase Lck is a targetable mediator of BCR signalling in CLL cells, and that variance in Lck expression associated with ability of BCR to induce signal upon engagement. This latter finding makes Lck similar to ZAP70, another T-cell kinase whose aberrant expression in CLL cells also associates with BCR signalling capacity, but also different because ZAP70 is not easily pharmacologically targetable. Here we describe a robust method of measuring Lck expression in CLL cells using flow cytometry. However, unlike ZAP70 whose expression in CLL cells predicts prognosis, we find Lck expression and disease outcome in CLL are unrelated despite observations that its inhibition produces effects that biologically resemble the egress phenotype taken on by CLL cells treated with idelalisib. Taken together, our findings provide insight into the pathobiology of CLL to suggest a more complex relationship between expression of molecules within the BCR signalling pathway and disease outcome.

Pharmacologic suppression of target cell recognition by engineered T cells expressing chimeric T-cell receptors.

PubMed

Alvarez-Vallina, L; Yañez, R; Blanco, B; Gil, M; Russell, S J

2000-04-01

Adoptive therapy with autologous T cells expressing chimeric T-cell receptors (chTCRs) is of potential interest for the treatment of malignancy. To limit possible T-cell-mediated damage to normal tissues that weakly express the targeted tumor antigen (Ag), we have tested a strategy for the suppression of target cell recognition by engineered T cells. Jurkat T cells were transduced with an anti-hapten chTCR tinder the control of a tetracycline-suppressible promoter and were shown to respond to Ag-positive (hapten-coated) but not to Ag-negative target cells. The engineered T cells were then reacted with hapten-coated target cells at different effector to target cell ratios before and after exposure to tetracycline. When the engineered T cells were treated with tetracycline, expression of the chTCR was greatly decreased and recognition of the hapten-coated target cells was completely suppressed. Tetracycline-mediated suppression of target cell recognition by engineered T cells may be a useful strategy to limit the toxicity of the approach to cancer gene therapy.

An investigation of the effect of antisense RNA gene on bovine leukaemia virus reproduction in cell culture.

PubMed

Murovska, M F; Chernobayeva, L G; Miroshnichenko, O I; Tomsons, V P; Konicheva, V V; Ivanova, S V; Tikhonenko, T I

1992-11-01

A possible approach to control of bovine lymphoproliferative disease caused by bovine leukaemia virus (BLV) may be the development of an "antiviral information immunity" based on the effect of anti-sense RNA (asRNA). A numbers of constructs were obtained, under control of various promotors (herpesvirus thymidine kinase, T-antigen SV40 promoter), carrying as DNA against gene X, the expression product of which is a transactivator of viral transcription from the BLV LTR promotor. As a model system for the analysis of antiviral activity of constructs developed, cloned continuous cell lines of BLV-producing FLK cells were used. The level of BLV expression in cells transfected with the constructs was determined by various parameters. Differences were detected in different clones obtained from non-transfected cells, as well as variation between transfected clones, as measured by reverse transcriptase, competitive radio-immunoassay for BLV p24, the viral particle count on agar membrane, and the tumorigenicity for nude mice. The differences in inhibition of expression of BLV genes and their products may be explained in terms of the site of integration of asDNA and the number of integrated copies.

Third-generation CD28/4-1BB chimeric antigen receptor T cells for chemotherapy relapsed or refractory acute lymphoblastic leukaemia: a non-randomised, open-label phase I trial protocol.

PubMed

Tang, Xiao-Yi; Sun, Yao; Zhang, Ang; Hu, Guo-Liang; Cao, Wei; Wang, Dan-Hong; Zhang, Bin; Chen, Hu

2016-12-30

There is no curative treatment available for patients with chemotherapy relapsed or refractory CD19+ B cells-derived acute lymphoblastic leukaemia (r/r B-ALL). Although CD19-targeting second-generation (2nd-G) chimeric antigen receptor (CAR)-modified T cells carrying CD28 or 4-1BB domains have demonstrated potency in patients with advanced B-ALL, these 2 signalling domains endow CAR-T cells with different and complementary functional properties. Preclinical results have shown that third-generation (3rd-G) CAR-T cells combining 4-1BB and CD28 signalling domains have superior activation and proliferation capacity compared with 2nd-G CAR-T cells carrying CD28 domain. The aim of the current study is therefore to investigate the safety and efficacy of 3rd-G CAR-T cells in adults with r/r B-ALL. This study is a phase I clinical trial for patients with r/r B-ALL to test the safety and preliminary efficacy of 3rd-G CAR-T cells. Before receiving lymphodepleting conditioning regimen, the peripheral blood mononuclear cells from eligible patients will be leukapheresed, and the T cells will be purified, activated, transduced and expanded ex vivo. On day 6 in the protocol, a single dose of 1 million CAR-T cells per kg will be administrated intravenously. The phenotypes of infused CAR-T cells, copy number of CAR transgene and plasma cytokines will be assayed for 2 years after CAR-T infusion using flow cytometry, real-time quantitative PCR and cytometric bead array, respectively. Moreover, several predictive plasma cytokines including interferon-γ, interleukin (IL)-6, IL-8, Soluble Interleukin (sIL)-2R-α, solubleglycoprotein (sgp)130, sIL-6R, Monocyte chemoattractant protein (MCP1), Macrophage inflammatory protein (MIP1)-α, MIP1-β and Granulocyte-macrophage colony-stimulating factor (GM-CSF), which are highly associated with severe cytokine release syndrome (CRS), will be used to forecast CRS to allow doing earlier intervention, and CRS will be managed based on a revised CRS

Antibody therapy for acute myeloid leukaemia.

PubMed

Gasiorowski, Robin E; Clark, Georgina J; Bradstock, Kenneth; Hart, Derek N J

2014-02-01

Novel therapies with increased efficacy and decreased toxicity are desperately needed for the treatment of acute myeloid leukaemia (AML). The anti CD33 immunoconjugate, gemtuzumab ozogamicin (GO), was withdrawn with concerns over induction mortality and lack of efficacy. However a number of recent trials suggest that, particularly in AML with favourable cytogenetics, GO may improve overall survival. This data and the development of alternative novel monoclonal antibodies (mAb) have renewed interest in the area. Leukaemic stem cells (LSC) are identified as the subset of AML blasts that reproduces the leukaemic phenotype upon transplantation into immunosuppressed mice. AML relapse may be caused by chemoresistant LSC and this has refocused interest on identifying and targeting antigens specific for LSC. Several mAb have been developed that target LSC effectively in xenogeneic models but only a few have begun clinical evaluation. Antibody engineering may improve the activity of potential new therapeutics for AML. The encouraging results seen with bispecific T cell-engaging mAb-based molecules against CD19 in the treatment of B-cell acute lymphobalstic leukaemia, highlight the potential efficacy of engineered antibodies in the treatment of acute leukaemia. Potent engineered mAb, possibly targeting novel LSC antigens, offer hope for improving the current poor prognosis for AML. © 2013 John Wiley & Sons Ltd.

Targeting survival pathways in chronic myeloid leukaemia stem cells

PubMed Central

Sinclair, A; Latif, A L; Holyoake, T L

2013-01-01

Chronic myeloid leukaemia (CML) is a clonal myeloproliferative disorder characterized by the presence of a fusion oncogene BCR-ABL, which encodes a protein with constitutive TK activity. The implementation of tyrosine kinase inhibitors (TKIs) marked a major advance in CML therapy; however, there are problems with current treatment. For example, relapse occurs when these drugs are discontinued in the majority of patients who have achieved a complete molecular response on TKI and these agents are less effective in patients with mutations in the BCR-ABL kinase domain. Importantly, TKI can effectively target proliferating mature cells, but do not eradicate quiescent leukaemic stem cells (LSCs), therefore allowing disease persistence despite treatment. It is essential that alternative strategies are used to target the LSC population. BCR-ABL activation is responsible for the modulation of different signalling pathways, which allows the LSC fraction to evade cell death. Several pathways have been shown to be modulated by BCR-ABL, including PI3K/AKT/mTOR, JAK-STAT and autophagy signalling pathways. Targeting components of these survival pathways, alone or in combination with TKI, therefore represents an attractive potential therapeutic approach for targeting the LSC. However, many pathways are also active in normal stem cells. Therefore, potential targets must be validated to effectively eradicate CML stem cells while sparing normal counterparts. This review summarizes the main pathways modulated in CML stem cells, the recent developments and the use of novel drugs to target components in these pathways which may be used to target the LSC population. Linked Articles This article is part of a themed section on Emerging Therapeutic Aspects in Oncology. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.169.issue-8 PMID:23517124

CMC-544 (inotuzumab ozogamicin) shows less effect on multidrug resistant cells: analyses in cell lines and cells from patients with B-cell chronic lymphocytic leukaemia and lymphoma.

PubMed

Takeshita, Akihiro; Shinjo, Kaori; Yamakage, Nozomi; Ono, Takaaki; Hirano, Isao; Matsui, Hirotaka; Shigeno, Kazuyuki; Nakamura, Satoki; Tobita, Tadasu; Maekawa, Masato; Ohnishi, Kazunori; Sugimoto, Yoshikazu; Kiyoi, Hitoshi; Naoe, Tomoki; Ohno, Ryuzo

2009-06-01

The effect of CMC-544, a calicheamicin-conjugated anti-CD22 monoclonal antibody, was analysed in relation to CD22 and P-glycoprotein (P-gp) in B-cell chronic lymphocytic leukaemia (CLL) and non-Hodgkin lymphoma (NHL) in vitro. The cell lines used were CD22-positive parental Daudi and Raji, and their P-gp positive sublines, Daudi/MDR and Raji/MDR. Cells obtained from 19 patients with B-cell CLL or NHL were also used. The effect of CMC-544 was analysed by viable cell count, morphology, annexin-V staining, and cell cycle distribution. A dose-dependent, selective cytotoxic effect of CMC-544 was observed in cell lines that expressed CD22. CMC-544 was not effective on Daudi/MDR and Raji/MDR cells compared with their parental cells. The MDR modifiers, PSC833 and MS209, restored the cytotoxic effect of CMC-544 in P-gp-expressing sublines. In clinical samples, the cytotoxic effect of CMC-544 was inversely related to the amount of P-gp (P = 0.003), and to intracellular rhodamine-123 accumulation (P < 0.001). On the other hand, the effect positively correlated with the amount of CD22 (P = 0.010). The effect of CMC-544 depends on the levels of CD22 and P-gp. Our findings will help to predict the clinical effectiveness of this drug on these B-cell malignancies, suggesting a beneficial effect with combined use of CMC-544 and MDR modifiers.

Klinefelter syndrome and acute basophilic leukaemia--case report.

PubMed

Ljubić, Nives; Lang, Nada; Skelin, Ika Kardum; Lasan, Ruzica; Dominis, Mara; Perković, Leila; Zupanić-Krmek, Dubraka; Grgurević-Batinica, Anita

2010-06-01

Patients with 47, XXY karyotype (Klinefelter syndrome) appear to have increased risk of developing cancer, especially male breast cancer, germ cell tumours and non Hodgkin lymphomas, but rarely acute myeloid leukaemia. We report a patient with acute basophilic leukaemia with 47, XXY karyotype in both the tumour and constitutional cells. Acute basophilic leukaemia is very rare disease comprising less than 1% of all acute myeloid leukaemias. Morphological characteristic of leukaemic blast cells is moderately basophilic cytoplasm containing a variable number of coarse basophilic granules. The most characteristic cytochemical reaction is metachromatic positivity with toluidine blue. Blast are myeloperoxidase negative. Also leukemic blasts express myeloid and monocyte markers. There is no consistent chromosomal abnormality identified in this leukaemia. This is the first reported case of acute basophilic leukaemia in patient with Klinefelter syndrome. In this article the medical history of the patient is given and the possible connection between Klinefelter syndrome and acute myeloid leukaemia is discussed.

Violacein Induces Death of Resistant Leukaemia Cells via Kinome Reprogramming, Endoplasmic Reticulum Stress and Golgi Apparatus Collapse

PubMed Central

Queiroz, Karla C. S.; Milani, Renato; Ruela-de-Sousa, Roberta R.; Fuhler, Gwenny M.; Justo, Giselle Z.; Zambuzzi, Willian F.; Duran, Nelson; Diks, Sander H.; Spek, C. Arnold; Ferreira, Carmen V.; Peppelenbosch, Maikel P.

2012-01-01

It is now generally recognised that different modes of programmed cell death (PCD) are intimately linked to the cancerous process. However, the mechanism of PCD involved in cancer chemoprevention is much less clear and may be different between types of chemopreventive agents and tumour cell types involved. Therefore, from a pharmacological view, it is crucial during the earlier steps of drug development to define the cellular specificity of the candidate as well as its capacity to bypass dysfunctional tumoral signalling pathways providing insensitivity to death stimuli. Studying the cytotoxic effects of violacein, an antibiotic dihydro-indolone synthesised by an Amazon river Chromobacterium, we observed that death induced in CD34+/c-Kit+/P-glycoprotein+/MRP1+ TF1 leukaemia progenitor cells is not mediated by apoptosis and/or autophagy, since biomarkers of both types of cell death were not significantly affected by this compound. To clarify the working mechanism of violacein, we performed kinome profiling using peptide arrays to yield comprehensive descriptions of cellular kinase activities. Pro-death activity of violacein is actually carried out by inhibition of calpain and DAPK1 and activation of PKA, AKT and PDK, followed by structural changes caused by endoplasmic reticulum stress and Golgi apparatus collapse, leading to cellular demise. Our results demonstrate that violacein induces kinome reprogramming, overcoming death signaling dysfunctions of intrinsically resistant human leukaemia cells. PMID:23071514

Antitumour effects of single or combined monoclonal antibodies directed against membrane antigens expressed by human B cells leukaemia

PubMed Central

2011-01-01

Background The increasing availability of different monoclonal antibodies (mAbs) opens the way to more specific biologic therapy of cancer patients. However, despite the significant success of therapy in breast and ovarian carcinomas with anti-HER2 mAbs as well as in non-Hodkin B cell lymphomas with anti-CD20 mAbs, certain B cell malignancies such as B chronic lymphocytic leukaemia (B-CLL) respond poorly to anti-CD20 mAb, due to the low surface expression of this molecule. Thus, new mAbs adapted to each types of tumour will help to develop personalised mAb treatment. To this aim, we analyse the biological and therapeutic properties of three mAbs directed against the CD5, CD71 or HLA-DR molecules highly expressed on B-CLL cells. Results The three mAbs, after purification and radiolabelling demonstrated high and specific binding capacity to various human leukaemia target cells. Further in vitro analysis showed that mAb anti-CD5 induced neither growth inhibition nor apoptosis, mAb anti-CD71 induced proliferation inhibition with no early sign of cell death and mAb anti-HLA-DR induced specific cell aggregation, but without evidence of apoptosis. All three mAbs induced various degrees of ADCC by NK cells, as well as phagocytosis by macrophages. Only the anti-HLA-DR mAb induced complement mediated lysis. Coincubation of different pairs of mAbs did not significantly modify the in vitro results. In contrast with these discrete and heterogeneous in vitro effects, in vivo the three mAbs demonstrated marked anti-tumour efficacy and prolongation of mice survival in two models of SCID mice, grafted either intraperitoneally or intravenously with the CD5 transfected JOK1-5.3 cells. This cell line was derived from a human hairy cell leukaemia, a type of malignancy known to have very similar biological properties as the B-CLL, whose cells constitutively express CD5. Interestingly, the combined injection of anti-CD5 with anti-HLA-DR or with anti-CD71 led to longer mouse survival, as

Mast cells enhance T cell activation: Importance of mast cell-derived TNF

NASA Astrophysics Data System (ADS)

Nakae, Susumu; Suto, Hajime; Kakurai, Maki; Sedgwick, Jonathon D.; Tsai, Mindy; Galli, Stephen J.

2005-05-01

Mast cells are not only important effector cells in immediate hypersensitivity reactions and immune responses to pathogens but also can contribute to T cell-mediated disorders. However, the mechanisms by which mast cells might influence T cells in such settings are not fully understood. We find that mast cells can enhance proliferation and cytokine production in multiple T cell subsets. Mast cell-dependent enhancement of T cell activation can be promoted by FcRI-dependent mast cell activation, TNF production by both mast cells and T cells, and mast cell-T cell contact. However, at high concentrations of cells, mast cells can promote T cell activation independent of IgE or TNF. Finally, mast cells also can promote T cell activation by means of soluble factors. These findings identify multiple mechanisms by which mast cells can influence T cell proliferation and cytokine production. allergy | asthma | autoimmunity | cytokines | immune response

Co-occurrence of biphenotypic acute leukaemia, glucose 6-phosphate dehydrogenase deficiency and haemoglobin E trait in a single child.

PubMed

Mallick, Debkrishna; Thapa, Rajoo; Biswas, Biswajit

2016-02-01

Acute leukaemias occur as the result of clonal expansion subsequent to transformation and arrest at a normal differentiation stage of haematopoietic precursors, which commit to a single lineage, such as myeloid or B-lymphoid or T-lymphoid cells. Biphenotypic acute leukaemia (BAL) constitutes a biologically different group of leukaemia arising from a precursor stem cell and co-expressing more than one lineage specific marker. The present report describes a child with unusual co-occurrence of biphenotypic (B-precursor cell and Myeloid) acute leukaemia, haemoglobin E trait and glucose 6-phosphate dehydrogenase (G6-PD) deficiency. To the best of our knowledge, this constellation of haematological conditions in a single child has never been described before. 2016 BMJ Publishing Group Ltd.

Heterozygote FANCD2 mutations associated with childhood T Cell ALL and testicular seminoma.

PubMed

Smetsers, Stephanie; Muter, Joanne; Bristow, Claire; Patel, Leena; Chandler, Kate; Bonney, Denise; Wynn, Robert F; Whetton, Anthony D; Will, Andrew M; Rockx, Davy; Joenje, Hans; Strathdee, Gordon; Shanks, Jonathan; Klopocki, Eva; Gille, Johan J P; Dorsman, Josephine; Meyer, Stefan

2012-12-01

Fanconi anaemia (FA) is an inherited disease with congenital and developmental abnormalities characterised by cellular cross linker hypersensitivity. FA is caused by mutations in any of so far 15 identified FANC genes, which encode proteins that interact in a common DNA damage response (DDR) pathway. Individuals with FA have a high risk of developing acute myeloid leukaemia (AML) and squamous cell carcinoma. An increased cancer risk has been firmly established for carriers of mutations in FANCD1/BRCA2, FANCJ/BRIP1, FANCN/PALB2, RAD51C/FANCO and link the FA pathway to inherited breast and ovarian cancer. We describe a pedigree with FANCD2 mutations c.458T > C (p.Leu153Ser) and c.2715 + 1G > A (p.Glu906LeufsX4) with mild phenotype FA in the index case, T cell ALL in the Leu153Ser heterozygous brother and testicular seminoma in the p.Glu906LeufsX4 heterozygous father. Both FANCD2 alleles were present in the T Cell ALL and the seminoma. This links specific FANCD2 mutations to T cell ALL and seminoma without evidence of allelic loss in the tumour tissue.

T-cell help permits memory CD8(+) T-cell inflation during cytomegalovirus latency.

PubMed

Walton, Senta M; Torti, Nicole; Mandaric, Sanja; Oxenius, Annette

2011-08-01

CD4(+) T cells are implied to sustain CD8(+) T-cell responses during persistent infections. As CD4(+) T cells are often themselves antiviral effectors, they might shape CD8(+) T-cell responses via help or via controlling antigen load. We used persistent murine CMV (MCMV) infection to dissect the impact of CD4(+) T cells on virus-specific CD8(+) T cells, distinguishing between increased viral load in the absence of CD4(+) T cells and CD4(+) T-cell-mediated helper mechanisms. Absence of T-helper cells was associated with sustained lytic MCMV replication and led to a slow and gradual reduction of the size and function of the MCMV-specific CD8(+) T-cell pool. However, when virus replication was controlled in the absence of CD4(+) T cells, CD8(+) T-cell function was comparably impaired, but in addition CD8(+) T-cell inflation, a hallmark of CMV infection, was completely abolished. Thus, CD8(+) T-cell inflation during latent CMV infection is strongly dependent on CD4(+) T-cell helper functions, which can partially be compensated by ongoing lytic viral replication in the absence of CD4(+) T cells. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

[Regulatory T cells].

PubMed

Marinić, Igor; Gagro, Alenka; Rabatić, Sabina

2006-12-01

Regulatory T-cells are a subset of T cells that have beene extensively studied in modern immunology. They are important for the maintenance of peripheral tolerance, and have an important role in various clinical conditions such as allergy, autoimmune disorders, tumors, infections, and in transplant medicine. Basically, this population has a suppressive effect on the neighboring immune cells, thus contributing to the local modulation and control of immune response. There are two main populations of regulatory T cells - natural regulatory T cells, which form a distinct cellular lineage, develop in thymus and perform their modulatory action through direct intercellular contact, along with the secreted cytokines; and inducible regulatory T cells, which develop in the periphery after contact with the antigen that is presented on the antigen presenting cell, and their primary mode of action is through the interleukin 10 (IL-10) and transforming growth factor beta (TGF-alpha) cytokines. Natural regulatory T cells are activated through T cell receptor after contact with specific antigen and inhibit proliferation of other T cells in an antigen independent manner. One of the major difficulties in the research of regulatory T cells is the lack of specific molecular markers that would identify these cells. Natural regulatory T cells constitutively express surface molecule CD25, but many other surface and intracellular molecules (HLA-DR, CD122, CD45RO, CD62, CTLA-4, GITR, PD-1, Notch, FOXP3, etc.) are being investigated for further phenotypic characterization of these cells. Because regulatory T cells have an important role in establishing peripheral tolerance, their importance is manifested in a number of clinical conditions. In the IPEX syndrome (immunodysregulation, polyendocrinopathy and enteropathy, X-linked), which is caused by mutation in Foxp3 gene that influences the development and function of regulatory T cells, patients develop severe autoimmune reactions that

γδ T cell homeostasis is established in competition with αβ T cells and NK cells

PubMed Central

French, Jena D.; Roark, Christina L.; Born, Willi K.; O'Brien, Rebecca L.

2005-01-01

γδ T cells are a diverse population of lymphocytes that play an important role in immune regulation. The size of the γδ T cell pool is tightly regulated, comprising only 1-10% of total lymphoid T cells in mice and humans. We examined the homeostatic regulation of γδ T cells using a model of lymphopenia-induced homeostatic expansion. We found that IL-15 and, to a lesser extent, IL-7 play an important role in lymphoid γδ T cell homeostasis. Moreover, γδ T cell homeostatic expansion was limited not only by γδ T cells themselves but also by natural killer cells and αβ T cells. Our results suggest that CD8+ αβ T cells are the most potent inhibitors of γδ T cell homeostasis and exert their effect by competing for IL-15. PMID:16203967

Dipeptide species regulate p38MAPK–Smad3 signalling to maintain chronic myelogenous leukaemia stem cells

PubMed Central

Naka, Kazuhito; Jomen, Yoshie; Ishihara, Kaori; Kim, Junil; Ishimoto, Takahiro; Bae, Eun-Jin; Mohney, Robert P.; Stirdivant, Steven M.; Oshima, Hiroko; Oshima, Masanobu; Kim, Dong-Wook; Nakauchi, Hiromitsu; Takihara, Yoshihiro; Kato, Yukio; Ooshima, Akira; Kim, Seong-Jin

2015-01-01

Understanding the specific survival of the rare chronic myelogenous leukaemia (CML) stem cell population could provide a target for therapeutics aimed at eradicating these cells. However, little is known about how survival signalling is regulated in CML stem cells. In this study, we survey global metabolic differences between murine normal haematopoietic stem cells (HSCs) and CML stem cells using metabolomics techniques. Strikingly, we show that CML stem cells accumulate significantly higher levels of certain dipeptide species than normal HSCs. Once internalized, these dipeptide species activate amino-acid signalling via a pathway involving p38MAPK and the stemness transcription factor Smad3, which promotes CML stem cell maintenance. Importantly, pharmacological inhibition of dipeptide uptake inhibits CML stem cell activity in vivo. Our results demonstrate that dipeptide species support CML stem cell maintenance by activating p38MAPK–Smad3 signalling in vivo, and thus point towards a potential therapeutic target for CML treatment. PMID:26289811

Mechanosensitive cation channels in human leukaemia cells: calcium permeation and blocking effect

PubMed Central

Staruschenko, Alexandr V; Vedernikova, Elena A

2002-01-01

Cell-attached and inside-out patch-clamp methods were employed to identify and characterize mechanosensitive (MS) ionic channels in the plasma membrane of human myeloid leukaemia K562 cells. A reversible activation of gadolinium-blockable mechanogated currents in response to negative pressure application was found in 58 % of stable patches (n = 317). I-V relationships measured with a sodium-containing pipette solution showed slight inward rectification. Data analysis revealed the presence of two different populations of channels that were distinguishable by their conductance properties (17.2 ± 0.3 pS and 24.5 ± 0.5 pS), but were indistinguishable with regard to their selective and pharmacological properties. Ion-substitution experiments indicated that MS channels in leukaemia cells were permeable to cations but not to anions and do not discriminate between Na+ and K+. The channels were fully impermeable to large organic cations such as Tris+ and N-methyl-d-glucamine ions (NMDG+). Ca2+ permeation and blockade of MS channels were examined using pipettes containing different concentrations of Ca2+. In the presence of 2 mm CaCl2, when other cations were impermeant, both outward and inward single-channel currents were observed; the I-V relationship showed a unitary conductance of 7.7 ± 1.0 pS. The relative permeability value, PCa/PK, was equal to 0.75, as estimated at physiological Ca2+ concentrations. Partial or full inhibition of inward Ca2+ currents through MS channels was observed at higher concentrations of external Ca2+ (10 or 20 mm). No MS channels were activated when using a pipette containing 90 mm CaCl2. Monovalent mechanogated currents were not significantly affected by extracellular Ca2+ at concentrations within the physiological range (0-2 mm), and at some higher Ca2+ concentrations. PMID:12015421

The bruton tyrosine kinase inhibitor ibrutinib (PCI-32765) blocks hairy cell leukaemia survival, proliferation and B cell receptor signalling: a new therapeutic approach.

PubMed

Sivina, Mariela; Kreitman, Robert J; Arons, Evgeny; Ravandi, Farhad; Burger, Jan A

2014-07-01

B cell receptor (BCR) signalling plays a critical role in the progression of several B-cell malignancies, but its role in hairy cell leukaemia (HCL) is ambiguous. Bruton tyrosine kinase (BTK), a key player in BCR signalling, as well as B cell migration and adhesion, can be targeted with ibrutinib, a selective, irreversible BTK inhibitor. We analysed BTK expression and function in HCL and analysed the effects of ibrutinib on HCL cells. We demonstrated uniform BTK protein expression in HCL cells. Ibrutinib significantly inhibited HCL proliferation and cell cycle progression. Accordingly, ibrutinib also reduced HCL cell survival after BCR triggering with anti-immunoglobulins and abrogated the activation of kinases downstream of the BCR (PI3K and MAPK). Ibrutinib also inhibited BCR-dependent secretion of the chemokines CCL3 and CCL4 by HCL cells. Interestingly, ibrutinib inhibited also CXCL12-induced signalling, a key pathway for bone marrow homing. Collectively, our data support the clinical development of ibrutinib in patients with HCL. © 2014 John Wiley & Sons Ltd.

5'-Triphosphate siRNA targeting MDR1 reverses multi-drug resistance and activates RIG-I-induced immune-stimulatory and apoptotic effects against human myeloid leukaemia cells.

PubMed

Li, Dengzhe; Gale, Robert Peter; Liu, Yanfeng; Lei, Baoxia; Wang, Yuan; Diao, Dongmei; Zhang, Mei

2017-07-01

Multi-drug resistance (MDR), immune suppression and decreased apoptosis are important causes of therapy-failure in leukaemia. Short interfering RNAs (siRNAs) down-regulate gene transcription, have sequence-independent immune-stimulatory effects and synergize with other anti-cancer therapies in some experimental models. We designed a siRNA targeting MDR1 with 5'-triphosphate ends (3p-siRNA-MDR1). Treatment of leukaemia cells with 3p-siRNA-MDR1 down-regulated MDR1 expression, reduced-drug resistance and induced immune and pro-apoptotic effects in drug-resistant HL-60/Adr and K562/Adr human leukaemia cell lines. We show mechanisms-of-action of these effects involve alterations in the anti-viral cytosolic retinoic acid-inducible protein-I (RIG-I; encoded by RIG-I or DDX58) mediated type-I interferon signal induction, interferon-gamma-inducible protein 10 (IP-10; encoded by IP10 or CXCL10) secretion, major histocompatibility complex-I expression (MHC-I) and caspase-mediated cell apoptosis. 3p-siRNA-MDR1 transfection also enhanced the anti-leukaemia efficacy of doxorubicin. These data suggest a possible synergistic role for 3p-siRNA-MDR1 in anti-leukaemia therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

T-cell receptor transfer into human T cells with ecotropic retroviral vectors.

PubMed

Koste, L; Beissert, T; Hoff, H; Pretsch, L; Türeci, Ö; Sahin, U

2014-05-01

Adoptive T-cell transfer for cancer immunotherapy requires genetic modification of T cells with recombinant T-cell receptors (TCRs). Amphotropic retroviral vectors (RVs) used for TCR transduction for this purpose are considered safe in principle. Despite this, TCR-coding and packaging vectors could theoretically recombine to produce replication competent vectors (RCVs), and transduced T-cell preparations must be proven free of RCV. To eliminate the need for RCV testing, we transduced human T cells with ecotropic RVs so potential RCV would be non-infectious for human cells. We show that transfection of synthetic messenger RNA encoding murine cationic amino-acid transporter 1 (mCAT-1), the receptor for murine retroviruses, enables efficient transient ecotropic transduction of human T cells. mCAT-1-dependent transduction was more efficient than amphotropic transduction performed in parallel, and preferentially targeted naive T cells. Moreover, we demonstrate that ecotropic TCR transduction results in antigen-specific restimulation of primary human T cells. Thus, ecotropic RVs represent a versatile, safe and potent tool to prepare T cells for the adoptive transfer.

Gene expression analysis of murine cells producing amphotropic mouse leukaemia virus at a cultivation temperature of 32 and 37 degrees C.

PubMed

Beer, Christiane; Buhr, Petra; Hahn, Heidi; Laubner, Daniela; Wirth, Manfred

2003-07-01

Cultivation of retrovirus packaging cells at 32 degrees C represents a common procedure to achieve high titres in mouse retrovirus production. Gene expression profiling of mouse NIH 3T3 cells producing amphotropic mouse leukaemia virus 4070A revealed that 10 % of the 1176 cellular genes investigated were regulated by temperature shift (37/32 degrees C), while 5 % were affected by retrovirus infection. Strikingly, retrovirus production at 32 degrees C activated the cholesterol biosynthesis/transport pathway and caused an increase in plasma membrane cholesterol levels. Furthermore, these conditions resulted in transcriptional activation of smoothened (smo), patched (ptc) and gli-1; Smo, Ptc and Gli-1, as well as cholesterol, are components of the Sonic hedgehog (Shh) signalling pathway, which directs pattern formation, diversification and tumourigenesis in mammalian cells. These findings suggest a link between cultivation at 32 degrees C, production of MLV-A and the Shh signalling pathway.

Infiltration of γ⁢δ T cells, IL-17+ T cells and FoxP3+ T cells in human breast cancer

PubMed Central

Allaoui, Roni; Hagerling, Catharina; Desmond, Eva; Warfvinge, Carl-Fredrik; Jirström, Karin; Leandersson, Karin

2017-01-01

BACKGROUND: Tumor-infiltrating lymphocytes (TILs) have a strong prognostic value in various forms of cancers. These data often refer to use of the pan-T cell marker CD3, or the cytotoxic T lymphocyte marker CD8α. However, T cells are a heterogeneous group of cells with a wide array of effector mechanisms ranging from immunosuppression to cytotoxicity. OBJECTIVE: In this study we have investigated the prognostic effects of some unconventional T cell subtypes in breast cancer; γ⁢δ T cells, IL-17+ T cells and FoxP3+ T cells (Tregs) in relation to the conventional CD3 and CD8α T cell markers. METHODS: This was done using immunohistochemistry on a human breast cancer tissue microarray consisting of 498 consecutive cases of primary breast cancer. RESULTS: Infiltration of γ⁢δ T cells and T cell infiltration in general (CD3), correlated with a good prognosis, while Treg infiltration with a worse. Infiltration of γ⁢δ T cells was associated with a significantly improved clinical outcome in all breast cancer subtypes except triple negative tumors. Only infiltration of either CD3+ or CD8α+ cells was independently associated with better prognosis for all breast cancer patients. CONCLUSIONS: This study sheds further light on the prognostic impact of various T cell subtypes in breast cancer. PMID:29060923

CD45RA, a specific marker for leukaemia stem cell sub-populations in acute myeloid leukaemia.

PubMed

Kersten, Bas; Valkering, Matthijs; Wouters, Rolf; van Amerongen, Rosa; Hanekamp, Diana; Kwidama, Zinia; Valk, Peter; Ossenkoppele, Gert; Zeijlemaker, Wendelien; Kaspers, Gertjan; Cloos, Jacqueline; Schuurhuis, Gerrit J

2016-04-01

Chemotherapy resistant leukaemic stem cells (LSC) are thought to be responsible for relapses after therapy in acute myeloid leukaemia (AML). Flow cytometry can discriminate CD34(+) CD38(-) LSC and normal haematopoietic stem cells (HSC) by using aberrant expression of markers and scatter properties. However, not all LSC can be identified using currently available markers, so new markers are needed. CD45RA is expressed on leukaemic cells in the majority of AML patients. We investigated the potency of CD45RA to specifically identify LSC and HSC and improve LSC quantification. Compared to our best other markers (CLL-1, also termed CLEC12A, CD33 and CD123), CD45RA was the most reliable marker. Patients with high percentages (>90%) of CD45RA on CD34(+) CD38(-) LSC have 1·69-fold higher scatter values compared to HSC (P < 0·001), indicating a more mature CD34(+) CD38(-) phenotype. Patients with low (<10%) or intermediate (10-90%) CD45RA expression on LSC showed no significant differences to HSC (1·12- and 1·15-fold higher, P = 0·31 and P = 0·44, respectively). CD45RA-positive LSC tended to represent more favourable cytogenetic/molecular markers. In conclusion, CD45RA contributes to more accurate LSC detection and is recommended for inclusion in stem cell tracking panels. CD45RA may contribute to define new LSC-specific therapies and to monitor effects of anti-LSC treatment. © 2016 John Wiley & Sons Ltd.

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.

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.

Cell surface expression of beta 2-microglobulin (beta 2m) correlates with stages of differentiation in B cell tumours.

PubMed Central

Jones, R A; Scott, C S; Norfolk, D R; Stark, A N; Child, J A

1987-01-01

Cell surface beta 2-microglobulin (beta 2m) densities of malignant B cells were determined by enzyme immunoassay in 97 cases of immunologically defined lymphoproliferative disease. Absolute beta 2m densities were found to depend on disease category with the lowest levels found on cells from chronic lymphocytic leukaemia (mean = 5.6 ng/10(6) cells, n = 27); atypical chronic lymphocytic leukaemia (mean = 5.9 ng/10(6) cells, n = 8); and prolymphocytoid chronic lymphocytic leukaemia variant (mean = 6.0 ng/10(6) cells, n = 16). beta 2m densities for B non-Hodgkin's lymphoma (n = 14) and B prolymphocytic leukaemia (n = 17) cases were 8.1 and 10.0 ng/10(6) cells, respectively, and the highest densities were found on cells from "late-B cell" tumours (mean = 14.3 ng/10(6) cells). Plasma cells from cases of Ig secreting tumours expressed unexpectedly low beta 2m densities (mean = 9.3 ng/10(6) cells; n = 6). PMID:3108331

The signaling symphony: T cell receptor tunes cytokine-mediated T cell differentiation

PubMed Central

Huang, Weishan; August, Avery

2015-01-01

T cell development, differentiation, and maintenance are orchestrated by 2 key signaling axes: the antigen-specific TCR and cytokine-mediated signals. The TCR signals the recognition of self- and foreign antigens to control T cell homeostasis for immune tolerance and immunity, which is regulated by a variety of cytokines to determine T cell subset homeostasis and differentiation. TCR signaling can synergize with or antagonize cytokine-mediated signaling to fine tune T cell fate; however, the latter is less investigated. Murine models with attenuated TCR signaling strength have revealed that TCR signaling can function as regulatory feedback machinery for T cell homeostasis and differentiation in differential cytokine milieus, such as IL-2-mediated Treg development; IL-7-mediated, naïve CD8+ T cell homeostasis; and IL-4-induced innate memory CD8+ T cell development. In this review, we discuss the symphonic cross-talk between TCR and cytokine-mediated responses that differentially control T cell behavior, with a focus on the negative tuning by TCR activation on the cytokine effects. PMID:25525115

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.

In vitro generation of helper T cells and suppressor T cells that regulate the cytolytic T lymphocyte response to trinitrophenyl-modified syngeneic cells.

PubMed

Gualde, N; Weinberger, O; Ratnofsky, S; Benacerraf, B; Burakoff, S J

1982-04-01

Helper T cells and suppressor T cells have been generated in vitro that regulate the cytolytic T lymphocyte (CTL) response to trinitrophenyl (TNP)-modified syngeneic cells. B6D2F1 helper cells generated to TNP-modified parental (P1) cells augment the CTL response to those P1-TNP-modified antigens but not to P2-TNP-modified antigens. The generation of these helper T cells requires the presence of splenic adherent cells and these helper T cells are radioresistant. A soluble factor can be obtained from the helper T cell cultures that can also augment the CTL response. The suppressor T cells generated in culture do not demonstrate the specificity observed with the helper T cells; however, they are antigen-dependent in their induction. Whether helper or suppressor activity is obtained depends upon the length of time cells are cultured in vitro.

In vitro generation of helper T cells and suppressor T cells that regulate the cytolytic T lymphocyte response to trinitrophenyl-modified syngeneic cells

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

Gualde, N.; Weinberger, O.; Ratnofsky, S.

1982-04-01

Helper T cells and suppressor T cells have been generated in vitro that regulate the cytolytic T lymphocyte (CTL) response to trinitrophenyl (TNP)-modified syngeneic cells. B6D2F1 helper cells generated to TNP-modified parental (P1) cells augment the CTL response to those P1-TNP-modified antigens but not to P2-TNP-modified antigens. The generation of these helper T cells requires the presence of splenic adherent cells and these helper T cells are radioresistant. A soluble factor can be obtained from the helper T cell cultures that can also augment the CTL response. The suppressor T cells generated in culture do not demonstrate the specificity observedmore » with the helper T cells; however, they are antigen-dependent in their induction. Whether helper or suppressor activity is obtained depends upon the length of time cells are cultured in vitro.« less

Dendritic cell internalization of α-galactosylceramide from CD8 T cells induces potent antitumor CD8 T-cell responses.

PubMed

Choi, Dong Hoon; Kim, Kwang Soon; Yang, Se Hwan; Chung, Doo Hyun; Song, Boyeong; Sprent, Jonathan; Cho, Jae Ho; Sung, Young Chul

2011-12-15

Dendritic cells (DC) present α-galactosylceramide (αGalCer) to invariant T-cell receptor-expressing natural killer T cells (iNKT) activating these cells to secrete a variety of cytokines, which in turn results in DC maturation and activation of other cell types, including NK cells, B cells, and conventional T cells. In this study, we showed that αGalCer-pulsing of antigen-activated CD8 T cells before adoptive transfer to tumor-bearing mice caused a marked increase in donor T-cell proliferation, precursor frequency, and cytotoxic lymphocyte activity. This effect was interleukin (IL)-2 dependent and involved both natural killer T cells (NKT) and DCs, as mice lacking IL-2, NKTs, and DCs lacked any enhanced response to adoptively transferred αGalCer-loaded CD8 T cells. iNKT activation was mediated by transfer of αGalCer from the cell membrane of the donor CD8 T cells onto the αGalCer receptor CD1d which is present on host DCs. αGalCer transfer was increased by prior activation of the donor CD8 T cells and required AP-2-mediated endocytosis by host DCs. In addition, host iNKT cell activation led to strong IL-2 synthesis, thereby increasing expansion and differentiation of donor CD8 T cells. Transfer of these cells led to improved therapeutic efficacy against established solid tumors in mice. Thus, our findings illustrate how αGalCer loading of CD8 T cells after antigen activation in vitro may leverage the therapeutic potential of adoptive T-cell therapies.

Production and first-in-man use of T cells engineered to express a HSVTK-CD34 sort-suicide gene.

PubMed

Zhan, Hong; Gilmour, Kimberly; Chan, Lucas; Farzaneh, Farzin; McNicol, Anne Marie; Xu, Jin-Hua; Adams, Stuart; Fehse, Boris; Veys, Paul; Thrasher, Adrian; Gaspar, Hubert; Qasim, Waseem

2013-01-01

Suicide gene modified donor T cells can improve immune reconstitution after allogeneic haematopoietic stem cell transplantation (SCT), but can be eliminated in the event of graft versus host disease (GVHD) through the administration of prodrug. Here we report the production and first-in-man use of mismatched donor T cells modified with a gamma-retroviral vector expressing a herpes simplex thymidine kinase (HSVTK):truncated CD34 (tCD34) suicide gene/magnetic selection marker protein. A stable packaging cell line was established to produce clinical grade vector pseudotyped with the Gibbon Ape Leukaemia Virus (GALV). T cells were transduced in a closed bag system following activation with anti-CD3/CD28 beads, and enriched on the basis of CD34 expression. Engineered cells were administered in two escalating doses to three children receiving T-depleted, CD34 stem cell selected, mismatched allogeneic grafts. All patients had pre-existing viral infections and received chemotherapy conditioning without serotherapy. In all three subjects cell therapy was tolerated without acute toxicity or the development of acute GVHD. Circulating gene modified T cells were detectable by flow cytometry and by molecular tracking in all three subjects. There was resolution of virus infections, concordant with detectable antigen-specific T cell responses and gene modified cells persisted for over 12 months. These findings highlight the suitability of tCD34 as a GMP compliant selection marker and demonstrate the feasibility, safety and immunological potential of HSVTK-tCD34 suicide gene modified donor T cells. ClinicalTrials.gov NCT01204502

ArtinM Mediates Murine T Cell Activation and Induces Cell Death in Jurkat Human Leukemic T Cells

PubMed Central

Oliveira-Brito, Patrícia Kellen Martins; Gonçalves, Thiago Eleutério; Vendruscolo, Patrícia Edivânia; Roque-Barreira, Maria Cristina

2017-01-01

The recognition of cell surface glycans by lectins may be critical for the innate and adaptive immune responses. ArtinM, a d-mannose-binding lectin from Artocarpus heterophyllus, activates antigen-presenting cells by recognizing TLR2 N-glycans and induces Th1 immunity. We recently demonstrated that ArtinM stimulated CD4+ T cells to produce proinflammatory cytokines. Here, we further studied the effects of ArtinM on adaptive immune cells. We showed that ArtinM activates murine CD4+ and CD8+ T cells, augmenting their positivity for CD25, CD69, and CD95 and showed higher interleukin (IL)-2 and interferon (IFN)-γ production. The CD4+ T cells exhibited increased T-bet expression in response to ArtinM, and IL-2 production by CD4+ and CD8+ T cells depended on the recognition of CD3εγ-chain glycans by ArtinM. The ArtinM effect on aberrantly-glycosylated neoplastic lymphocytes was studied in Jurkat T cells, in which ArtinM induced IL-2, IFN-γ, and IL-1β production, but decreased cell viability and growth. A higher frequency of AnnexinV- and propidium iodide-stained cells demonstrated the induction of Jurkat T cells apoptosis by ArtinM, and this apoptotic response was reduced by caspases and protein tyrosine kinase inhibitors. The ArtinM effects on murine T cells corroborated with the immunomodulatory property of lectin, whereas the promotion of Jurkat T cells apoptosis may reflect a potential applicability of ArtinM in novel strategies for treating lymphocytic leukemia. PMID:28665310

Selective bispecific T cell recruiting antibody and antitumor activity of adoptive T cell transfer.

PubMed

Kobold, Sebastian; Steffen, Julius; Chaloupka, Michael; Grassmann, Simon; Henkel, Jonas; Castoldi, Raffaella; Zeng, Yi; Chmielewski, Markus; Schmollinger, Jan C; Schnurr, Max; Rothenfußer, Simon; Schendel, Dolores J; Abken, Hinrich; Sustmann, Claudio; Niederfellner, Gerhard; Klein, Christian; Bourquin, Carole; Endres, Stefan

2015-01-01

One bottleneck for adoptive T cell therapy (ACT) is recruitment of T cells into tumors. We hypothesized that combining tumor-specific T cells, modified with a marker antigen and a bispecific antibody (BiAb) that selectively recognizes transduced T cells and tumor cells would improve T cell recruitment to tumors and enhance therapeutic efficacy. SV40 T antigen-specific T cells from T cell receptor (TCR)-I-transgenic mice were transduced with a truncated human epidermal growth factor receptor (EGFR) as a marker protein. Targeting and killing by combined ACT and anti-EGFR-anti-EpCAM BiAb therapy was analyzed in C57Bl/6 mice (n = six to 12 per group) carrying subcutaneous tumors of the murine gastric cancer cell line GC8 (SV40(+) and EpCAM(+)). Anti-EGFR x anti-c-Met BiAb was used for targeting of human tumor-specific T cells to c-Met(+) human tumor cell lines. Differences between experimental conditions were analyzed using the Student's t test, and differences in tumor growth with two-way analysis of variance. Overall survival was analyzed by log-rank test. All statistical tests were two-sided. The BiAb linked EGFR-transduced T cells to tumor cells and enhanced tumor cell lysis. In vivo, the combination of ACT and Biab produced increased T cell infiltration of tumors, retarded tumor growth, and prolonged survival compared with ACT with a control antibody (median survival 95 vs 75 days, P < .001). In human cells, this strategy enhanced recruitment of human EGFR-transduced T cells to immobilized c-Met and recognition of tyrosinase(+) melanoma cells by TCR-, as well as of CEA(+) colon cancer cells by chimeric antigen receptor (CAR)-modified T cells. BiAb recruitment of tumor-specific T cells transduced with a marker antigen to tumor cells may enhance efficacy of ACT. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Understanding the reconstitution of the B-cell compartment in bone marrow and blood after treatment for B-cell precursor acute lymphoblastic leukaemia.

PubMed

Theunissen, Prisca M J; van den Branden, Anouk; Van Der Sluijs-Gelling, Alita; De Haas, Valerie; Beishuizen, Auke; van Dongen, Jacques J M; Van Der Velden, Vincent H J

2017-07-01

A better understanding of the reconstitution of the B-cell compartment during and after treatment in B-cell precursor acute lymphoblastic leukaemia (BCP-ALL) will help to assess the immunological status and needs of post-treatment BCP-ALL patients. Using 8-colour flow cytometry and proliferation-assays, we studied the composition and proliferation of both the B-cell precursor (BCP) population in the bone marrow (BM) and mature B-cell population in peripheral blood (PB) during and after BCP-ALL therapy. We found a normal BCP differentiation pattern and a delayed formation of classical CD38 dim -naive mature B-cells, natural effector B-cells and memory B-cells in patients after chemotherapy. This B-cell differentiation/maturation pattern was strikingly similar to that during initial B-cell development in healthy infants. Tissue-resident plasma cells appeared to be partly protected from chemotherapy. Also, we found that the fast recovery of naive mature B-cell numbers after chemotherapy was the result of increased de novo BCP generation, rather than enhanced B-cell proliferation in BM or PB. These results indicate that post-treatment BCP-ALL patients will eventually re-establish a B-cell compartment with a composition and B-cell receptor repertoire similar to that in healthy children. Additionally, the formation of a new memory B-cell compartment suggests that revaccination might be beneficial after BCP-ALL therapy. © 2017 John Wiley & Sons Ltd.

Transcriptional and functional defects of dendritic cells derived from the MUTZ-3 leukaemia line

PubMed Central

Rasaiyaah, Jane; Noursadeghi, Mahdad; Kellam, Paul; Chain, Benjamin

2009-01-01

Dendritic cells (DC) generated from MUTZ-3, an immortalized acute myeloid leukaemia-derived cell line, have potential application as a model for the study of human DC, and as a tool with which to stimulate immunotherapeutic responses to cancer. However, the relationship of MUTZ-3 DC to their non-transformed counterparts remains incompletely understood. Immunoselected CD14+ MUTZ-3 cells were used to generate a homogeneous population of DC (M3DC). These cells had a cell surface phentoype and morphology characteristic of conventional monocyte-derived DC (MDDC). Whole genome transcriptome comparison of M3DC and MDDC however, revealed extensive differences between these two cell types. Functional ontology-based data analysis revealed three enriched clusters of genes downregulated in M3DC, with functions in pathogen recognition, DC maturation and cytokine/chemokine signalling. Downregulation of protein expression was confirmed for several of these genes. The molecular differences were accompanied by a profoundly impaired phenotypic and functional response of M3DC to microbial stimulation. The immortalized phenotype of MUTZ-3 therefore reflects not only deregulated proliferative capacity, but substantial perturbation of normal antigen-presenting cell function. These results have important implications for studies using MUTZ-3 as a model of MDDC or for cancer immunotherapy. PMID:19538250

Targeted therapy with MXD3 siRNA, anti-CD22 antibody and nanoparticles for precursor B-cell acute lymphoblastic leukaemia.

PubMed

Satake, Noriko; Duong, Connie; Chen, Cathy; Barisone, Gustavo A; Diaz, Elva; Tuscano, Joseph; Rocke, David M; Nolta, Jan; Nitin, Nitin

2014-11-01

Conventional chemotherapy for precursor B-cell (preB) acute lymphoblastic leukaemia (ALL) has limitations that could be overcome by targeted therapy. Previously, we discovered a potential therapeutic molecular target, MDX3 (MAX dimerization protein 3), in preB ALL. In this study, we hypothesize that an effective siRNA therapy for preB ALL can be developed using antiCD22 antibody (αCD22 Ab) and nanoparticles. We composed nanocomplexes with super paramagnetic iron oxide nanoparticles (SPIO NPs), αCD22 Abs and MXD3 siRNA molecules based on physical interactions between the molecules. We demonstrated that the MXD3 siRNA-αCD22 Ab-SPIO NP complexes entered leukaemia cells and knocked down MXD3, leading the cells to undergo apoptosis and resulting in decreased live cell counts in the cell line Reh and in primary preB ALL samples in vitro. Furthermore, the cytotoxic effects of the MXD3 siRNA-αCD22 Ab-SPIO NP complexes were significantly enhanced by addition of the chemotherapy drugs vincristine or doxorubicin. We also ruled out potential cytotoxic effects of the MXD3 siRNA-αCD22 Ab-SPIO NP complexes on normal primary haematopoietic cells. Normal B cells were affected while CD34-positive haematopoietic stem cells and non-B cells were not. These data suggest that MXD3 siRNA-αCD22 Ab-SPIO NP complexes have the potential to be a new targeted therapy for preB ALL. © 2014 John Wiley & Sons Ltd.

SL-401 and SL-501, Targeted Therapeutics Directed at the Interleukin-3 Receptor, Inhibit the Growth of Leukaemic Cells and Stem Cells in Advanced Phase Chronic Myeloid Leukaemia

PubMed Central

Frolova, Olga; Benito, Juliana; Brooks, Chris; Wang, Rui-Yu; Korchin, Borys; Rowinsky, Eric K.; Cortes, Jorge; Kantarjian, Hagop; Andreeff, Michael; Frankel, Arthur E.; Konopleva, Marina

2014-01-01

SUMMARY While imatinib and other tyrosine kinase inhibitors (TKIs) are highly efficacious in the treatment of chronic myeloid leukaemia (CML), some patients become refractory to these therapies. After confirming that interleukin-3 receptor (IL3R, CD123) is highly expressed on CD34+/CD38− BCR-ABL1+ CML stem cells, we investigated whether targeting IL3R with diphtheria toxin (DT)-IL3 fusion proteins SL-401 (DT388-IL3) and SL-501 (DT388-IL3[K116W]) could eradicate these stem cells. SL-401 and SL-501 inhibited cell growth and induced apoptosis in the KBM5 cell line and its TKI-resistant KBM5-STI subline. Combinations of imatinib with these agents increased apoptosis in KBM5 and in primary CML cells. In six primary CML samples, including CML cells harbouring the ABL1 T315I mutation, SL-401 and SL-501 decreased the absolute numbers of viable CD34+/CD38−/CD123+ CML progenitor cells by inducing apoptosis. IL3-targeting agents reduced clonogenic growth and diminished the fraction of primitive long-term culture-initiating cells in samples from patients with advanced phase CML that were resistant to TKIs or harboured an ABL1 mutation. Survival was also extended in a mouse model of primary TKI-resistant CML blast crisis. These data suggest that the DT-IL3 fusion proteins, SL-401 and SL-501, deplete CML stem cells and may increase the effectiveness of current CML treatment, which principally targets tumour bulk. PMID:24942980

SL-401 and SL-501, targeted therapeutics directed at the interleukin-3 receptor, inhibit the growth of leukaemic cells and stem cells in advanced phase chronic myeloid leukaemia.

PubMed

Frolova, Olga; Benito, Juliana; Brooks, Chris; Wang, Rui-Yu; Korchin, Borys; Rowinsky, Eric K; Cortes, Jorge; Kantarjian, Hagop; Andreeff, Michael; Frankel, Arthur E; Konopleva, Marina

2014-09-01

While imatinib and other tyrosine kinase inhibitors (TKIs) are highly efficacious in the treatment of chronic myeloid leukaemia (CML), some patients become refractory to these therapies. After confirming that interleukin-3 receptor (IL3R, CD123) is highly expressed on CD34(+) /CD38(-) BCR-ABL1(+) CML stem cells, we investigated whether targeting IL3R with diphtheria toxin (DT)-IL3 fusion proteins SL-401 (DT388 -IL3) and SL-501 (DT388 -IL3[K116W]) could eradicate these stem cells. SL-401 and SL-501 inhibited cell growth and induced apoptosis in the KBM5 cell line and its TKI-resistant KBM5-STI subline. Combinations of imatinib with these agents increased apoptosis in KBM5 and in primary CML cells. In six primary CML samples, including CML cells harbouring the ABL1 T315I mutation, SL-401 and SL-501 decreased the absolute numbers of viable CD34(+) /CD38(-) /CD123(+) CML progenitor cells by inducing apoptosis. IL3-targeting agents reduced clonogenic growth and diminished the fraction of primitive long-term culture-initiating cells in samples from patients with advanced phase CML that were resistant to TKIs or harboured an ABL1 mutation. Survival was also extended in a mouse model of primary TKI-resistant CML blast crisis. These data suggest that the DT-IL3 fusion proteins, SL-401 and SL-501, deplete CML stem cells and may increase the effectiveness of current CML treatment, which principally targets tumour bulk. © 2014 John Wiley & Sons Ltd.

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.

Specific T-cell activation in an unspecific T-cell repertoire.

PubMed

Van Den Berg, Hugo A; Molina-París, Carmen; Sewell, Andrew K

2011-01-01

T-cells are a vital type of white blood cell that circulate around our bodies, scanning for cellular abnormalities and infections. They recognise disease-associated antigens via a surface receptor called the T-cell antigen receptor (TCR). If there were a specific TCR for every single antigen, no mammal could possibly contain all the T-cells it needs. This is clearly absurd and suggests that T-cell recognition must, to the contrary, be highly degenerate. Yet highly promiscuous TCRs would appear to be equally impossible: they are bound to recognise self as well as non-self antigens. We review how contributions from mathematical analysis have helped to resolve the paradox of the promiscuous TCR. Combined experimental and theoretical work shows that TCR degeneracy is essentially dynamical in nature, and that the T-cell can differentially adjust its functional sensitivity to the salient epitope, "tuning up" sensitivity to the antigen associated with disease and "tuning down" sensitivity to antigens associated with healthy conditions. This paradigm of continual modulation affords the TCR repertoire, despite its limited numerical diversity, the flexibility to respond to almost any antigenic challenge while avoiding autoimmunity.

Secondary pure erythroid leukaemia in relapsed acute lymphoblastic leukaemia: lineage switch or chemotherapy effect?

PubMed

Gupta, Sanjeev Kumar; Kumar, Rajive; Chharchhodawala, Taher; Kumar, Lalit

2014-05-19

Pure erythroid leukaemia is a rare subtype of acute myeloid leukaemia (AML) and its occurrence at acute lymphoblastic leukaemia (ALL) relapse has not been reported earlier. A 39-year-old man received chemotherapy for Philadelphia-negative B cell ALL. Subsequently, he developed pure erythroid leukaemia with >80% immature erythroid precursors in bone marrow showing block positivity on periodic acid-Schiff stain, expressing CD71, CD34 but lacking CD235a. The interval between exposure to multidrug chemotherapy including cyclophosphamide and AML diagnosis was 2 years and 9 months. No cytogenetic abnormality was detected at the time of relapse. The patient died 2 weeks after starting AML chemotherapy. The relatively narrow time interval (usually 5-10 years) between chemotherapy and AML development and normal karyotype at relapse raises a possibility of lineage switch besides therapy-related AML as the likely pathogenesis. Further exploration of such cases may unravel the pathways responsible for lineage assignment in pluripotent stem cells. 2014 BMJ Publishing Group Ltd.

Clinical utility of next-generation sequencing-based minimal residual disease in paediatric B-cell acute lymphoblastic leukaemia.

PubMed

Sekiya, Yuko; Xu, Yinyan; Muramatsu, Hideki; Okuno, Yusuke; Narita, Atsushi; Suzuki, Kyogo; Wang, Xinan; Kawashima, Nozomu; Sakaguchi, Hirotoshi; Yoshida, Nao; Hama, Asahito; Takahashi, Yoshiyuki; Kato, Koji; Kojima, Seiji

2017-01-01

We assessed the clinical utility of next-generation sequencing (NGS)-based monitoring of minimal residual disease (MRD) in a uniformly treated cohort of 79 patients with paediatric B-cell acute lymphoblastic leukaemia. Bone marrow samples were collected at the time of diagnosis, days 33 and 80, pre- (4-5 months) and post- (24 months) maintenance therapy time points, and at relapse. We identified leukaemia-specific CDR3 sequences in 72 of 79 patients (91%) and detected MRD in 59 of 232 samples. Although MRD was detected in 28 of 55 samples (51%) on day 33, the frequencies of MRD detection decreased to 25% (16/65) at day 80, 19% (11/58) at 4-5 months and 7·4% (4/54) at 24 months. In a univariate analysis, positive MRD results on day 80 [relative risk (RR) 95% confidence interval (CI) = 7·438 (2·561-21·6), P < 0·001], at 4-5 months [RR (95% CI) = 10·24 (3·374-31·06), P < 0·001], and at 24 months [RR (95% CI) = 19·26 (4·974-74·59), P < 0·001] exhibited statistically significant associations with inferior leukaemia-free survival; this was confirmed using a Cox proportional hazard model. Our study suggests the promising potential of NGS-MRD for patients with B-cell ALL. © 2016 John Wiley & Sons Ltd.

A T-cell-directed chimeric antigen receptor for the selective treatment of T-cell malignancies.

PubMed

Mamonkin, Maksim; Rouce, Rayne H; Tashiro, Haruko; Brenner, Malcolm K

2015-08-20

Options for targeted therapy of T-cell malignancies remain scarce. Recent clinical trials demonstrated that chimeric antigen receptors (CARs) can effectively redirect T lymphocytes to eradicate lymphoid malignancies of B-cell origin. However, T-lineage neoplasms remain a more challenging task for CAR T cells due to shared expression of most targetable surface antigens between normal and malignant T cells, potentially leading to fratricide of CAR T cells or profound immunodeficiency. Here, we report that T cells transduced with a CAR targeting CD5, a common surface marker of normal and neoplastic T cells, undergo only limited fratricide and can be expanded long-term ex vivo. These CD5 CAR T cells effectively eliminate malignant T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoma lines in vitro and significantly inhibit disease progression in xenograft mouse models of T-ALL. These data support the therapeutic potential of CD5 CAR in patients with T-cell neoplasms. © 2015 by The American Society of Hematology.

HIV Envelope gp120 Alters T Cell Receptor Mobilization in the Immunological Synapse of Uninfected CD4 T Cells and Augments T Cell Activation

PubMed Central

Deng, Jing; Mitsuki, Yu-ya; Shen, Guomiao; Ray, Jocelyn C.; Cicala, Claudia; Arthos, James; Dustin, Michael L.

2016-01-01

ABSTRACT HIV is transmitted most efficiently from cell to cell, and productive infection occurs mainly in activated CD4 T cells. It is postulated that HIV exploits immunological synapses formed between CD4 T cells and antigen-presenting cells to facilitate the targeting and infection of activated CD4 T cells. This study sought to evaluate how the presence of the HIV envelope (Env) in the CD4 T cell immunological synapse affects synapse formation and intracellular signaling to impact the downstream T cell activation events. CD4 T cells were applied to supported lipid bilayers that were reconstituted with HIV Env gp120, anti-T cell receptor (anti-TCR) monoclonal antibody, and ICAM-1 to represent the surface of HIV Env-bearing antigen-presenting cells. The results showed that the HIV Env did not disrupt immunological synapse formation. Instead, the HIV Env accumulated with TCR at the center of the synapse, altered the kinetics of TCR recruitment to the synapse and affected synapse morphology over time. The HIV Env also prolonged Lck phosphorylation at the synapse and enhanced TCR-induced CD69 upregulation, interleukin-2 secretion, and proliferation to promote virus infection. These results suggest that HIV uses the immunological synapse as a conduit not only for selective virus transmission to activated CD4 T cells but also for boosting the T cell activation state, thereby increasing its likelihood of undergoing productive replication in targeted CD4 T cells. IMPORTANCE There are about two million new HIV infections every year. A better understanding of how HIV is transmitted to susceptible cells is critical to devise effective strategies to prevent HIV infection. Activated CD4 T cells are preferentially infected by HIV, although how this is accomplished is not fully understood. This study examined whether HIV co-opts the normal T cell activation process through the so-called immunological synapse. We found that the HIV envelope is recruited to the center of the

NKL homeobox gene activities in hematopoietic stem cells, T-cell development and T-cell leukemia.

PubMed

Nagel, Stefan; Pommerenke, Claudia; Scherr, Michaela; Meyer, Corinna; Kaufmann, Maren; Battmer, Karin; MacLeod, Roderick A F; Drexler, Hans G

2017-01-01

T-cell acute lymphoblastic leukemia (T-ALL) cells represent developmentally arrested T-cell progenitors, subsets of which aberrantly express homeobox genes of the NKL subclass, including TLX1, TLX3, NKX2-1, NKX2-5, NKX3-1 and MSX1. Here, we analyzed the transcriptional landscape of all 48 members of the NKL homeobox gene subclass in CD34+ hematopoietic stem and progenitor cells (HSPCs) and during lymphopoiesis, identifying activities of nine particular genes. Four of these were expressed in HSPCs (HHEX, HLX1, NKX2-3 and NKX3-1) and three in common lymphoid progenitors (HHEX, HLX1 and MSX1). Interestingly, our data indicated downregulation of NKL homeobox gene transcripts in late progenitors and mature T-cells, a phenomenon which might explain the oncogenic impact of this group of genes in T-ALL. Using MSX1-expressing T-ALL cell lines as models, we showed that HHEX activates while HLX1, NKX2-3 and NKX3-1 repress MSX1 transcription, demonstrating the mutual regulation and differential activities of these homeobox genes. Analysis of a public T-ALL expression profiling data set comprising 117 patient samples identified 20 aberrantly activated members of the NKL subclass, extending the number of known NKL homeobox oncogene candidates. While 7/20 genes were also active during hematopoiesis, the remaining 13 showed ectopic expression. Finally, comparative analyses of T-ALL patient and cell line profiling data of NKL-positive and NKL-negative samples indicated absence of shared target genes but instead highlighted deregulation of apoptosis as common oncogenic effect. Taken together, we present a comprehensive survey of NKL homeobox genes in early hematopoiesis, T-cell development and T-ALL, showing that these genes generate an NKL-code for the diverse stages of lymphoid development which might be fundamental for regular differentiation.

NKL homeobox gene activities in hematopoietic stem cells, T-cell development and T-cell leukemia

PubMed Central

Pommerenke, Claudia; Scherr, Michaela; Meyer, Corinna; Kaufmann, Maren; Battmer, Karin; MacLeod, Roderick A. F.; Drexler, Hans G.

2017-01-01

T-cell acute lymphoblastic leukemia (T-ALL) cells represent developmentally arrested T-cell progenitors, subsets of which aberrantly express homeobox genes of the NKL subclass, including TLX1, TLX3, NKX2-1, NKX2-5, NKX3-1 and MSX1. Here, we analyzed the transcriptional landscape of all 48 members of the NKL homeobox gene subclass in CD34+ hematopoietic stem and progenitor cells (HSPCs) and during lymphopoiesis, identifying activities of nine particular genes. Four of these were expressed in HSPCs (HHEX, HLX1, NKX2-3 and NKX3-1) and three in common lymphoid progenitors (HHEX, HLX1 and MSX1). Interestingly, our data indicated downregulation of NKL homeobox gene transcripts in late progenitors and mature T-cells, a phenomenon which might explain the oncogenic impact of this group of genes in T-ALL. Using MSX1-expressing T-ALL cell lines as models, we showed that HHEX activates while HLX1, NKX2-3 and NKX3-1 repress MSX1 transcription, demonstrating the mutual regulation and differential activities of these homeobox genes. Analysis of a public T-ALL expression profiling data set comprising 117 patient samples identified 20 aberrantly activated members of the NKL subclass, extending the number of known NKL homeobox oncogene candidates. While 7/20 genes were also active during hematopoiesis, the remaining 13 showed ectopic expression. Finally, comparative analyses of T-ALL patient and cell line profiling data of NKL-positive and NKL-negative samples indicated absence of shared target genes but instead highlighted deregulation of apoptosis as common oncogenic effect. Taken together, we present a comprehensive survey of NKL homeobox genes in early hematopoiesis, T-cell development and T-ALL, showing that these genes generate an NKL-code for the diverse stages of lymphoid development which might be fundamental for regular differentiation. PMID:28151996

CXCR5-Dependent Entry of CD8 T Cells into Rhesus Macaque B-Cell Follicles Achieved through T-Cell Engineering.

PubMed

Ayala, Victor I; Deleage, Claire; Trivett, Matthew T; Jain, Sumiti; Coren, Lori V; Breed, Matthew W; Kramer, Joshua A; Thomas, James A; Estes, Jacob D; Lifson, Jeffrey D; Ott, David E

2017-06-01

Follicular helper CD4 T cells, T FH , residing in B-cell follicles within secondary lymphoid tissues, are readily infected by AIDS viruses and are a major source of persistent virus despite relative control of viral replication. This persistence is due at least in part to a relative exclusion of effective antiviral CD8 T cells from B-cell follicles. To determine whether CD8 T cells could be engineered to enter B-cell follicles, we genetically modified unselected CD8 T cells to express CXC chemokine receptor 5 (CXCR5), the chemokine receptor implicated in cellular entry into B-cell follicles. Engineered CD8 T cells expressing human CXCR5 (CD8 hCXCR5 ) exhibited ligand-specific signaling and chemotaxis in vitro Six infected rhesus macaques were infused with differentially fluorescent dye-labeled autologous CD8 hCXCR5 and untransduced CD8 T cells and necropsied 48 h later. Flow cytometry of both spleen and lymph node samples revealed higher frequencies of CD8 hCXCR5 than untransduced cells, consistent with preferential trafficking to B-cell follicle-containing tissues. Confocal fluorescence microscopy of thin-sectioned lymphoid tissues demonstrated strong preferential localization of CD8 hCXCR5 T cells within B-cell follicles with only rare cells in extrafollicular locations. CD8 hCXCR5 T cells were present throughout the follicles with some observed near infected T FH In contrast, untransduced CD8 T cells were found in the extrafollicular T-cell zone. Our ability to direct localization of unselected CD8 T cells into B-cell follicles using CXCR5 expression provides a strategy to place highly effective virus-specific CD8 T cells into these AIDS virus sanctuaries and potentially suppress residual viral replication. IMPORTANCE AIDS virus persistence in individuals under effective drug therapy or those who spontaneously control viremia remains an obstacle to definitive treatment. Infected follicular helper CD4 T cells, T FH , present inside B-cell follicles represent a

Supernatural T cells: genetic modification of T cells for cancer therapy.

PubMed

Kershaw, Michael H; Teng, Michele W L; Smyth, Mark J; Darcy, Phillip K

2005-12-01

Immunotherapy is receiving much attention as a means of treating cancer, but complete, durable responses remain rare for most malignancies. The natural immune system seems to have limitations and deficiencies that might affect its ability to control malignant disease. An alternative to relying on endogenous components in the immune repertoire is to generate lymphocytes with abilities that are greater than those of natural T cells, through genetic modification to produce 'supernatural' T cells. This Review describes how such T cells can circumvent many of the barriers that are inherent in the tumour microenvironment while optimizing T-cell specificity, activation, homing and antitumour function.

[gammadelta T cells stimulated by zoledronate kill osteosarcoma cells].

PubMed

Jiang, Hui; Xu, Qiang; Yang, Chao; Cao, Zhen-Guo; Li, Zhao-Xu; Ye, Zhao-Ming

2010-12-01

To investigate the cytotoxicity of human γδT cells from PBMCs stimulated by zoledronate against osteosarcoma cell line HOS in vitro and in vivo and evaluate the relavent pathways. The peripheral blood mononuclear cells (PBMCs)of healthy donors were stimulated by single dose zoledronate and cultured in the present of IL-2 for two weeks, analysising the percentage of γδT cells on a FACSCalibur cytometer.Study the cytotoxicity of γδT cells against the osteosarcoma line HOS using LDH release assay kit. Pre-treatment of γδT cells with anti-human γδTCR antibody, anti-human NKG2D antibody and concanamycin A to bolck the relavent pathways for evaluating the mechenisms of its cytotoxicity. In vivo, BALB/c mice were inoculated subcutaneously osteosarcoma cell HOS for developing hypodermal tumors. And they were randomized into two groups: unteated group, γδT cell therapy group. Tumor volume and weight of the two groups were compared. After two weeks of culture, γδT cells from zoledronate-stimulated PBMCs could reach (95±3)%. When the E:T as 6:1, 12:1, 25:1, 50:1, the percentage of osteosarcoma cell HOS killed by γδT cells was 26.8%, 31.5%, 37.8%, 40.9%, respectively.When anti-huma γδTCR antibody, anti-human NKG2D antibody and concanamycin A blocked the relavent pathways, the percentage was 32.3%, 4.7%, 16.7% ( E:T as 25:1), respectively. In vivo, the tumor inhibition rate of the group of γδT cell therapy was 42.78%. γδT cells derived from PBMCs stimulated by zoledronate can acquired pure γδT cells. And they show strong cytoxicity against osteosarcoma cell line HOS in vitro and in vivo.

Intracellular cysteine oxidation is modulated by aquaporin-8-mediated hydrogen peroxide channeling in leukaemia cells.

PubMed

Vieceli Dalla Sega, Francesco; Prata, Cecilia; Zambonin, Laura; Angeloni, Cristina; Rizzo, Benedetta; Hrelia, Silvana; Fiorentini, Diana

2017-03-01

The modulation of H 2 O 2 production by NADPH oxidase (Nox), on vascular endothelial growth factor (VEGF) stimulation, affects the redox signaling linked to cancer cell proliferation. H 2 O 2 signal transduction involves reversible oxidation of thiol proteins, leading to the formation of cysteine sulfenic acids, responsible for the temporary inactivation of many phosphatases. These events imply that H 2 O 2 reaches its intracellular targets. As Aquaporin-8 (AQP8) has been demonstrated to funnel Nox-produced H 2 O 2 across the plasma membrane, this study aims to elucidate the role of AQP8 in the redox signaling occurring in human leukaemia B1647 cells that constitutively produce VEGF. AQP8 overexpression or silencing resulted in the modulation of VEGF ability of increasing or decreasing, respectively, H 2 O 2 intracellular level. Moreover, data obtained by a dimedone-based immunochemical method for sulfenic acid detection demonstrate that the expression of AQP8 can modulate the amplitude of downstream events, altering the activity of redox-sensitive targets. In particular, AQP8 affected VEGF-induced redox signaling by increasing the sulfenation of the tumor suppressor PTEN, which resulted in its inactivation and, in turn, caused Akt activation. Therefore, the dimedone-based method for easily monitoring cellular protein sulfenation allowed to demonstrate, for the first time, the role of AQP8 on the fine tune of cysteine oxidation in target proteins involved in leukaemia cell proliferation pathways. © 2016 BioFactors, 43(2):232-242, 2017. © 2016 International Union of Biochemistry and Molecular Biology.

Pathogen-Specific T Cell Polyfunctionality Is a Correlate of T Cell Efficacy and Immune Protection

PubMed Central

Boyd, Anders; Almeida, Jorge R.; Darrah, Patricia A.; Sauce, Delphine; Seder, Robert A.; Appay, Victor; Gorochov, Guy; Larsen, Martin

2015-01-01

Introduction Understanding the factors that delineate the efficacy of T cell responses towards pathogens is crucial for our ability to develop potent therapies against infectious diseases. Multidimensional evaluation of T cell functionality at the single-cell level enables exhaustive analysis of combinatorial functional properties, hence polyfunctionality. We have recently invented an algorithm that quantifies polyfunctionality, the Polyfunctionality Index (Larsen et al. PLoS One 2012). Here we demonstrate that quantitative assessment of T cell polyfunctionality correlates with T cell efficacy measured as the capacity to kill target cells in vitro and control infection in vivo. Methods We employed the polyfunctionality index on two datasets selected for their unique ability to evaluate the polyfunctional imprint on T cell efficacy. 1) HIV-specific CD8+ T cells and 2) Leishmania major-specific CD4+ T cells were analysed for their capacity to secrete multiple effector molecules, kill target cells and control infection. Briefly, employing the Polyfunctionality Index algorithm we determined the parameter estimates resulting in optimal correlation between T cell polyfunctionality and T cell efficacy. Results T cell polyfunctionality is correlated with T cell efficacy measured as 1) target killing (r=0.807, P<0.0001) and 2) lesion size upon challenge with Leishmania major (r=-0.50, P=0.004). Contrary to an approach relying on the Polyfunctionality Index algorithm, quantitative evaluation of T cell polyfunctionality traditionally ignores the gradual contribution of more or less polyfunctional T cells. Indeed, comparing both approaches we show that optimal description of T cell efficacy is obtained when gradually integrating all levels of polyfunctionality in accordance with the Polyfunctionality Index. Conclusions Our study presents a generalizable methodology to objectively evaluate the impact of polyfunctionality on T cell efficacy. We show that T cell polyfunctionality

Identification of novel gammadelta T-cell subsets following bacterial infection in the absence of Vgamma1+ T cells: homeostatic control of gammadelta T-cell responses to pathogen infection by Vgamma1+ T cells.

PubMed

Newton, Darren J; Andrew, Elizabeth M; Dalton, Jane E; Mears, Rainy; Carding, Simon R

2006-02-01

Although gammadelta T cells are a common feature of many pathogen-induced immune responses, the factors that influence, promote, or regulate the response of individual gammadelta T-cell subsets to infection is unknown. Here we show that in the absence of Vgamma1+ T cells, novel subsets of gammadelta T cells, expressing T-cell receptor (TCR)-Vgamma chains that normally define TCRgammadelta+ dendritic epidermal T cells (DETCs) (Vgamma5+), intestinal intraepithelial lymphocytes (iIELs) (Vgamma7+), and lymphocytes associated with the vaginal epithelia (Vgamma6+), are recruited to the spleen in response to bacterial infection in TCR-Vgamma1-/- mice. By comparison of phenotype and structure of TCR-Vgamma chains and/or -Vdelta chains expressed by these novel subsets with those of their epithelium-associated counterparts, the Vgamma6+ T cells elicited in infected Vgamma1-/- mice were shown to be identical to those found in the reproductive tract, from where they are presumably recruited in the absence of Vgamma1+ T cells. By contrast, Vgamma5+ and Vgamma7+ T cells found in infected Vgamma1-/- mice were distinct from Vgamma5+ DETCs and Vgamma7+ iIELs. Functional analyses of the novel gammadelta T-cell subsets identified for infected Vgamma1-/- mice showed that whereas the Vgamma5+ and Vgamma7+ subsets may compensate for the absence of Vgamma1+ T cells by producing similar cytokines, they do not possess cytocidal activity and they cannot replace the macrophage homeostasis function of Vgamma1+ T cells. Collectively, these findings identify novel subsets of gammadelta T cells, the recruitment and activity of which is under the control of Vgamma1+ T cells.

Loss of RUNX1/AML1 arginine-methylation impairs in peripheral T cell homeostasis

PubMed Central

Mizutani, Shinsuke; Yoshida, Tatsushi; Zhao, Xinyang; Nimer, Stephen D.; Taniwaki, Masafumi; Okuda, Tsukasa

2016-01-01

Summary RUNX1 (previously termed AML1) is a frequent target of human leukaemia-associated gene aberrations, and it encodes the DNA-binding subunit of the Core-Binding Factor transcription factor complex. RUNX1 expression is essential for the initiation of definitive haematopoiesis, for steady-state thrombopoiesis, and for normal lymphocytes development. Recent studies revealed that protein arginine methyltransferase 1 (PRMT1), which accounts for the majority of the type I PRMT activity in cells, methylates two arginine residues in RUNX1 (R206 and R210), and these modifications inhibit corepressor-binding to RUNX1 thereby enhancing its transcriptional activity. In order to elucidate the biological significance of these methylations, we established novel knock-in mouse lines with non-methylable, double arginine-to-lysine (RTAMR-to-KTAMK) mutations in RUNX1. Homozygous Runx1KTAMK/KTAMK mice are born alive and appear normal during adulthood. However, Runx1KTAMK/KTAMK mice showed a reduction in CD3+ T lymphoid cells and a decrease in CD4+ T cells in peripheral lymphoid organs, in comparison to their wild-type littermates, leading to a reduction in the CD4+ to CD8+ T-cell ratio. These findings suggest that arginine-methylation of RUNX1 in the RTAMR-motif is dispensable for the development of definitive haematopoiesis and for steady-state platelet production, however this modification affects the role of RUNX1 in the maintenance of the peripheral CD4+ T-cell population. PMID:26010396

Single-Cell RNA Sequencing of Human T Cells.

PubMed

Villani, Alexandra-Chloé; Shekhar, Karthik

2017-01-01

Understanding how populations of human T cells leverage cellular heterogeneity, plasticity, and diversity to achieve a wide range of functional flexibility, particularly during dynamic processes such as development, differentiation, and antigenic response, is a core challenge that is well suited for single-cell analysis. Hypothesis-free evaluation of cellular states and subpopulations by transcriptional profiling of single T cells can identify relationships that may be obscured by targeted approaches such as FACS sorting on cell-surface antigens, or bulk expression analysis. While this approach is relevant to all cell types, it is of particular interest in the study of T cells for which classical phenotypic criteria are now viewed as insufficient for distinguishing different T cell subtypes and transitional states, and defining the changes associated with dysfunctional T cell states in autoimmunity and tumor-related exhaustion. This unit describes a protocol to generate single-cell transcriptomic libraries of human blood CD4 + and CD8 + T cells, and also introduces the basic bioinformatic steps to process the resulting sequence data for further computational analysis. We show how cellular subpopulations can be identified from transcriptional data, and derive characteristic gene expression signatures that distinguish these states. We believe single-cell RNA-seq is a powerful technique to study the cellular heterogeneity in complex tissues, a paradigm that will be of great value for the immune system.

Septin9 is involved in T-cell development and CD8+ T-cell homeostasis.

PubMed

Lassen, Louise Berkhoudt; Füchtbauer, Annette; Schmitz, Alexander; Sørensen, Annette Balle; Pedersen, Finn Skou; Füchtbauer, Ernst-Martin

2013-06-01

SEPTIN9 (SEPT9) is a filament-forming protein involved in numerous cellular processes. We have used a conditional knock out allele of Sept9 to specifically delete Sept9 in T-cells. As shown by fluorescence-activated cell sorting, loss of Sept9 at an early thymocyte stage in the thymus results in increased numbers of double-negative cells indicating that SEPT9 is involved in the transition from the double-negative stage during T-cell development. Accordingly, the relative numbers of mature T-cells in the periphery are decreased in mice with a T-cell-specific deletion of Sept9. Proliferation of Sept9-deleted CD8(+) T-cells from the spleen is decreased upon stimulation in culture. The altered T-cell homeostasis caused by the loss of Sept9 results in an increase of CD8(+) central memory T-cells.

Adoptive T-cell therapy for cancer: The era of engineered T cells.

PubMed

Bonini, Chiara; Mondino, Anna

2015-09-01

Tumors originate from a number of genetic events that deregulate homeostatic mechanisms controlling normal cell behavior. The immune system, devoted to patrol the organism against pathogenic events, can identify transformed cells, and in several cases cause their elimination. It is however clear that several mechanisms encompassing both central and peripheral tolerance limit antitumor immunity, often resulting into progressive diseases. Adoptive T-cell therapy with either allogeneic or autologous T cells can transfer therapeutic immunity. To date, genetic engineering of T cells appears to be a powerful tool for shaping tumor immunity. In this review, we discuss the most recent achievements in the areas of suicide gene therapy, and TCR-modified T cells and chimeric antigen receptor gene-modified T cells. We provide an overview of current strategies aimed at improving the safety and efficacy of these approaches, with an outlook on prospective developments. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Human germinal center CD4+CD57+ T cells act differently on B cells than do classical T-helper cells.

PubMed

Bouzahzah, F; Bosseloir, A; Heinen, E; Simar, L J

1995-01-01

We have isolated two subtypes of helper T cells from human tonsils: CD4+CD57+ cells, mostly located in the germinal center (GC), and CD4+CD57- cells, distributed through the interfollicular areas but also present in the GC. In a functional study, we have compared the capacities of these T-cell subtypes to stimulate B cells in cocultures. In order to block T-cell proliferation while maintaining their activation level, we pretreated isolated T cells with mitomycin C prior to culture in the presence of B cells and added polyclonal activators such as PHA and Con A, combined or not with IL-2. Contrary to CD4+ CD57- cells, CD4+CD57+ cells did not markedly enhance B-cell proliferation. Even when sIgD.B cells typical of germinal center cells were tested, the CD4+CD57+ cells had no significant effect. This is in accordance with the location of these cells: They mainly occupy the light zones of the GC where few B cells divide. Even when added to preactivated, actively proliferating cells, CD4+CD57 cells failed to modulate B-cell multiplication. On the supernatants of B-cell-T-cell cocultures, we examined by the ELISA technique the effect of T cells on Ig synthesis. Contrary to CD57+ T cells, whose effect was strong, CD57- T cells weakly stimulated Ig synthesis. More IgM than IgG was generally found. Because CD57 antigen is a typical marker of natural killer cells, we tested the cytolytic activity of tonsillar CD4+CD57+ cells on K562 target cells. Unlike NK cells, neither CD4+CD57+ nor CD4+CD57- cells exhibit any cytotoxicity. Thus, germinal center CD4+CD57+ cells are not cytolytic and do not strongly stimulate either B-cell proliferation or Ig secretion. CD4+CD57- cells, however, enhance B-cell proliferation and differentiation, thus acting like the classical helper cells of the T-dependent areas.

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

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.

Correlation between thyroidal and peripheral blood total T cells, CD8+ T cells, and CD8+ T- regulatory cells and T-cell reactivity to calsequestrin and collagen XIII in patients with Graves' ophthalmopathy.

PubMed

Al-Ansari, Farah; Lahooti, Hooshang; Stokes, Leanne; Edirimanne, Senarath; Wall, Jack

2018-05-22

Purpose/aim of the study: Graves' ophthalmopathy (GO) is closely related to the thyroid autoimmune disorder Graves' disease. Previous studies have suggested roles for thyroidal CD8 +  T cells and autoimmunity against calsequestrin-1 (CASQ)-1 in the link between thyroidal and orbital autoimmune reactions in GO. A role for autoimmunity against CollXIII has also been suggested. In this study, we aimed to investigate correlations between some thyroidal and peripheral blood T-cell subsets and thyroidal T-cell reactivity against CASQ1 and CollXIII in patients with GO. Fresh thyroid tissues were processed by enzyme digestion and density gradient to isolate mononuclear cells (MNCs). Peripheral blood MNCs were also isolated using density gradient. Flow-cytometric analysis was used to identify the various T-cell subsets. T -cell reactivity to CASQ1 and CollXIII was measured by a 5-day culture of the MNCs and BrdU uptake method. We found a positive correlation between thyroidal CD8 +  T cells and CD8 +  T-regulatory (T-reg) cells in patients with GO. Thyroidal T cells from two out of the three patients with GO tested (66.7%) showed a positive response to CASQ1, while thyroidal T cells from none of the six Graves' Disease patients without ophthalmopathy (GD) tested showed a positive response to this antigen. Thyroidal T cells from these patient groups however, showed no significant differences in their response to CollXIII. Our observations provide further evidence for a possible role of thyroidal CD8 +  T cells, CD8 +  T-reg cells and the autoantigen CASQ1 in the link between thyroidal and orbital autoimmune reactions of GO.

Increase of endothelial progenitor cells in acute graft-versus-host disease after allogeneic haematopoietic stem cell transplantation for acute myeloid leukaemia.

PubMed

Medinger, Michael; Heim, Dominik; Gerull, Sabine; Halter, Jörg; Krenger, Werner; Buser, Andreas; Lengerke, Claudia; Bucher, Christoph; Passweg, Jakob

2016-08-01

Circulating endothelial progenitor cells (EPCs; CD31+ CD34(bright)CD133+ CD45(dim) cells) are novel markers of endothelial dysfunction and related to inflammatory processes such as acute graft-versus-host disease (aGvHD). 47 patients with acute myeloid leukaemia (AML) who were in complete remission as they underwent allogeneic hematopoietic stem cell transplantation with myeloablative conditioning with PBSC as stem cell source were enrolled in the study. Blood samples for the quantitative analysis of circulating EPC levels were drawn at different time points in patients with and without aGvHD. CD34+ VEGFR2/KDR+ CD133+ triple-positive cells identified among CD34+ cells by FACS. EPC were quantified and data are presented as cells/ml whole blood. Circulating EPC levels were not significantly different in patients with and without aGvHD prior to conditioning (baseline) and at the time of engraftment. However, at diagnosis of aGvHD≥grade 2, EPC levels increased whereas in patients without aGvHD the EPC levels remained significantly lower (3021±278 versus 2322±195 cells/ml; p<0.001). Patients with steroid-refractory aGvHD had high levels of EPC throughout. EPC levels fell in responding patients. Our results demonstrate that the number of circulating EPCs is increased in patients with aGvHD compared to patients without aGvHD. Copyright © 2016 Elsevier Ltd. All rights reserved.

The cytotoxic action of the CD56+ fraction of cytokine-induced killer cells against a K562 cell line is mainly restricted to the natural killer cell subset.

PubMed

Chieregato, Katia; Zanon, Cristina; Castegnaro, Silvia; Bernardi, Martina; Amati, Eliana; Sella, Sabrina; Rodeghiero, Francesco; Astori, Giuseppe

2017-01-01

Cytokine-induced killer cells are polyclonal T cells generated ex vivo and comprise two main subsets: the CD56- fraction, possessing an alloreactive potential caused by T cells (CD3+CD56-), and the CD56+ fraction, characterised by a strong antitumour capacity induced by natural killer-like T cells (NK-like T, CD3+CD56+) and natural killer cells (NK, CD3-CD56+ bright). We investigated the cytotoxic action of selected CD56+ cell subpopulations against a human chronic myeloid leukaemia (K562) cell line. After immunomagnetic selection of the CD56+ cell fraction, NK bright cells (CD3-CD56+ bright) and two subsets of NK-like T cells (CD3+CD56+), called NK-like T CD56 dim and NK-like T CD56 bright, could be identified. The cytotoxic effect against K562 cells was mainly exerted by the NK bright subpopulation and resulted to be inversely correlated with the percentage of NK-like T CD56 dim cells in the culture. The lytic action appeared to be independent of cell degranulation as suggested by the lack of change in the expression of CD107a. We conclude that the cytotoxic action of CD56+ cells against a K562 cell line is mainly due to the NK cells.

A stromal cell free culture system generates mouse pro-T cells that can reconstitute T-cell compartments in vivo.

PubMed

Gehre, Nadine; Nusser, Anja; von Muenchow, Lilly; Tussiwand, Roxane; Engdahl, Corinne; Capoferri, Giuseppina; Bosco, Nabil; Ceredig, Rhodri; Rolink, Antonius G

2015-03-01

T-cell lymphopenia following BM transplantation or diseases such as AIDS result in immunodeficiency. Novel approaches to ameliorate this situation are urgently required. Herein, we describe a novel stromal cell free culture system in which Lineage(-) Sca1(+)c-kit(+) BM hematopoietic progenitors very efficiently differentiate into pro-T cells. This culture system consists of plate-bound Delta-like 4 Notch ligand and the cytokines SCF and IL-7. The pro-T cells developing in these cultures express CD25, CD117, and partially CD44; express cytoplasmic CD3ε; and have their TCRβ locus partially D-J rearranged. They could be expanded for over 3 months and used to reconstitute the T-cell compartments of sublethally irradiated T-cell-deficient CD3ε(-/-) mice or lethally irradiated WT mice. Pro-T cells generated in this system could partially correct the T-cell lymphopenia of pre-Tα(-/-) mice. However, reconstituted CD3ε(-/-) mice suffered from a wasting disease that was prevented by co-injection of purified CD4(+) CD25(high) WT Treg cells. In a T-cell-sufficient or T-lymphopenic setting, the development of disease was not observed. Thus, this in vitro culture system represents a powerful tool to generate large numbers of pro-T cells for transplantation and possibly with clinical applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Detecting T-cell reactivity to whole cell vaccines

PubMed Central

Brusic, Ana; Hainz, Ursula; Wadleigh, Martha; Neuberg, Donna; Su, Mei; Canning, Christine M.; DeAngelo, Daniel J.; Stone, Richard M.; Lee, Jeng-Shin; Mulligan, Richard C.; Ritz, Jerome; Dranoff, Glenn; Sasada, Tetsuro; Wu, Catherine J.

2012-01-01

BCR-ABL+ K562 cells hold clinical promise as a component of cancer vaccines, either as bystander cells genetically modified to express immunostimulatory molecules, or as a source of leukemia antigens. To develop a method for detecting T-cell reactivity against K562 cell-derived antigens in patients, we exploited the dendritic cell (DC)-mediated cross-presentation of proteins generated from apoptotic cells. We used UVB irradiation to consistently induce apoptosis of K562 cells, which were then fed to autologous DCs. These DCs were used to both stimulate and detect antigen-specific CD8+ T-cell reactivity. As proof-of-concept, we used cross-presented apoptotic influenza matrix protein-expressing K562 cells to elicit reactivity from matrix protein-reactive T cells. Likewise, we used this assay to detect increased anti-CML antigen T-cell reactivity in CML patients that attained long-lasting clinical remissions following immunotherapy (donor lymphocyte infusion), as well as in 2 of 3 CML patients vaccinated with lethally irradiated K562 cells that were modified to secrete high levels of granulocyte macrophage colony-stimulating factor (GM-CSF). This methodology can be readily adapted to examine the effects of other whole tumor cell-based vaccines, a scenario in which the precise tumor antigens that stimulate immune responses are unknown. PMID:23170257

MS4a4B, a CD20 homologue in T cells, inhibits T cell propagation by modulation of cell cycle.

PubMed

Xu, Hui; Yan, Yaping; Williams, Mark S; Carey, Gregory B; Yang, Jingxian; Li, Hongmei; Zhang, Guang-Xian; Rostami, Abdolmohamad

2010-11-01

MS4a4B, a CD20 homologue in T cells, is a novel member of the MS4A gene family in mice. The MS4A family includes CD20, FcεRIβ, HTm4 and at least 26 novel members that are characterized by their structural features: with four membrane-spanning domains, two extracellular domains and two cytoplasmic regions. CD20, FcεRIβ and HTm4 have been found to function in B cells, mast cells and hematopoietic cells respectively. However, little is known about the function of MS4a4B in T cell regulation. We demonstrate here that MS4a4B negatively regulates mouse T cell proliferation. MS4a4B is highly expressed in primary T cells, natural killer cells (NK) and some T cell lines. But its expression in all malignant T cells, including thymoma and T hybridoma tested, was silenced. Interestingly, its expression was regulated during T cell activation. Viral vector-driven overexpression of MS4a4B in primary T cells and EL4 thymoma cells reduced cell proliferation. In contrast, knockdown of MS4a4B accelerated T cell proliferation. Cell cycle analysis showed that MS4a4B regulated T cell proliferation by inhibiting entry of the cells into S-G2/M phase. MS4a4B-mediated inhibition of cell cycle was correlated with upregulation of Cdk inhibitory proteins and decreased levels of Cdk2 activity, subsequently leading to inhibition of cell cycle progression. Our data indicate that MS4a4B negatively regulates T cell proliferation. MS4a4B, therefore, may serve as a modulator in the negative-feedback regulatory loop of activated T cells.

Antigen-Specific T-Cell Activation Independently of the MHC: Chimeric Antigen Receptor-Redirected T Cells

PubMed Central

Chmielewski, Markus; Hombach, Andreas A.; Abken, Hinrich

2013-01-01

Adoptive T-cell therapy has recently shown promise in initiating a lasting anti-tumor response with spectacular therapeutic success in some cases. Specific T-cell therapy, however, is limited since a number of cancer cells are not recognized by T cells due to various mechanisms including the limited availability of tumor-specific T cells and deficiencies in antigen processing or major histocompatibility complex (MHC) expression of cancer cells. To make adoptive cell therapy applicable for the broad variety of cancer entities, patient’s T cells are engineered ex vivo with pre-defined specificity by a recombinant chimeric antigen receptor (CAR) which consists in the extracellular part of an antibody-derived domain for binding with a “tumor-associated antigen” and in the intracellular part of a T-cell receptor (TCR)-derived signaling moiety for T-cell activation. The specificity of CAR-mediated T-cell recognition is defined by the antibody domain, is independent of MHC presentation and can be extended to any target for which an antibody is available. We discuss the advantages and limitations of MHC-independent T-cell targeting by an engineered CAR in comparison to TCR modified T cells and the impact of the CAR activation threshold on redirected T-cell activation. Finally we review most significant progress recently made in early stage clinical trials to treat cancer. PMID:24273543

Antigen-Specific T-Cell Activation Independently of the MHC: Chimeric Antigen Receptor-Redirected T Cells.

PubMed

Chmielewski, Markus; Hombach, Andreas A; Abken, Hinrich

2013-01-01

Adoptive T-cell therapy has recently shown promise in initiating a lasting anti-tumor response with spectacular therapeutic success in some cases. Specific T-cell therapy, however, is limited since a number of cancer cells are not recognized by T cells due to various mechanisms including the limited availability of tumor-specific T cells and deficiencies in antigen processing or major histocompatibility complex (MHC) expression of cancer cells. To make adoptive cell therapy applicable for the broad variety of cancer entities, patient's T cells are engineered ex vivo with pre-defined specificity by a recombinant chimeric antigen receptor (CAR) which consists in the extracellular part of an antibody-derived domain for binding with a "tumor-associated antigen" and in the intracellular part of a T-cell receptor (TCR)-derived signaling moiety for T-cell activation. The specificity of CAR-mediated T-cell recognition is defined by the antibody domain, is independent of MHC presentation and can be extended to any target for which an antibody is available. We discuss the advantages and limitations of MHC-independent T-cell targeting by an engineered CAR in comparison to TCR modified T cells and the impact of the CAR activation threshold on redirected T-cell activation. Finally we review most significant progress recently made in early stage clinical trials to treat cancer.

γ/δ T cell subsets in human aging using the classical α/β T cell model.

PubMed

Vasudev, Anusha; Ying, Crystal Tan Tze; Ayyadhury, Shamini; Puan, Kia Joo; Andiappan, Anand Kumar; Nyunt, Ma Shwe Zin; Shadan, Nurhidaya Binte; Mustafa, Seri; Low, Ivy; Rotzschke, Olaf; Fulop, Tamas; Ng, Tze Pin; Larbi, Anis

2014-10-01

Aging is associated with an increased susceptibility to infections and diseases. It has also been associated with reduced functionality and altered distribution of immune cells, especially T cells. Whereas classical α/β T cells, especially CD8(+) T cells, were shown to be highly susceptible to aging, the effects of viral persistent stimulations on the fate of γ/δ T cells are much less documented. Healthy, elderly individuals of Chinese ethnical background were recruited under the aegis of SLAS-II. In this observational study, γ/δ T cell populations were characterized by flow cytometry and compared with the α/β CD4(+) and CD8(+) T cells in elderly and young controls. In our study, we identified a reduced frequency of γ/δ T cells but not α/β T cells with aging. The classical markers of α/β T cell aging, including CD28, CD27, and CD57, did not prove significant for γ/δ T cells. The extreme range of expression of these markers in γ/δ T cells was responsible for the lack of relationship between γ/δ T cell subsets, CD4/CD8 ratio, and anti-CMV titers that was significant for α/β T cells and, especially, CD8(+) T cells. Although markers of aging for γ/δ T cells are not clearly identified, our data collectively suggest that the presence of CD27 γ/δ T cells is associated with markers of α/β T cell aging. © 2014 Society for Leukocyte Biology.

Redirecting T cells to eradicate B-cell acute lymphoblastic leukemia: bispecific T-cell engagers and chimeric antigen receptors.

PubMed

Aldoss, I; Bargou, R C; Nagorsen, D; Friberg, G R; Baeuerle, P A; Forman, S J

2017-04-01

Recent advances in antibody technology to harness T cells for cancer immunotherapy, particularly in the difficult-to-treat setting of relapsed/refractory acute lymphoblastic leukemia (r/r ALL), have led to innovative methods for directing cytotoxic T cells to specific surface antigens on cancer cells. One approach involves administration of soluble bispecific (or dual-affinity) antibody-based constructs that temporarily bridge T cells and cancer cells. Another approach infuses ex vivo-engineered T cells that express a surface plasma membrane-inserted antibody construct called a chimeric antigen receptor (CAR). Both bispecific antibodies and CARs circumvent natural target cell recognition by creating a physical connection between cytotoxic T cells and target cancer cells to activate a cytolysis signaling pathway; this connection allows essentially all cytotoxic T cells in a patient to be engaged because typical tumor cell resistance mechanisms (such as T-cell receptor specificity, antigen processing and presentation, and major histocompatibility complex context) are bypassed. Both the bispecific T-cell engager (BiTE) antibody construct blinatumomab and CD19-CARs are immunotherapies that have yielded encouraging remission rates in CD19-positive r/r ALL, suggesting that they might serve as definitive treatments or bridging therapies to allogeneic hematopoietic cell transplantation. With the introduction of these immunotherapies, new challenges arise related to unique toxicities and distinctive pathways of resistance. An increasing body of knowledge is being accumulated on how to predict, prevent, and manage such toxicities, which will help to better stratify patient risk and tailor treatments to minimize severe adverse events. A deeper understanding of the precise mechanisms of action and immune resistance, interaction with other novel agents in potential combinations, and optimization in the manufacturing process will help to advance immunotherapy outcomes in the r

Seroprevalence of human T cell leukaemia/lymphoma virus type I (HTLV-I) in pregnant women, patients attending venereological outpatient services and intravenous drug users from Slovenia.

PubMed

Poljak, M; Bednarik, J; Rednak, K; Seme, K; Kristancic, L; Celan-Lucu, B

1998-01-01

To establish current seroprevalence of human T cell leukaemia/lymphoma virus type I (HTLV-I) infection in some low- and high-risk populations from Slovenia, 10,369 and 869 serum samples collected during Slovenian 1994 unlinked surveys of human immunodeficiency viruses seroprevalence in pregnant women and patients attending venereological outpatient services, respectively, and 219 serum samples collected from Slovenian intravenous drug abusers during 1995 and 1996, were screened for the presence of anti-HTLV-I antibodies using commercial particle agglutination test Serodia HTLV-I (Fujirebio, Tokyo, Japan). Only one sample obtained from a pregnant woman was found repeatedly positive in the screening test. Presence of anti-HTLV-I antibodies in the reactive sample was undoubtedly confirmed with supplemental Western blot test. The prevalence of antibodies to HTLV-I in the Slovenian population might be somewhere between one in 10,000 (0.01%) and one in 15,000 (0.0066%), which is similar or even higher to prevalence rates in other European countries.

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.

γδ T Cells Shape Preimmune Peripheral B Cell Populations.

PubMed

Huang, Yafei; Getahun, Andrew; Heiser, Ryan A; Detanico, Thiago O; Aviszus, Katja; Kirchenbaum, Greg A; Casper, Tamara L; Huang, Chunjian; Aydintug, M Kemal; Carding, Simon R; Ikuta, Koichi; Huang, Hua; Wysocki, Lawrence J; Cambier, John C; O'Brien, Rebecca L; Born, Willi K

2016-01-01

We previously reported that selective ablation of certain γδ T cell subsets, rather than removal of all γδ T cells, strongly affects serum Ab levels in nonimmunized mice. This type of manipulation also changed T cells, including residual γδ T cells, revealing some interdependence of γδ T cell populations. For example, in mice lacking Vγ4(+) and Vγ6(+) γδ T cells (B6.TCR-Vγ4(-/-)/6(-/-)), we observed expanded Vγ1(+) cells, which changed in composition and activation and produced more IL-4 upon stimulation in vitro, increased IL-4 production by αβ T cells as well as spontaneous germinal center formation in the spleen, and elevated serum Ig and autoantibodies. We therefore examined B cell populations in this and other γδ-deficient mouse strains. Whereas immature bone marrow B cells remained largely unchanged, peripheral B cells underwent several changes. Specifically, transitional and mature B cells in the spleen of B6.TCR-Vγ4(-/-)/6(-/-) mice and other peripheral B cell populations were diminished, most of all splenic marginal zone (MZ) B cells. However, relative frequencies and absolute numbers of Ab-producing cells, as well as serum levels of Abs, IL-4, and BAFF, were increased. Cell transfers confirmed that these changes are directly dependent on the altered γδ T cells in this strain and on their enhanced potential of producing IL-4. Further evidence suggests the possibility of direct interactions between γδ T cells and B cells in the splenic MZ. Taken together, these data demonstrate the capability of γδ T cells of modulating size and productivity of preimmune peripheral B cell populations. Copyright © 2015 by The American Association of Immunologists, Inc.

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.

Reprogramming T cell Lymphocytes to Induced Pluripotent Stem Cells

NASA Astrophysics Data System (ADS)

Bared, Kalia

The discovery of induced pluripotent stem cells (iPSC) provided a novel technology for the study of development and pharmacology and complement embryonic stem cells (ES) for cell therapy applications. Though iPSC are derived from adult tissue they are comparable to ES cells in their behavior; multi-lineage differentiation and self-renewal. This makes iPSC research appealing because they can be studied in great detail and expanded in culture broadly. Fibroblasts were the first cell type reprogrammed to an iPSC using a retrovirus vector, since then alternative cell types including lymphocytes have been used to generate iPSC. Different types of vectors have also been developed to enhance iPSC formation and quality. However, specific T lymphocyte subsets have not been shown to reprogram to a pluripotent state to date. Here, we proposed to derive iPSC from peripheral blood effector and central memory T cells, reasoning that the resultant iPSC will maintain the epigenetic memory of a T lymphocyte, including the T cell receptor (TCR) gene rearrangement. This epigenetic memory will enable the differentiation and expansion of T cell iPSC into professional T cells containing a specific TCR. These could then be used for cell therapy to target specific antigens, as well as to improve culture techniques to expand T cells in vitro. We studied different gene delivery methods to derive iPSC from different types of T lymphocytes. We assessed the viability of viral transduction using flow cytometry to detect green fluorescent marker contained in the viral construct and quantitative real time polymerase chain reaction (qRT-PCR) to detect Oct4, Klf4, Sox2, and c-Myc gene expression. Our results demonstrate that the Sendai virus construct is the most feasible platform to reprogram T lymphocytes. We anticipate that this platform will provide an efficient and safe approach to derive iPSC from different T cell subsets, including memory T cells.

IgV gene intraclonal diversification and clonal evolution in B-cell chronic lymphocytic leukaemia.

PubMed

Bagnara, Davide; Callea, Vincenzo; Stelitano, Caterina; Morabito, Fortunato; Fabris, Sonia; Neri, Antonino; Zanardi, Sabrina; Ghiotto, Fabio; Ciccone, Ermanno; Grossi, Carlo Enrico; Fais, Franco

2006-04-01

Intraclonal diversification of immunoglobulin (Ig) variable (V) genes was evaluated in leukaemic cells from a B-cell chronic lymphocytic leukaemia (B-CLL) case over a 2-year period at four time points. Intraclonal heterogeneity was analysed by sequencing 305 molecular clones derived from polymerase chain reaction amplification of B-CLL cell IgV heavy (H) and light (C) chain gene rearrangements. Sequences were compared with evaluating intraclonal variation and the nature of somatic mutations. Although IgV intraclonal variation was detected at all time points, its level decreased with time and a parallel emergence of two more represented V(H)DJ(H) clones was observed. They differed by nine nucleotide substitutions one of which only caused a conservative replacement aminoacid change. In addition, one V(L)J(L) rearrangement became more represented over time. Analyses of somatic mutations suggest antigen selection and impairment of negative selection of neoplastic cells. In addition, a genealogical tree representing a model of clonal evolution of the neoplastic cells was created. It is of note that, during the period of study, the patient showed clinical progression of disease. We conclude that antigen stimulation and somatic hypermutation may participate in disease progression through the selection and expansion of neoplastic subclone(s).

CD4+CD62L+ Central Memory T Cells Can Be Converted to Foxp3+ T Cells

PubMed Central

Zhang, Xiaolong; Chang Li, Xian; Xiao, Xiang; Sun, Rui; Tian, Zhigang; Wei, Haiming

2013-01-01

The peripheral Foxp3+ Treg pool consists of naturally arising Treg (nTreg) and adaptive Treg cells (iTreg). It is well known that naive CD4+ T cells can be readily converted to Foxp3+ iTreg in vitro, and memory CD4+ T cells are resistant to conversion. In this study, we investigated the induction of Foxp3+ T cells from various CD4+ T-cell subsets in human peripheral blood. Though naive CD4+ T cells were readily converted to Foxp3+ T cells with TGF-β and IL-2 treatment in vitro, such Foxp3+ T cells did not express the memory marker CD45RO as do Foxp3+ T cells induced in the peripheral blood of Hepatitis B Virus (HBV) patients. Interestingly, a subset of human memory CD4+ T cells, defined as CD62L+ central memory T cells, could be induced by TGF-β to differentiate into Foxp3+ T cells. It is well known that Foxp3+ T cells derived from human CD4+CD25- T cells in vitro are lack suppressive functions. Our data about the suppressive functions of CD4+CD62L+ central memory T cell-derived Foxp3+ T cells support this conception, and an epigenetic analysis of these cells showed a similar methylation pattern in the FOXP3 Treg-specific demethylated region as the naive CD4+ T cell-derived Foxp3+ T cells. But further research showed that mouse CD4+ central memory T cells also could be induced to differentiate into Foxp3+ T cells, such Foxp3+ T cells could suppress the proliferation of effector T cells. Thus, our study identified CD4+CD62L+ central memory T cells as a novel potential source of iTreg. PMID:24155942

Sub-clonal analysis of the murine C1498 acute myeloid leukaemia cell line reveals genomic and immunogenic diversity.

PubMed

Driss, Virginie; Leprêtre, Frédéric; Briche, Isabelle; Mopin, Alexia; Villenet, Céline; Figeac, Martin; Quesnel, Bruno; Brinster, Carine

2017-12-01

In acute myeloid leukaemia (AML)-affected patients, the presence of heterogeneous sub-clones at diagnosis has been shown to be responsible for minimal residual disease and relapses. The role played by the immune system in this leukaemic sub-clonal hierarchy and maintenance remains unknown. As leukaemic sub-clone immunogenicity could not be evaluated in human AML xenograft models, we assessed the sub-clonal diversity of the murine C1498 AML cell line and the immunogenicity of its sub-clones in immune-competent syngeneic mice. The murine C1498 cell line was cultured in vitro and sub-clonal cells were generated after limiting dilution. The genomic profiles of 6 different sub-clones were analysed by comparative genomic hybridization arrays (CGH). The sub-clones were then injected into immune-deficient and - competent syngeneic mice. The immunogenicities of the sub-clones was evaluated through 1) assessment of mouse survival, 2) determination of leukaemic cell infiltration into organs by flow cytometry and the expression of a fluorescent reporter gene, 3) assessment of the CTL response ex vivo and 4) detection of residual leukaemic cells in the organs via amplification of the genomic reporter gene by real-time PCR (qPCR). Genomic analyses revealed heterogeneity among the parental cell line and its derived sub-clones. When injected individually into immune-deficient mice, all sub-clones induced cases of AML with different kinetics. However, when administered into immune-competent animals, some sub-clones triggered AML in which no mice survived, whereas others elicited reduced lethality rates. The AML-surviving mice presented efficient anti-leukaemia CTL activity ex vivo and eliminated the leukaemic cells in vivo. We showed that C1498 cell sub-clones presented genomic heterogeneity and differential immunogenicity resulting either in immune escape or elimination. Such findings could have potent implications for new immunotherapeutic strategies in patients with AML

In vitro toxicity assay of cisplatin on mouse acute lymphoblastic leukaemia and spermatogonial stem cells.

PubMed

Shabani, R; Ashtari, K; Behnam, B; Izadyar, F; Asgari, H; Asghari Jafarabadi, M; Ashjari, M; Asadi, E; Koruji, M

2016-06-01

Testicular cancer is the most common cancer affecting men in reproductive age, and cisplatin is one of the major helpful chemotherapeutic agents for treatment of this cancer. In addition, exposure of testes cancer cells to cisplatin could potentially eliminate tumour cells from germ cells in patients. The aim of this study was to evaluate the effect of cisplatin on viability of mouse acute lymphoblastic leukaemia cell line (EL-4) and neonatal mouse spermatogonial cells in vitro. In this study, the isolated spermatogonial stem cells (SSC) and EL-4 were divided into six groups including control (received medium), sham (received DMSO in medium) and experimental groups which received different doses of cisplatin (0.5, 5, 10 and 15 μg ml(-1) ). Cells viability was evaluated with MTT assay. The identity of the cultured cells was confirmed by the expression of specific markers. Our finding showed that viability of both SSC and EL-4 cells was reduced with the dose of 15 μg/ml when compared to the control group (P ≤ 0.05). Also, the differences between the IC50 in doses 10 and 15 μg/ml at different time were significant (P ≤ 0.05). The number of TUNEL-positive cells was increased, and the BAX and caspase-3 expressions were upregulated in EL4 cells for group that received an effective dose of cisplatin). In conclusion, despite the dramatic effects of cisplatin on both cells, spermatogonial stem cells could form colony in culture. © 2015 Blackwell Verlag GmbH.

Infusion of a non-HLA-matched ex-vivo expanded cord blood progenitor cell product after intensive acute myeloid leukaemia chemotherapy: a phase 1 trial.

PubMed

Delaney, Colleen; Milano, Filippo; Cicconi, Laura; Othus, Megan; Becker, Pamela S; Sandhu, Vicky; Nicoud, Ian; Dahlberg, Ann; Bernstein, Irwin D; Appelbaum, Frederick R; Estey, Elihu H

2016-07-01

The intensive chemotherapy regimens used to treat acute myeloid leukaemia routinely result in serious infections, largely due to prolonged neutropenia. We investigated the use of non-HLA-matched ex-vivo expanded cord blood progenitor cells to accelerate haemopoietic recovery and reduce infections after chemotherapy. We enrolled patients with a diagnosis of acute myeloid leukaemia by WHO criteria and aged 18-70 years inclusive at our institution (Fred Hutchinson Cancer Research Center) into this phase 1 trial. The primary endpoint of the study was safety of infusion of non-HLA-matched expanded cord blood progenitor cells after administration of clofarabine, cytarabine, and granulocyte-colony stimulating factor priming. The protocol is closed to accrual and analysis was performed per protocol. The trial is registered with ClinicalTrials.gov, NCT01031368. Between June 29, 2010, and June 26, 2012, 29 patients with acute myeloid leukaemia (19 newly diagnosed, ten relapsed or refractory) were enrolled. The most common adverse events were fever (27 [93%] of 29 patients) and infections (25 [86%] of 29 patients). We observed one case of acute infusional toxicity (attributed to an allergic reaction to dimethyl sulfoxide) in the 29 patients enrolled, who received 42 infusions of expanded progenitor cells. The following additional serious but expected adverse events were observed (each in one patient): grade 4 atrial fibrillation, grade 4 febrile neutropenia, lung infection with grade 4 absolute neutrophil count, colon infection with grade 4 absolute neutrophil count, grade 4 changed mental status, and one death from liver failure. No unexpected toxicity or graft-versus-host disease was observed. There was no evidence of in-vivo persistence of the expanded progenitor cell product in any patient beyond 14 days or induced alloimmunisation. Infusion of the expanded progenitor cell product seemed safe and might provide a promising treatment method for patients with acute myeloid

Premature cell senescence and T cell receptor-independent activation of CD8T cells in Juvenile Idiopathic Arthritis*

PubMed Central

Dvergsten, Jeffrey A.; Mueller, Robert G.; Griffin, Patricia; Abedin, Sameem; Pishko, Allyson; Michel, Joshua J.; Rosenkranz, Margalit E.; Reed, Ann M.; Kietz, Daniel A.; Vallejo, Abbe N.

2013-01-01

Objectives CD8T cells lacking CD28 were originally reported by Wedderburn and colleagues as a characteristic feature of JIA, but the relevance of these unusual cells to JIA remains to be elucidated. Because of recent evidence that CD28 loss is typical of terminally differentiated lymphocytes, we examined for functional subsets of CD8T cells in JIA. Methods Following informed consent/assent, blood and/or waste synovial fluid were collected from children with definite diagnosis of JIA (n = 98). De-identified blood (n = 33) and cord blood (n = 13) samples from healthy donors were also collected. CD8T and CD4T cells were screened for novel receptors, and where indicated, bioassays were performed to determine functional relevance of the identified receptor. Results Patients had a naïve T cell compartment with shortened telomeres, and their entire T cell pool had reduced proliferative capacity. They had an over abundance of CD31+CD28null CD8T cells, which was a significant feature of oligoarticular JIA (n = 62) compared to polyarticular JIA (n = 36). CD31+CD28null CD8T cells had limited mitotic capacity, and expressed high levels of the senescence antigens γH2Ax and/or p16. Ligation of CD31, independent of the TCR, sufficiently induced tyrosine phosphorylation, vesicle exocytosis, and production of IFN-γ and IL-10. Conclusion These data provide the first evidence for cell senescence, represented by CD31+CD28null CD8T cells, in the pathophysiology of JIA. Activation of these unusual cells in a TCR-independent manner suggests they are maladaptive, and could be potential targets for immunotherapy. PMID:23686519

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

MicroRNA-101 regulates T-cell acute lymphoblastic leukemia progression and chemotherapeutic sensitivity by targeting Notch1.

PubMed

Qian, Lu; Zhang, Wanggang; Lei, Bo; He, Aili; Ye, Lianhong; Li, Xingzhou; Dong, Xin

2016-11-01

The present study aimed to investigate the role of microRNA (miR)-101 in acute lymphoblastic leukemia progression and chemoresistance. Furthermore, a novel target gene of miR-101 was identified. Here, we confirmed that miR-101 was significantly downregulated in the blood samples of patients with T-cell acute lymphoblastic leukemia (T-ALL) compared with the healthy controls, as determined by reverse transcription quantitative polymerase chain reaction (RTqPCR) analysis. The in vitro experiments demonstrated that miR-101 significantly repressed the proliferation and invasion, and induced potent apoptosis in Jurkat cells, as determined by CCK-8, flow cytometer and cell invasion assays. Luciferase assay confirmed that Notch1 was a target gene of miR-101, and western blotting showed that miR-101 suppressed the expression of Notch1 at the protein level. Moreover, functional restoration assays revealed that Notch1 mediates the effects of miR-101 on Jurkat cell proliferation, apoptosis and invasion. miR-101 enhanced the sensitivity of Jurkat cells to the chemotherapeutic agent adriamycin. Taken together, our results show for the first time that miR-101 acts as a tumor suppressor in T-cell acute lymphoblastic leukaemia and it could enhance chemotherapeutic sensitivity. Furthermore, Notch1 was identified to be a novel target of miR-101. This study indicates that miR-101 may represent a potential therapeutic target for T-cell acute lymphoblastic leukemia intervention.

Integrins in T Cell Physiology

PubMed Central

Alabiso, Oscar; Galetto, Alessandra Silvia; Baldanzi, Gianluca

2018-01-01

From the thymus to the peripheral lymph nodes, integrin-mediated interactions with neighbor cells and the extracellular matrix tune T cell behavior by organizing cytoskeletal remodeling and modulating receptor signaling. LFA-1 (αLβ2 integrin) and VLA-4 (α4β1 integrin) play a key role throughout the T cell lifecycle from thymocyte differentiation to lymphocyte extravasation and finally play a fundamental role in organizing immune synapse, providing an essential costimulatory signal for the T cell receptor. Apart from tuning T cell signaling, integrins also contribute to homing to specific target organs as exemplified by the importance of α4β7 in maintaining the gut immune system. However, apart from those well-characterized examples, the physiological significance of the other integrin dimers expressed by T cells is far less understood. Thus, integrin-mediated cell-to-cell and cell-to-matrix interactions during the T cell lifespan still represent an open field of research. PMID:29415483

Adult T-Cell Leukemia/Lymphoma

MedlinePlus

... Adult T-Cell Leukemia/Lymphoma Adult T-Cell Leukemia/Lymphoma Adult T-cell A type of white ... immune responses by destroying harmful substances or cells. leukemia Disease generally characterized by the overproduction of abnormal ...

Deletion of Notch1 converts pro-T cells to dendritic cells and promotes thymic B cells by cell-extrinsic and cell-intrinsic mechanisms.

PubMed

Feyerabend, Thorsten B; Terszowski, Grzegorz; Tietz, Annette; Blum, Carmen; Luche, Hervé; Gossler, Achim; Gale, Nicholas W; Radtke, Freddy; Fehling, Hans Jörg; Rodewald, Hans-Reimer

2009-01-16

Notch1 signaling is required for T cell development and has been implicated in fate decisions in the thymus. We showed that Notch1 deletion in progenitor T cells (pro-T cells) revealed their latent developmental potential toward becoming conventional and plasmacytoid dendritic cells. In addition, Notch1 deletion in pro-T cells resulted in large numbers of thymic B cells, previously explained by T-to-B cell fate conversion. Single-cell genotyping showed, however, that the majority of these thymic B cells arose from Notch1-sufficient cells by a cell-extrinsic pathway. Fate switching nevertheless exists for a subset of thymic B cells originating from Notch1-deleted pro-T cells. Chimeric mice lacking the Notch ligand delta-like 4 (Dll4) in thymus epithelium revealed an essential role for Dll4 in T cell development. Thus, Notch1-Dll4 signaling fortifies T cell commitment by suppressing non-T cell lineage potential in pro-T cells, and normal Notch1-driven T cell development repels excessive B cells in the thymus.

T cell-B cell interactions in primary immunodeficiencies.

PubMed

Tangye, Stuart G; Deenick, Elissa K; Palendira, Umaimainthan; Ma, Cindy S

2012-02-01

Regulated interactions between cells of the immune system facilitate the generation of successful immune responses, thereby enabling efficient neutralization and clearance of pathogens and the establishment of both cell- and humoral-mediated immunological memory. The corollary of this is that impediments to efficient cell-cell interactions, normally necessary for differentiation and effector functions of immune cells, underly the clinical features and disease pathogenesis of primary immunodeficiencies. In affected individuals, these defects manifest as impaired long-term humoral immunity and susceptibility to infection by specific pathogens. In this review, we discuss the importance of, and requirements for, effective interactions between B cells and T cells during the formation of CD4(+) T follicular helper cells and the elicitation of cytotoxic function of virus-specific CD8(+) T cells, as well as how these processes are abrogated in primary immunodeficiencies due to loss-of-function mutations in defined genes. © 2012 New York Academy of Sciences.

Co-Expansion of Cytokine-Induced Killer Cells and Vγ9Vδ2 T Cells for CAR T-Cell Therapy

PubMed Central

Chen, Can; Tan, Wee-Kiat; Chi, Zhixia; Xu, Xue-Hu; Wang, Shu

2016-01-01

Gamma delta (γδ) T cells and cytokine-induced killer (CIK) cells, which are a heterogeneous population of T lymphocytes and natural killer T (NKT) cells, have been separately expanded ex vivo and shown to be capable of targeting and mediating cytotoxicity against various tumor cells in a major histocompatibility complex-unrestricted manner. However, the co-expansion and co-administration of these immune cells have not been explored. In this study we describe an efficient method to expand simultaneously both CIK and Vγ9Vδ2 T cells, termed as CIKZ cells, from human peripheral blood mononuclear cells (PBMCs) using Zometa, interferon-gamma (IFN-γ), interleukin 2 (IL-2), anti-CD3 antibody and engineered K562 feeder cells expressing CD64, CD137L and CD86. A 21-day culture of PBMCs with this method yielded nearly 20,000-fold expansion of CIKZ cells with γδ T cells making up over 20% of the expanded population. The expanded CIKZ cells exhibited antitumor cytotoxicity and could be modified to express anti-CD19 chimeric antigen receptor (CAR), anti-CEA CAR, and anti-HER2 CAR to enhance their specificity and cytotoxicity against CD19-, CEA-, or HER2-positive tumor cells. The tumor inhibitory activity of anti-CD19 CAR-modified CIKZ cells was further demonstrated in vivo in a Raji tumor mouse model. The findings herein substantiate the feasibility of co-expanding CIK and γδ cells for adoptive cellular immunotherapy applications such as CAR T-cell therapy against cancer. PMID:27598655

The BTK Inhibitor Ibrutinib (PCI-32765) Blocks Hairy Cell Leukaemia Survival, Proliferation and BCR Signalling: A New Therapeutic Approach

PubMed Central

Sivina, Mariela; Kreitman, Robert J.; Arons, Evgeny; Ravandi, Farhad; Burger, Jan A.

2014-01-01

B cell receptor (BCR) signalling plays a critical role in the progression of several B-cell malignancies, but its role in hairy cell leukaemia (HCL) is ambiguous. Bruton tyrosine kinase (BTK), a key player in BCR signalling, migration and adhesion, can be targeted with ibrutinib, a selective, irreversible BTK inhibitor. We analysed BTK expression and function in HCL and analysed the effects of ibrutinib on HCL cells. We demonstrated uniform BTK protein expression in HCL cells. Ibrutinib significantly inhibited HCL proliferation and cell cycle progression. Accordingly, ibrutinib also reduced HCL cell survival after BCR triggering with anti-immunoglobulins (A, G, and M) and abrogated the activation of kinases downstream of the BCR (PI3K and MAPK). Ibrutinib also inhibited BCR-dependent secretion of the chemokines CCL3 and CCL4 by HCL cells. Interestingly, ibrutinib inhibited CXCL12-induced signalling, a key pathway for bone marrow homing. Collectively, our data support the clinical development of ibrutinib in patients with HCL. PMID:24697238

T cell-dependent antibody production by Ly-1 B cells.

PubMed

Taki, S; Schmitt, M; Tarlinton, D; Förster, I; Rajewsky, K

1992-05-04

Through the use of a SCID transfer system, we have demonstrated that under certain conditions, the production of Ig by Ly-1 B cells can be modulated by T cells. This modulation can take the form of enhanced isotype production or isotype-switch induction and to some extent appears to be dependent on the activation state of the T cells. Furthermore we have shown that Ly-1 B cells can mount an idiotypically restricted T cell-dependent immune response to the antigen PC-KLH. This result suggests that the previous failure to observe T cell-dependent responses by Ly-1 B cells has been due to these B cells being "blind" to the antigens used and is not due to some inherent property of these B cells. When one considers the previous reports of the substantial contribution of Ly-1 B cells to the natural serum immunoglobulin levels and the ability of T cells to affect Ig production by Ly-1 B cells documented in this report, it is clear that the interaction of T cells with the Ly-1 B-cell population is important in determining the "natural" serum Ig repertoire of the mouse.

T-cell libraries allow simple parallel generation of multiple peptide-specific human T-cell clones.

PubMed

Theaker, Sarah M; Rius, Cristina; Greenshields-Watson, Alexander; Lloyd, Angharad; Trimby, Andrew; Fuller, Anna; Miles, John J; Cole, David K; Peakman, Mark; Sewell, Andrew K; Dolton, Garry

2016-03-01

Isolation of peptide-specific T-cell clones is highly desirable for determining the role of T-cells in human disease, as well as for the development of therapies and diagnostics. However, generation of monoclonal T-cells with the required specificity is challenging and time-consuming. Here we describe a library-based strategy for the simple parallel detection and isolation of multiple peptide-specific human T-cell clones from CD8(+) or CD4(+) polyclonal T-cell populations. T-cells were first amplified by CD3/CD28 microbeads in a 96U-well library format, prior to screening for desired peptide recognition. T-cells from peptide-reactive wells were then subjected to cytokine-mediated enrichment followed by single-cell cloning, with the entire process from sample to validated clone taking as little as 6 weeks. Overall, T-cell libraries represent an efficient and relatively rapid tool for the generation of peptide-specific T-cell clones, with applications shown here in infectious disease (Epstein-Barr virus, influenza A, and Ebola virus), autoimmunity (type 1 diabetes) and cancer. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Functional analysis of T cells expressing Ia antigens. I. Demonstration of helper T-cell heterogeneity.

PubMed

Swierkosz, J E; Marrack, P; Kappler, J W

1979-12-01

We have examined the expression of I-region antigens on functional subpopulations of murine T cells. A.TH anti-A.TL (anti-Ik, Sk, Gk) alloantiserum was raised by immunization of recipients with concanavalin A (Con A) stimulated thymic and peripheral T-cell blasts. In contrast to similar antisera made by conventional methods, the anti-Ia blast serum was highly cytotoxic for purified T lymphocytes. Moreover, it reacted in a specific fashion with T cells having particular functions. Treatment of keyhole limpet hemocyanin (KLH)-primed B10.A (H-2 alpha) T cells with this antiserum plus complement resulted in the elimination of helper activity for B-cell responses to trinitrophenyl-KLH. Inhibition was shown to be a result of the selective killing of one type of helper T cell whose activity could be replaced by a factor(s) found in the supernate of Con A-activated spleen cells. A second type of helper cell required for responses to protein-bound antigens appeared to be Ia-. By absorption and analysis on H-2 recombinants, at least two specificities were detectable on helper T cells; one mapping in the I-A subregion and a second in a region(s) to the right of I-J. In addition, the helper T cell(s) involved in the generation of alloreactive cytotoxic lymphocytes was shown to be Ia+, whereas cytotoxic effector cells and their precursors were Ia- with this antiserum. These results provide strong evidence for the selective expression of I-region determinants on T-cell subsets and suggest that T-cell-associated Ia antigens may play an important role in T-lymphocyte function.

T Cell Phenotype and T Cell Receptor Repertoire in Patients with Major Depressive Disorder

PubMed Central

Patas, Kostas; Willing, Anne; Demiralay, Cüneyt; Engler, Jan Broder; Lupu, Andreea; Ramien, Caren; Schäfer, Tobias; Gach, Christian; Stumm, Laura; Chan, Kenneth; Vignali, Marissa; Arck, Petra C.; Friese, Manuel A.; Pless, Ole; Wiedemann, Klaus; Agorastos, Agorastos; Gold, Stefan M.

2018-01-01

While a link between inflammation and the development of neuropsychiatric disorders, including major depressive disorder (MDD) is supported by a growing body of evidence, little is known about the contribution of aberrant adaptive immunity in this context. Here, we conducted in-depth characterization of T cell phenotype and T cell receptor (TCR) repertoire in MDD. For this cross-sectional case–control study, we recruited antidepressant-free patients with MDD without any somatic or psychiatric comorbidities (n = 20), who were individually matched for sex, age, body mass index, and smoking status to a non-depressed control subject (n = 20). T cell phenotype and repertoire were interrogated using a combination of flow cytometry, gene expression analysis, and next generation sequencing. T cells from MDD patients showed significantly lower surface expression of the chemokine receptors CXCR3 and CCR6, which are known to be central to T cell differentiation and trafficking. In addition, we observed a shift within the CD4+ T cell compartment characterized by a higher frequency of CD4+CD25highCD127low/− cells and higher FOXP3 mRNA expression in purified CD4+ T cells obtained from patients with MDD. Finally, flow cytometry-based TCR Vβ repertoire analysis indicated a less diverse CD4+ T cell repertoire in MDD, which was corroborated by next generation sequencing of the TCR β chain CDR3 region. Overall, these results suggest that T cell phenotype and TCR utilization are skewed on several levels in patients with MDD. Our study identifies putative cellular and molecular signatures of dysregulated adaptive immunity and reinforces the notion that T cells are a pathophysiologically relevant cell population in this disorder. PMID:29515587

Effectiveness of imatinib mesylate over etoposide in the treatment of sensitive and resistant chronic myeloid leukaemia cells in vitro.

PubMed

Husaini, Roslina; Ahmad, Munirah; Zakaria, Zubaidah

2017-06-01

Chronic myeloid leukaemia (CML) is a form of leukaemia derived from the myeloid cell lineage. Imatinib mesylate, the breakpoint cluster region-abelson murine leukeamia kinase inhibitor, is a specific reagent used in the clinical treatment of CML. The DNA topoisomerase II inhibitor, etoposide, is also employed as a therapeutic, though it is used to a lesser extent. The present study aims to evaluate the effects of CML-targeted therapy, utilising imatinib mesylate and etoposide in the in vitro treatment of parental sensitive and adriamycin-resistant CML in the K562 and K562/ADM cell lines, respectively. Preliminary work involved the screening of multidrug resistant (MDR) gene expression, including MDR1, MRP1 and B-cell lymphoma 2 (BCL-2) at the mRNA levels. The sensitive and resistant CML cell lines expressed the MRP1 gene, though the sensitive K562 cells expressed low, almost undetectable levels of MDR1 and BCL-2 genes relative to the K562/ADM cells. Following treatment with imatinib mesylate or etoposide, the IC50 for imatinib mesylate did not differ between the sensitive and resistant cell lines (0.492±0.024 and 0.378±0.029, respectively), indicating that imatinib mesylate is effective in the treatment of CML regardless of cell chemosensitivity. However, the IC50 for etoposide in sensitive K562 cells was markedly lower than that of K562/ADM cells (50.6±16.5 and 194±8.46 µM, respectively), suggesting that the higher expression levels of MDR1 and/or BCL-2 mRNA in resistant cells may be partially responsible for this effect. This is supported by terminal deoxynucleotidyl transferase dUTP nick-end labeling data, whereby a higher percentage of apoptotic cells were found in the sensitive and resistant K562 cells treated with imatinib mesylate (29.3±0.2 and 31.9±16.7%, respectively), whereas etoposide caused significant apoptosis of sensitive K562 cells (18.3±8.35%) relative to K562/ADM cells (5.17±3.3%). In addition, the MDR genes in K562/ADM cells were knocked

Foxp3+ regulatory T cells impede the priming of protective CD8+ T cells

PubMed Central

Ertelt, James M.; Rowe, Jared H.; Mysz, Margaret A.; Singh, Charanjeet; Roychowdhury, Monika; Aguilera, Marijo N.; Way, Sing Sing

2011-01-01

T cell activation is controlled by incompletely defined opposing stimulation and suppression signals that together sustain the balance between optimal host defense against infection and peripheral tolerance. Herein, we explored the impacts of Foxp3+ regulatory T cell (Treg) suppression in priming antigen-specific T cell activation under non-infection and infection conditions. We find the transient ablation of Foxp3+ Tregs unleashes the robust expansion and activation of peptide stimulated CD8+ T cells that provide protection against Listeria monocytogenes (Lm) infection in an antigen-specific fashion. By contrast, Treg-ablation had non-significant impacts on the CD8+ T cell response primed by infection with recombinant Lm. Similarly, non-recombinant Lm administered with peptide stimulated the expansion and activation of CD8+ T cells that paralleled the response primed by Treg-ablation. Interestingly, these adjuvant properties of Lm did not require CD8+ T cell stimulation by IL-12 produced in response to infection, but instead were associated with sharp reductions in Foxp3+ Treg suppressive potency. Therefore, Foxp3+ Tregs impose critical barriers that when overcome naturally during infection or artificially with ablation allows the priming of protective antigen-specific CD8+ T cells. PMID:21810602

ETV6-RUNX1 + Acute Lymphoblastic Leukaemia in Identical Twins.

PubMed

Ford, Anthony M; Greaves, Mel

2017-01-01

Acute leukaemia is the major subtype of paediatric cancer with a cumulative risk of 1 in 2000 for children up to the age of 15 years. Childhood acute lymphoblastic leukaemia (ALL) is a biologically and clinically diverse disease with distinctive subtypes; multiple chromosomal translocations exist within the subtypes and each carries its own prognostic relevance. The most common chromosome translocation observed is the t(12;21) that results in an in-frame fusion between the first five exons of ETV6 (TEL) and almost the entire coding region of RUNX1 (AML1).The natural history of childhood ALL is almost entirely clinically silent and is well advanced at the point of diagnosis. It has, however, been possible to backtrack this process through molecular analysis of appropriate clinical samples: (i) leukaemic clones in monozygotic twins that are either concordant or discordant for ALL; (ii) archived neonatal blood spots or Guthrie cards from individuals who later developed leukaemia; and (iii) stored, viable cord blood cells.Here, we outline our studies on the aetiology and pathology of childhood ALL that provide molecular evidence for a monoclonal, prenatal origin of ETV6-RUNX1+ leukaemia in monozygotic identical twins. We provide mechanistic support for the concept that altered patterns of infection during early childhood can deliver the necessary promotional drive for the progression of ETV6-RUNX1+ pre-leukaemic cells into a postnatal overt leukaemia.

T cell costimulation by chemokine receptors.

PubMed

Molon, Barbara; Gri, Giorgia; Bettella, Monica; Gómez-Moutón, Concepción; Lanzavecchia, Antonio; Martínez-A, Carlos; Mañes, Santos; Viola, Antonella

2005-05-01

Signals mediated by chemokine receptors may compete with T cell receptor stop signals and determine the duration of T cell-antigen-presenting cell interactions. Here we show that during T cell stimulation by antigen-presenting cells, T cell chemokine receptors coupled to G(q) and/or G(11) protein were recruited to the immunological synapse by a G(i)-independent mechanism. When chemokine receptors were sequestered at the immunological synapse, T cells became insensitive to chemotactic gradients, formed more stable conjugates and finally responded with enhanced proliferation and cytokine production. We suggest that chemokine receptor trapping at the immunological synapse enhances T cell activation by improving T cell-antigen-presenting cell attraction and impeding the 'distraction' of successfully engaged T cells by other chemokine sources.

Memory T cells and vaccines.

PubMed

Esser, Mark T; Marchese, Rocio D; Kierstead, Lisa S; Tussey, Lynda G; Wang, Fubao; Chirmule, Narendra; Washabaugh, Michael W

2003-01-17

T lymphocytes play a central role in the generation of a protective immune response in many microbial infections. After immunization, dendritic cells take up microbial antigens and traffic to draining lymph nodes where they present processed antigens to naïve T cells. These naïve T cells are stimulated to proliferate and differentiate into effector and memory T cells. Activated, effector and memory T cells provide B cell help in the lymph nodes and traffic to sites of infection where they secrete anti-microbial cytokines and kill infected cells. At least two types of memory cells have been defined in humans based on their functional and migratory properties. T central-memory (T(CM)) cells are found predominantly in lymphoid organs and can not be immediately activated, whereas T effector-memory (T(EM)) cells are found predominantly in peripheral tissue and sites of inflammation and exhibit rapid effector function. Most currently licensed vaccines induce antibody responses capable of mediating long-term protection against lytic viruses such as influenza and small pox. In contrast, vaccines against chronic pathogens that require cell-mediated immune responses to control, such as malaria, Mycobacterium tuberculosis (TB), human immunodeficiency virus (HIV) and hepatitis C virus (HCV), are currently not available or are ineffective. Understanding the mechanisms by which long-lived cellular immune responses are generated following vaccination should facilitate the development of safe and effective vaccines against these emerging diseases. Here, we review the current literature with respect to memory T cells and their implications to vaccine development.

Effector CD8 T cells dedifferentiate into long-lived memory cells.

PubMed

Youngblood, Ben; Hale, J Scott; Kissick, Haydn T; Ahn, Eunseon; Xu, Xiaojin; Wieland, Andreas; Araki, Koichi; West, Erin E; Ghoneim, Hazem E; Fan, Yiping; Dogra, Pranay; Davis, Carl W; Konieczny, Bogumila T; Antia, Rustom; Cheng, Xiaodong; Ahmed, Rafi

2017-12-21

Memory CD8 T cells that circulate in the blood and are present in lymphoid organs are an essential component of long-lived T cell immunity. These memory CD8 T cells remain poised to rapidly elaborate effector functions upon re-exposure to pathogens, but also have many properties in common with naive cells, including pluripotency and the ability to migrate to the lymph nodes and spleen. Thus, memory cells embody features of both naive and effector cells, fuelling a long-standing debate centred on whether memory T cells develop from effector cells or directly from naive cells. Here we show that long-lived memory CD8 T cells are derived from a subset of effector T cells through a process of dedifferentiation. To assess the developmental origin of memory CD8 T cells, we investigated changes in DNA methylation programming at naive and effector cell-associated genes in virus-specific CD8 T cells during acute lymphocytic choriomeningitis virus infection in mice. Methylation profiling of terminal effector versus memory-precursor CD8 T cell subsets showed that, rather than retaining a naive epigenetic state, the subset of cells that gives rise to memory cells acquired de novo DNA methylation programs at naive-associated genes and became demethylated at the loci of classically defined effector molecules. Conditional deletion of the de novo methyltransferase Dnmt3a at an early stage of effector differentiation resulted in reduced methylation and faster re-expression of naive-associated genes, thereby accelerating the development of memory cells. Longitudinal phenotypic and epigenetic characterization of the memory-precursor effector subset of virus-specific CD8 T cells transferred into antigen-free mice revealed that differentiation to memory cells was coupled to erasure of de novo methylation programs and re-expression of naive-associated genes. Thus, epigenetic repression of naive-associated genes in effector CD8 T cells can be reversed in cells that develop into long

Hairy cell leukaemia complicated by anti-MAG paraproteinemic demyelinating neuropathy: resolution of neurological syndrome after cladribrine treatment.

PubMed

Rossi, Davide; Franceschetti, Silvia; Cerri, Michaela; Conconi, Annarita; Lunghi, Monia; Capello, Daniela; Cantello, Roberto; Gaidano, Gianluca

2007-06-01

Hairy cell leukaemia (HCL) occasionally displays a monoclonal gammopathy, yet the association of HCL with paraproteinemic demyelinating neuropathy (PDN) has not been reported. We describe a HCL case complicated by PDN and high titers of monoclonal IgM against myelin associated glycoprotein (MAG). Heavy and light chains of the patient's anti-MAG monoclonal protein were consistent with those expressed by HCL cells. After treatment with cladribrine, remission of HCL strictly paralleled disappearance of the IgM monoclonal protein and of the serum anti-MAG activity, and led to PDN clinical and electrophysiological improvement. Purine analogs may represent a choice in IgM PDN associated with lymphoproliferative disorders.

Promyelocytic leukaemia zinc finger maintains self-renewal of male germline stem cells (mGSCs) and its expression pattern in dairy goat testis.

PubMed

Song, W; Zhu, H; Li, M; Li, N; Wu, J; Mu, H; Yao, X; Han, W; Liu, W; Hua, J

2013-08-01

Previous studies have shown that promyelocytic leukaemia zinc finger (PLZF) is a spermatogonia-specific transcription factor in the testis, required to regulate self-renewal and maintenance of the spermatogonia stem cell. Up to now, expression and function of PLZF in the goat testis has not been known. The objectives of this study were to investigate PLZF expression pattern in the dairy goat and its effect on male goat germline stem cell (mGSC) self-renewal and differentiation. Testis development and expression patterns of PLZF in the dairy goat were analysed by haematoxylin and eosin staining, immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR). Furthermore, effects of PLZF overexpression on mGSC self-renewal and differentiation were evaluated by quantitative RT-PCR (QRT-PCR), immunofluorescence and BrdU incorporation assay. Promyelocytic leukaemia zinc finger was essential for dairy goat testis development and expression of several proliferation and pluripotency-associated proteins including OCT4, C-MYC were upregulated by PLZF overexpression. The study demonstrated that PLZF played a key role in maintaining self-renewal of mGSCs and its overexpression enhanced expression of proliferation-associated genes. Promyelocytic leukaemia zinc finger could function in the dairy goat as well as in other species in maintaining self-renewal of germline stem cells and this study provides a model to study the mechanism on self-renewal and differentiation of mGSCs in livestock. © 2013 John Wiley & Sons Ltd.

Expression of activating natural killer-cell receptors is a hallmark of the innate-like T-cell neoplasm in peripheral T-cell lymphomas.

PubMed

Uemura, Yu; Isobe, Yasushi; Uchida, Akiko; Asano, Junko; Nishio, Yuji; Sakai, Hirotaka; Hoshikawa, Masahiro; Takagi, Masayuki; Nakamura, Naoya; Miura, Ikuo

2018-04-01

Peripheral T- or natural killer (NK)-cell lymphomas are rare and difficult-to-recognize diseases. It remains arduous to distinguish between NK cell- and cytotoxic T-lymphocyte-derived lymphomas through routine histological evaluation. To clarify the cells of origin, we focused on NK-cell receptors and examined the expression using immunohistochemistry in 22 cases with T- and NK-cell neoplasms comprising angioimmunoblastic T-cell lymphoma, anaplastic lymphoma kinase (ALK)-positive and -negative anaplastic large-cell lymphomas, extranodal NK/T-cell lymphoma, nasal type, monomorphic epitheliotropic intestinal T-cell lymphoma, aggressive NK-cell leukemia, and other peripheral T-cell lymphomas. Inhibitory receptor leukocyte immunoglobulin-like receptor subfamily B member 1 (LILRB1) was detected in 14 (64%) cases, whereas activating receptors DNAM1, NKp46, and NKG2D were expressed in 7 (32%), 9 (41%), and 5 (23%) cases, respectively. Although LILRB1 was detected regardless of the disease entity, the activating NK-cell receptors were expressed predominantly in TIA-1-positive neoplasms (DNAM1, 49%; NKp46, 69%; and NKG2D, 38%). In addition, NKp46 and NKG2D were detected only in NK-cell neoplasms and cytotoxic T-lymphocyte-derived lymphomas including monomorphic epitheliotropic intestinal T-cell lymphoma. One Epstein-Barr virus-harboring cytotoxic T-lymphocyte-derived lymphoma mimicking extranodal NK/T-cell lymphoma, nasal type lacked these NK-cell receptors, indicating different cell origin from NK and innate-like T cells. Furthermore, NKG2D expression showed a negative impact on survival among the 22 examined cases, which mainly received the standard chemotherapy regimen (log-rank test, P = .024). We propose that the presence of activating NK-cell receptors may provide new insights into understanding peripheral T-cell lymphomas and characterizing them as innate-like T-cell neoplasm. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on

Chronic lymphocytic leukaemia

PubMed Central

Kipps, Thomas J.; Stevenson, Freda K.; Wu, Catherine J.; Croce, Carlo M.; Packham, Graham; Wierda, William G.; O’Brien, Susan; Gribben, John; Rai, Kanti

2017-01-01

Chronic lymphocytic leukaemia (CLL) is a malignancy of CD5+ B cells that is characterized by the accumulation of small, mature-appearing lymphocytes in the blood, marrow and lymphoid tissues. Signalling via surface immunoglobulin, which constitutes the major part of the B cell receptor, and several genetic alterations play a part in CLL pathogenesis, in addition to interactions between CLL cells and other cell types, such as stromal cells, T cells and nurse-like cells in the lymph nodes. The clinical progression of CLL is heterogeneous and ranges from patients who require treatment soon after diagnosis to others who do not require therapy for many years, if at all. Several factors, including the immunoglobulin heavy-chain variable region gene (IGHV) mutational status, genomic changes, patient age and the presence of comorbidities, should be considered when defining the optimal management strategies, which include chemotherapy, chemoimmunotherapy and/or drugs targeting B cell receptor signalling or inhibitors of apoptosis, such as BCL-2. Research on the biology of CLL has profoundly enhanced our ability to identify patients who are at higher risk for disease progression and our capacity to treat patients with drugs that selectively target distinctive phenotypic or physiological features of CLL. How these and other advances have shaped our current understanding and treatment of patients with CLL is the subject of this Primer. PMID:28102226

Anti-inflammatory effects of Artemisia princeps in antigen-stimulated T cells and regulatory T cells.

PubMed

Chang, Sung Ho; Jung, Eun Jung; Park, Youn Hee; Lim, Dong Gyun; Ko, Na Young; Choi, Wahn Soo; Her, Erk; Kim, Soo Hyun; Choi, Kang Duk; Bae, Jae Ho; Kim, Sun Hee; Kang, Chi Dug; Han, Duck Jong; Kim, Song Cheol

2009-08-01

The aim was to investigate the anti-inflammatory effects of Artemisia princeps extract on the activity of anti-CD3/CD28-stimulated CD4(+)CD25(-) T cells and antigen-expanded regulatory T cells. CD4(+)CD25(-) T cells were activated with coated anti-CD3 and anti-CD28 and cultured in the presence or absence of various concentrations of A. princeps extract. The cultures were pulsed on Day 6 with [(3)H]thymidine and, after harvesting the cells, [(3)H]thymidine incorporation was measured. For analysis of interleukin-2 and interferon-gamma secreted from CD4(+)CD25(-) T cells, culture supernatants were collected on Days 2 and 6. For the analysis of interleukin-10 secreted from the CD4(+)CD25(-) T cells and expanded regulatory T cells, supernatants were collected after 2 and 7 days, respectively. Cytokine levels were determined using an enzyme-linked immunosorbent assay. Potential medicinal components of the A. princeps extract were determined using gas chromatography-mass spectrometry. A. princeps (30 microg/ml) effectively suppressed proliferation of CD4(+)CD25(-) T cells that were stimulated with anti-CD3/CD28 without causing cytotoxicity in spleen cells incubated under conditions lacking antigen stimulation. A. princeps inhibited production of the pro-inflammatory cytokines interleukin-2 and interferon-gamma in anti-CD3/CD28-stimulated CD4(+)CD25(-) T cells. Also, the extract slightly increased production of the anti-inflammatory cytokine interleukin-10 in these cells. In regulatory T cells expanded by anti-CD3/CD28, A. princeps increased production of interleukin-10 and Foxp3. The results suggest that A. princeps may be useful in the treatment of autoimmune diseases and organ transplantation rejection by inhibiting proliferation of inflammatory T cells, suppressing inflammatory processes in antigen-stimulated CD4(+)CD25(-) T cells and increasing activity of expanded regulatory T cells.

Asymmetric cell division during T cell development controls downstream fate

PubMed Central

Pham, Kim; Shimoni, Raz; Charnley, Mirren; Ludford-Menting, Mandy J.; Hawkins, Edwin D.; Ramsbottom, Kelly; Oliaro, Jane; Izon, David; Ting, Stephen B.; Reynolds, Joseph; Lythe, Grant; Molina-Paris, Carmen; Melichar, Heather; Robey, Ellen; Humbert, Patrick O.; Gu, Min

2015-01-01

During mammalian T cell development, the requirement for expansion of many individual T cell clones, rather than merely expansion of the entire T cell population, suggests a possible role for asymmetric cell division (ACD). We show that ACD of developing T cells controls cell fate through differential inheritance of cell fate determinants Numb and α-Adaptin. ACD occurs specifically during the β-selection stage of T cell development, and subsequent divisions are predominantly symmetric. ACD is controlled by interaction with stromal cells and chemokine receptor signaling and uses a conserved network of polarity regulators. The disruption of polarity by deletion of the polarity regulator, Scribble, or the altered inheritance of fate determinants impacts subsequent fate decisions to influence the numbers of DN4 cells arising after the β-selection checkpoint. These findings indicate that ACD enables the thymic microenvironment to orchestrate fate decisions related to differentiation and self-renewal. PMID:26370500

The GIT–PIX complexes regulate the chemotactic response of rat basophilic leukaemia cells

PubMed Central

Gavina, Manuela; Za, Lorena; Molteni, Raffaella; Pardi, Ruggero; Curtis, Ivan de

2009-01-01

Background information. Cell motility entails the reorganization of the cytoskeleton and membrane trafficking for effective protrusion. The GIT–PIX protein complexes are involved in the regulation of cell motility and adhesion and in the endocytic traffic of members of the family of G-protein-coupled receptors. We have investigated the function of the endogenous GIT complexes in the regulation of cell motility stimulated by fMLP (formyl-Met-Leu-Phe) peptide, in a rat basophilic leukaemia RBL-2H3 cell line stably expressing an HA (haemagglutinin)-tagged receptor for the fMLP peptide. Results. Our analysis shows that RBL cells stably transfected with the chemoattractant receptor expressed both GIT1–PIX and GIT2–PIX endogenous complexes. We have used silencing of the different members of the complex by small interfering RNAs to study the effects on a number of events linked to agonist-induced cell migration. We found that cell adhesion was not affected by depletion of any of the proteins of the GIT complex, whereas agonist-enhanced cell spreading was inhibited. Analysis of agonist-stimulated haptotactic cell migration indicated a specific positive effect of GIT1 depletion on trans-well migration. The internalization of the formyl-peptide receptor was also inhibited by depletion of GIT1 and GIT2. The effects of the GIT complexes on trafficking of the receptors was confirmed by an antibody-enhanced agonist-induced internalization assay, showing that depletion of PIX, GIT1 or GIT2 protein caused decreased perinuclear accumulation of internalized receptors. Conclusions. Our results show that endogenous GIT complexes are involved in the regulation of chemoattractant-induced cell motility and receptor trafficking, and support previous findings indicating an important function of the GIT complexes in the regulation of different G-protein-coupled receptors. Our results also indicate that endogenous GIT1 and GIT2 regulate distinct subsets of agonist-induced responses and

Ability of γδ T cells to modulate the Foxp3 T cell response is dependent on adenosine.

PubMed

Liang, Dongchun; Woo, Jeong-Im; Shao, Hui; Born, Willi K; O'Brien, Rebecca L; Kaplan, Henry J; Sun, Deming

2018-01-01

Whether γδ T cells inhibit or enhance the Foxp3 T cell response depends upon their activation status. The critical enhancing effector in the supernatant is adenosine. Activated γδ T cells express adenosine receptors at high levels, which enables them to deprive Foxp3+ T cells of adenosine, and to inhibit their expansion. Meanwhile, cell-free supernatants of γδ T cell cultures enhance Foxp3 T cell expansion. Thus, inhibition and enhancement by γδ T cells of Foxp3 T cell response are a reflection of the balance between adenosine production and absorption by γδ T cells. Non-activated γδ T cells produce adenosine but bind little, and thus enhance the Foxp3 T cell response. Activated γδ T cells express high density of adenosine receptors and have a greatly increased ability to bind adenosine. Extracellular adenosine metabolism and expression of adenosine receptor A2ARs by γδ T cells played a major role in the outcome of γδ and Foxp3 T cell interactions. A better understanding of the functional conversion of γδ T cells could lead to γδ T cell-targeted immunotherapies for related diseases.

Granulocyte-macrophage colony-stimulating factor induces the differentiation of murine erythroleukaemia cells into dendritic cells.

PubMed Central

Cao, X; Zhao, Y; Yu, Y; Wang, Y; Zhang, M; Zhang, W; Wang, J

1998-01-01

Dendritic cells (DC) are professional antigen-presenting cells (APC) within the immune system and antigen-pulsed DC can be used as an effective vaccine for active immunotherapy of cancer. Granulocyte-macrophage colony-stimulating factor (GM-CSF) plays an important role in the generation of DC. We previously showed that GM-CSF can induce murine erythroleukaemia cells (FBL-3) to differentiate into monocyte-like cells. To develop a new vaccinating method to stimulate the host immune response to leukaemia, we further investigate whether FBL-3 cells induced by GM-CSF can differentiate into DC in the present study. After being treated with GM-CSF, FBL-3 cells expressed high levels of 33D1 and NLDC-145, which are the specific markers of DC. The expression of MHC-II, B7-1, B7-2 and vascular cell adhesion molecule-1 (VCAM-1) was up-regulated markedly; the typical morphology of DC were also observed by electron microscopy. Functionally, the GM-CSF-induced FBL-3 cells could apparently stimulate the proliferation of naive allogeneic and autologous T lymphocytes and induce the generation of specific CTL more efficiently than the wild-type FBL-3 cells. Mice immunized with GM-CSF-induced FBL-3 cells could resist the subsequent challenge with the wild-type FBL-3 cells. Collectively, these data indicate that GM-CSF differentiates murine erythroleukaemia cells into DC phenotypically, morphologically and functionally. FBL-3-derived DC can be used as a new type of vaccine. Our results may have important implications for the immunotherapy of leukaemia. Images Figure 3 Figure 4 PMID:9767469

Angioimmunoblastic T-cell lymphoma: more than a disease of T follicular helper cells.

PubMed

Lemonnier, François; Mak, Tak W

2017-08-01

Angioimmunoblastic T-cell lymphoma (AITL) is one of the most frequent entities of peripheral T-cell lymphoma. An AITL has two components: the AITL tumour cells, which have a T follicular helper (TFH) cell phenotype, and a surrounding and extensive tumour microenvironment that is populated with various reactive cell types, including B cells. Recurrent TET2 mutations have been described in 50-80% of AITLs, possibly occurring in a haematopoietic progenitor cell. An article published recently in the Journal of Pathology describes the use of microdissection to isolate PD1 + AITL tumour cells and CD20 + B cells from the AITL microenvironment, and to show that TET2 mutations are actually more frequent in these diseases than previously thought. Whereas TET2 mutations were detected in only six of 13 AITLs, 12 of 13 samples of microdissected PD1 + AITL tumour cells possessed this mutation. Moreover, TET2 mutations were detected in CD20 + B cells from the AITL microenvironment in six of nine informative cases. These results confirm that TET2 mutation is an early event in the majority of AITL cases, and that the driving molecular anomalies are not restricted to the T lineage tumour cells. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

RUNX3 is involved in caspase-3-dependent apoptosis induced by a combination of 5-aza-CdR and TSA in leukaemia cell lines.

PubMed

Zhai, Feng-Xian; Liu, Xiang-Fu; Fan, Rui-Fang; Long, Zi-Jie; Fang, Zhi-Gang; Lu, Ying; Zheng, Yong-Jiang; Lin, Dong-Jun

2012-03-01

Epigenetic therapy has had a significant impact on the management of haematologic malignancies. The aim of this study was to assess whether 5-aza-CdR and TSA inhibit the growth of leukaemia cells and induce caspase-3-dependent apoptosis by upregulating RUNX3 expression. K562 and Reh cells were treated with 5-aza-CdR, TSA or both compounds. RT-PCR and Western blot analyses were used to examine the expression of RUNX3 at the mRNA and protein levels, respectively. Immunofluorescence microscopy was used to detect the cellular location of RUNX3. Additionally, after K562 cells were transfected with RUNX3, apoptosis and proliferation were studied using Annexin V staining and MTT assays. The expression of RUNX3 in leukaemia cell lines was markedly less than that in the controls. Demethylating drug 5-aza-CdR could induce RUNX3 expression, but the combination of TSA and 5-aza-CdR had a greater effect than did treatment with a single compound. The combination of 5-aza-CdR and TSA induced the translocation of RUNX3 from the cytoplasm into the nucleus. TSA enhanced apoptosis induced by 5-aza-CdR, and Annexin V and Hoechst 33258 staining showed that the combination induced apoptosis but not necrosis. Furthermore, apoptosis was dependent on the caspase-3 pathway. RUNX3 overexpression in K562 cells led to growth inhibition and apoptosis and potentiated the effects of 5-aza-CdR induction. RUNX3 plays an important role in leukaemia cellular functions, and the induction of RUNX3-mediated effects may contribute to the therapeutic value of combination TSA and 5-aza-CdR treatment.

Nutritional effects on T-cell immunometabolism

PubMed Central

Cohen, Sivan; Danzaki, Keiko; MacIver, Nancie J.

2017-01-01

T cells are highly influenced by nutrient uptake from their environment, and changes in overall nutritional status, such as malnutrition or obesity, can result in altered T-cell metabolism and behavior. In states of severe malnutrition or starvation, T-cell survival, proliferation, and inflammatory cytokine production are all decreased, as is T-cell glucose uptake and metabolism. The altered T-cell function and metabolism seen in malnutrition is associated with altered adipokine levels, most particularly decreased leptin. Circulating leptin levels are low in malnutrition, and leptin has been shown to be a key link between nutrition and immunity. The current view is that leptin signaling is required to upregulate activated T-cell glucose metabolism and thereby fuel T-cell activation. In the setting of obesity, T cells have been found to have a key role in promoting the recruitment of inflammatory macrophages to adipose depots along with the production of inflammatory cytokines that promote the development of insulin resistance leading to diabetes. Deletion of T cells, key T-cell transcription factors, or pro-inflammatory T-cell cytokines prevents insulin resistance in obesity and underscores the importance of T cells in obesity-associated inflammation and metabolic disease. Altogether, T cells have a critical role in nutritional immunometabolism. PMID:28054344

Suppression of pro-inflammatory T-cell responses by human mesothelial cells.

PubMed

Lin, Chan-Yu; Kift-Morgan, Ann; Moser, Bernhard; Topley, Nicholas; Eberl, Matthias

2013-07-01

Human γδ T cells reactive to the microbial metabolite (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP) contribute to acute inflammatory responses. We have previously shown that peritoneal dialysis (PD)-associated infections with HMB-PP producing bacteria are characterized by locally elevated γδ T-cell frequencies and poorer clinical outcome compared with HMB-PP negative infections, implying that γδ T cells may be of diagnostic, prognostic and therapeutic value in acute disease. The regulation by local tissue cells of these potentially detrimental γδ T-cell responses remains to be investigated. Freshly isolated γδ or αβ T cells were cultured with primary mesothelial cells derived from omental tissue, or with mesothelial cell-conditioned medium. Stimulation of cytokine production and proliferation by peripheral T cells in response to HMB-PP or CD3/CD28 beads was assessed by flow cytometry. Resting mesothelial cells were potent suppressors of pro-inflammatory γδ T cells as well as CD4+ and CD8+ αβ T cells. The suppression of γδ T-cell responses was mediated through soluble factors released by primary mesothelial cells and could be counteracted by SB-431542, a selective inhibitor of TGF-β and activin signalling. Recombinant TGF-β1 but not activin-A mimicked the mesothelial cell-mediated suppression of γδ T-cell responses to HMB-PP. The present findings indicate an important regulatory function of mesothelial cells in the peritoneal cavity by dampening pro-inflammatory T-cell responses, which may help preserve the tissue integrity of the peritoneal membrane in the steady state and possibly during the resolution of acute inflammation.

Dendritic cells in chronic myelomonocytic leukaemia.

PubMed

Vuckovic, S; Fearnley, D B; Gunningham, S; Spearing, R L; Patton, W N; Hart, D N

1999-06-01

Blood dendritic cells (DC) differentiate in vitro via two separate pathways: either directly from blood DC precursors (DCp) or from CD14+ monocytes. In chronic myelomonocytic leukaemia (CMML) abnormal bone marrow precursors contribute to blood monocyte development but DC development has not been studied previously. Monocytes comprised 60% of blood MNC in 15 CMML patients studied, compared with 20% in 16 age-matched controls. The increase in blood monocytes was accompanied by a reciprocal decrease in mean blood DC percentage (from 0.42% of MNC in normal individuals to 0.16% of MNC in CMML patients). Absolute blood DC numbers showed a minimal (non-significant) reduction from 9.8 x 10(6)/l in normal individuals to 7.5 x 10(6)/l in CMML patients. The CD14(low) WCD16+ monocyte subpopulation was not found in CMML patients. After culture in GM-CSF/IL-4, CMML CD14+ monocytes acquired the phenotype of immature monocyte derived DC (Mo-DC) with similar yields to normal blood Mo-DC generation. Addition of TNF-alpha or LPS induced both normal and CMML Mo-DC to express prominent dendritic processes, the CMRF44+ and CD83+ antigens and high levels of HLA-DR, CD80 and CD86. Treatment either with TNF-alpha or LPS increased the allostimulatory activity of normal Mo-DC, but had little effect on the allostimulatory activity of CMML Mo-DC, perhaps reflecting the underlying neoplastic changes in monocyte precursors. We conclude that the blood DC numbers are relatively unaffected in CMML, suggesting discrete regulation of monocyte and DC production.

Expression of NK cell receptors on decidual T cells in human pregnancy.

PubMed

Tilburgs, Tamara; van der Mast, Barbara J; Nagtzaam, Nicole M A; Roelen, Dave L; Scherjon, Sicco A; Claas, Frans H J

2009-06-01

Specific receptors enable NK cells to discriminate between cells with normal expression of MHC class I and cells that have low or absent expression of MHC class I molecules. In addition to NK cells, these receptors can be expressed on T cell subsets, mainly on CD8+ T cells but also on gammadeltaTCR+ T cells and CD4+ T cells. Although the function of NK cell receptor expression on T cells is not completely understood, various studies have shown that they are involved in down regulation of T cell receptor (TCR)-mediated activation and influence effector functions, like cytotoxicity and cytokine production. The aim of this study was to analyze expression of NK cell receptors on peripheral blood and decidual T cells during human pregnancy using flow cytometry. We demonstrate that a proportion of decidual T cells express HLA-C specific killer immunoglobulin-like receptors (KIRs). Furthermore, a small proportion of decidual T cells express the HLA-E specific CD94-NKG2A inhibitory and CD94-NKG2C activating receptors. Decidual KIR+ and CD94-NKG2+ T cells mainly display a CD3+CD4-CD8- phenotype. However, decidual tissue also contains higher percentages of KIR and CD94-NKG2 expressing CD4+ and CD8+ T cells compared to peripheral blood. So far, the functional capacities of decidual T cells expressing the NK cell receptors are unknown but NK cell receptor expression on decidual T cells may provide an alternative means by which decidual T cells distinguish self (maternal) cells from allogeneic fetal cells, and act to modulate the decidual immune response.

Membrane-bound Dickkopf-1 in Foxp3+ regulatory T cells suppresses T-cell-mediated autoimmune colitis.

PubMed

Chae, Wook-Jin; Park, Jong-Hyun; Henegariu, Octavian; Yilmaz, Saliha; Hao, Liming; Bothwell, Alfred L M

2017-10-01

Induction of tolerance is a key mechanism to maintain or to restore immunological homeostasis. Here we show that Foxp3 + regulatory T (Treg) cells use Dickkopf-1 (DKK-1) to regulate T-cell-mediated tolerance in the T-cell-mediated autoimmune colitis model. Treg cells from DKK-1 hypomorphic doubleridge mice failed to control CD4 + T-cell proliferation, resulting in CD4 T-cell-mediated autoimmune colitis. Thymus-derived Treg cells showed a robust expression of DKK-1 but not in naive or effector CD4 T cells. DKK-1 expression in Foxp3 + Treg cells was further increased upon T-cell receptor stimulation in vitro and in vivo. Interestingly, Foxp3 + Treg cells expressed DKK-1 in the cell membrane and the functional inhibition of DKK-1 using DKK-1 monoclonal antibody abrogated the suppressor function of Foxp3 + Treg cells. DKK-1 expression was dependent on de novo protein synthesis and regulated by the mitogen-activated protein kinase pathway but not by the canonical Wnt pathway. Taken together, our results highlight membrane-bound DKK-1 as a novel Treg-derived mediator to maintain immunological tolerance in T-cell-mediated autoimmune colitis. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd.

γδ T Cells Shape Pre-Immune Peripheral B Cell Populations

PubMed Central

Huang, Yafei; Getahun, Andrew; Heiser, Ryan A.; Detanico, Thiago O.; Aviszus, Katja; Kirchenbaum, Greg A.; Casper, Tamara L.; Huang, Chunjian; Aydintug, M. Kemal; Carding, Simon R.; Ikuta, Koichi; Huang, Hua; Wysocki, Lawrence J.; Cambier, John C.; O’Brien, Rebecca L.; Born, Willi K.

2015-01-01

We previously reported that selective ablation of certain γδ T cell subsets rather than removal of all γδ T cells, strongly affects serum antibody levels in non-immunized mice. This type of manipulation also changed T cells including residual γδ T cells, revealing some interdependence of γδ T cell populations. For example, in mice lacking Vγ4+ and Vγ6+ γδ T cells (B6.TCR-Vγ4−/−/6−/−), we observed expanded Vγ1+ cells, which changed in composition and activation and produced more IL-4 upon stimulation in vitro, increased IL-4 production by αβ T cells as well as spontaneous germinal center formation in the spleen, elevated serum Ig and autoantibodies. We therefore examined B cell populations in this and other γδ-deficient mouse strains. Whereas immature bone marrow B cells remained largely unchanged, peripheral B cells underwent several changes. Specifically, transitional and mature B cells in the spleen of B6.TCR-Vγ4−/−/6−/− mice and other peripheral B cell populations were diminished, most of all splenic marginal zone (MZ) B cells. However, relative frequencies and absolute numbers of antibody-producing cells, and serum levels of antibodies, IL-4 and BAFF, were increased. Cell transfers confirmed that these changes are directly dependent on the altered γδ T cells in this strain, and their enhanced potential of producing IL-4. Further evidence suggests the possibility of direct interactions between γδ T cells and B cells in the splenic MZ. Together, these data demonstrate the capability of γδ T cells of modulating size and productivity of pre-immune peripheral B cell populations. PMID:26582947

Effects of MERTK Inhibitors UNC569 and UNC1062 on the Growth of Acute Myeloid Leukaemia Cells.

PubMed

Koda, Yuki; Itoh, Mai; Tohda, Shuji

2018-01-01

MER proto-oncogene tyrosine kinase (MERTK) is a receptor tyrosine kinase that affects cancer cell proliferation. This study evaluated the effects of the synthetic MERTK inhibitors UNC569 and UNC1062 on in vitro growth of acute myeloid leukaemia (AML) cells. Four AML cell lines expressing MERTK were treated with UNC569 and UNC1062 and analyzed for cell proliferation, immunoblotting, and gene expression. The effects of MERTK knockdown were also evaluated. Treatment with the inhibitors suppressed cell growth and induced apoptosis in all cell lines. OCI/AML5 and TMD7 cells, in which MERTK was constitutively phosphorylated by autocrine mechanisms, were highly susceptible to these inhibitors. The treatment reduced the phosphorylation of MERTK and its down-stream signalling molecules, v-akt murine thymoma viral oncogene homolog 1 (AKT) and extracellular signal-regulated kinase (ERK). Similar effects were observed after MERTK knockdown. The inhibitors and the knockdown caused similar changes in mRNA expression. These MERTK inhibitors are potential molecular-targeted drugs for treating AML expressing constitutively phosphorylated MERTK. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Haematopoietic transplants combining a single unrelated cord blood unit and mobilized haematopoietic stem cells from an adult HLA-mismatched third party donor. Comparable results to transplants from HLA-identical related donors in adults with acute leukaemia and myelodysplastic syndromes.

PubMed

Sebrango, Ana; Vicuña, Isabel; de Laiglesia, Almudena; Millán, Isabel; Bautista, Guiomar; Martín-Donaire, Trinidad; Regidor, Carmen; Cabrera, Rafael; Fernandez, Manuel N

2010-06-01

We describe results of the strategy, developed by our group, of co-infusion of mobilized haematopoietic stem cells as a support for single-unit unrelated cord blood transplant (dual CB/TPD-MHSC transplants) for treatment of haematological malignancies in adults, and a comparative analysis of results obtained using this strategy and transplants performed with mobilized haematopoietic stem cells from related HLA-identical donors (RTD) for treatment of adults with acute leukaemia and myelodysplastic syndromes. Our data show that the dual CB/TPD-MHSC transplant strategy results in periods of post-transplant neutropenia, final rates of full donor chimerism and transplant-related mortality rates comparable to those of the RTD. Final survival outcomes are comparable in adults transplanted because of acute leukaemia, with different incidences of the complications that most influence these: a higher incidence of infections related to late recovery of protective immunity dependent on T cell functions, and a lower incidence of serious acute graft-versus-host disease and relapses. Recent advances in cord blood transplant techniques allow allogeneic haematopoietic stem cell transplantation (HSCT) to be a viable option for almost every patient who may benefit from this therapeutic approach. Development of innovative strategies to improve the post-transplant recovery of T cells function is currently the main challenge to further improving the possibilities of unrelated cord blood transplantation. Copyright © 2010 Elsevier Ltd. All rights reserved.

CD95 co-stimulation blocks activation of naive T cells by inhibiting T cell receptor signaling

PubMed Central

Lindquist, Jonathan A.; Arhel, Nathalie; Felder, Edward; Karl, Sabine; Haas, Tobias L.; Fulda, Simone; Walczak, Henning; Kirchhoff, Frank; Debatin, Klaus-Michael

2009-01-01

CD95 is a multifunctional receptor that induces cell death or proliferation depending on the signal, cell type, and cellular context. Here, we describe a thus far unknown function of CD95 as a silencer of T cell activation. Naive human T cells triggered by antigen-presenting cells expressing a membrane-bound form of CD95 ligand (CD95L) or stimulated by anti-CD3 and -CD28 antibodies in the presence of recombinant CD95L had reduced activation and proliferation, whereas preactivated, CD95-sensitive T cells underwent apoptosis. Triggering of CD95 during T cell priming interfered with proximal T cell receptor signaling by inhibiting the recruitment of ζ-chain–associated protein of 70 kD, phospholipase-γ, and protein kinase C-θ into lipid rafts, thereby preventing their mutual tyrosine protein phosphorylation. Subsequently, Ca2+ mobilization and nuclear translocation of transcription factors NFAT, AP1, and NF-κB were strongly reduced, leading to impaired cytokine secretion. CD95-mediated inhibition of proliferation in naive T cells could not be reverted by the addition of exogenous interleukin-2 and T cells primed by CD95 co-stimulation remained partially unresponsive upon secondary T cell stimulation. HIV infection induced CD95L expression in primary human antigeen-presenting cells, and thereby suppressed T cell activation, suggesting that CD95/CD95L-mediated silencing of T cell activation represents a novel mechanism of immune evasion. PMID:19487421

Special regulatory T-cell review: T-cell dependent suppression revisited.

PubMed

Basten, Antony; Fazekas de St Groth, Barbara

2008-01-01

The concept of T-cell dependent regulation of immune responses has been a central tenet of immunological thinking since the delineation of the two cell system in the 1960s. Indeed T-cell dependent suppression was discovered before MHC restriction. When reviewing the data from the original wave of suppression, it is intriguing to reflect not just on the decline and fall of suppressor T cells in the 1980s, but on their equally dramatic return to respectability over the past decade. Hopefully their resurgence will be supported by solid mechanistic data that will underpin their central place in our current and future understanding of the immune system. Cannon to right of them, Cannon to left of them, Cannon in front of them Volley'd and thunder'd Storm'd at with shot and shell, Boldly they rode and well, Into the jaws of Death, Into the mouth of Hell, Rode the six hundred (suppressionists). (Adapted from The Charge of the Light Brigade, Alfred, Lord Tennyson)

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.

Curtailed T-cell activation curbs effector differentiation and generates CD8+ T cells with a naturally-occurring memory stem cell phenotype.

PubMed

Zanon, Veronica; Pilipow, Karolina; Scamardella, Eloise; De Paoli, Federica; De Simone, Gabriele; Price, David A; Martinez Usatorre, Amaia; Romero, Pedro; Mavilio, Domenico; Roberto, Alessandra; Lugli, Enrico

2017-09-01

Human T memory stem (T SCM ) cells with superior persistence capacity and effector functions are emerging as important players in the maintenance of long-lived T-cell memory and are thus considered an attractive population to be used in adoptive transfer-based immunotherapy of cancer. However, the molecular signals regulating their generation remain poorly defined. Here we show that curtailed T-cell receptor stimulation curbs human effector CD8 + T-cell differentiation and allows the generation of CD45RO - CD45RA + CCR7 + CD27 + CD95 + -phenotype cells from highly purified naïve T-cell precursors, resembling naturally-occurring human T SCM . These cells proliferate extensively in vitro and in vivo, express low amounts of effector-associated genes and transcription factors and undergo considerable self-renewal in response to IL-15 while retaining effector differentiation potential. Such a phenotype is associated with a lower number of mitochondria compared to highly-activated effector T cells committed to terminal differentiation. These results shed light on the molecular signals that are required to generate long-lived memory T cells with potential application in adoptive cell transfer immunotherapy. © 2017 The Authors. European Journal of Immunology published by WILEY-VCH Verlag GmbH & Co.KGaA, Weinheim.

Driving CAR T-cells forward.

PubMed

Jackson, Hollie J; Rafiq, Sarwish; Brentjens, Renier J

2016-06-01

The engineered expression of chimeric antigen receptors (CARs) on the surface of T cells enables the redirection of T-cell specificity. Early clinical trials using CAR T cells for the treatment of patients with cancer showed modest results, but the impressive outcomes of several trials of CD19-targeted CAR T cells in the treatment of patients with B-cell malignancies have generated an increased enthusiasm for this approach. Important lessons have been derived from clinical trials of CD19-specific CAR T cells, and ongoing clinical trials are testing CAR designs directed at novel targets involved in haematological and solid malignancies. In this Review, we discuss these trials and present strategies that can increase the antitumour efficacy and safety of CAR T-cell therapy. Given the fast-moving nature of this field, we only discuss studies with direct translational application currently or soon-to-be tested in the clinical setting.

Adenosine regulates CD8 T-cell priming by inhibition of membrane-proximal T-cell receptor signalling

PubMed Central

Linnemann, Carsten; Schildberg, Frank A; Schurich, Anna; Diehl, Linda; Hegenbarth, Silke I; Endl, Elmar; Lacher, Svenja; Müller, Christa E; Frey, Jürgen; Simeoni, Luca; Schraven, Burkhart; Stabenow, Dirk; Knolle, Percy A

2009-01-01

Adenosine is a well-described anti-inflammatory modulator of immune responses within peripheral tissues. Extracellular adenosine accumulates in inflamed and damaged tissues and inhibits the effector functions of various immune cell populations, including CD8 T cells. However, it remains unclear whether extracellular adenosine also regulates the initial activation of naïve CD8 T cells by professional and semi-professional antigen-presenting cells, which determines their differentiation into effector or tolerant CD8 T cells, respectively. We show that adenosine inhibited the initial activation of murine naïve CD8 T cells after αCD3/CD28-mediated stimulation. Adenosine caused inhibition of activation, cytokine production, metabolic activity, proliferation and ultimately effector differentiation of naïve CD8 T cells. Remarkably, adenosine interfered efficiently with CD8 T-cell priming by professional antigen-presenting cells (dendritic cells) and semi-professional antigen-presenting cells (liver sinusoidal endothelial cells). Further analysis of the underlying mechanisms demonstrated that adenosine prevented rapid tyrosine phosphorylation of the key kinase ZAP-70 as well as Akt and ERK1/2 in naïve αCD3/CD28-stimulated CD8 cells. Consequently, αCD3/CD28-induced calcium-influx into CD8 cells was reduced by exposure to adenosine. Our results support the notion that extracellular adenosine controls membrane-proximal T-cell receptor signalling and thereby also differentiation of naïve CD8 T cells. These data raise the possibility that extracellular adenosine has a physiological role in the regulation of CD8 T-cell priming and differentiation in peripheral organs. PMID:19740334

Adenosine regulates CD8 T-cell priming by inhibition of membrane-proximal T-cell receptor signalling.

PubMed

Linnemann, Carsten; Schildberg, Frank A; Schurich, Anna; Diehl, Linda; Hegenbarth, Silke I; Endl, Elmar; Lacher, Svenja; Müller, Christa E; Frey, Jürgen; Simeoni, Luca; Schraven, Burkhart; Stabenow, Dirk; Knolle, Percy A

2009-09-01

Adenosine is a well-described anti-inflammatory modulator of immune responses within peripheral tissues. Extracellular adenosine accumulates in inflamed and damaged tissues and inhibits the effector functions of various immune cell populations, including CD8 T cells. However, it remains unclear whether extracellular adenosine also regulates the initial activation of naïve CD8 T cells by professional and semi-professional antigen-presenting cells, which determines their differentiation into effector or tolerant CD8 T cells, respectively. We show that adenosine inhibited the initial activation of murine naïve CD8 T cells after alphaCD3/CD28-mediated stimulation. Adenosine caused inhibition of activation, cytokine production, metabolic activity, proliferation and ultimately effector differentiation of naïve CD8 T cells. Remarkably, adenosine interfered efficiently with CD8 T-cell priming by professional antigen-presenting cells (dendritic cells) and semi-professional antigen-presenting cells (liver sinusoidal endothelial cells). Further analysis of the underlying mechanisms demonstrated that adenosine prevented rapid tyrosine phosphorylation of the key kinase ZAP-70 as well as Akt and ERK1/2 in naïve alphaCD3/CD28-stimulated CD8 cells. Consequently, alphaCD3/CD28-induced calcium-influx into CD8 cells was reduced by exposure to adenosine. Our results support the notion that extracellular adenosine controls membrane-proximal T-cell receptor signalling and thereby also differentiation of naïve CD8 T cells. These data raise the possibility that extracellular adenosine has a physiological role in the regulation of CD8 T-cell priming and differentiation in peripheral organs.

Effect of lipoxygenase metabolites of arachidonic acid on proliferation of human T cells and T cell subsets.

PubMed

Gualde, N; Atluru, D; Goodwin, J S

1985-02-01

The lipoxygenase products LTB4 and 15 HPETE have been reported to stimulate T suppressor cell function and also to inhibit [3H]thymidine incorporation into mitogen-stimulated T cells. This present report documents that although these compounds do indeed inhibit [3H]thymidine incorporation into unfractionated T cells, they significantly enhance [3H]thymidine incorporation into T cell preparation enriched for cells bearing the cytotoxic suppressor cell phenotype identified by the OKT8 monoclonal antibody. The mitogen response of T cells enriched for OKT4+ helper-inducer cells is inhibited in manner similar to the response of unfractionated T cells. Thus, LTB4 and 15 HPETE stimulate both the function and the proliferation of the cytotoxic-suppressor T cell subset.

The Complexity of Targeting PI3K-Akt-mTOR Signalling in Human Acute Myeloid Leukaemia: The Importance of Leukemic Cell Heterogeneity, Neighbouring Mesenchymal Stem Cells and Immunocompetent Cells.

PubMed

Brenner, Annette K; Andersson Tvedt, Tor Henrik; Bruserud, Øystein

2016-11-11

Therapeutic targeting of PI3K-Akt-mTOR is considered a possible strategy in human acute myeloid leukaemia (AML); the most important rationale being the proapoptotic and antiproliferative effects of direct PI3K/mTOR inhibition observed in experimental studies of human AML cells. However, AML is a heterogeneous disease and these effects caused by direct pathway inhibition in the leukemic cells are observed only for a subset of patients. Furthermore, the final effect of PI3K-Akt-mTOR inhibition is modulated by indirect effects, i.e., treatment effects on AML-supporting non-leukemic bone marrow cells. In this article we focus on the effects of this treatment on mesenchymal stem cells (MSCs) and monocytes/macrophages; both these cell types are parts of the haematopoietic stem cell niches in the bone marrow. MSCs have unique membrane molecule and constitutive cytokine release profiles, and mediate their support through bidirectional crosstalk involving both cell-cell contact and the local cytokine network. It is not known how various forms of PI3K-Akt-mTOR targeting alter the molecular mechanisms of this crosstalk. The effect on monocytes/macrophages is also difficult to predict and depends on the targeted molecule. Thus, further development of PI3K-Akt-mTOR targeting into a clinical strategy requires detailed molecular studies in well-characterized experimental models combined with careful clinical studies, to identify patient subsets that are likely to respond to this treatment.

IL-23 Activated γδ T Cells Affect Th17 Cells and Regulatory T Cells by Secreting IL-21 in Children with Primary Nephrotic Syndrome.

PubMed

Zhang, L; Yan, J; Yang, B; Zhang, G; Wang, M; Dong, S; Liu, W; Yang, H; Li, Q

2018-01-01

This study (1) analysed the percentage of γδ T cells, γδ T cell subsets, Th17 cells and regulatory T cells (Treg cells) and (2) determined the role of IL-23 in primary nephrotic syndrome (PNS) patients with active disease and in remission. Eighty-four patients with PNS and 51 healthy age-matched controls were included in this study. The percentage of γδ T cells, γδ T cell subsets, Th17 cells and Treg cells in peripheral blood mononuclear cells (PBMCs) were analysed by fluorescence-activated cell sorting. PMBCs from PNS patients with active disease were cultured in the presence of IL-23, IL-23 and an IL-23 antagonist, or IL23 and an anti-IL-21 monoclonal antibody (mAb). The percentage of γδ T cells, IL-23R + γδ T cells and IL-17 + γδ T cells were significantly increased in PNS patients with active disease. There was a positive correlation between the percentage of γδ T cells, IL-23R + γδ T cells, IL-17 + γδ T cells and the Th17/Treg ratio. IL-23 increased the percentage of γδ T cells and Th17 cells and decreased the percentage of Treg cells in PBMCs isolated from PNS patients with active disease. Anti-IL-21 mAb reduced the percentage of γδ T cells and Th17 cells, but increased the percentage of Treg cells. γδ T cells, IL-17 + γδ T cells and IL-23R + γδ T cells may be involved in the pathogenesis of paediatric PNS by modulating the balance of Th17/Treg cells. γδ T cells may cause an imbalance in Th17/Treg cells by secreting IL-21 in the presence of IL-23. © 2017 The Foundation for the Scandinavian Journal of Immunology.

Distinct T helper cell dependence of memory B-cell proliferation versus plasma cell differentiation.

PubMed

Zabel, Franziska; Fettelschoss, Antonia; Vogel, Monique; Johansen, Pål; Kündig, Thomas M; Bachmann, Martin F

2017-03-01

Several memory B-cell subclasses with distinct functions have been described, of which the most effective is the class-switched (CS) memory B-cell population. We have previously shown, using virus-like particles (VLPs), that the proliferative potential of these CS memory B cells is limited and they fail to re-enter germinal centres (GCs). However, VLP-specific memory B cells quickly differentiated into secondary plasma cells (PCs) with the virtue of elevated antibody production compared with primary PCs. Whereas the induction of VLP + memory B cells was strongly dependent on T helper cells, we were wondering whether re-stimulation of VLP + memory B cells and their differentiation into secondary PCs would also require T helper cells. Global absence of T helper cells led to strongly impaired memory B cell proliferation and PC differentiation. In contrast, lack of interleukin-21 receptor-dependent follicular T helper cells or CD40 ligand signalling strongly affected proliferation of memory B cells, but differentiation into mature secondary PCs exhibiting increased antibody production was essentially normal. This contrasts with primary B-cell responses, where a strong dependence on CD40 ligand but limited importance of interleukin-21 receptor was seen. Hence, T helper cell dependence differs between primary and secondary B-cell responses as well as between memory B-cell proliferation and PC differentiation. © 2016 John Wiley & Sons Ltd.

Urokinase receptor and CXCR4 are regulated by common microRNAs in leukaemia cells

PubMed Central

Alfano, Daniela; Gorrasi, Anna; Li Santi, Anna; Ricci, Patrizia; Montuori, Nunzia; Selleri, Carmine; Ragno, Pia

2015-01-01

The urokinase-type plasminogen activator (uPA) receptor (uPAR) focuses uPA proteolytic activity on the cell membrane, promoting localized degradation of extracellular matrix (ECM), and binds vitronectin (VN), mediating cell adhesion to the ECM. uPAR-bound uPA and VN induce proteolysis-independent intracellular signalling, regulating cell adhesion, migration, survival and proliferation. uPAR cross-talks with CXCR4, the receptor for the stroma-derived factor 1 chemokine. CXCR4 is crucial in the trafficking of hematopoietic stem cells from/to the bone marrow, which involves also uPAR. Both uPAR and CXCR4 are expressed in acute myeloid leukaemia (AML), with a lower expression in undifferentiated and myeloid subsets, and higher expression in myelomonocytic and promyelocytic subsets. We hypothesized a microRNA (miR)-mediated co-regulation of uPAR and CXCR4 expression, which could allow their cross-talk at the cell surface. We identified three miRs, miR-146a, miR-335 and miR-622, regulating the expression of both uPAR and CXCR4 in AML cell lines. Indeed, these miRs directly target the 3′untranslated region of both uPAR- and CXCR4-mRNAs; accordingly, uPAR/CXCR4 expression is reduced by their overexpression in AML cells and increased by their specific inhibitors. Overexpression of all three miRs impairs migration, invasion and proliferation of myelomonocytic cells. Interestingly, we observed an inverse relationship between uPAR/CXCR4 expression and miR-146a and miR-335 levels in AML blasts, suggesting their possible role in the regulation of uPAR/CXCR4 expression also in vivo. PMID:26082201

T cell-recruiting triplebody 19-3-19 mediates serial lysis of malignant B-lymphoid cells by a single T cell

PubMed Central

Roskopf, Claudia C.; Schiller, Christian B.; Braciak, Todd A.; Kobold, Sebastian; Schubert, Ingo A.; Fey, Georg H.; Hopfner, Karl-Peter; Oduncu, Fuat S.

2014-01-01

Triplebody 19-3-19, an antibody-derived protein, carries three single chain fragment variable domains in tandem in a single polypeptide chain. 19-3-19 binds CD19-bearing lymphoid cells via its two distal domains and primary T cells via its CD3-targeting central domain in an antigen-specific manner. Here, malignant B-lymphoid cell lines and primary cells from patients with B cell malignancies were used as targets in cytotoxicity tests with pre-stimulated allogeneic T cells as effectors. 19-3-19 mediated up to 95% specific lysis of CD19-positive tumor cells and, at picomolar EC50 doses, had similar cytolytic potency as the clinically successful agent BlinatumomabTM. 19-3-19 activated resting T cells from healthy unrelated donors and mediated specific lysis of both autologous and allogeneic CD19-positive cells. 19-3-19 led to the elimination of 70% of CD19-positive target cells even with resting T cells as effectors at an effector-to-target cell ratio of 1 : 10. The molecule is therefore capable of mediating serial lysis of target cells by a single T cell. These results highlight that central domains capable of engaging different immune effectors can be incorporated into the triplebody format to provide more individualized therapy tailored to a patient’s specific immune status. PMID:25115385

Direct Measurement of T Cell Receptor Affinity and Sequence from Naïve Anti-Viral T Cells

PubMed Central

Zhang, Shuqi; Parker, Patricia; Ma, Keyue; He, Chenfeng; Shi, Qian; Cui, Zhonghao; Williams, Chad; Wendel, Ben S.; Meriwether, Amanda; Salazar, Mary A.; Jiang, Ning

2016-01-01

T cells recognize and kill a myriad of pathogen-infected or cancer cells using a diverse set of T cell receptors (TCR). The affinity of TCR to cognate antigen is of high interest in adoptive T cell transfer immunotherapy and antigen-specific T cell repertoire immune profiling because it is widely known to correlate with downstream T cell responses. Here, we introduce the in situ TCR affinity and sequence test (iTAST) for simultaneous measurement of TCR affinity and sequence from single primary CD8+ T cells in human blood. We demonstrate that the repertoire of primary antigen-specific T cells from pathogen inexperienced individuals has a surprisingly broad affinity range of 1000-fold composed of diverse TCR sequences. Within this range, samples from older individuals contained a reduced frequency of high affinity T cells compared to young individuals, demonstrating an age-related effect of T cell attrition that could cause holes in the repertoire. iTAST should enable the rapid selection of high affinity TCRs ex vivo for adoptive immunotherapy and measurement of T cell response for immune monitoring applications. PMID:27252176

T Cell Receptor Signaling in the Control of Regulatory T Cell Differentiation and Function

PubMed Central

Li, Ming O.; Rudensky, Alexander Y.

2016-01-01

Regulatory T cells (TReg cells), a specialized T cell lineage, have a pivotal function in the control of self-tolerance and inflammatory responses. Recent studies have revealed a discrete mode of TCR signaling that regulates Treg cell differentiation, maintenance and function and that impacts on gene expression, metabolism, cell adhesion and migration of these cells. Here, we discuss the emerging understanding of TCR-guided differentiation of Treg cells in the context of their function in health and disease. PMID:27026074

Driving CAR T-cells forward

PubMed Central

Jackson, Hollie J.; Rafiq, Sarwish; Brentjens, Renier J.

2017-01-01

The engineered expression of chimeric antigen receptors (CARs) on the surface of T cells enables the redirection of T-cell specificity. Early clinical trials using CAR T cells for the treatment of patients with cancer showed modest results, but the impressive outcomes of several trials of CD19-targeted CAR T cells in the treatment of patients with B-cell malignancies have generated an increased enthusiasm for this approach. Important lessons have been derived from clinical trials of CD19-specific CAR T cells, and ongoing clinical trials are testing CAR designs directed at novel targets involved in haematological and solid malignancies. In this Review, we discuss these trials and present strategies that can increase the antitumour efficacy and safety of CAR T-cell therapy. Given the fast-moving nature of this field, we only discuss studies with direct translational application currently or soon-to-be tested in the clinical setting. PMID:27000958

Dynamics of human T-cell lymphotropic virus I (HTLV-I) infection of CD4+ T-cells.

PubMed

Katri, Patricia; Ruan, Shigui

2004-11-01

Stilianakis and Seydel (Bull. Math. Biol., 1999) proposed an ODE model that describes the T-cell dynamics of human T-cell lymphotropic virus I (HTLV-I) infection and the development of adult T-cell leukemia (ATL). Their model consists of four components: uninfected healthy CD4+ T-cells, latently infected CD4+ T-cells, actively infected CD4+ T-cells, and ATL cells. Mathematical analysis that completely determines the global dynamics of this model has been done by Wang et al. (Math. Biosci., 2002). In this note, we first modify the parameters of the model to distinguish between contact and infectivity rates. Then we introduce a discrete time delay to the model to describe the time between emission of contagious particles by active CD4+ T-cells and infection of pure cells. Using the results in Culshaw and Ruan (Math. Biosci., 2000) in the analysis of time delay with respect to cell-free viral spread of HIV, we study the effect of time delay on the stability of the endemically infected equilibrium. Numerical simulations are presented to illustrate the results.

γδ T cells producing interleukin-17A regulate adipose regulatory T cell homeostasis and thermogenesis.

PubMed

Kohlgruber, Ayano C; Gal-Oz, Shani T; LaMarche, Nelson M; Shimazaki, Moto; Duquette, Danielle; Nguyen, Hung N; Mina, Amir I; Paras, Tyler; Tavakkoli, Ali; von Andrian, Ulrich; Banks, Alexander S; Shay, Tal; Brenner, Michael B; Lynch, Lydia

2018-05-01

γδ T cells are situated at barrier sites and guard the body from infection and damage. However, little is known about their roles outside of host defense in nonbarrier tissues. Here, we characterize a highly enriched tissue-resident population of γδ T cells in adipose tissue that regulate age-dependent regulatory T cell (T reg ) expansion and control core body temperature in response to environmental fluctuations. Mechanistically, innate PLZF + γδ T cells produced tumor necrosis factor and interleukin (IL) 17 A and determined PDGFRα + and Pdpn + stromal-cell production of IL-33 in adipose tissue. Mice lacking γδ T cells or IL-17A exhibited decreases in both ST2 + T reg cells and IL-33 abundance in visceral adipose tissue. Remarkably, these mice also lacked the ability to regulate core body temperature at thermoneutrality and after cold challenge. Together, these findings uncover important physiological roles for resident γδ T cells in adipose tissue immune homeostasis and body-temperature control.

Red blood cells as modulators of T cell growth and survival.

PubMed

Arosa, Fernando A; Pereira, Carlos F; Fonseca, Ana M

2004-01-01

T cell homeostasis is largely controlled by a balance between cell death and survival and anomalies in either process account for a number of diseases linked to excessive or faulty T cell growth. Yet, the influence that cells outside the immunological system have on these processes has only recently received attention. Accumulated evidence indicate that homeostasis of the CD4+ and CD8+ T cell pools is highly dynamic and regulated by signals delivered by cells and molecules present in the different internal microenvironments. The major function of red blood cells (RBC) is generally considered to be oxygen and carbon dioxide transport. In recent years, however, RBC have been implicated in the regulation of basic physiological processes, from vascular contraction and platelet aggregation to T cell growth and survival. Regulation of T cell survival by RBC may influence the response of selected subsets of T cells to internal or external stimuli and may help explaining the immunomodulatory activities of red blood cells. By interfering in the balance between death and survival RBC become potential tools that can be manipulated to improve or reverse pathological situations characterized by anomalies in the control of T cell growth.

New Strategies in Engineering T-cell Receptor Gene-Modified T cells to More Effectively Target Malignancies.

PubMed

Schmitt, Thomas M; Stromnes, Ingunn M; Chapuis, Aude G; Greenberg, Philip D

2015-12-01

The immune system, T cells in particular, have the ability to target and destroy malignant cells. However, antitumor immune responses induced from the endogenous T-cell repertoire are often insufficient for the eradication of established tumors, as illustrated by the failure of cancer vaccination strategies or checkpoint blockade for most tumors. Genetic modification of T cells to express a defined T-cell receptor (TCR) can provide the means to rapidly generate large numbers of tumor-reactive T cells capable of targeting tumor cells in vivo. However, cell-intrinsic factors as well as immunosuppressive factors in the tumor microenvironment can limit the function of such gene-modified T cells. New strategies currently being developed are refining and enhancing this approach, resulting in cellular therapies that more effectively target tumors and that are less susceptible to tumor immune evasion. ©2015 American Association for Cancer Research.

Conventional CD4+ T cells present bacterial antigens to induce cytotoxic and memory CD8+ T cell responses.

PubMed

Cruz-Adalia, Aránzazu; Ramirez-Santiago, Guillermo; Osuna-Pérez, Jesús; Torres-Torresano, Mónica; Zorita, Virgina; Martínez-Riaño, Ana; Boccasavia, Viola; Borroto, Aldo; Martínez Del Hoyo, Gloria; González-Granado, José María; Alarcón, Balbino; Sánchez-Madrid, Francisco; Veiga, Esteban

2017-11-17

Bacterial phagocytosis and antigen cross-presentation to activate CD8 + T cells are principal functions of professional antigen presenting cells. However, conventional CD4 + T cells also capture and kill bacteria from infected dendritic cells in a process termed transphagocytosis (also known as transinfection). Here, we show that transphagocytic T cells present bacterial antigens to naive CD8 + T cells, which proliferate and become cytotoxic in response. CD4 + T-cell-mediated antigen presentation also occurs in vivo in the course of infection, and induces the generation of central memory CD8 + T cells with low PD-1 expression. Moreover, transphagocytic CD4 + T cells induce protective anti-tumour immune responses by priming CD8 + T cells, highlighting the potential of CD4 + T cells as a tool for cancer immunotherapy.

Acute undifferentiated leukaemia in a dog.

PubMed

Miglio, A; Antognoni, M T; Miniscalco, B; Caivano, D; Lepri, E; Birettoni, F; Mangili, V

2014-12-01

Acute undifferentiated leukaemia (AUL) is considered a separate entity in the context of acute leukaemias. AUL is extremely rare in both humans and dogs, has a rapid clinical course and does not respond to treatment. It is characterised by the presence of blast cells within the bone marrow and/or peripheral blood at levels ≥ 20% and even up to 100% of all nucleated cells. Blast cells are unable to be differentiated on morphological, cytochemical and phenotypic criteria into myeloid or lymphoid lineages because of their immaturity and/or atypia. An 8-year-old German Shepherd dog was referred for depression, asthenia, mild anaemia, thrombocytopenia and marked leucocytosis. Abdominal ultrasound showed hepatomegaly, splenomegaly, bilateral nephromegaly and enlargement of mesenteric lymph nodes. Echocardiography revealed biventricular hypertrophy with abnormal tissue density of the myocardium. Blood and bone marrow smears were composed of 95% unclassifiable and/or atypical blast cells and signs of dysplasia of the erythroid and thrombocytic/megakaryocytic lineages were present. Blast cells were negative for all cytochemical stains used and flow cytometry of peripheral blood revealed 85% of total leucocytes consisting of small-to-medium-sized cells, negative for all lymphoid and myeloid markers except CD45 and CD34. After necropsy, cytology and histology revealed that blast cells had diffusely infiltrated all tissues examined. Both erythroid and megakaryocytic extramedullary haemopoiesis was also detected in the spleen, lymph nodes and liver. All immunohistochemical stains used were negative. On the basis of all the results, a diagnosis of acute leukaemia involving a very primitive haematopoietic precursor was made. © 2014 Australian Veterinary Association.

Rapid reconstitution of CMV-specific T-cells after stem-cell transplantation.

PubMed

Widmann, Thomas; Sester, Urban; Schmidt, Tina; Gärtner, Barbara C; Schubert, Jörg; Pfreundschuh, Michael; Sester, Martina

2018-04-13

As reconstitution of virus-specific T-cells is critical to control cytomegalovirus (CMV)-viremia following stem-cell transplantation (SCT), we characterized the dynamics in CMV-specific T-cell reconstitution after SCT. Cytomegalovirus-specific T-cells from 51 SCT-recipients were prospectively quantified and phenotypically characterised by intracellular cytokine-staining after specific stimulation and HLA class-I-specific pentamers using flow cytometry. Cytomegalovirus-specific CD4 T-cells reconstituted after a median of 2.3 (IQR, 2.0-3.0) weeks following autografting, and 4.0 (IQR, 3.0-5.6) weeks after allografting, with CMV-specific T-cells originating from donors and/or recipients. The time for reconstitution of CMV-specific CD4 and CD8 T-cells did not differ (P = .58). Factors delaying the time to initial reconstitution of CMV-specific CD4 T-cells included a negative recipient serostatus (P = .016) and CMV-viremia (P = .026). Percentages of CMV-specific CD4 T-cells significantly increased over time and reached a plateau after 90 days (P = .043). Relative CMV-specific CD4 T-cell levels remained higher in long-term transplant recipients compared with those in controls (P < .0001). However, due to persisting lymphopenia, absolute numbers of CMV-specific T-cells were similar as in controls. Cytomegalovirus-specific T-cells rapidly reconstitute after SCT and their percentages remain high in the long term. In the face of persistent lymphopenia, this results in similar absolute numbers of CMV-specific T-cells as in controls to ensure sufficient pathogen control. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Accumulation of cytolytic CD8{sup +} T cells in B16-melanoma and proliferation of mature T cells in TIS21-knockout mice after T cell receptor stimulation

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

Ryu, Min Sook; Woo, Min-Yeong; Department of Biomedical Sciences, The Graduate School, Ajou University

2014-10-01

In vivo and in vitro effects of TIS21 gene on the mature T cell activation and antitumor activities were explored by employing MO5 melanoma orthograft and splenocytes isolated from the TIS21-knockout (KO) mice. Proliferation and survival of mature T cells were significantly increased in the KO than the wild type (WT) cells, indicating that TIS21 inhibits the rate of mature T cell proliferation and its survival. In MO5 melanoma orthograft model, the KO mice recruited much more CD8{sup +} T cells into the tumors at around day 14 after tumor cell injection along with reduced tumor volumes compared with themore » WT. The increased frequency of granzyme B{sup +} CD8{sup +} T cells in splenocytes of the KO mice compared with the WT may account for antitumor-immunity of TIS21 gene in the melanoma orthograft. In contrast, reduced frequencies of CD107a{sup +} CD8{sup +} T cells in the splenocytes of KO mice may affect the loss of CD8{sup +} T cell infiltration in the orthograft at around day 19. These results indicate that TIS21 exhibits antiproliferative and proapoptotic effects in mature T cells, and differentially affects the frequencies of granzyme B{sup +} CD8{sup +} T-cells and CD107a{sup +} CD8{sup +} T-cells, thus transiently regulating in vivo anti-tumor immunity. - Highlights: • Constitutive expression of TIS21 in splenocytes and upregulation by TCR stimulation. • Proliferation of mature T-cells in spleen of TIS21KO mice after TCR stimulation. • Inhibition of cell death in mature T-cells of TIS21KO mice compared with the wild type. • Inhibition of melanoma growth in TIS21KO mice and CD8{sup +} T cell infiltration in tumor. • Reduction of CD 107{sup +}CD8{sup +} T cells, but increased granzyme B{sup +} CD8{sup +} T cells in TIS21KO mice.« less

Monocyte:T cell interaction regulates human T cell activation through a CD28/CD46 crosstalk

PubMed Central

Charron, Lauren; Doctrinal, Axelle; Choileain, Siobhan Ni; Astier, Anne L.

2015-01-01

T cell activation requires engagement of the T cell receptor and of at least one costimulatory molecule. The key role of CD28 in inducing T cell activation has been reported several decades ago and the molecular mechanisms involved well described. The complement regulator CD46 also acts as a costimulatory molecule for T cells but, in contrast to CD28, has the ability to drive T cell differentiation from producing some IFNγ to secreting some potent anti-inflammatory IL-10, acquiring a so-called Type I regulatory phenotype (Tr1). Proteolytic cleavage of CD46 occurs upon costimulation and is important for T cell activation and IL-10 production. The observation that CD46 cleavage was reduced when PBMC were costimulated compared to purified naive T cells led us to hypothesize that interactions between different cell types within the PBMC were able to modulate the CD46 pathway. We show that CD46 downregulation is also reduced when CD4+ T cells are co-cultured with autologous monocytes. Indeed, monocyte:T cell co-cultures impaired CD46–mediated T cell differentiation and coactivation, by reducing downregulation of surface CD46, lowering induction of the early activation marker CD69, as well as reducing the levels of IL-10 secretion. Blocking of CD86 could partly restore CD69 expression and cytokine secretion, demonstrating that the CD28-CD86 pathway regulates CD46 activation. Direct concomitant ligation of CD28 and CD46 on CD4+ T cells also modulated CD46 expression and regulated cytokine production. These data identify a crosstalk between two main costimulatory pathways and provide novel insights into the regulation of human T cell activation. PMID:25787182

Prolymphocytic leukaemia: surface morphology in 21 cases as seen by scanning electron microscopy and comparison with B-type CLL and CLL in 'prolymphocytoid' transformation.

PubMed

Polliack, A; Leizerowitz, R; Berrebi, A; Gamliel, H; Galili, N; Gurfel, D; Catovsky, D

1984-08-01

The surface architecture of leukaemic cells obtained from 21 cases of proven prolymphocytic leukaemia (PLL) and eight cases of chronic lymphocytic leukaemia (CLL) with 'prolymphocytoid' transformation (PL-CLL) was compared with the cell surface morphology of leukaemic cells obtained from 46 cases of B-type CLL, using the scanning electron microscope (SEM). All cases were defined by cytochemistry, immunological markers and transmission electron microscopy prior to SEM examination. B-CLL cells showed the well-recognized spectrum of surface architecture described in earlier studies. The majority of cells had moderate numbers of short microvilli, although in a minority, cells with relatively smooth surfaces predominated. In seven of the eight cases of PL-CLL, cells were villous in nature and in this respect similar to CLL cells; however, more cells with dense microvilli were seen. The prolymphocytic cells were recognized by their larger size and in 18 of the 19 cases of B-derived PLL, villous cells predominated. Two cases of T-derived PLL showed variable cell surface morphology ranging from smooth to moderately villous. It appears that B-PLL cells are most frequently villous and display more surface microvilli than B-CLL cells. B-prolymphocytes display the surface features regarded as characteristic for neoplastic B-cells as seen in patients with B-type lymphoma and leukaemia.

SOX12: a novel potential target for acute myeloid leukaemia.

PubMed

Wan, Haixia; Cai, Jiayi; Chen, Fangyuan; Zhu, Jianyi; Zhong, Jihua; Zhong, Hua

2017-02-01

The role of SRY-related high-mobility-group box (SOX) 12 in leukaemia progression and haematopoiesis remains elusive. This study aimed to examine the expression and function of SOX12 in acute myeloid leukaemia (AML) using human myeloid leukaemia samples and the acute myeloid cell line THP1. Mononuclear cells were isolated from the bone marrow of AML patients and healthy donors. SOX12 expression in haematopoietic cells was evaluated by reverse transcription polymerase chain reaction (RT-PCR). SOX12 short hairpin RNAs (shRNAs) were transduced into THP1 cells, and gene knockdown was confirmed by quantitative RT-PCR and Western blot analysis. SOX12 was preferentially expressed in CD34 + cells in AML patients. The THP1 cells transduced with SOX12 shRNAs exhibited significantly reduced SOX12 expression and cell proliferation. SOX12 knockdown had no effect on apoptosis, but it induced cell cycle arrest at G1 phase and reduced the number of colonies. The transduced THP1 and primary AML cells were reconstituted in non-obese diabetic-severe combined immunodeficient (NOD/SCID) mice, and their numbers were significantly reduced 6-12 weeks after transplantation. The mRNA and protein levels of β-catenin were significantly diminished following SOX12 knockdown, accompanied by a decrease in TCF/Wnt activity. SOX12 may be involved in leukaemia progression by regulating the expression of β-catenin and then interfering with TCF/Wnt pathway, which may be a target for AML. © 2016 John Wiley & Sons Ltd.

Use of internal control T-cell populations in the flow cytometric evaluation for T-cell neoplasms.

PubMed

Hunt, Alicia M; Shallenberger, Wendy; Ten Eyck, Stephen P; Craig, Fiona E

2016-09-01

Flow cytometry is an important tool for identification of neoplastic T-cells, but immunophenotypic abnormalities are often subtle and must be distinguished from nonneoplastic subsets. Use of internal control (IC) T-cells in the evaluation for T-cell neoplasms was explored, both as a quality measure and as a reference for evaluating abnormal antigen expression. All peripheral blood specimens (3-month period), or those containing abnormal T-cells (29-month period), stained with CD45 V500, CD2 V450, CD3 PE-Cy7, CD7 PE, CD4 Per-CP-Cy5.5, CD8 APC-H7, CD56 APC, CD16&57 FITC, were evaluated. IC T-cells were identified (DIVA, BD Biosciences) and median fluorescence intensity (MFI) recorded. Selected files were merged and reference templates generated (Infinicyt, Cytognos). IC T-cells were present in all specimens, including those with abnormal T-cells, but subsets were less well-represented. IC T-cell CD3 MFI differed between instruments (p = 0.0007) and subsets (p < 0.001), but not specimen categories, and served as a longitudinal process control. Merged files highlighted small unusual IC-T subsets: CD2+(dim) (0.25% total), CD2- (0.03% total). An IC reference template highlighted neoplastic T-cells, but was limited by staining variability (IC CD3 MFI reference samples different from test (p = 0.003)). IC T-cells present in the majority of specimens can serve as positive and longitudinal process controls. Use of IC T-cells as an internal reference is limited by variable representation of subsets. Analysis of merged IC T-cells from previously analyzed patient samples can alert the interpreter to less-well-recognized non-neoplastic subsets. However, application of a merged file IC reference template was limited by staining variability. © 2016 Clinical Cytometry Society. © 2016 International Clinical Cytometry Society.

B cells regulate thymic CD8+T cell differentiation in lupus-prone mice.

PubMed

Xing, Chen; Zhu, Gaizhi; Xiao, He; Fang, Ying; Liu, Xiaoling; Han, Gencheng; Chen, Guojiang; Hou, Chunmei; Shen, Beifen; Li, Yan; Ma, Ning; Wang, Renxi

2017-10-27

Previous studies have shown that under normal physiological conditions thymic B cells play a critical function in T cell negative selection. We tested the effect of thymic B cells on thymic T-cell differentiation in autoimmune diseases including systemic lupus erythematosus (SLE). We found that thymic B cells and CD8 - CD4 + and CD4 - CD8 + T cells increased, whereas CD4 + CD8 + T cells decreased in lupus-prone mice. Once B cells were reduced, the change was reversed. Furthermore, we found that B cells blocked thymic immature single positive (ISP) CD4 - CD8 + CD3 lo/- RORγt - T cells progression into CD4 + CD8 + T cells. Interestingly, we found a novel population of thymic immature T cells (CD4 - CD8 + CD3 lo RORγt + ) that were induced into mature CD4 - CD8 + CD3 + RORγt + T cells by B cells in lupus-prone mice. Importantly, we found that IgG, produced by thymic B cells, played a critical role in the differentiation of thymic CD8 + ISP and mature RORγt + CD8 + T cells in lupus-prone mice. In conclusion, B cells blocked the differentiation from thymic CD8 + ISP and induced the differentiation of a novel immature CD4 - CD8 + CD3 lo RORγt + T cells into mature RORγt + CD8 + T cells by secreting IgG antibody in lupus-prone mice.

CD8+CD28- T cells: certainties and uncertainties of a prevalent human T-cell subset.

PubMed

Arosa, Fernando A

2002-02-01

Human peripheral blood CD8+ T cells comprise cells that are in different states of differentiation and under the control of complex homeostatic processes. In a number of situations ranging from chronic inflammatory conditions and infectious diseases to ageing, immunodeficiency, iron overload and heavy alcohol intake, major phenotypic changes, usually associated with an increase in CD8+ T cells lacking CD28 expression, take place. CD8+CD28- T cells are characterized by a low proliferative capacity to conventional stimulation in vitro and by morphological and functional features of activated/memory T cells. Although the nature of the signals that give origin to this T-cell subset is uncertain, growing evidence argues for the existence of an interplay between epithelial cells, molecules with the MHC-class I fold and CD8+ T cells. The possibility that the generation of CD8+CD28- T cells is the combination of TCR/CD3zeta- and regulatory factor-mediated signals as a result of the sensing of modifications of the internal environment is discussed.

Magnetic Field-Induced T Cell Receptor Clustering by Nanoparticles Enhances T Cell Activation and Stimulates Antitumor Activity

PubMed Central

2015-01-01

Iron–dextran nanoparticles functionalized with T cell activating proteins have been used to study T cell receptor (TCR) signaling. However, nanoparticle triggering of membrane receptors is poorly understood and may be sensitive to physiologically regulated changes in TCR clustering that occur after T cell activation. Nano-aAPC bound 2-fold more TCR on activated T cells, which have clustered TCR, than on naive T cells, resulting in a lower threshold for activation. To enhance T cell activation, a magnetic field was used to drive aggregation of paramagnetic nano-aAPC, resulting in a doubling of TCR cluster size and increased T cell expansion in vitro and after adoptive transfer in vivo. T cells activated by nano-aAPC in a magnetic field inhibited growth of B16 melanoma, showing that this novel approach, using magnetic field-enhanced nano-aAPC stimulation, can generate large numbers of activated antigen-specific T cells and has clinically relevant applications for adoptive immunotherapy. PMID:24564881

T-cell/histiocyte-rich large B-cell lymphoma of stomach.

PubMed

Barut, Figen; Kandemir, Nilufer Onak; Gun, Banu Dogan; Ozdamar, Sukru Oguz

2016-07-01

T-cell/histiocyte-rich large B-cell lymphoma is an unusually encountered lymphoid neoplasm of stomach with aggressive course, and is an uncommon morphologic variant of diffuse large B-cell lymphoma. An ulcerated mass, 7x5x1 cm in size was observed within the gastrectomy specimen of a 76-year-old female patient. In cross sections, besides mature lymphoid cells displaying T-cell phenotype, a neoplastic formation composed of large, pleomorphic atypical lymphoid cells with, prominent nucleoli, vesicular nuclei and abundant eosinophilic cytoplasm displaying B-cell phenotype were observed. Meanwhile, histiocyte-like mononuclear cells and Reed-Sternberg-like multinuclear cells expressing CD68 and Mac387 were also observed. The diagnosis of the case was T cell/histiocyte-rich large B-cell lymphoma. This rarely encountered neoplasm should be kept in mind in the differential diagnosis of primary gastric lymphomas.

CD8+ T-cell immunosurveillance constrains lymphoid pre-metastatic myeloid cell accumulation

PubMed Central

Li, Wenzhao; Deng, Jiehui; Herrmann, Andreas; Priceman, Saul J.; Liang, Wei; Shen, Shudan; Pal, Sumanta K.; Hoon, Dave S.B.; Yu, Hua

2014-01-01

Increasing evidence suggests that pre-metastatic niches, consisting mainly of myeloid cells, provide microenvironment critical for cancer cell recruitment and survival to facilitate metastasis. While CD8+ T cells exert immunosurveillance in primary human tumors, whether they can exert similar effects on myeloid cells in the pre-metastatic environment is unknown. Here, we show that CD8+ T cells are capable of constraining pre-metastatic myeloid cell accumulation by inducing myeloid cell apoptosis in C57BL/6 mice. Antigen-specific CD8+ T-cell cytotoxicity against myeloid cells in pre-metastatic lymph nodes is compromised by Stat3. We demonstrate here that Stat3 ablation in myeloid cells leads to CD8+ T-cell activation and increased levels of IFN-γ and granzyme B in the pre-metastatic environment. Furthermore, Stat3 negatively regulates soluble antigen cross-presentation by myeloid cells to CD8+ T cells in the pre-metastatic niche. Importantly, in tumor-free lymph nodes of melanoma patients, infiltration of activated CD8+ T cells inversely correlates with STAT3 activity, which is associated with a decrease in number of myeloid cells. Our study suggested a novel role for CD8+ T cells in constraining myeloid cell activity through direct killing in the pre-metastatic environment, and the therapeutic potential by targeting Stat3 in myeloid cells to improve CD8+ T-cell immunosurveillance against metastasis. PMID:25310972

Contribution of herpesvirus specific CD8 T cells to anti-viral T cell response in humans.

PubMed

Sandalova, Elena; Laccabue, Diletta; Boni, Carolina; Tan, Anthony T; Fink, Katja; Ooi, Eng Eong; Chua, Robert; Shafaeddin Schreve, Bahar; Ferrari, Carlo; Bertoletti, Antonio

2010-08-19

Herpesviruses infect most humans. Their infections can be associated with pathological conditions and significant changes in T cell repertoire but evidences of symbiotic effects of herpesvirus latency have never been demonstrated. We tested the hypothesis that HCMV and EBV-specific CD8 T cells contribute to the heterologous anti-viral immune response. Volume of activated/proliferating virus-specific and total CD8 T cells was evaluated in 50 patients with acute viral infections: 20 with HBV, 12 with Dengue, 12 with Influenza, 3 with Adenovirus infection and 3 with fevers of unknown etiology. Virus-specific (EBV, HCMV, Influenza) pentamer+ and total CD8 T cells were analyzed for activation (CD38/HLA-DR), proliferation (Ki-67/Bcl-2(low)) and cytokine production. We observed that all acute viral infections trigger an expansion of activated/proliferating CD8 T cells, which differs in size depending on the infection but is invariably inflated by CD8 T cells specific for persistent herpesviruses (HCMV/EBV). CD8 T cells specific for other non-related non persistent viral infection (i.e. Influenza) were not activated. IL-15, which is produced during acute viral infections, is the likely contributing mechanism driving the selective activation of herpesvirus specific CD8 T cells. In addition we were able to show that herpesvirus specific CD8 T cells displayed an increased ability to produce the anti-viral cytokine interferon-gamma during the acute phase of heterologous viral infection. Taken together, these data demonstrated that activated herpesvirus specific CD8 T cells inflate the activated/proliferating CD8 T cells population present during acute viral infections in human and can contribute to the heterologous anti-viral T cell response.

Role of T cells in the B-cell response: glutaraldehyde-fixed T-helper hybridoma cells synergize with the lymphokine IL-4 to induce B-cell activation and proliferation.