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

PubMed Central

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

2009-01-01

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

Impaired Upregulation of the Costimulatory Molecules, CD27 and CD28, on CD4+ T Cells from HIV Patients Receiving ART Is Associated with Poor Proliferative Responses.

PubMed

Tanaskovic, Sara; Price, Patricia; French, Martyn A; Fernandez, Sonia

2017-02-01

HIV patients beginning antiretroviral therapy (ART) with advanced immunodeficiency often retain low CD4 + T cell counts despite virological control. We examined proliferative responses and upregulation of costimulatory molecules, following anti-CD3 stimulation, in HIV patients with persistent CD4 + T cell deficiency on ART. Aviremic HIV patients with nadir CD4 + T cell counts <100 cells/μL and who had received ART for a median time of 7 (range 1-11) years were categorized into those achieving low (<350 cells/μL; n = 13) or normal (>500 cells/μL; n = 20) CD4 + T cell counts. Ten healthy controls were also recruited. CD4 + T cell proliferation (Ki67) and upregulation of costimulatory molecules (CD27 and CD28) after anti-CD3 stimulation were assessed by flow cytometry. Results were related to proportions of CD4 + T cells expressing markers of T cell senescence (CD57), activation (HLA-DR), and apoptotic potential (Fas). Expression of CD27 and/or CD28 on uncultured CD4 + T cells was similar in patients with normal CD4 + T cell counts and healthy controls, but lower in patients with low CD4 + T cell counts. Proportions of CD4 + T cells expressing CD27 and/or CD28 correlated inversely with CD4 + T cell expression of CD57, HLA-DR, and Fas. After anti-CD3 stimulation, induction of CD27 hi CD28 hi expression was independent of CD4 + T cell counts, but lower in HIV patients than in healthy controls. Induction of CD27 hi CD28 hi expression correlated with induction of Ki67 expression in total, naïve, and CD31 + naïve CD4 + T cells from patients. In HIV patients responding to ART, impaired induction of CD27 and CD28 on CD4 + T cells after stimulation with anti-CD3 is associated with poor proliferative responses as well as greater CD4 + T cell activation and immunosenescence.

[Clinical characteristic and treatment of cytomegalovirus retinitis in 80 patients with acquired immunodeficiency syndrome].

PubMed

Yang, Yaling; Jiang, Rui; He, Taiwen; Lu, Hongzhou; Zhang, Renfang; Shen, Yinzhong; Zheng, Yufang; Liu, Li; Wang, Wenji

2014-03-01

To investigate the clinical characteristics of cytomegalovirus retinitis (CMVR) in acquired immunodeficiency syndrome (AIDS) patients. Retrospective case-series study. The clinical and laboratory data of 80 AIDS patients (118 eyes) with findings of CMVR were collected from Shanghai Public Health Clinical Center from December 2006 to December 2011. The relationship between CMVR and cellular immunity, the high risk factor, clinical characteristics, treatment and prognosis of CMVR were analyzed in this study. χ(2) test was used to check the incidence of CMVR in different CD4(+) T lymphocyte count groups. There was 80 AIDS patients (118 eyes) totally, 71 males and 9 females. Their age was from 18 to 60 years old, which mean value was (38 ± 10) years old. The incidence in the group of CD4(+) T lymphocyte count over 100 cells/µl was lower than the two groups of CD4(+) T lymphocyte count less than 100 cells/µl (χ(2) = 15.567, 32.469; P = 0.00,0.00). CD4(+) T lymphocyte count was always ranged from 0 to 141 cells/µl in CMVR patients. It was less than 50 cells/µl in 81.3% cases. In 10.0% AIDS patients, CMVR was the first manifestation. In 25% AIDS patients(26 eyes), lesions in retina was found by routine eye examination. In 54.2% patients, the best corrected visual acuity was less than 0.3. Retinal necrosis was involvement near the posterior pole in 62.5% CMVR patients. The visual acuity of 51 eyes was improved after treatment within 94.1% cases which were treated within 3 months. However, BCVA of 35 eyes decreased or with less change within 42.9% cases which were treated after symptoms appeared 3 months. The anti-CMV treatment included induction and maintenance of ganciclovir or foscarnet stopped when the CD4(+)T lymphocyte count was more than 150 cells/µl in 3 continuous months. 86.9% eyes were cured clinically. Retinal detachment, immune reconstitution uveitis and complicated cataract was found in 13.1%, 12.1% and 20.5% cases respectively. Optic atrophy occurred in 6 eyes. The visual acuity of 28.9% eyes was 0.05 or less, 71.3% of that caused by retinal detachment, cataract and optic atrophy. CD4(+) T lymphocyte count reduction is the risk factor for CMVR. HAART and anti-CMV therapy will cure the CMVR clinically.Routine eye examinations should be performed in all AIDS patients to get early diagnosis of CMVR or other opportunistic infections to avoid vision loss, especially in those CD4(+) T lymphocyte count lower than 100 cells/µl.

Visualizing High-Efficiency HIV Transfer | Center for Cancer Research

Cancer.gov

The Human Immunodeficiency Virus (HIV), the causative agent of Acquired Immunodeficiency Syndrome (AIDS), infects and eventually kills CD4 receptor-expressing T cells, which are critical for proper immune system function. The gp120 protein on the surface of HIV particles is known to bind CD4 and a co-receptor, either CCR5 or CXCR4, leading to fusion of the virus and T cell membranes and infection of the cell. The most efficient means of viral infection occurs when an uninfected T cell interacts with a dendritic cell (DC) that has previously come in contact with HIV. Antigen presenting cells, such as DCs, normally circulate throughout the body binding or engulfing foreign material and presenting it to T cells to initiate an immune response. HIV takes advantage of this close cell-cell association to propagate, so knowing the cells’ spatial arrangement during viral transmission could elucidate novel modes of treatment.

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.

Effect of Cytomegalovirus (CMV) and Ageing on T-Bet and Eomes Expression on T-Cell Subsets.

PubMed

Hassouneh, Fakhri; Lopez-Sejas, Nelson; Campos, Carmen; Sanchez-Correa, Beatriz; Tarazona, Raquel; Pera, Alejandra; Solana, Rafael

2017-06-29

The differential impact of ageing and cytomegalovirus (CMV) latent infection on human T-cell subsets remains to some extent controversial. The purpose of this study was to analyse the expression of the transcription factors T-bet and Eomes and CD57 on CD4+, CD4 hi CD8 lo and CD8+ T-cell subsets in healthy individuals, stratified by age and CMV serostatus. The percentage of CD4+ T-cells expressing T-bet or Eomes was very low, in particular in CD4+ T-cells from young CMV-seronegative individuals, and were higher in CMV-seropositive older individuals, in both CD57- and CD57+ CD4+ T-cells. The study of the minor peripheral blood double-positive CD4 hi CD8 lo T-cells showed that the percentage of these T-cells expressing both Eomes and T-bet was higher compared to CD4+ T-cells. The percentage of CD4 hi CD8 lo T-cells expressing T-bet was also associated with CMV seropositivity and the coexpression of Eomes, T-bet and CD57 on CD4 hi CD8 lo T-cells was only observed in CMV-seropositive donors, supporting the hypothesis that these cells are mature effector memory cells. The percentage of T-cells expressing Eomes and T-bet was higher in CD8+ T-cells than in CD4+ T-cells. The percentages of CD8+ T-cells expressing Eomes and T-bet increased with age in CMV-seronegative and -seropositive individuals and the percentages of CD57- CD8+ and CD57+ CD8+ T-cells coexpressing both transcription factors were similar in the different groups studied. These results support that CMV chronic infection and/or ageing are associated to the expansion of highly differentiated CD4+, CD4 hi CD8 lo and CD8+ T-cells that differentially express T-bet and Eomes suggesting that the expression of these transcription factors is essential for the generation and development of an effector-memory and effector T lymphocytes involved in conferring protection against chronic CMV infection.

Burn-injury affects gut-associated lymphoid tissues derived CD4+ T cells.

PubMed

Fazal, Nadeem; Shelip, Alla; Alzahrani, Alhusain J

2013-01-01

After scald burn-injury, the intestinal immune system responds to maintain immune balance. In this regard CD4+T cells in Gut-Associated Lymphoid Tissues (GALT), like mesenteric lymph nodes (MLN) and Peyer's patches (PP) respond to avoid immune suppression following major injury such as burn. Therefore, we hypothesized that the gut CD4+T cells become dysfunctional and turn the immune homeostasis towards depression of CD4+ T cell-mediated adaptive immune responses. In the current study we show down regulation of mucosal CD4+ T cell proliferation, IL-2 production and cell surface marker expression of mucosal CD4+ T cells moving towards suppressive-type. Acute burn-injury lead to up-regulation of regulatory marker (CD25+), down regulation of adhesion (CD62L, CD11a) and homing receptor (CD49d) expression, and up-regulation of negative co-stimulatory (CTLA-4) molecule. Moreover, CD4+CD25+ T cells of intestinal origin showed resistance to spontaneous as well as induced apoptosis that may contribute to suppression of effector CD4+ T cells. Furthermore, gut CD4+CD25+ T cells obtained from burn-injured animals were able to down-regulate naïve CD4+ T cell proliferation following adoptive transfer of burn-injured CD4+CD25+ T cells into sham control animals, without any significant effect on cell surface activation markers. Together, these data demonstrate that the intestinal CD4+ T cells evolve a strategy to promote suppressive CD4+ T cell effector responses, as evidenced by enhanced CD4+CD25+ T cells, up-regulated CTLA-4 expression, reduced IL-2 production, tendency towards diminished apoptosis of suppressive CD4+ T cells, and thus lose their natural ability to regulate immune homeostasis following acute burn-injury and prevent immune paralysis.

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.

CMV induces expansion of highly polyfunctional CD4+ T cell subset coexpressing CD57 and CD154.

PubMed

Pera, Alejandra; Vasudev, Anusha; Tan, Crystal; Kared, Hassen; Solana, Rafael; Larbi, Anis

2017-02-01

CD4 + T cells are essential for human CMV infection control. CMV-specific CD4 + T cells possess antiviral functions and participate in anti-CMV humoral/cellular responses. In the elderly, CMV infection impairs immunity to other viruses and has been traditionally associated with T cell senescence; however, recent results suggest that, in younger people, CMV confers immune protection against other pathogens (heterologous immunity). To shed light on this controversy, we analyzed latent CMV infection effects on the quality of young individuals' immune response, specifically, the presence of polyfunctional T cells through an extensive phenotypic and functional characterization of the CD4 + T cell subset. CD154 expression, degranulation (CD107a), and cytokine production (IFN-γ, TNF-α, and IL-2) as well as T cell phenotype markers (CD57, CD28, and CD27) were analyzed. We demonstrate that CD4 + T cells that coexpress CD57 and CD154, which are exclusively present in CMV-positive individuals, are the most polyfunctional CD4 + subset, whereas CD4 + CD27 + CD28 - T cells associate with lower polyfunctionality. Conversely, the frequency of CD4 + CD28 + T cells correlates with higher polyfunctionality of CD4 + CD57 - T cells from CMV-seronegative individuals and CD4 + CD57 + CD154 + T cells from CMV-seropositive individuals. Thus, polyfunctionality is a property of central memory CD4 + T cells in CMV-seronegative individuals, whereas after CMV infection, polyfunctional T cells become highly differentiated, which allows efficient eradication of infections. We extend previous observations of the impact of CMV on CD8 + T cell functionality to the CD4 + T cell compartment, revealing CD57 as a polyfunctionality marker of T cells which expands after CMV infection. CD57 + T cells have been associated with inflammatory conditions, but their potential role in the response against infectious disease and vaccination should now be investigated. © Society for Leukocyte Biology.

The ThPOK transcription factor differentially affects the development and function of self-specific CD8(+) T cells and regulatory CD4(+) T cells.

PubMed

Twu, Yuh-Ching; Teh, Hung-Sia

2014-03-01

The zinc finger transcription factor ThPOK plays a crucial role in CD4 T-cell development and CD4/CD8 lineage decision. In ThPOK-deficient mice, developing T cells expressing MHC class II-restricted T-cell receptors are redirected into the CD8 T-cell lineage. In this study, we investigated whether the ThPOK transgene affected the development and function of two additional types of T cells, namely self-specific CD8 T cells and CD4(+) FoxP3(+) T regulatory cells. Self-specific CD8 T cells are characterized by high expression of CD44, CD122, Ly6C, 1B11 and proliferation in response to either IL-2 or IL-15. The ThPOK transgene converted these self-specific CD8 T cells into CD4 T cells. The converted CD4(+) T cells are no longer self-reactive, lose the characteristics of self-specific CD8 T cells, acquire the properties of conventional CD4 T cells and survive poorly in peripheral lymphoid organs. By contrast, the ThPOK transgene promoted the development of CD4(+) FoxP3(+) regulatory T cells resulting in an increased recovery of CD4(+) FoxP3(+) regulatory T cells that expressed higher transforming growth factor-β-dependent suppressor activity. These studies indicate that the ThPOK transcription factor differentially affects the development and function of self-specific CD8 T cells and CD4(+) FoxP3(+) regulatory T cells. © 2013 John Wiley & Sons Ltd.

CD4+ T Cell Help Guides Formation of CD103+ Lung-Resident Memory CD8+ T Cells during Influenza Viral Infection

PubMed Central

Laidlaw, Brian J.; Zhang, Nianzhi; Marshall, Heather D.; Staron, Mathew M.; Guan, Tianxia; Hu, Yinghong; Cauley, Linda S.; Craft, Joe; Kaech, Susan M.

2014-01-01

SUMMARY Tissue-resident memory T (Trm) cells provide enhanced protection against infection at mucosal sites. Here we found that CD4+ T cells are important for the formation of functional lung-resident CD8+ T cells after influenza virus infection. In the absence of CD4+ T cells, CD8+ T cells displayed reduced expression of CD103 (Itgae), were mislocalized away from airway epithelia, and demonstrated an impaired ability to recruit CD8+ T cells to the lung air-ways upon heterosubtypic challenge. CD4+ T cell-derived interferon-γ was necessary for generating lung-resident CD103+ CD8+ Trm CD8 T cells. Furthermore, expression of the transcription factor T-bet was increased in “unhelped” lung Trm cells, and a reduction in T-bet rescued CD103 expression in the absence of CD4+ T cell help. Thus, CD4+ T cell-dependent signals are important to limit expression of T-bet and allow for the development of CD103+ CD8+ Trm cells in the lung airways following respiratory infection. PMID:25308332

Segregated Regulatory CD39+ CD4+ T Cell Function: TGF-β-Producing FoxP3− and IL-10-Producing FoxP3+ Cells Are Interdependent for Protection Against Collagen-Induced Arthritis1

PubMed Central

Kochetkova, Irina; Thornburg, Theresa; Callis, Gayle; Pascual, David W.

2011-01-01

Oral immunization with a Salmonella vaccine vector expressing enterotoxigenic E. coli colonization factor antigen I (CFA/I) can protect against collagen-induced arthritis (CIA) by dampening IL-17 and IFN-γ via enhanced IL-4, IL-10, and TGF-β. To identify the responsible regulatory CD4+ T cells making the host refractory to CIA, Salmonella-CFA/I induced CD39+CD4+ T cells with enhanced apyrase activity relative to Salmonella vector-immunized mice. Adoptive transfer of vaccine-induced CD39+CD4+ T cells into CIA mice conferred complete protection, while CD39−CD4+ T cells did not. Subsequent analysis of vaccinated FoxP3-GFP mice revealed the CD39+ T cells were composed of FoxP3-GFP− and FoxP3-GFP+ subpopulations. Although each adoptively transferred Salmonella-CFA/I-induced FoxP3− and FoxP3+CD39+CD4+ T cells could protect against CIA, each subset was not as efficacious as total CD39+CD4+ T cells, suggesting their interdependence for optimal protection. Cytokine analysis revealed FoxP3− CD39+CD4+ T cells produced TGF-β, and FoxP3+CD39+CD4+ T cells produced IL-10, showing a segregation of function. Moreover, donor FoxP3-GFP− CD4+ T cells converted to FoxP3-GFP+ CD39+CD4+ T cells in the recipients, showing plasticity of these regulatory T cells. TGF-β was found to be essential for protection since in vivo TGF-β neutralization reversed activation of cAMP-response element-binding protein (CREB) and reduced the development of CD39+CD4+ T cells. Thus, CD39 apyrase-expressing CD4+ T cells stimulated by Salmonella-CFA/I are composed of TGF-β-producing FoxP3− CD39+CD4+ T cells and support the stimulation of IL-10-producing FoxP3+ CD39+CD4+ T cells. PMID:21967895

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

Most Do, but Some Do Not: CD4+CD25− T Cells, but Not CD4+CD25+ Treg Cells, Are Cytolytic When Redirected by a Chimeric Antigen Receptor (CAR)

PubMed Central

Hombach, Andreas A.; Abken, Hinrich

2017-01-01

Evidences are accumulating that CD4+ T cells can physiologically mediate antigen specific target cell lysis. By circumventing major histocompatibility complex (MHC)-restrictions through an engineered chimeric antigen receptor (CAR), CD4+ T cells lyse defined target cells as efficiently as do CD8+ T cells. However, the cytolytic capacity of redirected CD4+CD25− T cells, in comparison with CD4+CD25+ regulatory T (Treg) cells was so far not thoroughly defined. Treg cells require a strong CD28 signal together with CD3ζ for activation. We consequently used a CAR with combined CD28­CD3ζ signalling for redirecting CD4+CD25− T cells and CD4+CD25+ Treg cells from the same donor. CAR redirected activation of these T cell subsets and induced a distinct cytokine pattern with high IL-10 and a lack of IL-2 release by Treg cells. Despite strong antigen-specific activation, CAR Treg cells produced only weak target cell lysis, whereas CD4+CD25− CAR T cells were potent killers. Cytolysis did not correlate with the target cell sensitivity to Fas/FasL mediated killing; CD4+CD25− T cells upregulated perforin and granzyme B upon CAR activation, whereas Treg cells did less. The different cytolytic capacities of CAR redirected conventional CD4+ cells and Treg cells imply their use for different purposes in cell therapy. PMID:28850063

Regulation and Gene Expression Profiling of NKG2D Positive Human Cytomegalovirus-Primed CD4+ T-Cells

PubMed Central

Jensen, Helle; Folkersen, Lasse; Skov, Søren

2012-01-01

NKG2D is a stimulatory receptor expressed by natural killer (NK) cells, CD8+ T-cells, and γδ T-cells. NKG2D expression is normally absent from CD4+ T-cells, however recently a subset of NKG2D+ CD4+ T-cells has been found, which is specific for human cytomegalovirus (HCMV). This particular subset of HCMV-specific NKG2D+ CD4+ T-cells possesses effector-like functions, thus resembling the subsets of NKG2D+ CD4+ T-cells found in other chronic inflammations. However, the precise mechanism leading to NKG2D expression on HCMV-specific CD4+ T-cells is currently not known. In this study we used genome-wide analysis of individual genes and gene set enrichment analysis (GSEA) to investigate the gene expression profile of NKG2D+ CD4+ T-cells, generated from HCMV-primed CD4+ T-cells. We show that the HCMV-primed NKG2D+ CD4+ T-cells possess a higher differentiated phenotype than the NKG2D– CD4+ T-cells, both at the gene expression profile and cytokine profile. The ability to express NKG2D at the cell surface was primarily determined by the activation or differentiation status of the CD4+ T-cells and not by the antigen presenting cells. We observed a correlation between CD94 and NKG2D expression in the CD4+ T-cells following HCMV stimulation. However, knock-down of CD94 did not affect NKG2D cell surface expression or signaling. In addition, we show that NKG2D is recycled at the cell surface of activated CD4+ T-cells, whereas it is produced de novo in resting CD4+ T-cells. These findings provide novel information about the gene expression profile of HCMV-primed NKG2D+ CD4+ T-cells, as well as the mechanisms regulating NKG2D cell surface expression. PMID:22870231

Regulation and gene expression profiling of NKG2D positive human cytomegalovirus-primed CD4+ T-cells.

PubMed

Jensen, Helle; Folkersen, Lasse; Skov, Søren

2012-01-01

NKG2D is a stimulatory receptor expressed by natural killer (NK) cells, CD8(+) T-cells, and γδ T-cells. NKG2D expression is normally absent from CD4(+) T-cells, however recently a subset of NKG2D(+) CD4(+) T-cells has been found, which is specific for human cytomegalovirus (HCMV). This particular subset of HCMV-specific NKG2D(+) CD4(+) T-cells possesses effector-like functions, thus resembling the subsets of NKG2D(+) CD4(+) T-cells found in other chronic inflammations. However, the precise mechanism leading to NKG2D expression on HCMV-specific CD4(+) T-cells is currently not known. In this study we used genome-wide analysis of individual genes and gene set enrichment analysis (GSEA) to investigate the gene expression profile of NKG2D(+) CD4(+) T-cells, generated from HCMV-primed CD4(+) T-cells. We show that the HCMV-primed NKG2D(+) CD4(+) T-cells possess a higher differentiated phenotype than the NKG2D(-) CD4(+) T-cells, both at the gene expression profile and cytokine profile. The ability to express NKG2D at the cell surface was primarily determined by the activation or differentiation status of the CD4(+) T-cells and not by the antigen presenting cells. We observed a correlation between CD94 and NKG2D expression in the CD4(+) T-cells following HCMV stimulation. However, knock-down of CD94 did not affect NKG2D cell surface expression or signaling. In addition, we show that NKG2D is recycled at the cell surface of activated CD4(+) T-cells, whereas it is produced de novo in resting CD4(+) T-cells. These findings provide novel information about the gene expression profile of HCMV-primed NKG2D(+) CD4(+) T-cells, as well as the mechanisms regulating NKG2D cell surface expression.

Expansion and productive HIV-1 infection of Foxp3 positive CD4 T cells at pleural sites of HIV/TB co-infection

PubMed Central

Hirsch, Christina S; Baseke, Joy; Kafuluma, John Lusiba; Nserko, Mary; Mayanja-Kizza, Harriet; Toossi, Zahra

2016-01-01

Background CD4 T-cells expressing Foxp3 are expanded systemically during active tuberculosis (TB) regardless of HIV-1 co-infection. Foxp3+ CD4 T cells are targets of HIV-1 infection. However, expansion of HIV-1 infected Foxp3+ CD4 T cells at sites of HIV/TB co-infection, and whether they contribute to promotion of HIV-1 viral activity is not known. Methods Pleural fluid mononuclear cells (PFMC) from HIV/TB co-infected patients with pleural TB were characterized by immune-staining and FACS analysis for surface markers CD4, CD127, CCR5, CXCR4, HLA-DR and intracellular expression of Foxp3, HIVp24, IFN-γ and Bcl-2. Whole PFMC and bead separated CD4+CD25+CD127− T cells were assessed for HIV-1 LTR strong stop (SS) DNA by real-time PCR, which represents viral DNA post cell entry and initiation of reverse transcription. Results High numbers of HIV-1 p24 positive Foxp3+ and Foxp3+CD127− CD4 T cells were identified in PFMC from HIV/TB co-infected subjects. CD4+Foxp3+CD127− T cells displayed high expression of the cellular activation marker, HLA-DR. Further, expression of the HIV-1 co-receptors, CCR5 and CXCR4, were higher on CD4+Foxp3+T cells compared to CD4+Foxp3− T cells. Purified CD4+CD25+CD127− T cells isolated from PFMC of HIV/TB co-infected patients, were over 90% CD4+Foxp3+T cells, and exhibited higher HIV-1 SS DNA as compared to whole PFMC, and as compared to CD4+CD25+CD127− T cells from an HIV-infected subject with pleural mesothelioma. HIV-1 p24+ Foxp3+ CD4+T cells from HIV/TB patients higher in Bcl-2 expression as compared to both HIV-1 p24+ Foxp3− CD4 T cells, and Foxp3+ CD4+T cells without HIV-p24 expression. Conclusion Foxp3+ CD4 T cells in PFMC from HIV/TB co-infected subjects are predisposed to productive HIV-1 infection and have survival advantage as compared to Foxp3 negative CD4 T cells. PMID:28124031

Characterization of CD4+ T cell-mediated cytotoxicity in patients with multiple myeloma.

PubMed

Zhang, Xiaole; Gao, Lei; Meng, Kai; Han, Chunting; Li, Qiang; Feng, Zhenjun; Chen, Lei

2018-05-01

Multiple myeloma (MM) is an incurable cancer characterized by the development of malignant plasma cells. The CD8 T cell-mediated cytotoxicity is considered a major player in antitumor immunity, but in MM patients, the CD8 T cells displayed senescence markers and were functionally impaired. To investigate whether cytotoxic CD4 T cells could act as a treatment alternative in MM, we examined the frequency and function of naturally occurring cytotoxic CD4 T cells in MM patients. The cytotoxic CD4 T cells were identified as granzyme-A, granzyme B-, and perforin-expressing CD4 T cells, and their frequencies were significantly upregulated in MM patients when compared with healthy controls. The frequencies of cytotoxic CD4 T cells in MM patients were not associated with the frequencies of cytotoxic CD8 T cells, but were negatively associated with disease severity. Interestingly, the expression levels of inhibitory molecules, including PD-1 and CTLA-4, were significantly lower in cytotoxic CD4 T cells than in cytotoxic CD8 T cells. When co-incubated with autologous CD38 + CD138 + plasma cells, CD4 T cells were capable of eliminating plasma cells with varying degrees of efficacy. In MM patients, the frequency of circulating plasma cells was negatively correlated with the frequency of cytotoxic CD4 T cells. Therefore, CD4 T cell-mediated cytotoxicity existed naturally in MM patients and could potentially act as an option in antitumor therapies. Copyright © 2018 Elsevier Inc. All rights reserved.

Cytotoxic CD4+ T Cells Drive Multiple Sclerosis Progression.

PubMed

Peeters, Liesbet M; Vanheusden, Marjan; Somers, Veerle; Van Wijmeersch, Bart; Stinissen, Piet; Broux, Bieke; Hellings, Niels

2017-01-01

Multiple sclerosis (MS) is the leading cause of chronic neurological disability in young adults. The clinical disease course of MS varies greatly between individuals, with some patients progressing much more rapidly than others, making prognosis almost impossible. We previously discovered that cytotoxic CD4+ T cells (CD4+ CTL), identified by the loss of CD28, are able to migrate to sites of inflammation and that they contribute to tissue damage. Furthermore, in an animal model for MS, we showed that these cells are correlated with inflammation, demyelination, and disability. Therefore, we hypothesize that CD4+ CTL drive progression of MS and have prognostic value. To support this hypothesis, we investigated whether CD4+ CTL are correlated with worse clinical outcome and evaluated the prognostic value of these cells in MS. To this end, the percentage of CD4+CD28null T cells was measured in the blood of 176 patients with relapsing-remitting MS (=baseline). Multimodal evoked potentials (EP) combining information on motoric, visual, and somatosensoric EP, as well as Kurtzke expanded disability status scale (EDSS) were used as outcome measurements at baseline and after 3 and 5 years. The baseline CD4+CD28null T cell percentage is associated with EP ( P  = 0.003, R 2  = 0.28), indicating a link between these cells and disease severity. In addition, the baseline CD4+CD28null T cell percentage has a prognostic value since it is associated with EP after 3 years ( P  = 0.005, R 2  = 0.29) and with EP and EDSS after 5 years ( P  = 0.008, R 2  = 0.42 and P  = 0.003, R 2  = 0.27). To the best of our knowledge, this study provides the first direct link between the presence of CD4+ CTL and MS disease severity, as well as its prognostic value. Therefore, we further elaborate on two important research perspectives: 1° investigating strategies to block or reverse pathways in the formation of these cells resulting in new treatments that slow down MS disease progression, 2° including immunophenotyping in prediction modeling studies to aim for personalized medicine.

Antigen presenting cells (APCs) from thermally injured and/or septic rats modulate CD4+ T cell responses of naive rat.

PubMed

Fazal, Nadeem; Raziuddin, Syed; Khan, Mehdi; Al-Ghoul, Walid M

2006-01-01

Regulation of immune response is marked by complex interactions among the cells that recognize and present antigens. Antigen presenting cells (APCs), the antigen presenting cell component of the innate immune response plays an important role in effector CD4+ T cell response. Thermal injury and/or superimposed sepsis in rats' leads to suppressed CD4+ T cell functions. We investigated modulations of CD4+ T cell function by APCs (purified non-T cells) from thermally injured and/or septic rats. Rats were subjected to 30% total body surface area scald burn or exposed to 37 degrees C water (Sham burn) and sepsis was induced by cecal-ligation and puncture (CLP) method. At day 3 post-injury animals were sacrificed and CD4+ T cells and APCs from mesenteric lymph nodes (MLN) were obtained using magnetic microbead isolation procedure. APCs from injured rats were co-cultured with sham rat MLN CD4+ T cells and proliferative responses (thymidine incorporation), phenotypic changes (Flow cytometry), IL-2 production (ELISA) and CTLA-4 mRNA (RT-PCR) were determined in naive rat CD4+ T cells. The data indicate that APCs from thermally injured and/or septic rats when co-cultured with CD4+ T cells suppressed CD4+ T cell effector functions. This lack of CD4+ T cell activation was accompanied with altered co-stimulatory molecules, i.e., CD28 and/or CTLA-4 (CD152). In conclusion, our studies indicated that defective APCs from thermally injured and/or septic rats modulate CD4+ T cell functions via changes in co-stimulatory molecules expressed on naive CD4+ T cells. This altered APC: CD4+ T cell interaction leads to suppressed CD4+ T cell activation of healthy animals.

Curcumin Inhibits CD4+ T Cell Activation, but Augments CD69 Expression and TGF-β1-Mediated Generation of Regulatory T Cells at Late Phase

PubMed Central

Kim, Girak; Jang, Mi Seon; Son, Young Min; Seo, Min Ji; Ji, Sang Yun; Han, Seung Hyun; Jung, In Duk; Park, Yeong-Min; Jung, Hyun Jung; Yun, Cheol-Heui

2013-01-01

Background Curcumin is a promising candidate for a natural medicinal agent to treat chronic inflammatory diseases. Although CD4+ T cells have been implicated in the pathogenesis of chronic inflammation, whether curcumin directly regulates CD4+ T cells has not been definitively established. Here, we showed curcumin-mediated regulation of CD2/CD3/CD28-initiated CD4+ T cell activation in vitro. Methodology/Principal Findings Primary human CD4+ T cells were stimulated with anti-CD2/CD3/CD28 antibody-coated beads as an in vitro surrogate system for antigen presenting cell-T cell interaction and treated with curcumin. We found that curcumin suppresses CD2/CD3/CD28-initiated CD4+ T cell activation by inhibiting cell proliferation, differentiation and cytokine production. On the other hand, curcumin attenuated the spontaneous decline of CD69 expression and indirectly increased expression of CCR7, L-selectin and Transforming growth factor-β1 (TGF-β1) at the late phase of CD2/CD3/CD28-initiated T cell activation. Curcumin-mediated up-regulation of CD69 at late phase was associated with ERK1/2 signaling. Furthermore, TGF-β1 was involved in curcumin-mediated regulation of T cell activation and late-phase generation of regulatory T cells. Conclusions/Significance Curcumin not merely blocks, but regulates CD2/CD3/CD28-initiated CD4+ T cell activation by augmenting CD69, CCR7, L-selectin and TGF-β1 expression followed by regulatory T cell generation. These results suggest that curcumin could directly reduce T cell-dependent inflammatory stress by modulating CD4+ T cell activation at multiple levels. PMID:23658623

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

PubMed Central

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

2013-01-01

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

Cooperativity of HIV-Specific Cytolytic CD4 T Cells and CD8 T Cells in Control of HIV Viremia

PubMed Central

Johnson, Susan; Eller, Michael; Teigler, Jeffrey E.; Maloveste, Sebastien M.; Schultz, Bruce T.; Soghoian, Damien Z.; Lu, Richard; Oster, Alexander F.; Chenine, Agnès-Laurence; Alter, Galit; Dittmer, Ulf; Marovich, Mary; Robb, Merlin L.; Michael, Nelson L.; Bolton, Diane

2015-01-01

ABSTRACT CD4+ T cells play a pivotal role in the control of chronic viral infections. Recently, nontraditional CD4+ T cell functions beyond helper effects have been described, and a role for cytolytic CD4+ T cells in the control of HIV infection has been suggested. We define here the transcriptional, phenotypic, and functional profiles of HIV-specific cytolytic CD4+ T cells. Fluidigm BioMark and multiparameter flow cytometric analysis of HIV-specific cytolytic CD4+ T cells revealed a distinct transcriptional signature compared to Th1 CD4+ cells but shared similar features with HIV-specific cytolytic CD8+ T cells. Furthermore, HIV-specific cytolytic CD4+ T cells showed comparable killing activity relative to HIV-specific CD8+ T cells and worked cooperatively in the elimination of virally infected cells. Interestingly, we found that cytolytic CD4+ T cells emerge early during acute HIV infection and tightly follow acute viral load trajectory. This emergence was associated to the early viral set point, suggesting an involvement in early control, in spite of CD4 T cell susceptibility to HIV infection. Our data suggest cytolytic CD4+ T cells as an independent subset distinct from Th1 cells that show combined activity with CD8+ T cells in the long-term control of HIV infection. IMPORTANCE The ability of the immune system to control chronic HIV infection is of critical interest to both vaccine design and therapeutic approaches. Much research has focused on the effect of the ability of CD8+ T cells to control the virus, while CD4+ T cells have been overlooked as effectors in HIV control due to the fact that they are preferentially infected. We show here that a subset of HIV-specific CD4+ T cells cooperate in the cytolytic control of HIV replication. Moreover, these cells represent a distinct subset of CD4+ T cells showing significant transcriptional and phenotypic differences compared to HIV-specific Th1 cells but with similarities to CD8+ T cells. These findings are important for our understanding of HIV immunopathology. PMID:25972560

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

PubMed Central

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

2013-01-01

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

Changes in Reactivity In Vitro of CD4+CD25+ and CD4+CD25− T Cell Subsets in Transplant Tolerance

PubMed Central

Hall, Bruce M.; Robinson, Catherine M.; Plain, Karren M.; Verma, Nirupama D.; Tran, Giang T.; Nomura, Masaru; Carter, Nicole; Boyd, Rochelle; Hodgkinson, Suzanne J.

2017-01-01

Transplant tolerance induced in adult animals is mediated by alloantigen-specific CD4+CD25+ T cells, yet in many models, proliferation of CD4+ T cells from hosts tolerant to specific-alloantigen in vitro is not impaired. To identify changes that may diagnose tolerance, changes in the patterns of proliferation of CD4+, CD4+CD25+, and CD4+CD25− T cells from DA rats tolerant to Piebald Virol Glaxo rat strain (PVG) cardiac allografts and from naïve DA rats were examined. Proliferation of CD4+ T cells from both naïve and tolerant hosts was similar to both PVG and Lewis stimulator cells. In mixed lymphocyte culture to PVG, proliferation of naïve CD4+CD25− T cells was greater than naïve CD4+ T cells. In contrast, proliferation of CD4+CD25− T cells from tolerant hosts to specific-donor PVG was not greater than CD4+ T cells, whereas their response to Lewis and self-DA was greater than CD4+ T cells. Paradoxically, CD4+CD25+ T cells from tolerant hosts did not proliferate to PVG, but did to Lewis, whereas naïve CD4+CD25+ T cells proliferate to both PVG and Lewis but not to self-DA. CD4+CD25+ T cells from tolerant, but not naïve hosts, expressed receptors for interferon (IFN)-γ and IL-5 and these cytokines promoted their proliferation to specific-alloantigen PVG but not to Lewis or self-DA. We identified several differences in the patterns of proliferation to specific-donor alloantigen between cells from tolerant and naïve hosts. Most relevant is that CD4+CD25+ T cells from tolerant hosts failed to proliferate or suppress to specific donor in the absence of either IFN-γ or IL-5. The proliferation to third-party and self of each cell population from tolerant and naïve hosts was similar and not affected by IFN-γ or IL-5. Our findings suggest CD4+CD25+ T cells that mediate transplant tolerance depend on IFN−γ or IL-5 from alloactivated Th1 and Th2 cells. PMID:28878770

Low molecular weight fraction secreted by SKOV3 cells expands peripheral CD4+CD25+ regulatory T cells and enhances their suppressive capacity.

PubMed

Li, Xiao; Wan, Xiaoyun; Mao, Yuyan; Lu, Weiguo; Xie, Xing

2010-09-01

The increase of CD4+CD25+ regulatory T cells in patients with ovarian carcinoma has been verified. Here we investigated the effects of supernatant derived from ovarian carcinoma cell SKOV3 on peripheral regulatory T cells. Supernatant from SKOV3 was collected and fractionated into three different molecular weight fractions (MWFs). The proliferation of the CD4+CD25+ regulatory T cells cultured in complete RPMI 1640 medium with the different stimulators was detected. The phenotype (GITR and CTLA-4) of natural and expanded CD4+CD25+ T cells was detected by flow cytometry. Foxp3 mRNA expression of low MWF-expanded CD4+CD25+ T cells was detected by RT-PCR. Those expanded CD4+CD25+ regulatory T cells showed enhanced capacity to suppress CD4+CD25- T proliferation and increased expression of GITR and CTLA-4. In brief, low molecular weight fraction of supernatant secreted by SKOV3 could expand peripheral CD4+CD25+ regulatory T cells and enhance their suppressive function.

A Lower Baseline CD4/CD8 T-Cell Ratio Is Independently Associated with Immunodiscordant Response to Antiretroviral Therapy in HIV-Infected Subjects

PubMed Central

Rosado-Sánchez, I.; Herrero-Fernández, I.; Álvarez-Ríos, A. I.; Genebat, M.; Abad-Carrillo, M. A.; Ruiz-Mateos, E.; Pulido, F.; González-García, J.; Montero, M.; Bernal-Morell, E.; Vidal, F.; Leal, M.

2017-01-01

ABSTRACT We explored if baseline CD4/CD8 T-cell ratio is associated with immunodiscordant response to antiretroviral therapy in HIV-infected subjects. Comparing immunodiscordant and immunoconcordant subjects matched by pretreatment CD4 counts, we observed a lower pretreatment CD4/CD8 T-cell ratio in immunodiscordant subjects. Furthermore, pretreatment CD4/CD8 T-cell ratio, but not CD4 counts, correlated with the main immunological alterations observed in immunodiscordants, including increased regulatory T-cell (Treg) frequency and T-cell turnover-related markers. Then, in a larger cohort, only baseline CD4/CD8 T-cell ratio was independently associated with immunodiscordance, after adjusting by the viral CXCR4-tropic HIV variants. Our results suggest that the CD4/CD8 T-cell ratio could be an accurate biomarker of the subjacent immunological damage triggering immunodiscordance. PMID:28559274

Function and regulation of LAG3 on CD4+CD25- T cells in non-small cell lung cancer.

PubMed

Ma, Qin-Yun; Huang, Da-Yu; Zhang, Hui-Jun; Wang, Shaohua; Chen, Xiao-Feng

2017-11-15

LAG3 is a surface molecule found on a subset of immune cells. The precise function of LAG3 appears to be context-dependent. In this study, we investigated the effect of LAG3 on CD4 + CD25 - T cells from non-small cell lung cancer (NSCLC) patients. We found that in the peripheral blood mononuclear cells of NSCLC patients, LAG3 was significantly increased in CD4 + T cells directly ex vivo and primarily in the CD4 + CD25 - fraction, which was regulated by prolonged TCR stimulation and the presence of IL-27. TCR stimulation also increased CD25 expression, but not Foxp3 expression, in LAG3-expressing CD4 + CD25 - cells Compared to LAG3-nonexpressing CD4 + CD25 - cells, LAG3-expressing CD4 + CD25 - cells presented significantly higher levels of PD1 and TIM3, two inhibitory receptors best described in exhausted CD8 + T effector cells. LAG3-expressing CD4 + CD25 - cells also presented impaired proliferation compared with LAG3-nonexpressing CD4 + CD25 - cells but could be partially rescued by inhibiting both PD1 and TIM3. Interestingly, CD8 + T cells co-incubated with LAG3-expressing CD4 + CD25 - cells at equal cell numbers demonstrated significantly lower proliferation than CD8 + T cells incubated alone. Co-culture with CD8 + T cell and LAG3-expressing CD4 + CD25 - T cell also upregulated soluble IL-10 level in the supernatant, of which the concentration was positively correlated with the number of LAG3-expressing CD4 + CD25 - T cells. In addition, we found that LAG3-expressing CD4 + CD25 - T cells infiltrated the resected tumors and were present at higher frequencies of in metastases than in primary tumors. Taken together, these data suggest that LAG3-expressing CD4 + CD25 - T cells represent another regulatory immune cell type with potential to interfere with anti-tumor immunity. Copyright © 2017 Elsevier Inc. All rights reserved.

HBV-specific CD4+ cytotoxic T cells in hepatocellular carcinoma are less cytolytic toward tumor cells and suppress CD8+ T cell-mediated antitumor immunity.

PubMed

Meng, Fanzhi; Zhen, Shoumei; Song, Bin

2017-08-01

In East Asia and sub-Saharan Africa, chronic infection is the main cause of the development of hepatocellular carcinoma, an aggressive cancer with low survival rate. Cytotoxic T cell-based immunotherapy is a promising treatment strategy. Here, we investigated the possibility of using HBV-specific CD4 + cytotoxic T cells to eliminate tumor cells. The naturally occurring HBV-specific cytotoxic CD4 + and CD8 + T cells were identified by HBV peptide pool stimulation. We found that in HBV-induced hepatocellular carcinoma patients, the HBV-specific cytotoxic CD4 + T cells and cytotoxic CD8 + T cells were present at similar numbers. But compared to the CD8 + cytotoxic T cells, the CD4 + cytotoxic T cells secreted less cytolytic factors granzyme A (GzmA) and granzyme B (GzmB), and were less effective at eliminating tumor cells. In addition, despite being able to secrete cytolytic factors, CD4 + T cells suppressed the cytotoxicity mediated by CD8 + T cells, even when CD4 + CD25 + regulator T cells were absent. Interestingly, we found that interleukin 10 (IL-10)-secreting Tr1 cells were enriched in the cytotoxic CD4 + T cells. Neutralization of IL-10 abrogated the suppression of CD8 + T cells by CD4 + CD25 - T cells. Neither the frequency nor the absolute number of HBV-specific CD4 + cytotoxic T cells were correlated with the clinical outcome of advanced stage hepatocellular carcinoma patients. Together, this study demonstrated that in HBV-related hepatocellular carcinoma, CD4 + T cell-mediated cytotoxicity was present naturally in the host and had the potential to exert antitumor immunity, but its capacity was limited and was associated with immunoregulatory properties. © 2017 APMIS. Published by John Wiley & Sons Ltd.

CRTAM determines the CD4+ cytotoxic T lymphocyte lineage

PubMed Central

Takeuchi, Arata; Badr, Mohamed El Sherif Gadelhaq; Miyauchi, Kosuke; Ishihara, Chitose; Onishi, Reiko; Guo, Zijin; Sasaki, Yoshiteru; Ike, Hiroshi; Takumi, Akiko; Tsuji, Noriko M.; Murakami, Yoshinori; Katakai, Tomoya; Kubo, Masato

2016-01-01

Naive T cells differentiate into various effector T cells, including CD4+ helper T cell subsets and CD8+ cytotoxic T cells (CTL). Although cytotoxic CD4+ T cells (CD4+CTL) also develop from naive T cells, the mechanism of development is elusive. We found that a small fraction of CD4+ T cells that express class I–restricted T cell–associated molecule (CRTAM) upon activation possesses the characteristics of both CD4+ and CD8+ T cells. CRTAM+ CD4+ T cells secrete IFN-γ, express CTL-related genes, such as eomesodermin (Eomes), Granzyme B, and perforin, after cultivation, and exhibit cytotoxic function, suggesting that CRTAM+ T cells are the precursor of CD4+CTL. Indeed, ectopic expression of CRTAM in T cells induced the production of IFN-γ, expression of CTL-related genes, and cytotoxic activity. The induction of CD4+CTL and IFN-γ production requires CRTAM-mediated intracellular signaling. CRTAM+ T cells traffic to mucosal tissues and inflammatory sites and developed into CD4+CTL, which are involved in mediating protection against infection as well as inducing inflammatory response, depending on the circumstances, through IFN-γ secretion and cytotoxic activity. These results reveal that CRTAM is critical to instruct the differentiation of CD4+CTL through the induction of Eomes and CTL-related gene. PMID:26694968

CD4+VEGFR1(HIGH) T cell as a novel Treg subset regulates inflammatory bowel disease in lymphopenic mice.

PubMed

Shin, Jin-Young; Yoon, Il-Hee; Lim, Jong-Hyung; Shin, Jun-Seop; Nam, Hye-Young; Kim, Yong-Hee; Cho, Hyoung-Soo; Hong, So-Hee; Kim, Jung-Sik; Lee, Won-Woo; Park, Chung-Gyu

2015-09-01

Regulatory T cells (Tregs) are a specialized subpopulation of T cells that control the immune response and thereby maintain immune system homeostasis and tolerance to self-antigens. Many subsets of CD4(+) Tregs have been identified, including Foxp3(+), Tr1, Th3, and Foxp3neg iT(R)35 cells. In this study, we identified a new subset of CD4(+)VEGFR1(high) Tregs that have immunosuppressive capacity. CD4(+)VEGFR1high T cells, which constitute approximately 1.0% of CD4(+) T cells, are hyporesponsive to T-cell antigen receptor stimulation. Surface marker and FoxP3 expression analysis revealed that CD4(+)VEGFR1(high) T cells are distinct from known Tregs. CD4(+)VEGFR1(high) T cells suppressed the proliferation of CD4(+)CD25(-) T cell as efficiently as CD4(+)CD25(high) natural Tregs in a contact-independent manner. Furthermore, adoptive transfer of CD4(+)VEGFR1(+) T cells from wild type to RAG-2-deficient C57BL/6 mice inhibited effector T-cell-mediated inflammatory bowel disease. Thus, we report CD4(+) VEGFR1(high) T cells as a novel subset of Tregs that regulate the inflammatory response in the intestinal tract.

Respiratory Syncytial Virus (RSV) Infects CD4+ T Cells: Frequency of Circulating CD4+ RSV+ T Cells as a Marker of Disease Severity in Young Children.

PubMed

Raiden, Silvina; Sananez, Inés; Remes-Lenicov, Federico; Pandolfi, Julieta; Romero, Cecilia; De Lillo, Leonardo; Ceballos, Ana; Geffner, Jorge; Arruvito, Lourdes

2017-04-01

Although human airway epithelial cells are the main target of respiratory syncytial virus (RSV), it also infects immune cells, such as macrophages and B cells. Whether T cells are permissive to RSV infection is unknown. We sought to analyze the permissiveness of CD4+ T cells to RSV infection. CD4+ and CD8+ T cells from cord blood, healthy young children, and adults were challenged by RSV or cocultured with infected HEp-2 cells. Infection, phenotype, and cytokine production by T cells were analyzed by flow cytometry or enzyme-linked immunosorbent assay. Expression of RSV antigens by circulating CD4+ T cells from infected children was analyzed by flow cytometry, and disease severity was defined by standard criteria. CD4+ and CD8+ T cells were productively infected by RSV. Infection decreased interleukin 2 and interferon γ production as well as the expression of CD25 and Ki-67 by activated CD4+ T cells. Respiratory syncytial virus antigens were detected in circulating CD4+ and CD8+ T cells during severe RSV infection of young children. Interestingly, the frequency of CD4+ RSV+ T cells positively correlated with disease severity. Respiratory syncytial virus infects CD4+ and CD8+ T cells and compromises T-cell function. The frequency of circulating CD4+ RSV+ T cells might represent a novel marker of severe infection. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Immune responses induced by T-cell vaccination in patients with rheumatoid arthritis

PubMed Central

Ivanova, Irina; Seledtsova, Galina; Mamaev, Sergey; Shishkov, Alexey; Seledtsov, Viktor

2014-01-01

Patients with rheumatoid arthritis (RA) were treated with a cellular vaccine, which consisted of autologous collagen-reactive T-cells. This study showed that antigen-specific proliferative activity of the peripheral blood mononuclear cells was significantly downregulated after T-cell vaccination in RA patients. T-cell vaccination resulted in a statistically significant decrease in plasma IFNγ levels and a concomitant increase in IL-4 levels in treated patients. Accordingly, following T-cell vaccination the number of IFNγ-producing CD4+ and CD8+ T-cells was decreased by 1.6–1.8-fold, which was paralleled by 1.7-fold increases in IL-4-producing CD4+ T-cells. In addition, the present study showed 5–7-fold increase in the CD8+CD45RO+CD62L– effector memory T-cells and central memory T-cells (both CD4+ CD45RO+CD62L+ T-cells and CD8+CD45RO+CD62L+ T-cells) in RA patients, as compared with healthy individuals. We observed significant reduction in CD4+ and CD8+ central memory T-cells, as well as reduction in CD8+ effector memory T-cells in vaccinated patients in the course of the treatment. We also demonstrated that CD4+CD25+FoxP3+ regulatory T-cell levels were significantly up-regulated in the peripheral blood of RA patients following T-cell vaccination. However, CD4+CD25-FoxP3+ Т-cell levels did not significantly change during the entire T-cell vaccination course. In conclusion, the T-cell immunotherapy regimen used resulted in the clinical improvement, which was achieved in 87% patients. PMID:24633313

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.

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.

Detailed analysis of Epstein–Barr virus-specific CD4+ and CD8+ T cell responses during infectious mononucleosis

PubMed Central

Scherrenburg, J; Piriou, E R W A N; Nanlohy, N M; van Baarle, D

2008-01-01

We studied simultaneously Epstein–Barr virus (EBV)-specific CD4+ and CD8+ T cell responses during and after infectious mononucleosis (IM), using a previously described 12-day stimulation protocol with EBNA1 or BZLF1 peptide pools. Effector function of EBV-specific T cells was determined after restimulation by measuring intracellular interferon-γ production. During IM, BZLF1-specifc CD4+ T cell responses were dominant compared with CD8+ T cell responses. EBNA1-specific CD4+ and CD8+ T cell responses were low and remained similar for 6 months. However, 6 months after IM, BZLF1-specific CD4+ T cell responses had declined, but CD8+ T cell responses had increased. At diagnosis, EBV-specific CD8+ T cells as studied by human leucocyte antigen class I tetramer staining comprised a tetramerbrightCD8bright population consisting mainly of CD27+ memory T cells and a tetramerdimCD8dim population consisting primarily of CD27- effector T cells. The remaining EBV-specific CD8+ T cell population 6 months after the diagnosis of IM consisted mainly of tetramerbrightCD8bright CD27+ T cells, suggesting preferential preservation of memory T cells after contraction of the EBV-specific T cell pool. PMID:18549439

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

PubMed

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

2012-04-09

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

Dynamic Imaging of CD8(+) T cells and dendritic cells during infection with Toxoplasma gondii.

PubMed

John, Beena; Harris, Tajie H; Tait, Elia D; Wilson, Emma H; Gregg, Beth; Ng, Lai Guan; Mrass, Paulus; Roos, David S; Dzierszinski, Florence; Weninger, Wolfgang; Hunter, Christopher A

2009-07-01

To better understand the initiation of CD8(+) T cell responses during infection, the primary response to the intracellular parasite Toxoplasma gondii was characterized using 2-photon microscopy combined with an experimental system that allowed visualization of dendritic cells (DCs) and parasite specific CD8(+) T cells. Infection with T. gondii induced localization of both these populations to the sub-capsular/interfollicular region of the draining lymph node and DCs were required for the expansion of the T cells. Consistent with current models, in the presence of cognate antigen, the average velocity of CD8(+) T cells decreased. Unexpectedly, infection also resulted in modulation of the behavior of non-parasite specific T cells. This TCR-independent process correlated with the re-modeling of the lymph node micro-architecture and changes in expression of CCL21 and CCL3. Infection also resulted in sustained interactions between the DCs and CD8(+) T cells that were visualized only in the presence of cognate antigen and were limited to an early phase in the response. Infected DCs were rare within the lymph node during this time frame; however, DCs presenting the cognate antigen were detected. Together, these data provide novel insights into the earliest interaction between DCs and CD8(+) T cells and suggest that cross presentation by bystander DCs rather than infected DCs is an important route of antigen presentation during toxoplasmosis.

Dynamic Imaging of CD8+ T Cells and Dendritic Cells during Infection with Toxoplasma gondii

PubMed Central

John, Beena; Harris, Tajie H.; Tait, Elia D.; Wilson, Emma H.; Gregg, Beth; Ng, Lai Guan; Mrass, Paulus; Roos, David S.; Dzierszinski, Florence; Weninger, Wolfgang; Hunter, Christopher A.

2009-01-01

To better understand the initiation of CD8+ T cell responses during infection, the primary response to the intracellular parasite Toxoplasma gondii was characterized using 2-photon microscopy combined with an experimental system that allowed visualization of dendritic cells (DCs) and parasite specific CD8+ T cells. Infection with T. gondii induced localization of both these populations to the sub-capsular/interfollicular region of the draining lymph node and DCs were required for the expansion of the T cells. Consistent with current models, in the presence of cognate antigen, the average velocity of CD8+ T cells decreased. Unexpectedly, infection also resulted in modulation of the behavior of non-parasite specific T cells. This TCR-independent process correlated with the re-modeling of the lymph node micro-architecture and changes in expression of CCL21 and CCL3. Infection also resulted in sustained interactions between the DCs and CD8+ T cells that were visualized only in the presence of cognate antigen and were limited to an early phase in the response. Infected DCs were rare within the lymph node during this time frame; however, DCs presenting the cognate antigen were detected. Together, these data provide novel insights into the earliest interaction between DCs and CD8+ T cells and suggest that cross presentation by bystander DCs rather than infected DCs is an important route of antigen presentation during toxoplasmosis. PMID:19578440

Glioblastoma-targeted CD4+ CAR T cells mediate superior antitumor activity.

PubMed

Wang, Dongrui; Aguilar, Brenda; Starr, Renate; Alizadeh, Darya; Brito, Alfonso; Sarkissian, Aniee; Ostberg, Julie R; Forman, Stephen J; Brown, Christine E

2018-05-17

Chimeric antigen receptor-modified (CAR-modified) T cells have shown promising therapeutic effects for hematological malignancies, yet limited and inconsistent efficacy against solid tumors. The refinement of CAR therapy requires an understanding of the optimal characteristics of the cellular products, including the appropriate composition of CD4+ and CD8+ subsets. Here, we investigated the differential antitumor effect of CD4+ and CD8+ CAR T cells targeting glioblastoma-associated (GBM-associated) antigen IL-13 receptor α2 (IL13Rα2). Upon stimulation with IL13Rα2+ GBM cells, the CD8+ CAR T cells exhibited robust short-term effector function but became rapidly exhausted. By comparison, the CD4+ CAR T cells persisted after tumor challenge and sustained their effector potency. Mixing with CD4+ CAR T cells failed to ameliorate the effector dysfunction of CD8+ CAR T cells, while surprisingly, CD4+ CAR T cell effector potency was impaired when coapplied with CD8+ T cells. In orthotopic GBM models, CD4+ outperformed CD8+ CAR T cells, especially for long-term antitumor response. Further, maintenance of the CD4+ subset was positively correlated with the recursive killing ability of CAR T cell products derived from GBM patients. These findings identify CD4+ CAR T cells as a highly potent and clinically important T cell subset for effective CAR therapy.

Glioblastoma-targeted CD4+ CAR T cells mediate superior antitumor activity

PubMed Central

Wang, Dongrui; Starr, Renate; Alizadeh, Darya; Brito, Alfonso; Sarkissian, Aniee; Ostberg, Julie R.; Forman, Stephen J.; Brown, Christine E.

2018-01-01

Chimeric antigen receptor–modified (CAR-modified) T cells have shown promising therapeutic effects for hematological malignancies, yet limited and inconsistent efficacy against solid tumors. The refinement of CAR therapy requires an understanding of the optimal characteristics of the cellular products, including the appropriate composition of CD4+ and CD8+ subsets. Here, we investigated the differential antitumor effect of CD4+ and CD8+ CAR T cells targeting glioblastoma-associated (GBM-associated) antigen IL-13 receptor α2 (IL13Rα2). Upon stimulation with IL13Rα2+ GBM cells, the CD8+ CAR T cells exhibited robust short-term effector function but became rapidly exhausted. By comparison, the CD4+ CAR T cells persisted after tumor challenge and sustained their effector potency. Mixing with CD4+ CAR T cells failed to ameliorate the effector dysfunction of CD8+ CAR T cells, while surprisingly, CD4+ CAR T cell effector potency was impaired when coapplied with CD8+ T cells. In orthotopic GBM models, CD4+ outperformed CD8+ CAR T cells, especially for long-term antitumor response. Further, maintenance of the CD4+ subset was positively correlated with the recursive killing ability of CAR T cell products derived from GBM patients. These findings identify CD4+ CAR T cells as a highly potent and clinically important T cell subset for effective CAR therapy. PMID:29769444

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

PubMed Central

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

2012-01-01

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

CD137 is a Useful Marker for Identifying CD4+ T Cell Responses to Mycobacterium tuberculosis.

PubMed

Yan, Z-H; Zheng, X-F; Yi, L; Wang, J; Wang, X-J; Wei, P-J; Jia, H-Y; Zhou, L-J; Zhao, Y-L; Zhang, H-T

2017-05-01

Upregulation of CD137 on recently activated CD8 + T cells has been used to identify rare viral and tumour antigen-specific T cells from the peripheral blood. We aimed to evaluate the accuracy of CD137 for identifying Mycobacterium tuberculosis (Mtb)-reactive CD4 + T cells in the peripheral blood of infected individuals by flow cytometry and to investigate the characteristics of these CD137 + CD4 + T cells. We initially enrolled 31 active tuberculosis (TB) patients, 31 individuals with latent TB infection (LTBI) and 25 healthy donors. The intracellular CD137 and interferon-γ (IFN-γ) production by CD4 + T cells was simultaneously detected under unstimulated and CFP10-stimulated (culture filtrate protein 10, a Mtb-specific antigen) conditions. In unstimulated CD4 + T cells, we found that the CD137 expression in the TB group was significantly higher than that in the LTBI group. Stimulation with CFP10 largely increased the CD4 + T cell CD137 expression in both the TB and LTBI groups. After CFP10 stimulation, the frequency of CD137 + CD4 + T cells was higher than that of IFN-γ + CD4 + T cells in both the TB and LTBI groups. Most of the CFP10-activated IFN-γ-secreting cells were CD137-positive, but only a small fraction of the CD137-positive cells expressed IFN-γ. An additional 20 patients with TB were enrolled to characterize the CD45RO + CCR7 + , CD45RO + CCR7 - and CD45RO - subsets in the CD137 + CD4 + T cell populations. The Mtb-specific CD137 + CD4 + T cells were mainly identified as having an effector memory phenotype. In conclusion, CD137 is a useful marker that can be used for identifying Mtb-reactive CD4 + T cells by flow cytometry. © 2017 The Foundation for the Scandinavian Journal of Immunology.

Isolation of CD4+CD25+ regulatory T cells for clinical trials.

PubMed

Hoffmann, Petra; Boeld, Tina J; Eder, Ruediger; Albrecht, Julia; Doser, Kristina; Piseshka, Biserka; Dada, Ashraf; Niemand, Claudia; Assenmacher, Mario; Orsó, Evelyn; Andreesen, Reinhard; Holler, Ernst; Edinger, Matthias

2006-03-01

The adoptive transfer of donor CD4+CD25+ regulatory T cells has been shown to protect from lethal graft-versus-host disease after allogeneic bone marrow transplantation in murine disease models. Efficient isolation strategies that comply with good manufacturing practice (GMP) guidelines are prerequisites for the clinical application of human CD4+CD25+ regulatory T cells. Here we describe the isolation of CD4+CD25+ T cells with regulatory function from standard leukapheresis products by using a 2-step magnetic cell-separation protocol performed under GMP conditions. The generated cell products contained on average 49.5% CD4+CD25high T cells that phenotypically and functionally represented natural CD4+CD25+ regulatory T cells and showed a suppressive activity comparable to that of CD4+CD25+ regulatory T-cell preparations purified by non-GMP-approved fluorescence-activated cell sorting.

Transporters for Antiretroviral Drugs in Colorectal CD4+ T Cells and Circulating α4β7 Integrin CD4+ T Cells: Implications for HIV Microbicides.

PubMed

Mukhopadhya, Indrani; Murray, Graeme I; Duncan, Linda; Yuecel, Raif; Shattock, Robin; Kelly, Charles; Iannelli, Francesco; Pozzi, Gianni; El-Omar, Emad M; Hold, Georgina L; Hijazi, Karolin

2016-09-06

CD4+ T lymphocytes in the colorectal mucosa are key in HIV-1 transmission and dissemination. As such they are also the primary target for antiretroviral (ARV)-based rectal microbicides for pre-exposure prophylaxis. Drug transporters expressed in mucosal CD4+ T cells determine ARV distribution across the cell membrane and, most likely, efficacy of microbicides. We describe transporters for antiretroviral drugs in colorectal mucosal CD4+ T lymphocytes and compare gene expression with circulating α4β7+CD4+ T cells, which traffic to the intestine and have been shown to be preferentially infected by HIV-1. Purified total CD4+ T cells were obtained from colorectal tissue and blood samples by magnetic separation. CD4+ T cells expressing α4β7 integrin were isolated by fluorescence-activated cell sorting from peripheral blood mononuclear cells of healthy volunteers. Expressions of 15 efflux and uptake drug transporter genes were quantified using Taqman qPCR assays. Expression of efflux transporters MRP3, MRP5, and BCRP and uptake transporter CNT2 were significantly higher in colorectal CD4+ T cells compared to circulating CD4+ T cells (p = 0.01-0.03). Conversely, circulating α4β7+CD4+ T cells demonstrated significantly higher expression of OATPD compared to colorectal CD4+ T cells (p = 0.001). To the best of our knowledge this is the first report of drug transporter gene expression in colorectal CD4+ and peripheral α4β7+CD4+ T cells. The qualitative and quantitative differences in drug transporter gene expression profiles between α4β7+CD4+ T cells and total mucosal CD4+ T cells may have significant implications for the efficacy of rectally delivered ARV-microbicides. Most notably, we have identified efflux drug transporters that could be targeted by selective inhibitors or beneficial drug-drug interactions to enhance intracellular accumulation of antiretroviral drugs.

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

PubMed

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

2010-08-05

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

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

PubMed Central

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

2010-01-01

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

Mass Cytometry Analysis Reveals the Landscape and Dynamics of CD32a+ CD4+ T Cells From Early HIV Infection to Effective cART.

PubMed

Coindre, Sixtine; Tchitchek, Nicolas; Alaoui, Lamine; Vaslin, Bruno; Bourgeois, Christine; Goujard, Cecile; Avettand-Fenoel, Veronique; Lecuroux, Camille; Bruhns, Pierre; Le Grand, Roger; Beignon, Anne-Sophie; Lambotte, Olivier; Favier, Benoit

2018-01-01

CD32a has been proposed as a specific marker of latently HIV-infected CD4 + T cells. However, CD32a was recently found to be expressed on CD4 + T cells of healthy donors, leading to controversy on the relevance of this marker in HIV persistence. Here, we used mass cytometry to characterize the landscape and variation in the abundance of CD32a + CD4 + T cells during HIV infection. To this end, we analyzed CD32a + CD4 + T cells in primary HIV infection before and after effective combination antiretroviral therapy (cART) and in healthy donors. We found that CD32a + CD4 + T cells include heterogeneous subsets that are differentially affected by HIV infection. Our analysis revealed that naive ( N ), central memory ( CM ), and effector/memory ( Eff/Mem ) CD32a + CD4 + T-cell clusters that co-express LILRA2- and CD64-activating receptors were more abundant in primary HIV infection and cART stages. Conversely, LILRA2 - CD32a + CD4 + T-cell clusters of either the T N , T CM , or T Eff/Mem phenotype were more abundant in healthy individuals. Finally, an activated CD32a + CD4 + T Eff/Mem cell cluster co-expressing LILRA2, CD57, and NKG2C was more abundant in all HIV stages, particularly during primary HIV infection. Overall, our data show that multiple abundance modifications of CD32a + CD4 + T-cell subsets occur in the early phase of HIV infection, and some of which are conserved after effective cART. Our study brings a better comprehension of the relationship between CD32a expression and CD4 + T cells during HIV infection.

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

PubMed

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

2008-06-01

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

Dry eye syndrome: developments and lifitegrast in perspective

PubMed Central

Lollett, Ivonne V; Galor, Anat

2018-01-01

Dry eye (DE) is a chronic ocular condition with high prevalence and morbidity. It has a complex pathophysiology and is multifactorial in nature. Chronic ocular surface inflammation has emerged as a key component of DE that is capable of perpetuating ocular surface damage and leading to symptoms of ocular pain, discomfort, and visual phenomena. It begins with stress to the ocular surface leading to the production of proinflammatory mediators that induce maturation of resident antigen-presenting cells which then migrate to the lymph nodes to activate CD4 T cells. The specific antigen(s) targeted by these pathogenic CD4+ T cells remains unknown. Two emerging theories include self-antigens by autoreactive CD4 T cells or harmless exogenous antigens in the setting of mucosal immunotolerance loss. These CD4 T cells migrate to the ocular surface causing additional inflammation and damage. Lifitegrast is the second topical anti-inflammatory agent to be approved by the US Food and Drug Administration for the treatment of DE and the first to show improvement in DE symptoms. Lifitegrast works by blocking the interaction between intercellular adhesion molecule-1 and lymphocyte functional associated antigen-1, which has been shown to be critical for the migration of antigen-presenting cells to the lymph nodes as well as CD4+ T cell activation and migration to the ocular surface. In four large multicenter, randomized controlled trials, lifitegrast has proven to be effective in controlling both the signs and symptoms of DE with minimal side effects. Further research should include comparative and combination studies with other anti-inflammatory therapies used for DE. PMID:29391773

Tumor evasion of the immune system by converting CD4+CD25- T cells into CD4+CD25+ T regulatory cells: role of tumor-derived TGF-beta.

PubMed

Liu, Victoria C; Wong, Larry Y; Jang, Thomas; Shah, Ali H; Park, Irwin; Yang, Ximing; Zhang, Qiang; Lonning, Scott; Teicher, Beverly A; Lee, Chung

2007-03-01

CD4+CD25+ T regulatory (T(reg)) cells were initially described for their ability to suppress autoimmune diseases in animal models. An emerging interest is the potential role of T(reg) cells in cancer development and progression because they have been shown to suppress antitumor immunity. In this study, CD4+CD25- T cells cultured in conditioned medium (CM) derived from tumor cells, RENCA or TRAMP-C2, possess similar characteristics as those of naturally occurring T(reg) cells, including expression of Foxp3, a crucial transcription factor of T(reg) cells, production of low levels of IL-2, high levels of IL-10 and TGF-beta, and the ability to suppress CD4+CD25- T cell proliferation. Further investigation revealed a critical role of tumor-derived TGF-beta in converting CD4+CD25- T cells into T(reg) cells because a neutralizing Ab against TGF-beta, 1D11, completely abrogated the induction of T(reg) cells. CM from a nontumorigenic cell line, NRP-152, or irradiated tumor cells did not convert CD4+CD25- T cells to T(reg) cells because they produce low levels of TGF-beta in CM. Finally, we observed a reduced tumor burden in animals receiving 1D11. The reduction in tumor burden correlated with a decrease in tumor-derived TGF-beta. Treatment of 1D11 also reduced the conversion of CD4+ T cells into T(reg) cells and subsequent T(reg) cell-mediated suppression of antitumor immunity. In summary, we have demonstrated that tumor cells directly convert CD4+CD25- T cells to T(reg) cells through production of high levels of TGF-beta, suggesting a possible mechanism through which tumor cells evade the immune system.

CD3-CD4+ lymphoid variant of hypereosinophilic syndrome: nodal and extranodal histopathological and immunophenotypic features of a peripheral indolent clonal T-cell lymphoproliferative disorder.

PubMed

Lefèvre, Guillaume; Copin, Marie-Christine; Roumier, Christophe; Aubert, Hélène; Avenel-Audran, Martine; Grardel, Nathalie; Poulain, Stéphanie; Staumont-Sallé, Delphine; Seneschal, Julien; Salles, Gilles; Ghomari, Kamel; Terriou, Louis; Leclech, Christian; Morati-Hafsaoui, Chafika; Morschhauser, Franck; Lambotte, Olivier; Ackerman, Félix; Trauet, Jacques; Geffroy, Sandrine; Dumezy, Florent; Capron, Monique; Roche-Lestienne, Catherine; Taieb, Alain; Hatron, Pierre-Yves; Dubucquoi, Sylvain; Hachulla, Eric; Prin, Lionel; Labalette, Myriam; Launay, David; Preudhomme, Claude; Kahn, Jean-Emmanuel

2015-08-01

The CD3(-)CD4(+) lymphoid variant of hypereosinophilic syndrome is characterized by hypereosinophilia and clonal circulating CD3(-)CD4(+) T cells. Peripheral T-cell lymphoma has been described during this disease course, and we observed in our cohort of 23 patients 2 cases of angio-immunoblastic T-cell lymphoma. We focus here on histopathological (n=12 patients) and immunophenotypic (n=15) characteristics of CD3(-)CD4(+) lymphoid variant of hypereosinophilic syndrome. Atypical CD4(+) T cells lymphoid infiltrates were found in 10 of 12 CD3(-)CD4(+) L-HES patients, in lymph nodes (n=4 of 4 patients), in skin (n=9 of 9) and other extra-nodal tissues (gut, lacrymal gland, synovium). Lymph nodes displayed infiltrates limited to the interfollicular areas or even an effacement of nodal architecture, associated with proliferation of arborizing high endothelial venules and increased follicular dendritic cell meshwork. Analysis of 2 fresh skin samples confirmed the presence of CD3(-)CD4(+) T cells. Clonal T cells were detected in at least one tissue in 8 patients, including lymph nodes (n=4 of 4): the same clonal T cells were detected in blood and in at least one biopsy, with a maximum delay of 23 years between samples. In the majority of cases, circulating CD3(-)CD4(+) T cells were CD2(hi) (n=9 of 14), CD5(hi) (n=12 of 14), and CD7(-)(n=4 of 14) or CD7(low) (n=10 of 14). Angio-immunoblastic T-cell lymphoma can also present with CD3(-)CD4(+) T cells; despite other common histopathological and immunophenotypic features, CD10 expression and follicular helper T-cell markers were not detected in lymphoid variant of hypereosinophilic syndrome patients, except in both patients who developed angio-immunoblastic T-cell lymphoma, and only at T-cell lymphoma diagnosis. Taken together, persistence of tissular clonal T cells and histopathological features define CD3(-)CD4(+) lymphoid variant of hypereosinophilic syndrome as a peripheral indolent clonal T-cell lymphoproliferative disorder, which should not be confused with angio-immunoblastic T-cell lymphoma. Copyright© Ferrata Storti Foundation.

CD3−CD4+ lymphoid variant of hypereosinophilic syndrome: nodal and extranodal histopathological and immunophenotypic features of a peripheral indolent clonal T-cell lymphoproliferative disorder

PubMed Central

Lefèvre, Guillaume; Copin, Marie-Christine; Roumier, Christophe; Aubert, Hélène; Avenel-Audran, Martine; Grardel, Nathalie; Poulain, Stéphanie; Staumont-Sallé, Delphine; Seneschal, Julien; Salles, Gilles; Ghomari, Kamel; Terriou, Louis; Leclech, Christian; Morati-Hafsaoui, Chafika; Morschhauser, Franck; Lambotte, Olivier; Ackerman, Félix; Trauet, Jacques; Geffroy, Sandrine; Dumezy, Florent; Capron, Monique; Roche-Lestienne, Catherine; Taieb, Alain; Hatron, Pierre-Yves; Dubucquoi, Sylvain; Hachulla, Eric; Prin, Lionel; Labalette, Myriam; Launay, David; Preudhomme, Claude; Kahn, Jean-Emmanuel

2015-01-01

The CD3−CD4+ lymphoid variant of hypereosinophilic syndrome is characterized by hypereosinophilia and clonal circulating CD3−CD4+ T cells. Peripheral T-cell lymphoma has been described during this disease course, and we observed in our cohort of 23 patients 2 cases of angio-immunoblastic T-cell lymphoma. We focus here on histopathological (n=12 patients) and immunophenotypic (n=15) characteristics of CD3−CD4+ lymphoid variant of hypereosinophilic syndrome. Atypical CD4+ T cells lymphoid infiltrates were found in 10 of 12 CD3−CD4+ L-HES patients, in lymph nodes (n=4 of 4 patients), in skin (n=9 of 9) and other extra-nodal tissues (gut, lacrymal gland, synovium). Lymph nodes displayed infiltrates limited to the interfollicular areas or even an effacement of nodal architecture, associated with proliferation of arborizing high endothelial venules and increased follicular dendritic cell meshwork. Analysis of 2 fresh skin samples confirmed the presence of CD3−CD4+ T cells. Clonal T cells were detected in at least one tissue in 8 patients, including lymph nodes (n=4 of 4): the same clonal T cells were detected in blood and in at least one biopsy, with a maximum delay of 23 years between samples. In the majority of cases, circulating CD3−CD4+ T cells were CD2hi (n=9 of 14), CD5hi (n=12 of 14), and CD7−(n=4 of 14) or CD7low (n=10 of 14). Angio-immunoblastic T-cell lymphoma can also present with CD3−CD4+ T cells; despite other common histopathological and immunophenotypic features, CD10 expression and follicular helper T-cell markers were not detected in lymphoid variant of hypereosinophilic syndrome patients, except in both patients who developed angio-immunoblastic T-cell lymphoma, and only at T-cell lymphoma diagnosis. Taken together, persistence of tissular clonal T cells and histopathological features define CD3−CD4+ lymphoid variant of hypereosinophilic syndrome as a peripheral indolent clonal T-cell lymphoproliferative disorder, which should not be confused with angio-immunoblastic T-cell lymphoma. PMID:25682606

B cells and TCR avidity determine distinct functions of CD4+ T cells in retroviral infection1

PubMed Central

Ploquin, Mickaël J-Y; Eksmond, Urszula; Kassiotis, George

2011-01-01

The T-cell-dependent B-cell response relies on cognate interaction between B cells and CD4+ Th cells. However, the consequences of this interaction for CD4+ T cells are not entirely known. B cells generally promote CD4+ T-cell responses to pathogens, albeit to a variable degree. In contrast, CD4+ T-cell responses to self or tumor antigens are often suppressed by B cells. Here we demonstrated that interaction with B cells dramatically inhibited the function of virus-specific CD4+ T cells in retroviral infection. We have used Friend virus (FV) infection of mice as a model for retroviral infection, in which the behavior of virus-specific CD4+ T cells was monitored according to their TCR avidity. We report that avidity for antigen and interaction with B cells determine distinct aspects of the primary CD4+ T-cell response to FV infection. Virus-specific CD4+ T cells followed exclusive Th1 and T follicular helper (Tfh) differentiation. High avidity for antigen facilitated expansion during priming and enhanced the capacity for IFN-γ and IL-21 production. In contrast, Tfh differentiation was not affected by avidity for antigen. By reducing or preventing B-cell interaction we found that B cells promoted Tfh differentiation, induced programmed death 1 (PD-1) expression and inhibited IFN-γ production by virus-specific CD4+ T cells. Ultimately, B cells protected hosts from CD4+ T-cell-mediated immune pathology, at the detriment of CD4+ T-cell-mediated protective immunity. Our results suggest that B-cell presentation of vaccine antigens could be manipulated to direct the appropriate CD4+ T-cell response. PMID:21841129

Effects of combined epidural and general anesthesia on intraoperative hemodynamic responses, postoperative cellular immunity, and prognosis in patients with gallbladder cancer: A randomized controlled trial.

PubMed

Zhu, Jun; Zhang, Xue-Rong; Yang, Hu

2017-03-01

This study is supposed to investigate the effects of combined epidural and general anesthesia on intraoperative hemodynamic responses, postoperative cellular immunity, and prognosis in patients with gallbladder cancer (GBC). One hundred forty-four GBC patients were selected and randomly divided into the general anesthesia (GA) group and the combined epidural-general anesthesia (CEGA) group. Before anesthesia induction (t0), at intubation (t1), at the beginning of surgery (t2), 5 minutes after pneumoperitoneum (t3), at the end of surgery (t4), after recovery of spontaneous breathing (t5), after regaining consciousness (t6), and after extubation (t7), the heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and the depth of anesthesia (bispectral index [BIS]) were detected. Blood samples were separately collected 30 minutes before anesthesia induction (T1), 2 hours after the beginning of surgery (T2), at the end of surgery (T3), 1 day after surgery (T4), 3 days after surgery (T5). The survival rates of T cell subsets (CD3+, CD4+, CD8+, CD4+/CD8+) and natural killer (NK) cells were determined by flow cytometry. Postoperative nausea and vomiting (PONV), visual analog scale (VAS), and sedation-agitation scale (SAS) were performed to assess postoperative adverse reactions. A 3-year follow-up was conducted. Compared with the GA group, the CEGA group had significant lower SBP values at t5 and t6, lower DBP values at t1, t3, t4, and t5, lower HR values at t1 and t5, and higher BIS values at t4, t5, t6, and t7. No PONV was observed in the CEGA group. In comparison to the GA group, the VAS was markedly increased and survival rates of CD3+, CD4+, and CD4+/CD8+ cells were increased at T2, T3, T4, and T5 in the CEGA group. The 1-year, 2-year, and 3-year survival rates were not evidently different between the CEGA group and the GA group. Our study provides evidence that the combined epidural-general anesthesia might attenuate intraoperative hemodynamic responses and improve postoperative cellular immunity, so that it might be a more available anesthesia method for GBC patients.

CD4+ T cell-mediated cytotoxicity is associated with MHC class II expression on malignant CD19+ B cells in diffuse large B cell lymphoma.

PubMed

Zhou, Yong; Zha, Jie; Lin, Zhijuan; Fang, Zhihong; Zeng, Hanyan; Zhao, Jintao; Luo, Yiming; Li, Zhifeng; Xu, Bing

2018-01-15

Diffuse large B cell lymphoma (DLBCL) is a common B cell malignancy with approximately 30% of patients present relapsed or refractory disease after first-line therapy. Research of further treatment options is needed. Cytotoxic CD4 + T cells express cytolytic molecules and have potential antitumor function. Here, we showed that the CD19 + cells from DLBCL patients presented significantly reduced expression of MHC II molecules than those from healthy controls. Three years after the first-line treatment, patients that presented relapsed disease had significantly lower MHC II expression on their CD19 + cells than patients who did not show recurrence. Examining cytotoxic CD4 + T cells show that DLBCL patients presented significantly elevated frequencies of granzyme A-, granzyme B-, and/or perforin-expressing cytotoxic CD4 + T cells. Also, frequency of cytotoxic CD4 + T cells in DLBCL patients was positively correlated with the MHC II expression level. Subsequently, the cytotoxic potential of CD4 + T cells against autologous CD19 + cells was investigated. We found that the cytotoxic potential of CD4 + T cells was highest in MHC II-high, intermediate in MHC II-mid, and lowest in MHC II-low patients. The percentage of MHC II-expressing viable CD19 + cells presented a significant reduction after longer incubation with cytotoxic CD4 + T cells, suggesting that cytotoxic CD4 + T cells preferentially eliminated MHC II-expressing CD19 + cells. Blocking MHC II on CD19 + cells significantly reduced the cytolytic capacity of CD4 + T cells. Despite these discoveries, the frequency of cytotoxic CD4 + T cells did not predict the clinical outcome of DLBCL patients. Together, these results demonstrated that cytotoxic CD4 + T cells presented an MHC II-dependent cytotoxic potential against autologous CD19 + cells and could potentially represent a future treatment option for DLBCL. Copyright © 2017 Elsevier Inc. All rights reserved.

Distinct susceptibility of HIV vaccine vector-induced CD4 T cells to HIV infection

PubMed Central

Niu, Qingli; Hou, Wei; Churchyard, Gavin; Nitayaphan, Sorachai; Pitisuthithum, Punnee; Rerks-Ngarm, Supachai; Franchini, Genoveffa

2018-01-01

The concerns raised from adenovirus 5 (Ad5)-based HIV vaccine clinical trials, where excess HIV infections were observed in some vaccine recipients, have highlighted the importance of understanding host responses to vaccine vectors and the HIV susceptibility of vector-specific CD4 T cells in HIV vaccination. Our recent study reported that human Ad5-specific CD4 T cells induced by Ad5 vaccination (RV156A trial) are susceptible to HIV. Here we further investigated the HIV susceptibility of vector-specific CD4 T cells induced by ALVAC, a canarypox viral vector tested in the Thai trial RV144, as compared to Ad5 vector-specific CD4 T cells in the HVTN204 trial. We showed that while Ad5 vector-specific CD4 T cells were readily susceptible to HIV, ALVAC-specific CD4 T cells in RV144 PBMC were substantially less susceptible to both R5 and X4 HIV in vitro. The lower HIV susceptibility of ALVAC-specific CD4 T cells was associated with the reduced surface expression of HIV entry co-receptors CCR5 and CXCR4 on these cells. Phenotypic analyses identified that ALVAC-specific CD4 T cells displayed a strong Th1 phenotype, producing higher levels of IFN-γ and CCL4 (MIP-1β) but little IL-17. Of interest, ALVAC and Ad5 vectors induced distinct profiles of vector-specific CD8 vs. CD4 T-cell proliferative responses in PBMC, with ALVAC preferentially inducing CD8 T-cell proliferation, while Ad5 vector induced CD4 T-cell proliferation. Depletion of ALVAC-, but not Ad5-, induced CD8 T cells in PBMC led to a modest increase in HIV infection of vector-specific CD4 T cells, suggesting a role of ALVAC-specific CD8 T cells in protecting ALVAC-specific CD4 T cells from HIV. Taken together, our data provide strong evidence for distinct HIV susceptibility of CD4 T cells induced by different vaccine vectors and highlight the importance of better evaluating anti-vector responses in HIV vaccination. PMID:29474461

Regulation of CD4 T cells and their effects on immunopathological inflammation following viral infection.

PubMed

Bhattacharyya, Mitra; Madden, Patrick; Henning, Nathan; Gregory, Shana; Aid, Malika; Martinot, Amanda J; Barouch, Dan H; Penaloza-MacMaster, Pablo

2017-10-01

CD4 T cells help immune responses, but knowledge of how memory CD4 T cells are regulated and how they regulate adaptive immune responses and induce immunopathology is limited. Using adoptive transfer of virus-specific CD4 T cells, we show that naive CD4 T cells undergo substantial expansion following infection, but can induce lethal T helper type 1-driven inflammation. In contrast, memory CD4 T cells exhibit a biased proliferation of T follicular helper cell subsets and were able to improve adaptive immune responses in the context of minimal tissue damage. Our analyses revealed that type I interferon regulates the expansion of primary CD4 T cells, but does not seem to play a critical role in regulating the expansion of secondary CD4 T cells. Strikingly, blockade of type I interferon abrogated lethal inflammation by primary CD4 T cells following viral infection, despite that this treatment increased the numbers of primary CD4 T-cell responses. Altogether, these data demonstrate important aspects of how primary and secondary CD4 T cells are regulated in vivo, and how they contribute to immune protection and immunopathology. These findings are important for rational vaccine design and for improving adoptive T-cell therapies against persistent antigens. © 2017 John Wiley & Sons Ltd.

Antiviral therapy during primary simian immunodeficiency virus infection fails to prevent acute loss of CD4+ T cells in gut mucosa but enhances their rapid restoration through central memory T cells.

PubMed

Verhoeven, David; Sankaran, Sumathi; Silvey, Melanie; Dandekar, Satya

2008-04-01

Gut-associated lymphoid tissue (GALT) is an early target of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) and a site for severe CD4+ T-cell depletion. Although antiretroviral therapy (ART) is effective in suppressing HIV replication and restoring CD4+ T cells in peripheral blood, restoration in GALT is delayed. The role of restored CD4+ T-cell help in GALT during ART and its impact on antiviral CD8+ T-cell responses have not been investigated. Using the SIV model, we investigated gut CD4+ T-cell restoration in infected macaques, initiating ART during either the primary stage (1 week postinfection), prior to acute CD4+ cell loss (PSI), or during the chronic stage at 10 weeks postinfection (CSI). ART led to viral suppression in GALT and peripheral blood mononuclear cells of PSI and CSI animals at comparable levels. CSI animals had incomplete CD4+ T-cell restoration in GALT. In PSI animals, ART did not prevent acute CD4+ T-cell loss by 2 weeks postinfection in GALT but supported rapid and complete CD4+ T-cell restoration thereafter. This correlated with an accumulation of central memory CD4+ T cells and better suppression of inflammation. Restoration of CD4+ T cells in GALT correlated with qualitative changes in SIV gag-specific CD8+ T-cell responses, with a dominance of interleukin-2-producing responses in PSI animals, while both CSI macaques and untreated SIV-infected controls were dominated by gamma interferon responses. Thus, central memory CD4+ T-cell levels and qualitative antiviral CD8+ T-cell responses, independent of viral suppression, were the immune correlates of gut mucosal immune restoration during ART.

Selective Expansion of Memory CD4+ T cells By Mitogenic Human CD28 Generates Inflammatory Cytokines and Regulatory T cells

PubMed Central

Singh, Manisha; Basu, Sreemanti; Camell, Christina; Couturier, Jacob; Nudelman, Rodolfo J.; Medina, Miguel A.; Rodgers, John R.; Lewis, Dorothy E.

2009-01-01

Co-stimulatory signals are important for development of effector and regulatory T cells. In this case, CD28 signaling is usually considered inert in the absence of signaling through the TCR. By contrast, mitogenic rat CD28 mAbs reportedly expand regulatory T cells without TCR stimulation. We found that a commercially available human CD28 mAb (ANC28) stimulated PBMCs without TCR co-ligation or cross-linking; ANC28 selectively expanded CD4+CD25+FoxP3−(T effector) and CD4+CD25+FoxP3+ (Treg) cells. ANC28 stimulated the CD45RO+ CD4+ (memory) population whereas CD45RA+CD4+ (naïve) cells did not respond. ANC28 also induced inflammatory cytokines. Treg induced by ANC28 retain the Treg phenotype longer than did co-stimulated Treg. Treg induced by ANC28 suppressed CD25− T cells through a contact-dependent mechanism. Purity influenced the response of CD4+CD25+ cells because bead-purified CD4+CD25+ cells (85–90% pure) responded strongly to ANC28, whereas 98% pure FACS-sorted CD4+CD25 bright (T-reg) did not respond. Purified CD4+CD25int cells responded similarly to the bead-purified CD4+CD25+ cells. Thus, pre-activated CD4+ T cells (CD25int) respond to ANC28 rather than Treg (CD25bright). The ability of ANC28 to expand both effectors producing inflammatory cytokines as well as suppressive regulatory T cells might be useful for ex vivo expansion of therapeutic T cells. PMID:18446791

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

PubMed

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

2012-02-01

In this present investigation, flow cytometry was utilized to evaluate 13 healthy controls and 31 HIV-1 infected patients who had advanced to the AIDS stage of infection (CD4 count below 200 cells/mm(3)), for the expression of CD161 on CD3(+) double negative (DN) (CD3(+)CD4(-)CD8(-)) T cells, CD4(+) T cells, CD8(+) T cells and γδ T cells. The observed depletion of CD161(+) T cells from peripheral circulation was due primarily to the loss of CD4(+)CD161(+) T cells; as these cells represented 8.67±0.74% of the total healthy control peripheral T cell population, while the CD4(+)CD161(+) T cells of the AIDS group represented only 3.35±0.41% (p=<0.0001) of the total peripheral T cell population. We have also shown here that the DN T cell population was more than doubled in the AIDS group, with the DN T cell population expanding from 3.29±0.45% of the healthy control peripheral T cell population to 8.64±1.16% (p=0.0001) of the AIDS group peripheral T cell population. By evaluating the expression of CD161 on the surface of the DN T cells we showed that within the healthy control group, 47.4±4.99% of the DN T cells were positive for the expression of CD161, while only 26.4±3.54% (p=0.002) of the AIDS group's DN T cells expressed CD161. Despite CD161 expression being halved on the DN T cells of the AIDS group, when we compared the total peripheral T cell percentage of CD161(+) DN T cells between the healthy control group and the AIDS group, there was no statistical difference. Even though only 26.4% DN T cells within the AIDS group were positive for CD161(+), the overall DN T cell population had expanded to such an extent that there was no statistical difference between the groups with regard to CD161(+) DN T cells as a percentage of the total peripheral T cell population. Furthermore, we showed that within the DN T cell population, there was an approximate 2:1 ratio of γδ to αβ T cells, and this ratio was maintained in both the healthy control group and the AIDS group. While evaluating γδ T cells we also discovered that CD8(+) γδ T cells were expanded from 0.62±.09% of the healthy control peripheral T cell population to 5.01±.88% (p=<0.0001) of the peripheral T cell population of the AIDS group; and that this population of CD8(+) γδ T cells underwent the same reduction in percentage of cells expressing CD161(+), further demonstrated that the phenomenon of CD161(+) percentage reduction and compensatory increase in total cell population was affecting the entire circulating γδ T cell population. Copyright © 2011 Elsevier Inc. All rights reserved.

Serosal Cavities Contain Two Populations of Innate-like integrin α4highCD4+ T Cells, Integrin α4β1+α6β1+α4β7- and α4β1+α6β1-α4β7+ Cells.

PubMed

Yang, Jeong In; Park, Chanho; Kho, Inseong; Lee, Sujin; Suh, Kyung-Suk; Kim, Tae Jin

2017-12-01

We previously reported peritoneal innate-like integrin α4 (CD49d) high CD4 + T cells that provided help for B-1a cells. Here we analyzed the expression of various integrin chains on the peritoneal and pleural integrin α4 high CD4 + T cells and investigated the functional heterogeneity of the subpopulations based on the integrin expression. Pleural cavity contained a lower ratio of integrin α4 high CD4 + T cells to integrin α4 low CD4 + T cells than peritoneal cavity, but the pleural integrin α4 high CD4 + T cells have the same characteristics of the peritoneal integrin α4 high CD4 + T cells. Most of integrin α4 high CD4 + T cells were integrin β1 high β7 - , but a minor population of integrin α4 high CD4 + T cells was integrin β1 + β7 + . Interestingly, the integrin α4 high β1 high β7 - CD4 + T cells expressed high levels of integrin α4β1 and α6β1, whereas integrin α4 high β1 + β7 + CD4 + T cells expressed high levels of integrin α4β1 and α4β7, suggesting an alternative expression of integrin α6β1 or α4β7 in combination with α4β1 in respective major and minor populations of integrin α4 high CD4 + T cells. The minor population, integrin α4 high β1 + β7 + CD4 + T cells, were different from the integrin α4 high β1 high β7 - CD4 + T cells in that they secreted a smaller amount of Th1 cytokines upon stimulation and expressed lower levels of Th1-related chemokine receptors CCR5 and CXCR3 than the integrin α4 high β 1 high β 7 - CD4 + T cells. In summary, the innate-like integrin α4 high CD4 + T cells could be divided into 2 populations, integrin α4β1 + α6β1 + α4β7 - and α4β1 + α6β1 - α4β7 + cells. The functional significance of serosal integrin α4β7 + CD4 + T cells needed to be investigated especially in view of mucosal immunity.

The effect of burn injury on CD8+ and CD4+ T cells in an irradiation model of homeostatic proliferation.

PubMed

Buchanan, Ian B; Maile, Robert; Frelinger, Jeffrey A; Fair, Jeffrey H; Meyer, Anthony A; Cairns, Bruce A

2006-11-01

Homeostatic proliferation of T cells has recently been shown to be an important mechanism in the host response to infection. However, its role in the T cell response to burn injury is unknown. In this study, we examine the effect of burn injury on CD4+ and CD8+ T cell homeostatic proliferation after irradiation. Wild-type C57BL/6 female mice were irradiated with six grays ionizing radiation and 48 hours later, syngeneic whole splenocytes or purified CD4+ or CD8+ T cells labeled with carboxy-fluorescein diacetate, succinimidyl ester were adoptively transferred. Two days later, mice underwent a 20% burn injury, followed by splenocyte harvest 3 and 10 days after injury. Burn mice demonstrate increased splenic cellularity and CD8+ T cell proliferation after adoptive transfer of either purified CD8+ cells or whole spleen populations compared with unburned (sham) mice. In contrast, CD4+ T cell proliferation after burn injury is unchanged after adoptive transfer of whole spleen cells and drastically decreased after adoptive transfer of a purified CD4+ population compared with sham mice. Ten days after burn injury CD8+ T cells continue to demonstrate greater proliferation than CD4+ T cells. CD8+ T cells are more robust than CD4+ T cells in their proliferative response after burn injury. In addition, CD8+ T cell proliferation appears less reliant on other immune cells than purified CD4+ T cell proliferation. These data reiterate the importance of CD8+ T cells in the initial immune response to burn injury.

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

PubMed

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

2010-12-22

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

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

PubMed Central

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

2010-01-01

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

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

PubMed Central

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

2011-01-01

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

Inhibitory Phenotype of HBV-Specific CD4+ T-Cells Is Characterized by High PD-1 Expression but Absent Coregulation of Multiple Inhibitory Molecules

PubMed Central

Kurktschiev, Peter; Schraut, Winfried; Zachoval, Reinhart; Wendtner, Clemens; Wächtler, Martin; Spannagl, Michael; Denk, Gerald; Ulsenheimer, Axel; Bengsch, Bertram; Pircher, Hanspeter; Diepolder, Helmut M.; Grüner, Norbert H.; Jung, Maria-Christina

2014-01-01

Background T-cell exhaustion seems to play a critical role in CD8+ T-cell dysfunction during chronic viral infections. However, up to now little is known about the mechanisms underlying CD4+ T-cell dysfunction during chronic hepatitis B virus (CHB) infection and the role of inhibitory molecules such as programmed death 1 (PD-1) for CD4+ T-cell failure. Methods The expression of multiple inhibitory molecules such as PD-1, CTLA-4, TIM-3, CD244, KLRG1 and markers defining the grade of T-cell differentiation as CCR7, CD45RA, CD57 and CD127 were analyzed on virus-specific CD4+ T-cells from peripheral blood using a newly established DRB1*01-restricted MHC class II Tetramer. Effects of in vitro PD-L1/2 blockade were defined by investigating changes in CD4+ T-cell proliferation and cytokine production. Results CD4+ T-cell responses during chronic HBV infection was characterized by reduced Tetramer+CD4+ T-cell frequencies, effector memory phenotype, sustained PD-1 but low levels of CTLA-4, TIM-3, KLRG1 and CD244 expression. PD-1 blockade revealed individualized patterns of in vitro responsiveness with partly increased IFN-γ, IL-2 and TNF-α secretion as well as enhanced CD4+ T-cell expansion almost in treated patients with viral control. Conclusion HBV-specific CD4+ T-cells are reliably detectable during different courses of HBV infection by MHC class II Tetramer technology. CD4+ T-cell dysfunction during chronic HBV is basically linked to strong PD-1 upregulation but absent coregulation of multiple inhibitory receptors. PD-L1/2 neutralization partly leads to enhanced CD4+ T-cell functionality with heterogeneous patterns of CD4+ T-cell rejunivation. PMID:25144233

Cytokines affecting CD4+T regulatory cells in transplant tolerance. III. Interleukin-5 (IL-5) promotes survival of alloantigen-specific CD4+ T regulatory cells.

PubMed

Hall, Bruce M; Plain, Karren M; Tran, Giang T; Verma, Nirupama D; Robinson, Catherine M; Nomura, Masaru; Boyd, Rochelle; Hodgkinson, Suzanne J

2017-08-01

CD4 + T cells mediate antigen-specific allograft tolerance, but die in culture without activated lymphocyte derived cytokines. Supplementation of the media with cytokine rich supernatant, from ConA activated spleen cells, preserves the capacity of tolerant cells to transfer tolerance and suppress rejection. rIL-2 or rIL-4 alone are insufficient to maintain these cells, however. We observed that activation of naïve CD4 + CD25 + FOXP3 + Treg with alloantigen and the Th2 cytokine rIL-4 induces them to express interleukin-5 specific receptor alpha (IL-5Rα) suggesting that IL-5, a Th2 cytokine that is produced later in the immune response may promote tolerance mediating Treg. This study examined if recombinant IL-5(rIL-5) promoted survival of tolerant CD4 + , especially CD4 + CD25 + T cells. CD4 + T cells, from DA rats tolerant to fully allogeneic PVG heart allografts surviving over 100days without on-going immunosuppression, were cultured with PVG alloantigen and rIL-5. The ability of these cells to adoptively transfer tolerance to specific-donor allograft and suppress normal CD4 + T cell mediated rejection in adoptive DA hosts was examined. Tolerant CD4 + CD25 + T cells' response to rIL-5 and expression of IL-5Rα was also assessed. rIL-5 was sufficient to promote transplant tolerance mediating CD4 + T cells' survival in culture with specific-donor alloantigen. Tolerant CD4 + T cells cultured with rIL-5 retained the capacity to transfer alloantigen-specific tolerance and inhibited naïve CD4 + T cells' capacity to effect specific-donor graft rejection. rIL-5 promoted tolerant CD4 + CD25 + T cells' proliferation in vitro when stimulated with specific-donor but not third-party stimulator cells. Tolerant CD4 + CD25 + T cells expressed IL-5Rα. This study demonstrated that IL-5 promoted the survival of alloantigen-specific CD4 + CD25 + T cells that mediate transplant tolerance. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of extracorporeal photopheresis alone or in combination therapy on circulating CD4+Foxp3+CD25- T-cells in patients with leukemic cutaneous T-cell lymphoma

PubMed Central

Shiue, Lisa H.; Couturier, Jacob; Lewis, Dorothy E.; Wei, Caimiao; Ni, Xiao; Duvic, Madeleine

2015-01-01

Purpose Extracorporeal photopheresis (ECP) alone or in combination therapy is effective for treatment of leukemic cutaneous T-cell lymphoma (L-CTCL), but its mechanism(s) of action remain unclear. This study was designed to investigate the effect of ECP on regulatory T-cell and CD8+ T-cells in L-CTCL patients. Experimental Design Peripheral blood from 18 L-CTCL patients at baseline, Day 2, 1-month, 3-month, and 6-month post-ECP therapy were analyzed by flow cytometry for CD4+CD25+/high, CD4+Foxp3+CD25+/-, CD3+CD8+, CD3+CD8+CD69+, and CD3+CD8+IFN-γ+ T-cells. Clinical responses were assessed and correlated with changes in these T-cell subsets. Results Twelve of 18 patients achieved clinical responses. The average baseline number of CD4+CD25+/high T-cells of PBMCs in L-CTCL patients was normal (2.2%), but increased at 6-month post-therapy (4.3%, p<0.01). The average baseline number of CD4+Foxp3+ T-cells out of CD4+ T-cells in 9 evaluable patients was high (66.8±13.7%), mostly CD25 negative. The levels of CD4+Foxp3+ T cells in responders were higher (n=6, 93.1±5.7%) than non-responders (n=3, 14.2±16.0%, p<0.01), and they declined in parallel with malignant T-cells. The numbers of CD3+CD8+CD69+ and CD3+CD8+ IFN-γ+ T-cells increased at 3-month post-therapy in 5 of 6 patients studied. Conclusions ECP alone or in combination therapy might be effective in L-CTCL patients whose malignant T-cells have a CD4+Foxp3+CD25- phenotype. PMID:25772268

Phenotypic and functional characterization of a CD4+ CD25high FOXP3high regulatory T-cell population in the dog

PubMed Central

Pinheiro, Dammy; Singh, Yogesh; Grant, Charlotte R; Appleton, Richard C; Sacchini, Flavio; Walker, Kate R L; Chadbourne, Alden H; Palmer, Charlotte A; Armitage-Chan, Elizabeth; Thompson, Ian; Williamson, Lina; Cunningham, Fiona; Garden, Oliver A

2011-01-01

Relatively little is known about regulatory T (Treg) cells and their functional responses in dogs. We have used the cross-reactive anti-mouse/rat Foxp3 antibody clone FJK-16s to identify a population of canine CD4+ FOXP3high T cells in both the peripheral blood (PB) and popliteal lymph node (LN). FOXP3+ cells in both PB and LN yielded positive staining with the newly developed anti-murine/human Helios antibody clone 22F6, consistent with the notion that they were naturally occurring Treg cells. Stimulation of mononuclear cells of LN origin with concanavalin A (Con A) in vitro yielded increased proportions and median fluorescence intensity of FOXP3 expression by both CD4+ and CD8+ T cells. Removal of the Con A and continued culture disclosed a CD4+ FOXP3high population, distinct from the CD4+ FOXP3intermediate T cells; very few CD8+ FOXP3high T cells were observed, though CD8+ FOXP3intermediate cells were present in equal abundance to CD4+ FOXP3intermediate cells. The CD4+ FOXP3high T cells were thought to represent activated Treg cells, in contrast to the FOXP3intermediate cells, which were thought to be a more heterogeneous population comprising predominantly activated conventional T cells. Co-staining with interferon-γ (IFN-γ) supported this notion, because the FOXP3high T cells were almost exclusively IFN-γ−, whereas the FOXP3intermediate cells expressed a more heterogeneous IFN-γ phenotype. Following activation of mononuclear cells with Con A and interleukin-2, the 5% of CD4+ T cells showing the highest CD25 expression (CD4+ CD25high) were enriched in cells expressing FOXP3. These cells were anergic in vitro, in contrast to the 20% of CD4+ T cells with the lowest CD25 expression (CD4+ CD25−), which proliferated readily. The CD4+ CD25high FOXP3high T cells were able to suppress the proliferation of responder CD4+ T cells in vitro, in contrast to the CD4+ CD25− cells, which showed no regulatory properties. PMID:20880379

TNF-α blockade induces IL-10 expression in human CD4+ T cells

NASA Astrophysics Data System (ADS)

Evans, Hayley G.; Roostalu, Urmas; Walter, Gina J.; Gullick, Nicola J.; Frederiksen, Klaus S.; Roberts, Ceri A.; Sumner, Jonathan; Baeten, Dominique L.; Gerwien, Jens G.; Cope, Andrew P.; Geissmann, Frederic; Kirkham, Bruce W.; Taams, Leonie S.

2014-02-01

IL-17+ CD4+ T (Th17) cells contribute to the pathogenesis of several human inflammatory diseases. Here we demonstrate that TNF inhibitor (TNFi) drugs induce the anti-inflammatory cytokine IL-10 in CD4+ T cells including IL-17+ CD4+ T cells. TNFi-mediated induction of IL-10 in IL-17+ CD4+ T cells is Treg-/Foxp3-independent, requires IL-10 and is overcome by IL-1β. TNFi-exposed IL-17+ CD4+ T cells are molecularly and functionally distinct, with a unique gene signature characterized by expression of IL10 and IKZF3 (encoding Aiolos). We show that Aiolos binds conserved regions in the IL10 locus in IL-17+ CD4+ T cells. Furthermore, IKZF3 and IL10 expression levels correlate in primary CD4+ T cells and Aiolos overexpression is sufficient to drive IL10 in these cells. Our data demonstrate that TNF-α blockade induces IL-10 in CD4+ T cells including Th17 cells and suggest a role for the transcription factor Aiolos in the regulation of IL-10 in CD4+ T cells.

Separation of human CD4+CD39+ T cells by magnetic beads reveals two phenotypically and functionally different subsets

PubMed Central

Schuler, Patrick J.; Harasymczuk, Malgorzata; Schilling, Bastian; Lang, Stephan; Whiteside, Theresa L.

2011-01-01

Objective The ectonucleotidase CD39 is an enzyme involved in adenosine production. Its surface expression on human regulatory T cells (Treg) allows for their flow-cytometry-based isolation from peripheral blood. To further develop and improve this method on a scale supporting translational studies, we introduced capture of CD39+ Treg on magnetic immunobeads. Methods Peripheral blood mononuclear cells (PBMC) obtained from healthy donors were used for negative selection of CD4+ T cells on AutoMACS using antibodies (Abs) specific for all lineage+ cells. CD4+CD39+ Treg were captured by biotin-conjugated anti-CD39 Abs and anti-biotin Ab-coated magnetic beads. Isolated CD4+CD39+ T cells were phenotyped by flow cytometry for Treg-associated markers: CD39, CD73, FOXP3, CD25, CTLA-4, CCR4, CD45RO and CD121a or for the absence of CD127 and CD49d. CFSE-based proliferation assays and ATP hydrolysis were used to measure Treg functions. Results The purity, recovery and viability of the separated CD4+CD39+ T cells were satisfactory. The isolated CD4+CD39+ T cell population consisted of FOXP3+CD25+ T cells which hydrolyzed exogenous ATP and suppressed autologous CD4+ T cell proliferation and of FOXP3negCD25neg T cells without suppressor function. The same two subsets were detectable by flow cytometry in normal PBMC, gating on CD4+CD39+, CD4+CD127neg, CD4+CD49dneg or CD4+CD25high Treg. Conclusion CD4+CD39+ Treg capture on immunobeads led to a discovery of two CD39+ subsets. Similar to CD39+ Treg in the peripheral blood, half of these cells are CD25+FOXP3+ active suppressor cells, while the other half are CD25negFOXP3neg and do not mediate suppression. PMID:21513715

IL-1R and MyD88 signalling in CD4+ T cells promote Th17 immunity and atherosclerosis.

PubMed

Engelbertsen, Daniel; Rattik, Sara; Wigren, Maria; Vallejo, Jenifer; Marinkovic, Goran; Schiopu, Alexandru; Björkbacka, Harry; Nilsson, Jan; Bengtsson, Eva

2018-01-01

The role of CD4+ T cells in atherosclerosis has been shown to be dependent on cytokine cues that regulate lineage commitment into mature T helper sub-sets. In this study, we tested the roles of IL-1R1 and MyD88 signalling in CD4+ T cells in atherosclerosis. We transferred apoe-/-myd88+/+ or apoe-/-myd88-/- CD4+ T cells to T- and B-cell-deficient rag1-/-apoe-/- mice fed high fat diet. Mice given apoe-/-myd88-/- CD4+ T cells exhibited reduced atherosclerosis compared with mice given apoe-/-myd88+/+ CD4+ T cells. CD4+ T cells from apoe-/-myd88-/- produced less IL-17 but similar levels of IFN-γ. Treatment of human CD4+ T cells with a MyD88 inhibitor inhibited IL-17 secretion in vitro. Transfer of il1r1-/- CD4+ T cells recapitulated the phenotype seen by transfer of myd88-/- CD4+ T cells with reduced lesion development and a reduction in Th17 and IL-17 production compared with wild type CD4+ T cell recipients. Relative collagen content of lesions was reduced in mice receiving il1r1-/- CD4+ T cells. We demonstrate that both IL1R and MyD88 signalling in CD4+ T cells promote Th17 immunity, plaque growth and may regulate plaque collagen levels. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For permissions please email: journals.permissions@oup.com.

Donor-Derived Regulatory Dendritic Cell Infusion Maintains Donor-Reactive CD4+CTLA4hi T Cells in Non-Human Primate Renal Allograft Recipients Treated with CD28 Co-Stimulation Blockade.

PubMed

Ezzelarab, Mohamed B; Lu, Lien; Shufesky, William F; Morelli, Adrian E; Thomson, Angus W

2018-01-01

Donor-derived regulatory dendritic cell (DCreg) infusion before transplantation, significantly prolongs renal allograft survival in non-human primates. This is associated with enhanced expression of the immunoregulatory molecules cytotoxic T-lymphocyte-associated antigen (Ag) 4 (CTLA4) and programmed cell death protein 1 (PD1) by host donor-reactive T cells. In rodents and humans, CD28 co-stimulatory pathway blockade with the fusion protein CTLA4:Ig (CTLA4Ig) is associated with reduced differentiation and development of regulatory T cells (Treg). We hypothesized that upregulation of CTLA4 by donor-reactive CD4 + T cells in DCreg-infused recipients treated with CTLA4Ig, might be associated with higher incidences of donor-reactive CD4 + T cells with a Treg phenotype. In normal rhesus monkeys, allo-stimulated CD4 + CTLA4 hi , but not CD4 + CTLA4 med/lo T cells exhibited a regulatory phenotype, irrespective of PD1 expression. CTLA4Ig significantly reduced the incidence of CD4 + CTLA4 hi , but not CD4 + CTLA4 med/lo T cells following allo-stimulation, associated with a significant reduction in the CD4 + CTLA4 hi /CD4 + CTLA4 med/lo T cell ratio. In CTLA4Ig-treated renal allograft recipient monkeys, there was a marked reduction in circulating donor-reactive CD4 + CTLA4 hi T cells. In contrast, in CTLA4Ig-treated monkeys with DCreg infusion, no such reduction was observed. In parallel, the donor-reactive CD4 + CTLA4 hi /CD4 + CTLA4 med/lo T cell ratio was reduced significantly in graft recipients without DCreg infusion, but increased in those given DCreg. These observations suggest that pre-transplant DCreg infusion promotes and maintains donor-reactive CD4 + CTLA4 hi T cells with a regulatory phenotype after transplantation, even in the presence of CD28 co-stimulation blockade.

Donor-Derived Regulatory Dendritic Cell Infusion Maintains Donor-Reactive CD4+CTLA4hi T Cells in Non-Human Primate Renal Allograft Recipients Treated with CD28 Co-Stimulation Blockade

PubMed Central

Ezzelarab, Mohamed B.; Lu, Lien; Shufesky, William F.; Morelli, Adrian E.; Thomson, Angus W.

2018-01-01

Donor-derived regulatory dendritic cell (DCreg) infusion before transplantation, significantly prolongs renal allograft survival in non-human primates. This is associated with enhanced expression of the immunoregulatory molecules cytotoxic T-lymphocyte-associated antigen (Ag) 4 (CTLA4) and programmed cell death protein 1 (PD1) by host donor-reactive T cells. In rodents and humans, CD28 co-stimulatory pathway blockade with the fusion protein CTLA4:Ig (CTLA4Ig) is associated with reduced differentiation and development of regulatory T cells (Treg). We hypothesized that upregulation of CTLA4 by donor-reactive CD4+ T cells in DCreg-infused recipients treated with CTLA4Ig, might be associated with higher incidences of donor-reactive CD4+ T cells with a Treg phenotype. In normal rhesus monkeys, allo-stimulated CD4+CTLA4hi, but not CD4+CTLA4med/lo T cells exhibited a regulatory phenotype, irrespective of PD1 expression. CTLA4Ig significantly reduced the incidence of CD4+CTLA4hi, but not CD4+CTLA4med/lo T cells following allo-stimulation, associated with a significant reduction in the CD4+CTLA4hi/CD4+CTLA4med/lo T cell ratio. In CTLA4Ig-treated renal allograft recipient monkeys, there was a marked reduction in circulating donor-reactive CD4+CTLA4hi T cells. In contrast, in CTLA4Ig-treated monkeys with DCreg infusion, no such reduction was observed. In parallel, the donor-reactive CD4+CTLA4hi/CD4+CTLA4med/lo T cell ratio was reduced significantly in graft recipients without DCreg infusion, but increased in those given DCreg. These observations suggest that pre-transplant DCreg infusion promotes and maintains donor-reactive CD4+CTLA4hi T cells with a regulatory phenotype after transplantation, even in the presence of CD28 co-stimulation blockade. PMID:29520267

CD147-mediated chemotaxis of CD4+CD161+ T cells may contribute to local inflammation in rheumatoid arthritis.

PubMed

Lv, Minghua; Miao, Jinlin; Zhao, Peng; Luo, Xing; Han, Qing; Wu, Zhenbiao; Zhang, Kui; Zhu, Ping

2018-01-01

CD161 is used as a surrogate marker for Th17 cells, which are implicated in the pathogenesis of rheumatoid arthritis (RA). In this study, we evaluated the percentage, clinical significance, and CD98 and CD147 expression of CD4 + CD161 + T cells. The potential role of CD147 and CD98 in cyclophilin A-induced chemotaxis of CD4 + CD161 + T cells was analyzed. Thirty-seven RA patients, 15 paired synovial fluid (SF) of RA, and 22 healthy controls were recruited. The cell populations and surface expression of CD98 and CD147 were analyzed by flow cytometry. Spearman's rank correlation coefficient and multiple linear regression were applied to calculate the correlations. Chemotaxis assay was used to investigate CD4 + CD161 + T cell migration. We found that the percentage of CD4 + CD161 + T cells and their expression of CD147 and CD98 in SF were higher than in the peripheral blood of RA patients. Percentage of SF CD4 + CD161 + T cells was positively correlated with 28-Joint Disease Activity Score (DAS28). CD147 monoclonal antibody (HAb18) attenuated the chemotactic ability of CD4 + CD161 + T cells. An increased CD4 + CD161 + T cell percentage and expression of CD147 and CD98 were shown in RA SF. Percentage of SF CD4 + CD161 + T cells can be used as a predictive marker of disease activity in RA. CD147 block significantly decreased the chemotactic index of CD4 + CD161 + cells induced by cyclophilin A (CypA). These results imply that the accumulation of CD4 + CD161 + T cells in SF and their high expression of CD147 may be associated with CypA-mediated chemotaxis and contribute to local inflammation in RA.

Functional Heterogeneity in the CD4+ T Cell Response to Murine γ-Herpesvirus 68

PubMed Central

Hu, Zhuting; Blackman, Marcia A.; Kaye, Kenneth M.; Usherwood, Edward J.

2015-01-01

CD4+ T cells are critical for the control of virus infections, T cell memory and immune surveillance. Here we studied the differentiation and function of murine γ-herpesvirus 68 (MHV-68)-specific CD4+ T cells using gp150-specific TCR transgenic mice. This allowed a more detailed study of the characteristics of the CD4+ T cell response than previously available approaches for this virus. Most gp150-specific CD4+ T cells expressed T-bet and produced IFN-γ, indicating MHV-68 infection triggered differentiation of CD4+ T cells largely into the Th1 subset, whereas some became TFH and Foxp3+ regulatory T cells. These CD4+ T cells were protective against MHV-68 infection, in the absence of CD8+ T cells and B cells, and protection depended on IFN-γ secretion. Marked heterogeneity was observed in the CD4+ T cells, based on Ly6C expression. Ly6C expression positively correlated with IFN-γ, TNF-α and granzyme B production, T-bet and KLRG1 expression, proliferation and CD4+ T cell-mediated cytotoxicity. Ly6C expression inversely correlated with survival, CCR7 expression and secondary expansion potential. Ly6C+ and Ly6C− gp150-specific CD4+ T cells were able to interconvert in a bidirectional manner upon secondary antigen exposure in vivo. These results indicate that Ly6C expression is closely associated with antiviral activity in effector CD4+ T cells, but inversely correlated with memory potential. Interconversion between Ly6C+ and Ly6C− cells may maintain a balance between the two antigen-specific CD4+ T cell populations during MHV-68 infection. These findings have significant implications for Ly6C as a surface marker to distinguish functionally distinct CD4+ T cells during persistent virus infection. PMID:25662997

Role of T-bet, the master regulator of Th1 cells, in the cytotoxicity of murine CD4+ T cells.

PubMed

Eshima, Koji; Misawa, Kana; Ohashi, Chihiro; Iwabuchi, Kazuya

2018-05-01

Although CD4 + T cells are generally regarded as helper T cells, some activated CD4 + T cells have cytotoxic properties. Given that CD4 + cytotoxic T lymphocytes (CTLs) often secrete IFN-γ, CTL activity among CD4 + T cells may be attributable to Th1 cells, where a T-box family molecule, T-bet serves as the "master regulator". However, although the essential contribution of T-bet to expression of IFN-γ has been well-documented, it remains unclear whether T-bet is involved in CD4 + T cell-mediated cytotoxicity. In this study, to investigate the ability of T-bet to confer cytolytic activity on CD4 + T cells, the T-bet gene (Tbx21) was introduced into non-cytocidal CD4 + T cell lines and their cytolytic function analyzed. Up-regulation of FasL (CD178), which provided the transfectant with cytotoxicity, was observed in Tbx21transfected CD4 + T cells but not in untransfected parental cells. In one cell line, T-bet transduction also induced perforin gene (Prf1) expression and Tbx21 transfectants efficiently killed Fas - target cells. Although T-bet was found to repress up-regulation of CD40L (CD154), which controls FasL-mediated cytolysis, the extent of CD40L up-regulation on in vitro-differentiated Th1 cells was similar to that on Th2 cells, suggesting the existence of a compensatory mechanism. These results collectively indicate that T-bet may be involved in the expression of genes, such as FasL and Prf1, which confer cytotoxicity on Th1 cells. © 2018 The Societies and John Wiley & Sons Australia, Ltd.

Genome-wide expression profiling analysis to identify key genes in the anti-HIV mechanism of CD4+ and CD8+ T cells.

PubMed

Gao, Lijie; Wang, Yunqi; Li, Yi; Dong, Ya; Yang, Aimin; Zhang, Jie; Li, Fengying; Zhang, Rongqiang

2018-07-01

Comprehensive bioinformatics analyses were performed to explore the key biomarkers in response to HIV infection of CD4 + and CD8 + T cells. The numbers of CD4 + and CD8 + T cells of HIV infected individuals were analyzed and the GEO database (GSE6740) was screened for differentially expressed genes (DEGs) in HIV infected CD4 + and CD8 + T cells. Gene Ontology enrichment, KEGG pathway analyses, and protein-protein interaction (PPI) network were performed to identify the key pathway and core proteins in anti-HIV virus process of CD4 + and CD8 + T cells. Finally, we analyzed the expressions of key proteins in HIV-infected T cells (GSE6740 dataset) and peripheral blood mononuclear cells(PBMCs) (GSE511 dataset). 1) CD4 + T cells counts and ratio of CD4 + /CD8 + T cells decreased while CD8 + T cells counts increased in HIV positive individuals; 2) 517 DEGs were found in HIV infected CD4 + and CD8 + T cells at acute and chronic stage with the criterial of P-value <0.05 and fold change (FC) ≥2; 3) In acute HIV infection, type 1 interferon (IFN-1) pathway might played a critical role in response to HIV infection of T cells. The main biological processes of the DEGs were response to virus and defense response to virus. At chronic stage, ISG15 protein, in conjunction with IFN-1 pathway might play key roles in anti-HIV responses of CD4 + T cells; and 4) The expression of ISG15 increased in both T cells and PBMCs after HIV infection. Gene expression profile of CD4 + and CD8 + T cells changed significantly in HIV infection, in which ISG15 gene may play a central role in activating the natural antiviral process of immune cells. © 2018 Wiley Periodicals, Inc.

Induction and function of virus-specific CD4+ T cell responses

PubMed Central

Whitmire, Jason K.

2010-01-01

CD4+ T cells -- often referred to as T-helper cells -- play a central role in immune defense and pathogenesis. Virus infections and vaccines stimulate and expand populations of antigen-specific CD4+ T cells in mice and in man. These virus-specific CD4+ T cells are extremely important in antiviral protection: deficiencies in CD4+ T cells are associated with virus reactivation, generalized susceptibility to opportunistic infections, and poor vaccine efficacy. As described below, CD4+ T cells influence effector and memory CD8+ T cell responses, humoral immunity, and the antimicrobial activity of macrophages and are involved in recruiting cells to sites of infection. This review summarizes a few key points about the dynamics of the CD4+ T cell response to virus infection, the positive role of pro-inflammatory cytokines in the differentiation of virus-specific CD4+ T cells, and new areas of investigation to improve vaccines against virus infection. PMID:21236461

Nocardia rubra cell-wall skeleton promotes CD4+ T cell activation and drives Th1 immune response.

PubMed

Wang, Guangchuan; Wu, Jie; Miao, Miao; Dou, Heng; Nan, Ning; Shi, Mingsheng; Yu, Guang; Shan, Fengping

2017-08-01

Several lines of evidences have shown that Nocardia rubra cell wall skeleton (Nr-CWS) has immunoregulatory and anti-tumor activities. However, there is no information about the effect of Nr-CWS on CD4 + T cells. The aim of this study was to explore the effect of Nr-CWS on the phenotype and function of CD4 + T cells. Our results of in vitro experiments showed that Nr-CWS could significantly up-regulate the expression of CD69 and CD25 on CD4 + T cells, promote the proliferation of CD4 + T cells, increase the production of IFN-γ, TNF-α and IL-2 in the supernatants, but has no significant effect on the apoptosis and death of CD4 + T cells. Results of in vivo experiments showed that Nr-CWS could promote the proliferation of CD4 + T cells, and increase the production of IL-2, IFN-γ and TNF-α (Th1 type cytokines). These data suggest that Nr-CWS can enhance the activation of CD4 + T cells, promote the proliferation of CD4 + T cells and the differentiation of CD4 + T cells to Th1 cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Synovial CD4+ T-cell-derived GM-CSF supports the differentiation of an inflammatory dendritic cell population in rheumatoid arthritis

PubMed Central

Reynolds, G; Gibbon, J R; Pratt, A G; Wood, M J; Coady, D; Raftery, G; Lorenzi, A R; Gray, A; Filer, A; Buckley, C D; Haniffa, M A; Isaacs, J D; Hilkens, C M U

2016-01-01

Objective A population of synovial inflammatory dendritic cells (infDCs) has recently been identified in rheumatoid arthritis (RA) and is thought to be monocyte-derived. Here, we investigated the role and source of granulocyte macrophage-colony-stimulating factor (GM-CSF) in the differentiation of synovial infDC in RA. Methods Production of GM-CSF by peripheral blood (PB) and synovial fluid (SF) CD4+ T cells was assessed by ELISA and flow cytometry. In vitro CD4+ T-cell polarisation experiments were performed with T-cell activating CD2/CD3/CD28-coated beads in the absence or presence of pro-Th1 or pro-Th17 cytokines. CD1c+ DC and CD16+ macrophage subsets were flow-sorted and analysed morphologically and functionally (T-cell stimulatory/polarising capacity). Results RA-SF CD4+ T cells produced abundant GM-CSF upon stimulation and significantly more than RA-SF mononuclear cells depleted of CD4+ T cells. GM-CSF-producing T cells were significantly increased in RA-SF compared with non-RA inflammatory arthritis SF, active RA PB and healthy donor PB. GM-CSF-producing CD4+ T cells were expanded by Th1-promoting but not Th17-promoting conditions. Following coculture with RA-SF CD4+ T cells, but not healthy donor PB CD4+ T cells, a subpopulation of monocytes differentiated into CD1c+ infDC; a process dependent on GM-CSF. These infDC displayed potent alloproliferative capacity and enhanced GM-CSF, interleukin-17 and interferon-γ production by CD4+ T cells. InfDC with an identical phenotype to in vitro generated cells were significantly enriched in RA-SF compared with non-RA-SF/tissue/PB. Conclusions We demonstrate a therapeutically tractable feedback loop of GM-CSF secreted by RA synovial CD4+ T cells promoting the differentiation of infDC with potent capacity to induce GM-CSF-producing CD4+ T cells. PMID:25923217

Expansion of natural killer cell receptor (CD94/NKG2A)-expressing cytolytic CD8 T cells and CD4+CD25+ regulatory T cells from the same cord blood unit.

PubMed

Tanaka, Junji; Sugita, Junichi; Kato, Naoko; Toubai, Tomomi; Ibata, Makoto; Shono, Yusuke; Ota, Shuichi; Kondo, Takeshi; Kobayashi, Takahiko; Kobayashi, Masanobu; Asaka, Masahiro; Imamura, Masahiro

2007-10-01

Cord blood contains a significant number of precursor cells that differentiate to cytotoxic effector cells and immunoregulatory cells. We tried to expand inhibitory natural killer cell receptor CD94-expressing CD8 T cells with cytolytic activity and CD4(+)CD25(+) regulatory T cells from the same cord cell unit. Cytotoxic CD94-expressing CD8 T cells were expanded from CD4-depleted cord blood using an immobilized anti-CD3 monoclonal antibody and a cytokine and also CD4(+)CD25(+) regulatory T cells were expanded from a CD4-enriched fraction derived from the same cord blood unit using anti-CD3/CD28 monoclonal antibody-coated Dynabeads and cytokines. We were able to obtain a more than 1000-fold expansion of CD94-expressing CD8 T cells and a more than 50-fold expansion of CD4(+)CD25(+) cells from the same cord blood unit. These expanded CD4(+)CD25(+) cells expressed FoxP3 mRNA at a level about 100-fold higher than that in isolated CD25(-) cells and could suppress allogeneic mixed lymphocyte culture by >80% (effector cells: CD4(+)CD25(+) cells = 2:1). Cytolytic activities of purified CD94-expressing cells detected by a 4-hour (51)Cr release assay against K562 were >60%. Coculture of CD94-expressing cells with expanded CD4(+)CD25(+) cells did not have any effect on cytolytic activities of purified CD94-expressing cells against K562 cells. These expanded cytolytic CD94-expressing CD8 cells might be able to induce a graft-vs-leukemia effect without enhancing graft-vs-host disease, and CD4(+)CD25(+) cells might be able to suppress allogeneic responses, including graft-vs-host disease and graft rejection after cord blood transplantation.

High Cell Surface Expression of CD4 Allows Distinction of CD4+CD25+ Antigen-specific Effector T Cells from CD4+CD25+ Regulatory T Cells in Murine Experimental Autoimmune Encephalomyelitis

PubMed Central

Li, Jinzhu; Ridgway, William; Fathman, C. Garrison; Tse, Harley Y.; Shaw, Michael K.

2008-01-01

Analysis of T regulatory cells (Treg) and T effector cells (Teff) in experimental autoimmune encephalomyelitis is complicated by the fact that both cell types express CD4 and CD25. We demonstrate that encephalitogenic T cells, following antigen recognition, up regulate cell surface expression of CD4. The CD4high sub-population contains all of the antigen response as shown by proliferation and cytokine secretion, and only these cells are capable of transferring EAE to naive animals. On the other hand, a FACS separable CD25+ sub-population of cells displayed consistent levels of CD4 prior to and after antigen stimulation. These cells displayed characteristics of Treg, such as expressing high levels of the Foxp3 gene and the ability to suppress mitogenic T cell responses. PMID:17920698

Regulatory CD4 T cells inhibit HIV-1 expression of other CD4 T cell subsets via interactions with cell surface regulatory proteins.

PubMed

Zhang, Mingce; Robinson, Tanya O; Duverger, Alexandra; Kutsch, Olaf; Heath, Sonya L; Cron, Randy Q

2018-03-01

During chronic HIV-1 infection, regulatory CD4 T cells (Tregs) frequently represent the largest subpopulation of CD4 T cell subsets, implying relative resistant to HIV-1. When HIV-1 infection of CD4 T cells was explored in vitro and ex vivo from patient samples, Tregs possessed lower levels of HIV-1 DNA and RNA in comparison with conventional effector and memory CD4 T cells. Moreover, Tregs suppressed HIV-1 expression in other CD4 T cells in an in vitro co-culture system. This suppression was mediated in part via multiple inhibitory surface proteins expressed on Tregs. Antibody blockade of CTLA-4, PD-1, and GARP on Tregs resulted in increased HIV-1 DNA integration and mRNA expression in neighboring CD4 T cells. Moreover, antibody blockade of Tregs inhibitory proteins resulted in increased HIV-1 LTR transcription in co-cultured CD4 T cells. Thus, Tregs inhibit HIV-1 infection of other CD4 T cell subsets via interactions with inhibitory cell surface proteins. Copyright © 2018 Elsevier Inc. All rights reserved.

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.

Impact of benznidazole treatment on the functional response of Trypanosoma cruzi antigen-specific CD4+CD8+ T cells in chronic Chagas disease patients.

PubMed

Pérez-Antón, Elena; Egui, Adriana; Thomas, M Carmen; Puerta, Concepción J; González, John Mario; Cuéllar, Adriana; Segovia, Manuel; López, Manuel Carlos

2018-05-11

Chagas disease is caused by Trypanosoma cruzi. The persistence of the parasite is associated with the disease chronicity and the impairment of the cellular immune response. It has been reported that the CD4+CD8+ T cell population expands in chronic Chagas disease patients. Few studies have focused on this subset of cells, and very little is known about the impact of antiparasitic treatment on this population. Thirty-eight chronic Chagas disease patients (20 asymptomatic and 18 symptomatic) and twelve healthy controls were enrolled in this study. Peripheral blood mononuclear cells were stimulated with soluble T. cruzi antigens to analyze the production of cytokines and cytotoxic molecules by CD4+CD8+ T cells before and after benznidazole treatment. Additionally, expression and co-expression of five inhibitory receptors in these patients after treatment were studied using a multiparameter flow cytometry technique. The frequency of CD4+CD8+ T cells was higher in chronic Chagas disease patients compared with healthy donors. Furthermore, a higher ratio of CD4+CD8low/CD4+CD8high subpopulations was observed in chronic Chagas disease patients than in healthy donors. Additionally, CD4+CD8+ T cells from these patients expressed and co-expressed higher levels of inhibitory receptors in direct proportion to the severity of the pathology. Benznidazole treatment reduced the frequency of CD4+CD8+ T cells and decreased the ratio of CD4+CD8low/CD4+CD8high subpopulations. The co-expression level of the inhibitory receptor was reduced after treatment simultaneously with the enhancement of the multifunctional capacity of CD4+CD8+ T cells. After treatment, an increase in the frequency of T. cruzi antigen-specific CD4+CD8+ T cells expressing IL-2 and TNF-α was also observed. CD4+CD8+ T cells could play an important role in the control of T. cruzi infection since they were able to produce effector molecules for parasite control. Benznidazole treatment partially reversed the exhaustion process caused by T. cruzi infection in these cells with an improvement in the functional response of the T. cruzi antigen-specific CD4+CD8+ T cells.

Impact of benznidazole treatment on the functional response of Trypanosoma cruzi antigen-specific CD4+CD8+ T cells in chronic Chagas disease patients

PubMed Central

Pérez-Antón, Elena; Egui, Adriana; Thomas, M. Carmen; Puerta, Concepción J.; González, John Mario; Cuéllar, Adriana; Segovia, Manuel

2018-01-01

Background Chagas disease is caused by Trypanosoma cruzi. The persistence of the parasite is associated with the disease chronicity and the impairment of the cellular immune response. It has been reported that the CD4+CD8+ T cell population expands in chronic Chagas disease patients. Few studies have focused on this subset of cells, and very little is known about the impact of antiparasitic treatment on this population. Methodology Thirty-eight chronic Chagas disease patients (20 asymptomatic and 18 symptomatic) and twelve healthy controls were enrolled in this study. Peripheral blood mononuclear cells were stimulated with soluble T. cruzi antigens to analyze the production of cytokines and cytotoxic molecules by CD4+CD8+ T cells before and after benznidazole treatment. Additionally, expression and co-expression of five inhibitory receptors in these patients after treatment were studied using a multiparameter flow cytometry technique. Principal findings The frequency of CD4+CD8+ T cells was higher in chronic Chagas disease patients compared with healthy donors. Furthermore, a higher ratio of CD4+CD8low/CD4+CD8high subpopulations was observed in chronic Chagas disease patients than in healthy donors. Additionally, CD4+CD8+ T cells from these patients expressed and co-expressed higher levels of inhibitory receptors in direct proportion to the severity of the pathology. Benznidazole treatment reduced the frequency of CD4+CD8+ T cells and decreased the ratio of CD4+CD8low/CD4+CD8high subpopulations. The co-expression level of the inhibitory receptor was reduced after treatment simultaneously with the enhancement of the multifunctional capacity of CD4+CD8+ T cells. After treatment, an increase in the frequency of T. cruzi antigen-specific CD4+CD8+ T cells expressing IL-2 and TNF-α was also observed. Conclusions CD4+CD8+ T cells could play an important role in the control of T. cruzi infection since they were able to produce effector molecules for parasite control. Benznidazole treatment partially reversed the exhaustion process caused by T. cruzi infection in these cells with an improvement in the functional response of the T. cruzi antigen-specific CD4+CD8+ T cells. PMID:29750791

LAG-3 Represents a Marker of CD4+ T Cells with Regulatory Activity in Patients with Bone Fracture.

PubMed

Wang, Jun; Ti, Yunfan; Wang, Yicun; Guo, Guodong; Jiang, Hui; Chang, Menghan; Qian, Hongbo; Zhao, Jianning; Sun, Guojing

2018-04-19

The lymphocyte activation gene 3 (LAG-3) is a CD4 homolog with binding affinity to MHC class II molecules. It is thought that LAG-3 exerts a bimodal function, such that co-ligation of LAG-3 and CD3 could deliver an inhibitory signal in conventional T cells, whereas, on regulatory T cells, LAG-3 expression could promote their inhibitory function. In this study, we investigated the role of LAG-3 expression on CD4 + T cells in patients with long bone fracture. We found that LAG-3 + cells represented approximately 13% of peripheral blood CD4 + T cells on average. Compared to LAG-3 - CD4 + T cells, LAG-3 + CD4 + T cells presented significantly higher Foxp3 and CTLA-4 expression. Directly ex vivo or with TCR stimulation, LAG-3 + CD4 + T cells expressed significantly higher levels of IL-10 and TGF-β than LAG-3 - CD4 + T cells. Interestingly, blocking the LAG-3-MHC class II interaction actually increased the IL-10 expression by LAG-3 + CD4 + T cells. The frequency of LAG-3 + CD4 + T cell was positively correlated with restoration of healthy bone function in long bone fracture patients. These results together suggested that LAG-3 is a marker of CD4 + T cells with regulatory function; at the same time, LAG-3 might have limited the full suppressive potential of Treg cells.

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

PubMed

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

2003-12-01

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

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

PubMed Central

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

2014-01-01

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

CD28 T-cell costimulatory molecule expression in pemphigus vulgaris.

PubMed

Alecu, M; Ursaciuc, C; Surcel, M; Coman, G; Ciotaru, D; Dobre, M

2009-03-01

CD28 superfamily of immune costimulatory molecules could play an important role in autotolerance control. CD28 costimulation seems to be necessary for regulatory T cell (Treg) activation and successive suppressive activities involved in autoimmunity protection. This study investigates CD28 expression, especially inducible costimulator fraction, on T lymphocytes in pemphigus vulgaris (PV) patients. CD28 expression on T lymphocytes was assessed in 16 PV patients during acute attack. All patients and 10 healthy control subjects were tested for lymphocyte populations, T-cell subpopulations (T-CD4+, T-CD8+), Treg and CD28 expression on T-cell subpopulations. T, B and natural killer cells average values in PV patients were close to the control group values. Compared with control group, PV values showed lower Treg (2.2% compared with 4.7%), slightly decreased CD4+ CD28+ T cells (91% compared with 95%), higher CD4+ CD28- T cells (9% compared with 5%), decreased CD8+ CD28+ T cells (57% and 73%, respectively) and significantly enhanced CD8+ CD28- T cells (43% compared with 27%). These data suggest that Treg-mediated suppressor T-cell effects could be diminished in PV, together with an abnormal or ineffective subsequent helper T-cell suppression. CD28 high expression on helper T cells and low expression on suppressor T cells are arguments for a potential CD28 role in PV autoimmune response mechanism.

Role of LAP+CD4+ T cells in the tumor microenvironment of colorectal cancer.

PubMed

Zhong, Wu; Jiang, Zhi-Yuan; Zhang, Lei; Huang, Jia-Hao; Wang, Shi-Jun; Liao, Cun; Cai, Bin; Chen, Li-Sheng; Zhang, Sen; Guo, Yun; Cao, Yun-Fei; Gao, Feng

2017-01-21

To investigate the abundance and potential functions of LAP + CD4 + T cells in colorectal cancer (CRC). Proportions of LAP + CD4 + T cells were examined in peripheral blood and tumor/paratumor tissues of CRC patients and healthy controls using flow cytometry. Expression of phenotypic markers such as forkhead box (Fox)p3, cytotoxic T-lymphocyte-associated protein (CTLA)-4, chemokine CC receptor (CCR)4 and CCR5 was measured using flow cytometry. LAP - CD4 + and LAP + CD4 + T cells were isolated using a magnetic cell-sorting system and cell purity was analyzed by flow cytometry. Real-time quantitative polymerase chain reaction was used to measure expression of cytokines interleukin (IL)-10 and transforming growth factor (TGF)-β. The proportion of LAP + CD4 + T cells was significantly higher in peripheral blood from patients (9.44% ± 3.18%) than healthy controls (1.49% ± 1.00%, P < 0.001). Among patients, the proportion of LAP + CD4 + T cells was significantly higher in tumor tissues (11.76% ± 3.74%) compared with paratumor tissues (3.87% ± 1.64%, P < 0.001). We also observed positive correlations between the proportion of LAP + CD4 + T cells and TNM stage ( P < 0.001), distant metastasis ( P < 0.001) and serum level of carcinoembryonic antigen ( P < 0.05). Magnetic-activated cell sorting gave an overall enrichment of LAP + CD4 + T cells (95.02% ± 2.87%), which was similar for LAP - CD4 + T cells (94.75% ± 2.76%). In contrast to LAP - CD4 + T cells, LAP + CD4 + T cells showed lower Foxp3 expression but significantly higher levels of CTLA-4, CCR4 and CCR5 ( P < 0.01). LAP + CD4 + T cells expressed significantly larger amounts of IL-10 and TGF-β but lower levels of IL-2, IL-4, IL-17 and interferon-γ, compared with LAP - CD4 + T cells. LAP + CD4 + T cells accumulated in the tumor microenvironment of CRC patients and were involved in immune evasion mediated by IL-10 and TGF-β.

CD8 apoptosis may be a predictor of T cell number normalization after immune reconstitution in HIV

PubMed Central

Lewis, Dorothy E; Gross, Kimber L; Diez, Martine M; Martinez, Maria L; Lukefahr, Helen N; Kozinetz, Claudia A; Arduino, Roberto C

2007-01-01

Background As part of the Houston Vanguard study, a subset of 10 patients randomized to receive IL-2 therapy were compared to 4 patients randomized to not receive IL-2, for markers of T cell activation and death during the first three cycles of IL-2. All patients were treated with combination antiretroviral therapy (ART) and were virally suppressed. The purpose of the study was to examine the role of CD8+ T cell death in responses to ART and IL-2 therapy. Methods Lymphocytes were examined at Day 0, 5 and 30 days during three cycles of IL-2 therapy. CD25, CD38, HLA-DR expression and annexin (cell death) were examined on CD4 and CD8 subpopulations. Follow up studies examined CD4 levels and CD4:CD8 reconstitution after 6 years using both univariant and multivariate analyses. Results Human lymphocytes responded to IL-2 therapy by upregulation of CD25 on CD4+ T cells, leading to an increase in CD4 cell counts. CD8+ T cells did not increase CD25 expression, but upregulated activation antigens (CD38 and DR) and had increased death. At baseline, 7 of the 14 patients had high CD8+ T cell apoptosis (mean 17.0% ± 6.0). We did an exploratory analysis of immune status after six years, and found that baseline CD8+ T cell apoptosis was correlated with CD4 cell count gain beginning two years post enrollment. Patients with low levels of CD8+ T cell apoptosis at baseline (mean 2.2% ± 2.1) had significantly higher CD4 cell counts and more normalized CD4:CD8 ratios than patients with high CD8+ T cell apoptosis (mean CD4 cell counts 1,209 ± 164 vs 754 ± 320 cells/mm3; CD4:CD8 ratios 1.55 vs. 0.70, respectively). Conclusion We postulate that CD8+ T cell apoptosis may reflect inherent activation status, which continues in some patients even though viral replication is suppressed which influences the ability of CD4+ T cells to rebound. Levels of CD8+ T cell apoptosis may therefore be an independent predictor of immune status, which should be shown in a prospective study. PMID:17263884

CD8 apoptosis may be a predictor of T cell number normalization after immune reconstitution in HIV.

PubMed

Lewis, Dorothy E; Gross, Kimber L; Diez, Martine M; Martinez, Maria L; Lukefahr, Helen N; Kozinetz, Claudia A; Arduino, Roberto C

2007-01-30

As part of the Houston Vanguard study, a subset of 10 patients randomized to receive IL-2 therapy were compared to 4 patients randomized to not receive IL-2, for markers of T cell activation and death during the first three cycles of IL-2. All patients were treated with combination antiretroviral therapy (ART) and were virally suppressed. The purpose of the study was to examine the role of CD8(+) T cell death in responses to ART and IL-2 therapy. Lymphocytes were examined at Day 0, 5 and 30 days during three cycles of IL-2 therapy. CD25, CD38, HLA-DR expression and annexin (cell death) were examined on CD4 and CD8 subpopulations. Follow up studies examined CD4 levels and CD4:CD8 reconstitution after 6 years using both univariant and multivariate analyses. Human lymphocytes responded to IL-2 therapy by upregulation of CD25 on CD4(+) T cells, leading to an increase in CD4 cell counts. CD8(+) T cells did not increase CD25 expression, but upregulated activation antigens (CD38 and DR) and had increased death. At baseline, 7 of the 14 patients had high CD8+ T cell apoptosis (mean 17.0% +/- 6.0). We did an exploratory analysis of immune status after six years, and found that baseline CD8+ T cell apoptosis was correlated with CD4 cell count gain beginning two years post enrollment. Patients with low levels of CD8(+) T cell apoptosis at baseline (mean 2.2% +/- 2.1) had significantly higher CD4 cell counts and more normalized CD4:CD8 ratios than patients with high CD8(+) T cell apoptosis (mean CD4 cell counts 1,209 +/- 164 vs 754 +/- 320 cells/mm(3); CD4:CD8 ratios 1.55 vs. 0.70, respectively). We postulate that CD8(+) T cell apoptosis may reflect inherent activation status, which continues in some patients even though viral replication is suppressed which influences the ability of CD4(+) T cells to rebound. Levels of CD8(+) T cell apoptosis may therefore be an independent predictor of immune status, which should be shown in a prospective study.

α4+β7hiCD4+ Memory T cells Harbor Most Th-17 cells and are Preferentially Infected During Acute SIV Infection

PubMed Central

Kader, Muhamuda; Wang, Xiaolei; Piatak, Michael; Lifson, Jeffrey; Roederer, Mario; Veazey, Ronald; Mattapallil, Joseph J.

2009-01-01

HIV/SIV are thought to infect minimally activated CD4+ T cells after viral entry. Not much is known about why SIV selectively targets these cells. Here we show that CD4+ T cells that express high levels of the α4β7 heterodimer are preferentially infected very early during the course of SIV infection. At day 2–4 post infection, α4+β7hiCD4+ T cells had ∼ 5x more SIV-gag DNA than β7−CD4+ T cells. α4+β7hiCD4+ T cells displayed a predominantly central memory (CD45RA−CD28+CCR7+) and resting (CD25−CD69−HLA-DR−Ki-67−) phenotype. Though the expression of detectable CCR5 was variable on α4+β7hi and β7−CD4+ T cells, both CCR5+ and CCR5− subsets of α4+β7hi and β7−CD4+ T cells were found to express sufficient levels of CCR5 mRNA suggesting that both these subsets could be efficiently infected by SIV. In line with this, we found similar levels of SIV infection in β7−CD4+CCR5+ and β7−CD4+CCR5− T cells. α4β7hiCD4+ T cells were found to harbor most Th-17 cells that were significantly depleted during acute SIV infection. Taken together, our results show that resting memory α4+β7hiCD4+ T cells in blood are preferentially depleted during acute SIV infection, and the loss of these cells alters the balance between Th-17 and Th-1 responses thereby contributing to disease pathogenesis. PMID:19571800

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

PubMed

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

2007-02-01

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

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

PubMed Central

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

2007-01-01

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

CD4+CD25hiFOXP3+ cells in cord blood of neonates born from filaria infected mother are negatively associated with CD4+Tbet+ and CD4+RORγt+ T cells.

PubMed

Ateba-Ngoa, Ulysse; Mombo-Ngoma, Ghyslain; Zettlmeissl, Eva; van der Vlugt, Luciën E P M; de Jong, Sanne E; de Jong, Sanne; Matsiegui, Pierre-Blaise; Ramharter, Michael; Kremsner, Peter G; Yazdanbakhsh, Maria; Adegnika, Ayola Akim

2014-01-01

Children who have been exposed in utero to maternal filarial infection are immunologically less responsive to filarial antigens, have less pathology, and are more susceptible to acquire infection than offspring of uninfected mothers. Moreover children from filaria infected mothers have been shown to be less responsive to vaccination as a consequence of an impairment of their immune response. However, it is not well known how in utero exposure to parasite antigens affects cellular immune responses. Here, 30 pregnant women were examined for the presence of microfilaria of Loa loa and Mansonella perstans in peripheral blood. At delivery, cord blood mononuclear cells (CBMC) were obtained and the CD4+T cells were phenotyped by expression of the transcription factors Tbet, RORγt, and FOXP3. No significant difference was observed between newborns from infected versus uninfected mothers in the frequencies of total CD4+T cells and CD4+T cells subsets including CD4+Tbet+, CD4+RORγt+ T and CD4+CD25hiFOXP3+ T cells. However, there was a negative association between CD4+CD25hiFOXP3+T cells and CD4+Tbet+ as well as CD4+RORγt+ T cells in the infected group only (B = -0.242, P = 0.002; B = -0.178, P = 0.013 respectively). Our results suggest that filarial infection during pregnancy leads to an expansion of functionally active regulatory T cells that keep TH1 and TH17 in check.

ML1419c peptide immunization induces Mycobacterium leprae-specific HLA-A*0201-restricted CTL in vivo with potential to kill live mycobacteria.

PubMed

Geluk, Annemieke; van den Eeden, Susan J F; Dijkman, Karin; Wilson, Louis; Kim, Hee Jin; Franken, Kees L M C; Spencer, John S; Pessolani, Maria C V; Pereira, Geraldo M B; Ottenhoff, Tom H M

2011-08-01

MHC class I-restricted CD8(+) T cells play an important role in protective immunity against mycobacteria. Previously, we showed that p113-121, derived from Mycobacterium leprae protein ML1419c, induced significant IFN-γ production by CD8(+) T cells in 90% of paucibacillary leprosy patients and in 80% of multibacillary patients' contacts, demonstrating induction of M. leprae-specific CD8(+) T cell immunity. In this work, we studied the in vivo role and functional profile of ML1419c p113-121-induced T cells in HLA-A*0201 transgenic mice. Immunization with 9mer or 30mer covering the p113-121 sequence combined with TLR9 agonist CpG induced HLA-A*0201-restricted, M. leprae-specific CD8(+) T cells as visualized by p113-121/HLA-A*0201 tetramers. Most CD8(+) T cells produced IFN-γ, but distinct IFN-γ(+)/TNF-α(+) populations were detected simultaneously with significant secretion of CXCL10/IFN-γ-induced protein 10, CXCL9/MIG, and VEGF. Strikingly, peptide immunization also induced high ML1419c-specific IgG levels, strongly suggesting that peptide-specific CD8(+) T cells provide help to B cells in vivo, as CD4(+) T cells were undetectable. An additional important characteristic of p113-121-specific CD8(+) T cells was their capacity for in vivo killing of p113-121-labeled, HLA-A*0201(+) splenocytes. The cytotoxic function of p113-121/HLA-A*0201-specific CD8(+) T cells extended into direct killing of splenocytes infected with live Mycobacterium smegmatis expressing ML1419c: both 9mer and 30mer induced CD8(+) T cells that reduced the number of ML1419c-expressing mycobacteria by 95%, whereas no reduction occurred using wild-type M. smegmatis. These data, combined with previous observations in Brazilian cohorts, show that ML1419c p113-121 induces potent CD8(+) T cells that provide protective immunity against M. leprae and B cell help for induction of specific IgG, suggesting its potential use in diagnostics and as a subunit (vaccine) for M. leprae infection.

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

PubMed

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

2007-09-03

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

LPS-treated bone marrow-derived dendritic cells induce immune tolerance through modulating differentiation of CD4+ regulatory T cell subpopulations mediated by 3G11 and CD127.

PubMed

Zhou, Fang; Zhang, Guang-Xian; Rostami, Abdolmohamad

2017-06-01

Intravenous transfer of LPS-treated bone marrow-derived dendritic cells blocks development of autoimmunity induced by CD4 + T cells in vivo. However, cellular mechanisms of dendritic cell-mediated immune tolerance have not yet been fully elucidated. Here, we report that there are two new subpopulations of CD4 + CD25 + FoxP3 + GITR + regulatory T cells (CD127 + 3G11 + and CD127 + 3G11 - cells). LPS-treated dendritic cells facilitate development of CD4 + CD127 + 3G11 - regulatory T cells but inhibit that of CD4 + CD127 + 3G11 + regulatory T cells. LPS-induced tolerogenic dendritic cells may cause immune tolerance through modulating balance of different subsets of CD4 + regulatory T cells mediated by CD127 and 3G11. Our results imply a new potential cellular mechanism of dendritic cell-mediated immune tolerance.

The impact of donor characteristics on the immune cell composition of mixture allografts of granulocyte-colony-stimulating factor-mobilized marrow harvests and peripheral blood harvests.

PubMed

Wang, Yu-Tong; Zhao, Xiang-Yu; Zhao, Xiao-Su; Xu, Lan-Ping; Zhang, Xiao-Hui; Wang, Yu; Liu, Kai-Yan; Chang, Ying-Jun; Huang, Xiao-Jun

2015-12-01

The association of donor characteristics with immune cell composition in allografts remains poorly understood. In this retrospective study, the effects of donor characteristics on immune cell composition in allografts were investigated. The correlations of donor characteristics with the immune cell composition in mixture allografts of granulocyte-colony-stimulating factor-mobilized marrow harvests and peripheral blood harvests of 390 healthy donors (male, 240; female, 150; median age, 40 years old) were analyzed. The median doses of CD3+ T cells, CD4+ T cells, CD8+ T cells, CD3+CD4-CD8- T cells, and monocytes in mixture allografts were 160.57 × 10(6), 89.29 × 10(6), 56.16 × 10(6), 10.87 × 10(6), and 137.94 × 10(6)/kg, respectively. Multivariate analysis showed that younger donor age was associated with a higher dose of CD3+ T cells (p = 0.006), CD3+CD8+ T cells (p < 0.001), CD3+CD4-CD8- T cells (p = 0.004), and monocytes (p = 0.014), as well as a higher ratio of CD3+CD4-CD8- T cells/CD3+ T cells (p < 0.001) in the mixture allografts. A negative association of donor weight with CD3+ T cells (p < 0.001), CD4+ T cells (p = 0.002), CD8+ T cells (p < 0.001), and CD3+CD4-CD8- T cells (p = 0.044) was observed. The count of peripheral blood lymphocyte pre-peripheral blood apheresis was correlated with the yield of CD3+ T cells (p < 0.001) and CD4+ T cells (p = 0.001). The peripheral blood monocyte count before marrow harvest predicted the monocyte dose (p = 0.002). The results suggested that older and overweight donors should not be chosen. The monocyte and lymphocyte counts before harvest could predict the yield of immune cells in allografts. © 2015 AABB.

Differential kinetics and specificity of EBV-specific CD4+ and CD8+ T cells during primary infection.

PubMed

Precopio, Melissa L; Sullivan, John L; Willard, Courtney; Somasundaran, Mohan; Luzuriaga, Katherine

2003-03-01

The generation and maintenance of virus-specific CD4(+) T cells in humans are not well understood. We used short in vitro stimulation assays followed by intracellular cytokine staining to characterize the timing, magnitude, and Ag specificity of CD4(+) T cells over the course of primary EBV infection. Lytic and latent protein-specific CD4(+) T cells were readily detected at presentation with acute infectious mononucleosis and declined rapidly thereafter. Responses to BZLF-1, BMLF-1, and Epstein-Barr nuclear Ag-3A were more commonly detected than responses to Epstein-Barr nuclear Ag-1. Concurrent analyses of BZLF-1-specific CD4(+) and CD8(+) T cells revealed differences in the expansion, specificity, and stability of CD4(+) and CD8(+) T cell-mediated responses over time. Peripheral blood EBV load directly correlated with the frequency of EBV-specific CD4(+) T cell responses at presentation and over time, suggesting that EBV-specific CD4(+) T cell responses are Ag-driven.

Galectin-7 promotes proliferation and Th1/2 cells polarization toward Th1 in activated CD4+ T cells by inhibiting The TGFβ/Smad3 pathway.

PubMed

Luo, Zhenlong; Ji, Yudong; Tian, Dean; Zhang, Yong; Chang, Sheng; Yang, Chao; Zhou, Hongmin; Chen, Zhonghua Klaus

2018-06-08

Galectin-7 (Gal-7) has been associated with cell proliferation and apoptosis. It is known that Gal-7 antagonises TGFβ-mediated effects in hepatocytes by interacting with Smad3. Previously, we have demonstrated that Gal-7 is related to CD4+ T cells responses; nevertheless, its effect and functional mechanism on CD4+ T cells responses remain unclear. The murine CD4+ T cells were respectively cultured with Gal-7, anti-CD3/CD28 mAbs, or with anti-CD3/CD28 mAbs & Gal-7. The effects of Gal-7 on proliferation and the phenotypic changes in CD4+ T cells were assessed by flow cytometry. The cytokines from CD4+ T cells were analysed by quantitative real-time PCR. Subcellular localisation and expression of Smad3 were determined by immunofluorescence staining and Western blot, respectively. Gal-7 enhanced the proliferation of activated CD4+ T cells in a dose- and β-galactoside-dependent manner. Additionally, Gal-7 treatment did not change the ratio of Th2 cells in activated CD4+ T cells, while it increased the ratio of Th1 cells. Gal-7 also induced activated CD4+ T cells to produce a higher level of IFN-γ and TNF-α and a lower level of IL-10. Moreover, Gal-7 treatment significantly accelerated nuclear export of Smad3 in activated CD4+ T cells. These results revealed a novel role of Gal-7 in promoting proliferation and Th1/2 cells polarization toward Th1 in activated CD4+ T cells by inhibiting the TGFβ/Smad3 pathway. Copyright © 2018 Elsevier Ltd. All rights reserved.

Single-cell analysis of lymphokine imbalance in asymptomatic HIV-1 infection: evidence for a major alteration within the CD8+ T cell subset

PubMed Central

Sousa, A E; Victorino, R M M

1998-01-01

In this study we investigated at single-cell level by flow cytometry the potential of T cell cytokine production in asymptomatic HIV-1-infected subjects with > 200 CD4 counts and possible correlation with T helper cell depletion and viral load. Mitogen-stimulated peripheral blood mononuclear cells from 32 HIV-1+ patients and 16 healthy subjects were intracytoplasmically stained for IL-2, interferon-gamma (IFN-γ), IL-4 or IL-10, and the frequency of cytokine-producing cells was assessed in total T cells, CD4, CD8 and CD45RO subsets as well as in CD69+CD3+ gated lymphocytes. HIV-1+ patients, irrespective of their degree of CD4 depletion, exhibited a major increase in IFN-γ+ CD8 T cells, largely due to CD28− cells, as well as a decrease in the capacity of CD8 T cells to produce IL-2. Patients with > 500 CD4 counts showed a diminished frequency of IL-4 expression in CD4 T cells and a negative correlation was found between this parameter and the ex vivo CD4 counts in the 32 patients. Analysis of patients stratified according to viral load revealed a significantly higher proportion of IL-2-producing CD4 cells in the group with < 5000 RNA copies/ml. In short, using single-cell analysis and an antigen-presenting cell-independent stimulus, we have not been able to find any significant cytokine imbalances in the CD4 subset, suggesting that the well described T helper defects are not due to intrinsic alterations in the potential of CD4 T cells to produce cytokines. On the other hand, the major disturbances in the CD8 T lymphocytes agree with the marked activation and possible replicative senescence of CD8 T cells and emphasize the role of this subset in HIV immunopathogenesis. PMID:9649194

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

PubMed

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

2011-03-01

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

Human leucocyte antigen class I-redirected anti-tumour CD4+ T cells require a higher T cell receptor binding affinity for optimal activity than CD8+ T cells.

PubMed

Tan, M P; Dolton, G M; Gerry, A B; Brewer, J E; Bennett, A D; Pumphrey, N J; Jakobsen, B K; Sewell, A K

2017-01-01

CD4 + T helper cells are a valuable component of the immune response towards cancer. Unfortunately, natural tumour-specific CD4 + T cells occur in low frequency, express relatively low-affinity T cell receptors (TCRs) and show poor reactivity towards cognate antigen. In addition, the lack of human leucocyte antigen (HLA) class II expression on most cancers dictates that these cells are often unable to respond to tumour cells directly. These deficiencies can be overcome by transducing primary CD4 + T cells with tumour-specific HLA class I-restricted TCRs prior to adoptive transfer. The lack of help from the co-receptor CD8 glycoprotein in CD4 + cells might result in these cells requiring a different optimal TCR binding affinity. Here we compared primary CD4 + and CD8 + T cells expressing wild-type and a range of affinity-enhanced TCRs specific for the HLA A*0201-restricted NY-ESO-1- and gp100 tumour antigens. Our major findings are: (i) redirected primary CD4 + T cells expressing TCRs of sufficiently high affinity exhibit a wide range of effector functions, including cytotoxicity, in response to cognate peptide; and (ii) optimal TCR binding affinity is higher in CD4 + T cells than CD8 + T cells. These results indicate that the CD4 + T cell component of current adoptive therapies using TCRs optimized for CD8 + T cells is below par and that there is room for substantial improvement. © 2016 The Authors. Clinical & Experimental Immunology published by John Wiley & Sons Ltd on behalf of British Society for Immunology.

Activation requirements and responses to TLR ligands in human CD4+ T cells: comparison of two T cell isolation techniques.

PubMed

Lancioni, Christina L; Thomas, Jeremy J; Rojas, Roxana E

2009-05-15

Direct regulation of T cell function by microbial ligands through Toll-like receptors (TLR) is an emerging area of T cell biology. Currently either immunomagnetic cell sorting (IMACS) or fluorescence-activated cell sorting (FACS), are utilized to isolate T-cell subsets for such studies. However, it is unknown to what extent differences in T cell purity between these isolation techniques influence T cell functional assays. We compared the purity, response to mitogen, activation requirements, and response to TLR ligands between human CD4(+) T cells isolated either by IMACS (IMACS-CD4(+)) or by IMACS followed by FACS (IMACS/FACS-CD4(+)). As expected, IMACS-CD4(+) were less pure than IMACS/FACS-CD4(+) (92.5%+/-1.4% versus 99.7%+/-0.2%, respectively). Consequently, IMACS-CD4(+) proliferated and produced cytokines in response to mitogen alone and had lower activation requirements compared to IMACS/FACS-CD4(+). In addition IMACS-CD4(+) but not IMACS/FACS-CD4(+) responses were upregulated by the TLR-4 ligand lipopolysaccharide (LPS). On the other hand, TLR-2 and TLR-5 engagement induced costimulation in both IMACS-CD4(+) and highly purified IMACS-/FACS-CD4(+). Altogether these results indicate that small differences in cell purity can significantly alter T cell responses to TLR ligands. This study stresses the importance of a stringent purification method when investigating the role of microbial ligands in T cell function.

Blimp-1–mediated CD4 T cell exhaustion causes CD8 T cell dysfunction during chronic toxoplasmosis

PubMed Central

Cobb, Dustin A.; Bhadra, Rajarshi

2016-01-01

CD8, but not CD4, T cells are considered critical for control of chronic toxoplasmosis. Although CD8 exhaustion has been previously reported in Toxoplasma encephalitis (TE)–susceptible model, our current work demonstrates that CD4 not only become exhausted during chronic toxoplasmosis but this dysfunction is more pronounced than CD8 T cells. Exhausted CD4 population expressed elevated levels of multiple inhibitory receptors concomitant with the reduced functionality and up-regulation of Blimp-1, a transcription factor. Our data demonstrates for the first time that Blimp-1 is a critical regulator for CD4 T cell exhaustion especially in the CD4 central memory cell subset. Using a tamoxifen-dependent conditional Blimp-1 knockout mixed bone marrow chimera as well as an adoptive transfer approach, we show that CD4 T cell–intrinsic deletion of Blimp-1 reversed CD8 T cell dysfunction and resulted in improved pathogen control. To the best of our knowledge, this is a novel finding, which demonstrates the role of Blimp-1 as a critical regulator of CD4 dysfunction and links it to the CD8 T cell dysfunctionality observed in infected mice. The critical role of CD4-intrinsic Blimp-1 expression in mediating CD4 and CD8 T cell exhaustion may provide a rational basis for designing novel therapeutic approaches. PMID:27481131

Correlates of preserved CD4(+) T cell homeostasis during natural, nonpathogenic simian immunodeficiency virus infection of sooty mangabeys: implications for AIDS pathogenesis.

PubMed

Sumpter, Beth; Dunham, Richard; Gordon, Shari; Engram, Jessica; Hennessy, Margaret; Kinter, Audrey; Paiardini, Mirko; Cervasi, Barbara; Klatt, Nichole; McClure, Harold; Milush, Jeffrey M; Staprans, Silvija; Sodora, Donald L; Silvestri, Guido

2007-02-01

In contrast to HIV-infected humans, naturally SIV-infected sooty mangabeys (SMs) very rarely progress to AIDS. Although the mechanisms underlying this disease resistance are unknown, a consistent feature of natural SIV infection is the absence of the generalized immune activation associated with HIV infection. To define the correlates of preserved CD4(+) T cell counts in SMs, we conducted a cross-sectional immunological study of 110 naturally SIV-infected SMs. The nonpathogenic nature of the infection was confirmed by an average CD4(+) T cell count of 1,076 +/- 589/mm(3) despite chronic infection with a highly replicating virus. No correlation was found between CD4(+) T cell counts and either age (used as a surrogate marker for length of infection) or viremia. The strongest correlates of preserved CD4(+) T cell counts were a low percentage of circulating effector T cells (CD28(-)CD95(+) and/or IL-7R/CD127(-)) and a high percentage of CD4(+)CD25(+) T cells. These findings support the hypothesis that the level of immune activation is a key determinant of CD4(+) T cell counts in SIV-infected SMs. Interestingly, we identified 14 animals with CD4(+) T cell counts of <500/mm(3), of which two show severe and persistent CD4(+) T cell depletion (<50/mm(3)). Thus, significant CD4(+) T cell depletion does occasionally follow SIV infection of SMs even in the context of generally low levels of immune activation, lending support to the hypothesis of multifactorial control of CD4(+) T cell homeostasis in this model of infection. The absence of AIDS in these "CD4(low)" naturally SIV-infected SMs defines a protective role of the reduced immune activation even in the context of a significant CD4(+) T cell depletion.

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

PubMed Central

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

2011-01-01

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

Low levels of SIV infection in sooty mangabey central-memory CD4+ T-cells is associated with limited CCR5 expression

PubMed Central

Paiardini, Mirko; Cervasi, Barbara; Reyes-Aviles, Elane; Micci, Luca; Ortiz, Alexandra M.; Chahroudi, Ann; Vinton, Carol; Gordon, Shari N.; Bosinger, Steven E.; Francella, Nicholas; Hallberg, Paul L.; Schlub, Timothy; Chan, Ming Liang; Riddick, Nadeene E.; Collman, Ronald G.; Apetrei, Cristian; Pandrea, Ivona; Else, James; Munch, Jan; Kirchhoff, Frank; Davenport, Miles P.; Brenchley, Jason M.; Silvestri, Guido

2011-01-01

Naturally SIV-infected sooty mangabeys (SMs) do not progress to AIDS despite high-level virus replication. We previously showed that the fraction of CD4+CCR5+ T-cells is lower in SMs compared to humans and macaques. Here we found that, after in vitro stimulation, SM CD4+ T-cells fail to up-regulate CCR5, and that this phenomenon is more pronounced in CD4+ central-memory T-cells (TCM). CD4+ T-cell activation was similarly uncoupled from CCR5 expression in SMs in vivo during (i) acute SIV infection and (ii) following antibody-mediated CD4+ T-cell depletion. Remarkably, CD4+ TCM of SMs that express low levels of CCR5 demonstrated reduced susceptibility to SIV infection both in vivo and in vitro when compared to CD4+ TCM of RMs. These data suggest that low CCR5 expression on SM CD4+ T-cells favors the preservation of CD4+ T-cell homeostasis and promotes an AIDS-free status by protecting CD4+ TCM from direct virus infection. PMID:21706028

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

Treatment of Primary Cutaneous CD4 Small/Medium T cell Lymphoproliferative Disorder with Intralesional Triamcinolone Acetonide.

DTIC Science & Technology

2018-02-15

12. REPORT TYPE 02/15/2018 Poster 4. TITLE AND SUBTITLE Treatment of Primary Cutaneous CD4+ Small/Medium T- cell Lymphoproliferative Disorder with...cutaneous CD4+ small/medium T- cell lymphoproliferative disorder (LPD) is a generally indolent cutaneous T- cell proliferation. Most cases follow a benign...lmmunohistochemistry showed diffuse CD3+ CD4+ T- cells without CD30, TIA1 or CD10. A subset of medium to large cells expressed BCL-6. Small subsets of B- cells and CDB

A Quantitative Comparison of Anti-HIV Gene Therapy Delivered to Hematopoietic Stem Cells versus CD4+ T Cells

PubMed Central

Savkovic, Borislav; Nichols, James; Birkett, Donald; Applegate, Tanya; Ledger, Scott; Symonds, Geoff; Murray, John M.

2014-01-01

Gene therapy represents an alternative and promising anti-HIV modality to highly active antiretroviral therapy. It involves the introduction of a protective gene into a cell, thereby conferring protection against HIV. While clinical trials to date have delivered gene therapy to CD4+T cells or to CD34+ hematopoietic stem cells (HSC), the relative benefits of each of these two cellular targets have not been conclusively determined. In the present analysis, we investigated the relative merits of delivering a dual construct (CCR5 entry inhibitor + C46 fusion inhibitor) to either CD4+T cells or to CD34+ HSC. Using mathematical modelling, we determined the impact of each scenario in terms of total CD4+T cell counts over a 10 year period, and also in terms of inhibition of CCR5 and CXCR4 tropic virus. Our modelling determined that therapy delivery to CD34+ HSC generally resulted in better outcomes than delivery to CD4+T cells. An early one-off therapy delivery to CD34+ HSC, assuming that 20% of CD34+ HSC in the bone marrow were gene-modified (G+), resulted in total CD4+T cell counts ≥180 cells/ µL in peripheral blood after 10 years. If the uninfected G+ CD4+T cells (in addition to exhibiting lower likelihood of becoming productively infected) also exhibited reduced levels of bystander apoptosis (92.5% reduction) over non gene-modified (G-) CD4+T cells, then total CD4+T cell counts of ≥350 cells/ µL were observed after 10 years, even if initially only 10% of CD34+ HSC in the bone marrow received the protective gene. Taken together our results indicate that: 1.) therapy delivery to CD34+ HSC will result in better outcomes than delivery to CD4+T cells, and 2.) a greater impact of gene therapy will be observed if G+ CD4+T cells exhibit reduced levels of bystander apoptosis over G- CD4+T cells. PMID:24945407

Nutritional and Immunological Correlates of Memory and Neurocognitive Development Among HIV-Infected Children Living in Kayunga, Uganda.

PubMed

Ruiseñor-Escudero, Horacio; Familiar-Lopez, Itziar; Sikorskii, Alla; Jambulingam, Nikita; Nakasujja, Noelline; Opoka, Robert; Bass, Judith; Boivin, Michael

2016-04-15

To identify the nutritional and immunological correlates of memory and neurocognitive development as measured by the Mullen Scales of Early Learning (MSEL) and by the Color Object Association Test (COAT) among children in Uganda. This analysis uses baseline data collected between 2008 and 2010 from 119 HIV-infected children aged 1-6 years, participating in a randomized controlled trial of an interventional parenting program in Kayunga, Uganda. Peripheral blood draws were performed to determine immunological biomarkers. Unadjusted and adjusted linear regression models were used to relate MSEL and COAT scores to sociodemographic characteristics, weight-for-age Z scores (WAZs), antiretroviral therapy status, and immunological biomarkers. In the final analysis, 111 children were included. Lower levels of CD4 CD38 T cells (P = 0.04) were associated to higher immediate and total recall scores (P = 0.04). Higher levels of CD8 HLA-DR T cells were associated with higher total recall score (P = 0.04) of the COAT. Higher CD4 CD38 HLA-DR T cells levels were associated with higher gross motor scores of the MSEL (P = 0.02). WAZ was positively correlated to visual reception, fine motor, expressive language, and composite score of the MSEL. Overall, WAZ was a stronger predictor of neurocognitive outcomes assessed by the MSEL. CD4 CD38 T cells were more specifically associated with memory-related outcomes. Future research should include immunological markers and standardized neurocognitive tests to further understand this relationship.

HIV-specific cytotoxic T lymphocyte precursors exist in a CD28-CD8+ T cell subset and increase with loss of CD4 T cells.

PubMed

Lewis, D E; Yang, L; Luo, W; Wang, X; Rodgers, J R

1999-06-18

To determine whether the CD28-CD8+ T cells that develop during HIV infection contain HIV-specific cytotoxic precursor cells. CD8 subpopulations from six asymptomatic HIV-positive adults, with varying degrees of CD4 T cell loss, were sorted by flow cytometry and HIV-specific precursor cytotoxic T lymphocyte frequencies were measured. Three populations of CD8 T cells were tested: CD28+CD5-- T cells, CD28-CD57+ T cells (thought to be memory cells) and CD28-CD57- T cells (function unknown). Sorted CD8 subsets were stimulated with antigen presenting cells expressing HIV-1 Gag/Pol molecules. Cytotoxic T cell assays on Gag/Pol expressing 51Cr-labeled Epstein-Barr virus transformed autologous B cells lines or control targets were performed after 2 weeks. Specific lysis and precursor frequencies were calculated. Both CD28 positive and CD28-CD57+ populations contained appreciable numbers of precursors (9-1720 per 10(6) CD8+ T cells). However, the CD28-CD57- population had fewer precursors in five out of six people studied. More CD28 positive HIV-specific cytotoxic T lymphocyte precursors were found in patients with CD4:CD8 ratios > 1, whereas more CD28-CD57+ precursors were found in patients whose CD4:CD8 ratios were < 1 (r2, 0.68). Memory HIV-specific precursor cytotoxic T lymphocytes are found in both CD28 positive and CD28-CD8+ cells, however, a CD28-CD57- subpopulation had fewer. Because CD28-CD57+ cells are antigen-driven with limited diversity, the loss of CD28 on CD8 T cells during disease progression may reduce the response to new HIV mutations; this requires further testing.

Ectopic expression of anti-HIV-1 shRNAs protects CD8{sup +} T cells modified with CD4ζ CAR from HIV-1 infection and alleviates impairment of cell proliferation

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

Kamata, Masakazu, E-mail: masa3k@ucla.edu; Kim, Patrick Y.; Ng, Hwee L.

Chimeric antigen receptors (CARs) are artificially engineered receptors that confer a desired specificity to immune effector T cells. As an HIV-1-specific CAR, CD4ζ CAR has been extensively tested in vitro as well as in clinical trials. T cells modified with this CAR mediated highly potent anti-HIV-1 activities in vitro and were well-tolerated in vivo, but exerted limited effects on viral load and reservoir size due to poor survival and/or functionality of the transduced cells in patients. We hypothesize that ectopic expression of CD4ζ on CD8{sup +} T cells renders them susceptible to HIV-1 infection, resulting in poor survival of those cells. To testmore » this possibility, highly purified CD8{sup +} T cells were genetically modified with a CD4ζ-encoding lentiviral vector and infected with HIV-1. CD8{sup +} T cells were vulnerable to HIV-1 infection upon expression of CD4ζ as evidenced by elevated levels of p24{sup Gag} in cells and culture supernatants. Concurrently, the number of CD4ζ-modified CD8{sup +} T cells was reduced relative to control cells upon HIV-1 infection. To protect these cells from HIV-1 infection, we co-expressed two anti-HIV-1 shRNAs previously developed by our group together with CD4ζ. This combination vector was able to suppress HIV-1 infection without impairing HIV-1-dependent effector activities of CD4ζ. In addition, the number of CD4ζ-modified CD8{sup +} T cells maintained similar levels to that of the control even under HIV-1 infection. These results suggest that protecting CD4ζ-modified CD8{sup +} T cells from HIV-1 infection is required for prolonged HIV-1-specific immune surveillance. - Highlights: • Ectopic expression of CD4ζ CAR in CD8{sup +} T cells renders them susceptible to HIV-1 infection. • Co-expression of two anti-HIV-1 shRNAs protects CD4ζ CAR-modified CD8{sup +} T cells from HIV-1 infection. • Protecting CD4ζ CAR-modified CD8{sup +} T cells from HIV-1 infection suppresses its cytopathic effect.« less

Platelets Play Differential Role During the Initiation and Progression of Autoimmune Neuroinflammation

PubMed Central

Starossom, Sarah C.; Veremeyko, Tatyana; Yung, Amanda W. Y.; Dukhinova, Marina; Au, Cheryl; Lau, Alexander Y.; Weiner, Howard L.; Ponomarev, Eugene D.

2015-01-01

Rationale Platelets are known to participate in vascular pathologies; however, their role in neuroinflammatory diseases such as multiples sclerosis (MS) is unknown. Autoimmune CD4 T cells have been the main focus of studies of MS, although the factors that regulate T cell differentiation towards pathogenic Th1/Th17 phenotypes are not completely understood. Objectives We investigated the role of platelets in the modulation of CD4 T cell functions in MS patients and in mice with experimental autoimmune encephalitis (EAE), an animal model for MS. Methods and Results We found that early in MS and EAE platelets degranulated and produced a number of soluble factors serotonin (5HT), PF4 and PAF, which specifically stimulated differentiation of T cells towards pathogenic Th1, Th17 and IFN-γ/IL-17-producing CD4 T cells. At the later stages of MS and EAE platelets became exhausted in their ability to produce proinflammatory factors and stimulate CD4 T cells, but substantially increased their ability to form aggregates with CD4 T cells. Formation of platelet-CD4 T cell aggregates involved interaction of CD62P on activated platelets with adhesion molecule CD166 on activated CD4 T cells, contributing to downmodulation of CD4 T cell activation, proliferation and production of IFN-γ. Blocking of formation of platelet-CD4 T cell aggregates during progression of EAE substantially enhanced proliferation of CD4 T cell in the CNS and the periphery leading to exacerbation of the disease. Conclusion Our study indicates differential roles for platelets in the regulation of functions of pathogenic CD4 T cells during initiation and progression of CNS autoimmune inflammation. PMID:26294656

Preserved immune functionality and high CMV-specific T-cell responses in HIV-infected individuals with poor CD4+ T-cell immune recovery.

PubMed

Gómez-Mora, Elisabet; García, Elisabet; Urrea, Victor; Massanella, Marta; Puig, Jordi; Negredo, Eugenia; Clotet, Bonaventura; Blanco, Julià; Cabrera, Cecilia

2017-09-15

Poor CD4 + T-cell recovery after cART has been associated with skewed T-cell maturation, inflammation and immunosenescence; however, T-cell functionality in those individuals has not been fully characterized. In the present study, we assessed T-cell function by assessing cytokine production after polyclonal, CMV and HIV stimulations of T-cells from ART-suppressed HIV-infected individuals with CD4 + T-cell counts >350 cells/μL (immunoconcordants) or <350 cells/μL (immunodiscordants). A group of HIV-uninfected individuals were also included as controls. Since CMV co-infection significantly affected T-cell maturation and polyfunctionality, only CMV + individuals were analyzed. Despite their reduced and skewed CD4 + T-cell compartment, immunodiscordant individuals showed preserved polyclonal and HIV-specific responses. However, CMV response in immunodiscordant participants was significantly different from immunoconcordant or HIV-seronegative individuals. In immunodiscordant subjects, the magnitude of IFN-γ + CD8 + and IL-2 + CD4 + T-cells in response to CMV was higher and differently associated with the CD4 + T-cell maturation profile., showing an increased frequency of naïve, central memory and EMRA CMV-specific CD4 + T-cells. In conclusion, CD4 + and CD8 + T-cell polyfunctionality was not reduced in immunodiscordant individuals, although heightened CMV-specific immune responses, likely related to subclinical CMV reactivations, may be contributing to the skewed T-cell maturation and the higher risk of clinical progression observed in those individuals.

Adoptive transfer of gene-engineered CD4+ helper T cells induces potent primary and secondary tumor rejection.

PubMed

Moeller, Maria; Haynes, Nicole M; Kershaw, Michael H; Jackson, Jacob T; Teng, Michele W L; Street, Shayna E; Cerutti, Loretta; Jane, Stephen M; Trapani, Joseph A; Smyth, Mark J; Darcy, Phillip K

2005-11-01

Because CD4+ T cells play a key role in aiding cellular immune responses, we wanted to assess whether increasing numbers of gene-engineered antigen-restricted CD4+ T cells could enhance an antitumor response mediated by similarly gene-engineered CD8+ T cells. In this study, we have used retroviral transduction to generate erbB2-reactive mouse T-cell populations composed of various proportions of CD4+ and CD8+ cells and then determined the antitumor reactivity of these mixtures. Gene-modified CD4+ and CD8+ T cells were shown to specifically secrete Tc1 (T cytotoxic-1) or Tc2 cytokines, proliferate, and lyse erbB2+ tumor targets following antigen ligation in vitro. In adoptive transfer experiments using severe combined immunodeficient (scid) mice, we demonstrated that injection of equivalent numbers of antigen-specific engineered CD8+ and CD4+ T cells led to significant improvement in survival of mice bearing established lung metastases compared with transfer of unfractionated (largely CD8+) engineered T cells. Transferred CD4+ T cells had to be antigen-specific (not just activated) and secrete interferon gamma (IFN-gamma) to potentiate the antitumor effect. Importantly, antitumor responses in these mice correlated with localization and persistence of gene-engineered T cells at the tumor site. Strikingly, mice that survived primary tumor challenge could reject a subsequent rechallenge. Overall, this study has highlighted the therapeutic potential of using combined transfer of antigen-specific gene-modified CD8+ and CD4+ T cells to significantly enhance T-cell adoptive transfer strategies for cancer therapy.

HIV-1 Antibody Neutralization Breadth Is Associated with Enhanced HIV-Specific CD4+ T Cell Responses

PubMed Central

Soghoian, Damien Z.; Lindqvist, Madelene; Ghebremichael, Musie; Donaghey, Faith; Carrington, Mary; Seaman, Michael S.; Kaufmann, Daniel E.; Walker, Bruce D.

2015-01-01

ABSTRACT Antigen-specific CD4+ T helper cell responses have long been recognized to be a critical component of effective vaccine immunity. CD4+ T cells are necessary to generate and maintain humoral immune responses by providing help to antigen-specific B cells for the production of antibodies. In HIV infection, CD4+ T cells are thought to be necessary for the induction of Env-specific broadly neutralizing antibodies. However, few studies have investigated the role of HIV-specific CD4+ T cells in association with HIV neutralizing antibody activity in vaccination or natural infection settings. Here, we conducted a comprehensive analysis of HIV-specific CD4+ T cell responses in a cohort of 34 untreated HIV-infected controllers matched for viral load, with and without neutralizing antibody breadth to a panel of viral strains. Our results show that the breadth and magnitude of Gag-specific CD4+ T cell responses were significantly higher in individuals with neutralizing antibodies than in those without neutralizing antibodies. The breadth of Gag-specific CD4+ T cell responses was positively correlated with the breadth of neutralizing antibody activity. Furthermore, the breadth and magnitude of gp41-specific, but not gp120-specific, CD4+ T cell responses were significantly elevated in individuals with neutralizing antibodies. Together, these data suggest that robust Gag-specific CD4+ T cells and, to a lesser extent, gp41-specific CD4+ T cells may provide important intermolecular help to Env-specific B cells that promote the generation or maintenance of Env-specific neutralizing antibodies. IMPORTANCE One of the earliest discoveries related to CD4+ T cell function was their provision of help to B cells in the development of antibody responses. Yet little is known about the role of CD4+ T helper responses in the setting of HIV infection, and no studies to date have evaluated the impact of HIV-specific CD4+ T cells on the generation of antibodies that can neutralize multiple different strains of HIV. Here, we addressed this question by analyzing HIV-specific CD4+ T cell responses in untreated HIV-infected persons with and without neutralizing antibodies. Our results indicate that HIV-infected persons with neutralizing antibodies have significantly more robust CD4+ T cell responses targeting Gag and gp41 proteins than individuals who lack neutralizing antibodies. These associations suggest that Gag- and gp41-specific CD4+ T cell responses may provide robust help to B cells for the generation or maintenance of neutralizing antibodies in natural HIV-infection. PMID:26656715

Evaluation of the United States Public Health Service guidelines for discontinuation of anti-CMV therapy after immune recovery in patients with CMV retinitis

PubMed Central

Holbrook, Janet T.; Colvin, Ryan; Van Natta, Mark L.; Thorne, Jennifer E.; Bardsley, Mark; Jabs, Douglas A.

2011-01-01

Purpose To evaluate US Public Health Service (USPHS) guidelines for discontinuing anti-CMV therapy in patients with AIDS who have immune recovery and quiescent retinitis after initiating highly active anti-retroviral therapy (HAART). Design Cohort study of patients with CMV retinitis (Longitudinal Study of Ocular Complications of AIDS). Methods Participants had CMV retinitis and CD4+ T-cell counts of 50 cells/uL or fewer enrolled from 1998 to 2009 who demonstrated sustained immune recovery (two consecutive CD4+ T-cell counts of 100 cells/uL or more at least 6 months apart) and inactive retinitis. Participants were classified into 2 groups according to anti-CMV treatment after immune recover: (1) continued anti-CMV therapy and (2) discontinued therapy. We evaluated survival, visual acuity, and CMV retinitis activity; we employed propensity scores to adjust for confounding factors for these analyses. Results Of 152 participants reviewed, 71 demonstrated immune recovery; 37 of whom discontinued therapy and 34 who continued therapy. At immune recovery, participants continuing therapy tended to be older (44 vs 40 years, P=0.09), have bilateral retinitis (53% vs 32%, P=0.10), and have lower CD4+ T-cell counts (148 vs 207 cells/μL, P<0.001). There were no statistical differences in any of the clinical outcomes (death, retinitis progress, visual acuity or incidence of bilateral retinitis). Both groups lost visual acuity during follow-up, on average 1.2 letters per year (P<0.01). Conclusion Discontinuation of anti-CMV therapy after immune recovery did not increase the risk of poor outcomes. These results support the current guidelines for discontinuation of anti-CMV therapy after achievement of sustained immune recovery. PMID:21742304

Evaluation of the United States public health service guidelines for discontinuation of anticytomegalovirus therapy after immune recovery in patients with cytomegalovirus retinitis.

PubMed

Holbrook, Janet T; Colvin, Ryan; van Natta, Mark L; Thorne, Jennifer E; Bardsley, Mark; Jabs, Douglas A

2011-10-01

To evaluate United States Public Health Service (USPHS) guidelines for discontinuing anticytomegalovirus (CMV) therapy in patients with AIDS who have immune recovery and quiescent retinitis after initiating highly active antiretroviral therapy. Cohort study of patients with CMV retinitis (Longitudinal Study of Ocular Complications of AIDS). Participants had CMV retinitis and CD4+ T-cell counts of 50 cells/μL or fewer enrolled from 1998 through 2009 who demonstrated sustained immune recovery (2 consecutive CD4+ T-cell counts of 100 cells/μL or more at least 6 months apart) and inactive retinitis. Participants were classified into 2 groups according to anti-CMV treatment after immune recover: (1) continued anti-CMV therapy and (2) discontinued therapy. We evaluated survival, visual acuity, and CMV retinitis activity; we used propensity scores to adjust for confounding factors for these analyses. Of 152 participants reviewed, 71 demonstrated immune recovery, 37 of whom discontinued therapy and 34 of whom continued therapy. At immune recovery, participants continuing therapy tended to be older (44 vs 40 years; P = .09), have bilateral retinitis (53% vs 32%; P = .10), and have lower CD4+ T-cell counts (148 vs 207 cells/μL; P < .001). There were no statistical differences in any of the clinical outcomes (death, retinitis progress, visual acuity, or incidence of bilateral retinitis). Both groups lost visual acuity during follow-up, on average 1.2 letters per year (P < .01). Discontinuation of anti-CMV therapy after immune recovery did not increase the risk of poor outcomes. These results support the current guidelines for discontinuation of anti-CMV therapy after achievement of sustained immune recovery. Copyright © 2011 Elsevier Inc. All rights reserved.

CD4+ Primary T Cells Expressing HCV-Core Protein Upregulate Foxp3 and IL-10, Suppressing CD4 and CD8 T Cells

PubMed Central

Aguado, Enrique; Garcia-Cozar, Francisco

2014-01-01

Adaptive T cell responses are critical for controlling HCV infection. While there is clinical evidence of a relevant role for regulatory T cells in chronic HCV-infected patients, based on their increased number and function; mechanisms underlying such a phenomena are still poorly understood. Accumulating evidence suggests that proteins from Hepatitis C virus can suppress host immune responses. We and others have shown that HCV is present in CD4+ lymphocytes from chronically infected patients and that HCV-core protein induces a state of unresponsiveness in the CD4+ tumor cell line Jurkat. Here we show that CD4+ primary T cells lentivirally transduced with HCV-core, not only acquire an anergic phenotype but also inhibit IL-2 production and proliferation of bystander CD4+ or CD8+ T cells in response to anti-CD3 plus anti-CD28 stimulation. Core-transduced CD4+ T cells show a phenotype characterized by an increased basal secretion of the regulatory cytokine IL-10, a decreased IFN-γ production upon stimulation, as well as expression of regulatory T cell markers, CTLA-4, and Foxp3. A significant induction of CD4+CD25+CD127lowPD-1highTIM-3high regulatory T cells with an exhausted phenotype was also observed. Moreover, CCR7 expression decreased in HCV-core expressing CD4+ T cells explaining their sequestration in inflamed tissues such as the infected liver. This work provides a new perspective on de novo generation of regulatory CD4+ T cells in the periphery, induced by the expression of a single viral protein. PMID:24465502

Cell-contact-dependent activation of CD4+ T cells by adhesion molecules on synovial fibroblasts.

PubMed

Mori, Masato; Hashimoto, Motomu; Matsuo, Takashi; Fujii, Takao; Furu, Moritoshi; Ito, Hiromu; Yoshitomi, Hiroyuki; Hirose, Jun; Ito, Yoshinaga; Akizuki, Shuji; Nakashima, Ran; Imura, Yoshitaka; Yukawa, Naoichiro; Yoshifuji, Hajime; Ohmura, Koichiro; Mimori, Tsuneyo

2017-05-01

To determine how cell-cell contact with synovial fibroblasts (SF) influence on the proliferation and cytokine production of CD4 +  T cells. Naïve CD4 +  T cells were cultured with SF from rheumatoid arthritis patients, stimulated by anti-CD3/28 antibody, and CD4 +  T cell proliferation and IFN-γ/IL-17 production were analyzed. To study the role of adhesion molecules, cell contact was blocked by transwell plate or anti-intracellular adhesion molecule-1 (ICAM-1)/vascular cell adhesion molecule-1(VCAM-1) antibody. To study the direct role of adhesion molecules for CD4 +  T cells, CD161 +  or CD161 - naïve CD4 +  T cells were stimulated on plastic plates coated by recombinant ICAM-1 or VCAM-1, and the source of IFN-γ/IL-17 were analyzed. SF enhanced naïve CD4 +  T cell proliferation and IFN-γ/IL-17 production in cell-contact and in part ICAM-1-/VCAM-1-dependent manner. Plate-coated ICAM-1 and VCAM-1 enhanced naïve CD4 +  T cell proliferation and IFN-γ production, while VCAM-1 efficiently promoting IL-17 production. CD161 +  naïve T cells upregulating LFA-1 and VLA-4 were the major source of IFN-γ/IL-17 upon interaction with ICAM-1/VCAM-1. CD4 +  T cells rapidly expand and secrete IFN-γ/IL-17 upon cell-contact with SF via adhesion molecules. Interfering with ICAM-1-/VCAM-1 may be beneficial for inhibiting RA synovitis.

Cytokines affecting CD4+T regulatory cells in transplant tolerance. II. Interferon gamma (IFN-γ) promotes survival of alloantigen-specific CD4+T regulatory cells.

PubMed

Nomura, Masaru; Hodgkinson, Suzanne J; Tran, Giang T; Verma, Nirupama D; Robinson, Catherine; Plain, Karren M; Boyd, Rochelle; Hall, Bruce M

2017-06-01

CD4 + T cells that transfer alloantigen-specific transplant tolerance are short lived in culture unless stimulated with specific-donor alloantigen and lymphocyte derived cytokines. Here, we examined if IFN-γ maintained survival of tolerance transferring CD4 + T cells. Alloantigen-specific transplant tolerance was induced in DA rats with heterotopic adult PVG heart allografts by a short course of immunosuppression and these grafts functioned for >100days with no further immunosuppression. In previous studies, we found the CD4 + T cells from tolerant rats that transfer tolerance to an irradiated DA host grafted with a PVG heart, lose their tolerance transferring ability after 3days of culture, either with or without donor alloantigen, and effect rejection of specific-donor grafts. If cultures with specific-donor alloantigen are supplemented by supernatant from ConA activated lymphocytes the tolerance transferring cells survive, suggesting these cells depend on cytokines for their survival. In this study, we found addition of rIFN-γ to MLC with specific-donor alloantigen maintained the capacity of tolerant CD4 + T cells to transfer alloantigen-specific tolerance and their ability to suppress PVG allograft rejection mediated by co-administered naïve CD4 + T cells. IFN-γ suppressed the in vitro proliferation of tolerant CD4 + T cells. Tolerant CD4 + CD25 + T cells did not proliferate in MLC to PVG stimulator cells with no cytokine added, but did when IFN-γ was present. IFN-γ did not alter proliferation of tolerant CD4 + CD25 + T cells to third-party Lewis. Tolerant CD4 + CD25 + T cells' expression of IFN-γ receptor (IFNGR) was maintained in culture when IFN-γ was present. This study suggested that IFN-γ maintained tolerance mediating alloantigen-specific CD4 + CD25 + T cells. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

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.

CD4+CD25hiFOXP3+ Cells in Cord Blood of Neonates Born from Filaria Infected Mother Are Negatively Associated with CD4+Tbet+ and CD4+RORγt+ T Cells

PubMed Central

Zettlmeissl, Eva; van der Vlugt, Luciën E. P. M.; de Jong, Sanne; Matsiegui, Pierre-Blaise; Ramharter, Michael; Kremsner, Peter G.; Yazdanbakhsh, Maria; Adegnika, Ayola Akim

2014-01-01

Background Children who have been exposed in utero to maternal filarial infection are immunologically less responsive to filarial antigens, have less pathology, and are more susceptible to acquire infection than offspring of uninfected mothers. Moreover children from filaria infected mothers have been shown to be less responsive to vaccination as a consequence of an impairment of their immune response. However, it is not well known how in utero exposure to parasite antigens affects cellular immune responses. Methodology Here, 30 pregnant women were examined for the presence of microfilaria of Loa loa and Mansonella perstans in peripheral blood. At delivery, cord blood mononuclear cells (CBMC) were obtained and the CD4+T cells were phenotyped by expression of the transcription factors Tbet, RORγt, and FOXP3. Results No significant difference was observed between newborns from infected versus uninfected mothers in the frequencies of total CD4+T cells and CD4+T cells subsets including CD4+Tbet+, CD4+RORγt+ T and CD4+CD25hiFOXP3+ T cells. However, there was a negative association between CD4+CD25hiFOXP3+T cells and CD4+Tbet+ as well as CD4+RORγt+ T cells in the infected group only (B = −0.242, P = 0.002; B = −0.178, P = 0.013 respectively). Conclusion Our results suggest that filarial infection during pregnancy leads to an expansion of functionally active regulatory T cells that keep TH1 and TH17 in check. PMID:25531674

CD4 on CD8+ T cells directly enhances effector function and is a target for HIV infection

NASA Astrophysics Data System (ADS)

Kitchen, Scott G.; Jones, Nicole R.; Laforge, Stuart; Whitmire, Jason K.; Vu, Bien-Aimee; Galic, Zoran; Brooks, David G.; Brown, Stephen J.; Kitchen, Christina M. R.; Zack, Jerome A.

2004-06-01

Costimulation of purified CD8+ T lymphocytes induces de novo expression of CD4, suggesting a previously unrecognized function for this molecule in the immune response. Here, we report that the CD4 molecule plays a direct role in CD8+ T cell function by modulating expression of IFN- and Fas ligand, two important CD8+ T cell effector molecules. CD4 expression also allows infection of CD8 cells by HIV, which results in down-regulation of the CD4 molecule and impairs the induction of IFN-, Fas ligand, and the cytotoxic responses of activated CD8+ T cells. Thus, the CD4 molecule plays a direct role in CD8 T cell function, and infection of these cells by HIV provides an additional reservoir for the virus and also may contribute to the immunodeficiency seen in HIV disease.

Characterisation of an epigenetically altered CD4+ CD28+ Kir+ T cell subset in autoimmune rheumatic diseases by multiparameter flow cytometry

PubMed Central

Strickland, Faith M; Patel, Dipak; Somers, Emily; Robida, Aaron M; Pihalja, Michael; Swartz, Richard; Marder, Wendy; Richardson, Bruce

2016-01-01

Objectives Antigen-specific CD4+ T cells epigenetically modified with DNA methylation inhibitors overexpress genes normally suppressed by this mechanism, including CD11a, CD70, CD40L and the KIR gene family. The altered cells become autoreactive, losing restriction for nominal antigen and responding to self-class II major histocompatibility complex (MHC) molecules without added antigen, and are sufficient to cause a lupus-like disease in syngeneic mice. T cells overexpressing the same genes are found in patients with active lupus. Whether these genes are co-overexpressed on the same or different cells is unknown. The goal of this study was to determine whether these genes are overexpressed on the same or different T cells and whether this subset of CD4+ T cells is also present in patients with lupus and other rheumatic diseases. Methods Multicolour flow cytometry was used to compare CD11a, CD70, CD40L and KIR expression on CD3+CD4+CD28+ T cells to their expression on experimentally demethylated CD3+CD4+CD28+ T cells and CD3+CD4+CD28+ T cells from patients with active lupus and other autoimmune diseases. Results Experimentally demethylated CD4+ T cells and T cells from patients with active lupus have a CD3+CD4+CD28+CD11ahiCD70+CD40LhiKIR+ subset, and the subset size is proportional to lupus flare severity. A similar subset is found in patients with other rheumatic diseases including rheumatoid arthritis, systemic sclerosis and Sjögren's syndrome but not retroperitoneal fibrosis. Conclusions Patients with active autoimmune rheumatic diseases have a previously undescribed CD3+CD4+CD28+CD11ahiCD70+CD40LhiKIR+ T cell subset. This subset may play an important role in flares of lupus and related autoimmune rheumatic diseases, provide a biomarker for disease activity and serve as a novel therapeutic target for the treatment of lupus flares. PMID:27099767

Task-shifting of CD4 T cell count monitoring by the touchscreen-based Muse™ Auto CD4/CD4% single-platform system for CD4 T cell numeration: Implication for decentralization in resource-constrained settings.

PubMed

Kouabosso, André; Mossoro-Kpinde, Christian Diamant; Bouassa, Ralph-Sydney Mboumba; Longo, Jean De Dieu; Mbeko Simaleko, Marcel; Grésenguet, Gérard; Bélec, Laurent

2018-04-01

The accuracy of CD4 T cell monitoring by the recently developed flow cytometry-based CD4 T cell counting Muse™ Auto CD4/CD4% Assay analyzer (EMD Millipore Corporation, Merck Life Sciences, KGaA, Darmstadt, Germany) was evaluated in trained lay providers against laboratory technicians. After 2 days of training on the Muse™ Auto CD4/CD4% analyzer, EDTA-blood samples from 6 HIV-positive and 4 HIV-negative individuals were used for CD4 T cell counting in triplicate in parallel by 12 trained lay providers as compared to 10 lab technicians. Mean number of CD4 T cells in absolute number was 829 ± 380 cells/μl by lay providers and 794 ± 409 cells/μl by technicians (P > 0.05); and in percentage 36.2 ± 14.8%CD4 by lay providers and 36.1 ± 15.0%CD4 by laboratory technician (P > 0.05). The unweighted linear regression and Passing-Bablok regression analyses on CD4 T cell results expressed in absolute count revealed moderate correlation between CD4 T cell counts obtained by lay providers and lab technicians. The mean absolute bias measured by Bland-Altman analysis between CD4 T cell/μl obtained by lay providers and lab technicians was -3.41 cells/μl. Intra-assay coefficient of variance (CV) of Muse™ Auto CD4/CD4% in absolute number was 10.1% by lay providers and 8.5% by lab technicians (P > 0.05), and in percentage 5.5% by lay providers and 4.4% by lab technicians (P > 0.05). The inter-assay CV of Muse™ Auto CD4/CD4% in absolute number was 13.4% by lay providers and 10.3% by lab technicians (P > 0.05), and in percentage 7.8% by lay providers and 6.9% by lab technicians (P > 0.05). The study demonstrates the feasibility of CD4 T cell counting using the alternative flow cytometer Muse™ Auto CD4/CD4% analyzer by trained lay providers and therefore the practical possibility of decentralization CD4 T cell counting to health community centers. Copyright © 2018. Published by Elsevier B.V.

The Majority of HIV Type 1 DNA in Circulating CD4+ T Lymphocytes Is Present in Non-Gut-Homing Resting Memory CD4+ T Cells

PubMed Central

Xu, Yin; Bailey, Michelle; Seddiki, Nabila; Suzuki, Kazuo; Murray, John M.; Gao, Yuan; Yan, Celine; Cooper, David A.; Kelleher, Anthony D.; Koelsch, Kersten K.; Zaunders, John

2013-01-01

Abstract Memory CD4+ T lymphocytes in peripheral blood that express integrins α4ß7 preferentially recirculate through gut-associated lymphoid tissue (GALT), a proposed site of significant HIV-1 replication. Tregs and activated CD4+ T cells in GALT could also be particularly susceptible to infection. We therefore hypothesized that infection of these subsets of memory CD4+ T cells may contribute disproportionately to the HIV-1 reservoir. A cross-sectional study of CD4+ T cell subsets of memory CD45RO+ cells in peripheral blood mononuclear cells (PBMCs) was conducted using leukapheresis from eight subjects with untreated chronic HIV-1 infection. Real-time polymerase chain reaction (PCR) was used to quantify total and integrated HIV-1 DNA levels from memory CD4+ T cells sorted into integrin β7+ vs. β7−, CD25+CD127low Treg vs. CD127high, and activated CD38+ vs. CD38−. More than 80% of total HIV-1 DNA was found to reside in the integrin β7-negative non-gut-homing subset of CD45RO+ memory CD4+ T cells. Less than 10% was found in highly purified Tregs or CD38+ activated memory cells. Similarly, integrated HIV-1 DNA copies were found to be more abundant in resting non-gut-homing memory CD4+ T cells (76%) than in their activated counterparts (23%). Our investigations showed that the majority of both total and integrated HIV-1 DNA was found within non-gut-homing resting CD4+ T cells. PMID:23971972

Phenotypically non-suppressive cells predominate among FoxP3-positive cells in oral lichen planus.

PubMed

Schreurs, Olav; Karatsaidis, Andreas; Schenck, Karl

2016-11-01

Oral lichen planus (OLP) is a common T-cell-dominated oral chronic inflammatory disease occurring in periods of remission, quiescence, activity with pronounced inflammation, and acute ulceration. Cell infiltrates in OLP contain varying numbers of CD4 + T cells expressing the transcription factor FoxP3. FoxP3 + CD4 + T cells are, however, a heterogeneous cell population containing suppressive and non-suppressive cells, and their distribution in infiltrates from OLP is unknown. Biopsies were taken from normal oral mucosa (n = 8) and OLP lesions (n = 19), and a set of in situ methods for the determination of the functional phenotype of FoxP3 + CD4 + T cells was applied. Numbers of FoxP3 + CD4 + T cells were highest in the atrophic form of the disease, yet low in the ulcerative form. The main FoxP3 + CD4 + T-cell population observed was FoxP3 + CD45RA - CD25 + CD45RO + and CD15s - , a phenotype delineating a non-suppressive subset. Numbers of cells with an actively suppressing phenotype (FoxP3 + CD45RA - CD25 + CD45RO + and CD15s + ) were, however, about twice as high in reticular lesions as compared with the atrophic form. Many FoxP3 + CD4 + T cells expressed T-bet, the hallmark transcription factor for IFN-γ-producing T cells, indicating that they may enhance immune and inflammatory responses rather than suppress them. The absence of actively suppressing FoxP3 + CD4 + T cells may in part explain why OLP is a remarkably persisting condition, in spite of the presence of substantially high numbers of FoxP3 + CD4 + T cells. The findings emphasize that it is crucial to examine not only numbers but also functional phenotype of FoxP3 + CD4 + T cells in human tissues. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The primary immune response to Vaccinia virus vaccination includes cells with a distinct cytotoxic effector CD4 T-cell phenotype.

PubMed

Munier, C Mee Ling; van Bockel, David; Bailey, Michelle; Ip, Susanna; Xu, Yin; Alcantara, Sheilajen; Liu, Sue Min; Denyer, Gareth; Kaplan, Warren; Suzuki, Kazuo; Croft, Nathan; Purcell, Anthony; Tscharke, David; Cooper, David A; Kent, Stephen J; Zaunders, John J; Kelleher, Anthony D

2016-10-17

Smallpox was eradicated by a global program of inoculation with Vaccinia virus (VV). Robust VV-specific CD4 T-cell responses during primary infection are likely essential to controlling VV replication. Although there is increasing interest in cytolytic CD4 T-cells across many viral infections, the importance of these cells during acute VV infection is unclear. We undertook a detailed functional and genetic characterization of CD4 T-cells during acute VV-infection of humans. VV-specific T-cells were identified by up-regulation of activation markers directly ex vivo and through cytokine and co-stimulatory molecule expression. At day-13-post primary inoculation with VV, CD38highCD45RO+ CD4 T-cells were purified by cell sorting, RNA isolated and analysed by microarray. Differential expression of up-regulated genes in activated CD4 T-cells was confirmed at the mRNA and protein levels. We compared analyses of VV-specific CD4 T-cells to studies on 12 subjects with primary HIV infection (PHI). VV-specific T-cells lines were established from PBMCs collected post vaccination and checked for cytotoxicity potential. A median 11.9% CD4 T-cells were CD38highCD45RO+ at day-13 post-VV inoculation, compared to 3.0% prior and 10.4% during PHI. Activated CD4 T-cells had an up-regulation of genes related to cytolytic function, including granzymes K and A, perforin, granulysin, TIA-1, and Rab27a. No difference was seen between CD4 T-cell expression of perforin or TIA-1 to VV and PHI, however granzyme k was more dominant in the VV response. At 25:1 effector to target ratio, two VV-specific T-cell lines exhibited 62% and 30% cytotoxicity respectively and CD107a degranulation. We show for the first time that CD4 CTL are prominent in the early response to VV. Understanding the role of CD4 CTL in the generation of an effective anti-viral memory may help develop more effective vaccines for diseases such as HIV. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Antiretroviral therapy suppressed participants with low CD4+ T-cell counts segregate according to opposite immunological phenotypes

PubMed Central

Pérez-Santiago, Josué; Ouchi, Dan; Urrea, Victor; Carrillo, Jorge; Cabrera, Cecilia; Villà-Freixa, Jordi; Puig, Jordi; Paredes, Roger; Negredo, Eugènia; Clotet, Bonaventura; Massanella, Marta; Blanco, Julià

2016-01-01

Background: The failure to increase CD4+ T-cell counts in some antiretroviral therapy suppressed participants (immunodiscordance) has been related to perturbed CD4+ T-cell homeostasis and impacts clinical evolution. Methods: We evaluated different definitions of immunodiscordance based on CD4+ T-cell counts (cutoff) or CD4+ T-cell increases from nadir value (ΔCD4) using supervised random forest classification of 74 immunological and clinical variables from 196 antiretroviral therapy suppressed individuals. Unsupervised clustering was performed using relevant variables identified in the supervised approach from 191 individuals. Results: Cutoff definition of CD4+ cell count 400 cells/μl performed better than any other definition in segregating immunoconcordant and immunodiscordant individuals (85% accuracy), using markers of activation, nadir and death of CD4+ T cells. Unsupervised clustering of relevant variables using this definition revealed large heterogeneity between immunodiscordant individuals and segregated participants into three distinct subgroups with distinct production, programmed cell-death protein-1 (PD-1) expression, activation and death of T cells. Surprisingly, a nonnegligible number of immunodiscordant participants (22%) showed high frequency of recent thymic emigrants and low CD4+ T-cell activation and death, very similar to immunoconcordant participants. Notably, human leukocyte antigen - antigen D related (HLA-DR) PD-1 and CD45RA expression in CD4+ T cells allowed reproducing subgroup segregation (81.4% accuracy). Despite sharp immunological differences, similar and persistently low CD4+ values were maintained in these participants over time. Conclusion: A cutoff value of CD4+ T-cell count 400 cells/μl classified better immunodiscordant and immunoconcordant individuals than any ΔCD4 classification. Immunodiscordance may present several, even opposite, immunological patterns that are identified by a simple immunological follow-up. Subgroup classification may help clinicians to delineate diverse approaches that may be needed to boost CD4+ T-cell recovery. PMID:27427875

FOXP3, CBLB and ITCH gene expression and cytotoxic T lymphocyte antigen 4 expression on CD4+CD25high T cells in multiple sclerosis

PubMed Central

Sellebjerg, F; Krakauer, M; Khademi, M; Olsson, T; Sørensen, P S

2012-01-01

Expression of the forkhead box protein 3 (FoxP3) transcription factor is regulated by the E3 ubiquitin ligases Itch and Cbl-b and induces regulatory activity CD4+CD25high T cells. Treatment with interferon (IFN)-β enhances regulatory T cell activity in multiple sclerosis (MS). We studied the phenotype of CD4+CD25high T cells in MS by flow cytometry and its relationship with expression of the FOXP3, ITCH and CBLB genes. We found that untreated MS patients had lower cell surface expression of cytotoxic T lymphocyte antigen 4 (CTLA-4) on CD4+CD25high T cells and higher intracellular CTLA-4 expression than healthy controls. Cell surface expression of CTLA-4 on CD4+CD25high T cells correlated with expression of FOXP3 mRNA in untreated patients and increased significantly with time from most recent injection in patients treated with IFN-β. FOXP3 mRNA expression correlated with CBLB and ITCH and T helper type 2 cytokine mRNA expression in MS patients. These data link expression of FOXP3, CBLB and ITCH mRNA and CTLA-4 expression on the surface of CD4+CD25high T cell in MS. We hypothesize that this may reflect alterations in the inhibitory effect of CTLA-4 or in regulatory T cell function. PMID:23039885

A correlative and quantitative imaging approach enabling characterization of primary cell-cell communication: Case of human CD4+ T cell-macrophage immunological synapses.

PubMed

Kasprowicz, Richard; Rand, Emma; O'Toole, Peter J; Signoret, Nathalie

2018-05-22

Cell-to-cell communication engages signaling and spatiotemporal reorganization events driven by highly context-dependent and dynamic intercellular interactions, which are difficult to capture within heterogeneous primary cell cultures. Here, we present a straightforward correlative imaging approach utilizing commonly available instrumentation to sample large numbers of cell-cell interaction events, allowing qualitative and quantitative characterization of rare functioning cell-conjugates based on calcium signals. We applied this approach to examine a previously uncharacterized immunological synapse, investigating autologous human blood CD4 + T cells and monocyte-derived macrophages (MDMs) forming functional conjugates in vitro. Populations of signaling conjugates were visualized, tracked and analyzed by combining live imaging, calcium recording and multivariate statistical analysis. Correlative immunofluorescence was added to quantify endogenous molecular recruitments at the cell-cell junction. By analyzing a large number of rare conjugates, we were able to define calcium signatures associated with different states of CD4 + T cell-MDM interactions. Quantitative image analysis of immunostained conjugates detected the propensity of endogenous T cell surface markers and intracellular organelles to polarize towards cell-cell junctions with high and sustained calcium signaling profiles, hence defining immunological synapses. Overall, we developed a broadly applicable approach enabling detailed single cell- and population-based investigations of rare cell-cell communication events with primary cells.

Direct anti-inflammatory effects of granulocyte colony-stimulating factor (G-CSF) on activation and functional properties of human T cell subpopulations in vitro.

PubMed

Malashchenko, Vladimir Vladimirovich; Meniailo, Maxsim Evgenievich; Shmarov, Viacheslav Anatolievich; Gazatova, Natalia Dinislamovna; Melashchenko, Olga Borisovna; Goncharov, Andrei Gennadievich; Seledtsova, Galina Victorovna; Seledtsov, Victor Ivanovich

2018-03-01

We investigated the direct effects of human granulocyte colony-stimulating factor (G-CSF) on functionality of human T-cell subsets. CD3 + T-lymphocytes were isolated from blood of healthy donors by positive magnetic separation. T cell activation with particles conjugated with antibodies (Abs) to human CD3, CD28 and CD2 molecules increased the proportion of cells expressing G-CSF receptor (G-CSFR, CD114) in all T cell subpopulations studied (CD45RA + /CD197 + naive T cells, CD45RA - /CD197 + central memory T cells, CD45RA - /CD197 - effector memory T cells and CD45RA + /CD197 - terminally differentiated effector T cells). Upon T-cell activation in vitro, G-CSF (10.0 ng/ml) significantly and specifically enhanced the proportion of CD114 + T cells in central memory CD4 + T cell compartment. A dilution series of G-CSF (range, 0.1-10.0 ng/ml) was tested, with no effect on the expression of CD25 (interleukin-2 receptor α-chain) on activated T cells. Meanwhile, G-CSF treatment enhanced the proportion of CD38 + T cells in CD4 + naïve T cell, effector memory T cell and terminally differentiated effector T cell subsets, as well as in CD4 - central memory T cells and terminally differentiated effector T cells. G-CSF did not affect IL-2 production by T cells; relatively low concentrations of G-CSF down-regulated INF-γ production, while high concentrations of this cytokine up-regulated IL-4 production in activated T cells. The data obtained suggests that G-CSF could play a significant role both in preventing the development of excessive and potentially damaging inflammatory reactivity, and in constraining the expansion of potentially cytodestructive T cells. Copyright © 2018 Elsevier Inc. All rights reserved.

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.

Engagement of Cytotoxic T Lymphocyte–associated Antigen 4 (CTLA-4) Induces Transforming Growth Factor β (TGF-β) Production by Murine CD4+ T Cells

PubMed Central

Chen, Wanjun; Jin, Wenwen; Wahl, Sharon M.

1998-01-01

Evidence indicates that cytotoxic T lymphocyte–associated antigen 4 (CTLA-4) may negatively regulate T cell activation, but the basis for the inhibitory effect remains unknown. We report here that cross-linking of CTLA-4 induces transforming growth factor β (TGF-β) production by murine CD4+ T cells. CD4+ T helper type 1 (Th1), Th2, and Th0 clones all secrete TGF-β after antibody cross-linking of CTLA-4, indicating that induction of TGF-β by CTLA-4 signaling represents a ubiquitous feature of murine CD4+ T cells. Stimulation of the CD3–T cell antigen receptor complex does not independently induce TGF-β, but is required for optimal CTLA-4–mediated TGF-β production. The consequences of cross-linking of CTLA-4, together with CD3 and CD28, include inhibition of T cell proliferation and interleukin (IL)-2 secretion, as well as suppression of both interferon γ (Th1) and IL-4 (Th2). Moreover, addition of anti–TGF-β partially reverses this T cell suppression. When CTLA-4 was cross-linked in T cell populations from TGF-β1 gene–deleted (TGF-β1−/−) mice, the T cell responses were only suppressed 38% compared with 95% in wild-type mice. Our data demonstrate that engagement of CTLA-4 leads to CD4+ T cell production of TGF-β, which, in part, contributes to the downregulation of T cell activation. CTLA-4, through TGF-β, may serve as a counterbalance for CD28 costimulation of IL-2 and CD4+ T cell activation. PMID:9815262

In situ targeting of dendritic cells sets tolerogenic environment and ameliorates CD4+ T-cell response in the postischemic liver.

PubMed

Funken, Dominik; Ishikawa-Ankerhold, Hellen; Uhl, Bernd; Lerchenberger, Maximilian; Rentsch, Markus; Mayr, Doris; Massberg, Steffen; Werner, Jens; Khandoga, Andrej

2017-11-01

CD4 + T cells recruited to the liver play a key role in the pathogenesis of ischemia/reperfusion (I/R) injury. The mechanism of their activation during alloantigen-independent I/R is not completely understood. We hypothesized that liver-resident dendritic cells (DCs) interact with CD4 + T cells in the postischemic liver and that modulation of DCs or T-cell-DC interactions attenuates liver inflammation. In mice, warm hepatic I/R (90/120-240 min) was induced. Tolerogenic DCs were generated in situ by pretreatment of animals with the vitamin D analog paricalcitol. A mAb-CD44 was used for blockade of CD4 + T-cell-DC interactions. As shown by 2-photon in vivo microscopy as well as confocal microscopy, CD4 + T cells were closely colocalized with DCs in the postischemic liver. Pretreatment with paricalcitol attenuated I/R-induced maturation of DCs (flow cytometry), CD4 + T-cell recruitment into the liver (intravital microscopy), and hepatocellular/microvascular damage (intravital microscopy, alanine aminotransferase/aspartate aminotransferase, histology). However, interruption of T-cell-DC interaction increased proinflammatory DC maturation and even enhanced tissue damage. Simultaneous treatment with an anti-CD44mAb completely abolished the beneficial effect of paricalcitol on T-cell migration and tissue injury. Our study demonstrates for the first time that hepatic DCs interact with CD4 + T cells in the postischemic liver in vivo ; modulation of DCs and/or generation of tolerogenic DCs attenuates intrahepatic CD4 + T-cell recruitment and reduces I/R injury; and interruption of CD44-dependent CD4 + T-cell-DC interactions enhances tissue injury by preventing the modulatory effect of hepatic DCs on T cells, especially type 1 T helper effector cells. Thus, hepatic DCs are strongly involved in the promotion of CD4 + T-cell-dependent postischemic liver inflammation.-Funken, D., Ishikawa-Ankerhold, H., Uhl, B., Lerchenberger, M., Rentsch, M., Mayr, D., Massberg, S., Werner, J., Khandoga, A. In situ targeting of dendritic cells sets tolerogenic environment and ameliorates CD4 + T-cell response in the postischemic liver. © FASEB.

How Do CD4+ T Cells Detect and Eliminate Tumor Cells That Either Lack or Express MHC Class II Molecules?

PubMed Central

Haabeth, Ole Audun Werner; Tveita, Anders Aune; Fauskanger, Marte; Schjesvold, Fredrik; Lorvik, Kristina Berg; Hofgaard, Peter O.; Omholt, Hilde; Munthe, Ludvig A.; Dembic, Zlatko; Corthay, Alexandre; Bogen, Bjarne

2014-01-01

CD4+ T cells contribute to tumor eradication, even in the absence of CD8+ T cells. Cytotoxic CD4+ T cells can directly kill MHC class II positive tumor cells. More surprisingly, CD4+ T cells can indirectly eliminate tumor cells that lack MHC class II expression. Here, we review the mechanisms of direct and indirect CD4+ T cell-mediated elimination of tumor cells. An emphasis is put on T cell receptor (TCR) transgenic models, where anti-tumor responses of naïve CD4+ T cells of defined specificity can be tracked. Some generalizations can tentatively be made. For both MHCIIPOS and MHCIINEG tumors, presentation of tumor-specific antigen by host antigen-presenting cells (APCs) appears to be required for CD4+ T cell priming. This has been extensively studied in a myeloma model (MOPC315), where host APCs in tumor-draining lymph nodes are primed with secreted tumor antigen. Upon antigen recognition, naïve CD4+ T cells differentiate into Th1 cells and migrate to the tumor. At the tumor site, the mechanisms for elimination of MHCIIPOS and MHCIINEG tumor cells differ. In a TCR-transgenic B16 melanoma model, MHCIIPOS melanoma cells are directly killed by cytotoxic CD4+ T cells in a perforin/granzyme B-dependent manner. By contrast, MHCIINEG myeloma cells are killed by IFN-γ stimulated M1-like macrophages. In summary, while the priming phase of CD4+ T cells appears similar for MHCIIPOS and MHCIINEG tumors, the killing mechanisms are different. Unresolved issues and directions for future research are addressed. PMID:24782871

Site-specific differences in T cell frequencies and phenotypes in the blood and gut of HIV-uninfected and ART-treated HIV+ adults.

PubMed

Yukl, Steven A; Shergill, Amandeep K; Girling, Valerie; Li, Qingsheng; Killian, Maudi; Epling, Lorrie; Li, Peilin; Kaiser, Philipp; Haase, Ashley; Havlir, Diane V; McQuaid, Kenneth; Sinclair, Elizabeth; Wong, Joseph K

2015-01-01

Gastrointestinal T lymphocytes are critical for mucosal immunity and HIV pathogenesis, yet little is known about normal T cell numbers and phenotypes in different regions of the gut, or the degree to which ART can restore levels to those of HIV-uninfected individuals. To investigate these questions, we measured T cell frequencies and markers of memory, activation, anergy, and homing in the blood, ileum, and rectum of HIV- and ART-suppressed HIV+ adults. In HIV- individuals, T cell frequencies and phenotypes differed significantly between sites. Compared to HIV- adults, HIV+ adults had lower absolute CD4+T cell counts in the ileal lamina propria and lower relative CD4+T cell counts in the blood and ileum. In the gut, HIV+ adults had a higher proportion of CD38+ CD4+T cells, a lower proportion of terminally-differentiated effector cells, and, in the rectum, a higher proportion of CTLA-4+ CD4+T cells. In HIV+ individuals, relative CD4+T cell numbers in the ileum correlated with the proportion of CTLA-4+ CD4+T cells, whereas in the rectum, they tended to correlate with the proportion of circulating CD4+T cells expressing α4β7 or CCR6. Mechanisms of T cell reconstitution may differ throughout the gut, with homing contributing more in the rectum while ileal reconstitution is associated with mucosal CD4+T cell anergy.

Regulatory function of cytomegalovirus-specific CD4{sup +}CD27{sup -}CD28{sup -} T cells

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

Tovar-Salazar, Adriana; Patterson-Bartlett, Julie; Jesser, Renee

2010-03-15

CMV infection is characterized by high of frequencies of CD27{sup -}CD28{sup -} T cells. Here we demonstrate that CMV-specific CD4{sup +}CD27{sup -}CD28{sup -} cells are regulatory T cells (T{sub R}). CD4{sup +}CD27{sup -}CD28{sup -} cells sorted from CMV-stimulated PBMC of CMV-seropositive donors inhibited de novo CMV-specific proliferation of autologous PBMC in a dose-dependent fashion. Compared with the entire CMV-stimulated CD4{sup +} T-cell population, higher proportions of CD4{sup +}CD27{sup -}CD28{sup -} T{sub R} expressed FoxP3, TGFbeta, granzyme B, perforin, GITR and PD-1, lower proportions expressed CD127 and PD1-L and similar proportions expressed CD25, CTLA4, Fas-L and GITR-L. CMV-CD4{sup +}CD27{sup -}CD28{sup -}more » T{sub R} expanded in response to IL-2, but not to CMV antigenic restimulation. The anti-proliferative effect of CMV-CD4{sup +}CD27{sup -}CD28{sup -} T{sub R} significantly decreased after granzyme B or TGFbeta inhibition. The CMV-CD4{sup +}CD27{sup -}CD28{sup -} T{sub R} of HIV-infected and uninfected donors had similar phenotypes and anti-proliferative potency, but HIV-infected individuals had higher proportions of CMV-CD4{sup +}CD27{sup -}CD28{sup -} T{sub R}. The CMV-CD4{sup +}CD27{sup -}CD28{sup -} T{sub R} may contribute to the downregulation of CMV-specific and nonspecific immune responses of CMV-infected individuals.« less

A subset of virus-specific CD161+ T cells selectively express the multidrug transporter MDR1 and are resistant to chemotherapy in AML

PubMed Central

Alsuliman, Abdullah; Muftuoglu, Muharrem; Khoder, Ahmad; Ahn, Yong-Oon; Basar, Rafet; Verneris, Michael R.; Muranski, Pawel; Barrett, A. John; Liu, Enli; Li, Li; Stringaris, Kate; Armstrong-James, Darius; Shaim, Hila; Kondo, Kayo; Imahashi, Nobuhiko; Andersson, Borje; Marin, David; Champlin, Richard E.; Shpall, Elizabeth J.

2017-01-01

The establishment of long-lived pathogen-specific T cells is a fundamental property of the adaptive immune response. However, the mechanisms underlying long-term persistence of antigen-specific CD4+ T cells are not well-defined. Here we identify a subset of memory CD4+ T cells capable of effluxing cellular toxins, including rhodamine (Rho), through the multidrug efflux protein MDR1 (also known as P-glycoprotein and ABCB1). Drug-effluxing CD4+ T cells were characterized as CD161+CD95+CD45RA−CD127hiCD28+CD25int cells with a distinct chemokine profile and a Th1-polarized pro-inflammatory phenotype. CD4+CD161+Rho-effluxing T cells proliferated vigorously in response to stimulation with anti-CD3/CD28 beads and gave rise to CD161− progeny in vitro. These cells were also capable of self-renewal and maintained their phenotypic and functional characteristics when cultured with homeostatic cytokines. Multidrug-effluxing CD4+CD161+ T cells were enriched within the viral-specific Th1 repertoire of healthy donors and patients with acute myeloid leukemia (AML) and survived exposure to daunorubicin chemotherapy in vitro. Multidrug-effluxing CD4+CD161+ T cells also resisted chemotherapy-induced cytotoxicity in vivo and underwent significant expansion in AML patients rendered lymphopenic after chemotherapy, contributing to the repopulation of anti-CMV immunity. Finally, after influenza vaccination, the proportion of influenza-specific CD4+ T cells coexpressing CD161 was significantly higher after 2 years compared with 4 weeks after immunization, suggesting CD161 is a marker for long-lived antigen-specific memory T cells. These findings suggest that CD4+CD161+ T cells with rapid efflux capacity contribute to the maintenance of viral-specific memory T cells. These data provide novel insights into mechanisms that preserve antiviral immunity in patients undergoing chemotherapy and have implications for the development of novel immunotherapeutic approaches. PMID:27821506

Identity and Diversity of Human Peripheral Th and T Regulatory Cells Defined by Single-Cell Mass Cytometry.

PubMed

Kunicki, Matthew A; Amaya Hernandez, Laura C; Davis, Kara L; Bacchetta, Rosa; Roncarolo, Maria-Grazia

2018-01-01

Human CD3 + CD4 + Th cells, FOXP3 + T regulatory (Treg) cells, and T regulatory type 1 (Tr1) cells are essential for ensuring peripheral immune response and tolerance, but the diversity of Th, Treg, and Tr1 cell subsets has not been fully characterized. Independent functional characterization of human Th1, Th2, Th17, T follicular helper (Tfh), Treg, and Tr1 cells has helped to define unique surface molecules, transcription factors, and signaling profiles for each subset. However, the adequacy of these markers to recapitulate the whole CD3 + CD4 + T cell compartment remains questionable. In this study, we examined CD3 + CD4 + T cell populations by single-cell mass cytometry. We characterize the CD3 + CD4 + Th, Treg, and Tr1 cell populations simultaneously across 23 memory T cell-associated surface and intracellular molecules. High-dimensional analysis identified several new subsets, in addition to the already defined CD3 + CD4 + Th, Treg, and Tr1 cell populations, for a total of 11 Th cell, 4 Treg, and 1 Tr1 cell subsets. Some of these subsets share markers previously thought to be selective for Treg, Th1, Th2, Th17, and Tfh cells, including CD194 (CCR4) + FOXP3 + Treg and CD183 (CXCR3) + T-bet + Th17 cell subsets. Unsupervised clustering displayed a phenotypic organization of CD3 + CD4 + T cells that confirmed their diversity but showed interrelation between the different subsets, including similarity between Th1-Th2-Tfh cell populations and Th17 cells, as well as similarity of Th2 cells with Treg cells. In conclusion, the use of single-cell mass cytometry provides a systems-level characterization of CD3 + CD4 + T cells in healthy human blood, which represents an important baseline reference to investigate abnormalities of different subsets in immune-mediated pathologies. Copyright © 2017 by The American Association of Immunologists, Inc.

Role for granulocyte colony-stimulating factor in the generation of human T regulatory type 1 cells.

PubMed

Rutella, Sergio; Pierelli, Luca; Bonanno, Giuseppina; Sica, Simona; Ameglio, Franco; Capoluongo, Ettore; Mariotti, Andrea; Scambia, Giovanni; d'Onofrio, Giuseppe; Leone, Giuseppe

2002-10-01

Granulocyte colony-stimulating factor (G-CSF) may affect T-cell homeostasis by multiple mechanisms, inducing polarization of cytokine secretion, inhibition of T-cell proliferation, and enhancement of T-cell apoptosis. We analyzed the production of interleukin-10 (IL-10) and transforming growth factor-beta1 (TGF-beta1) by T cells from healthy volunteer donors treated with recombinant human G-CSF. Highly purified CD4(+) T cells obtained before and after G-CSF administration (pre-G and post-G, respectively) were activated using the allogeneic mixed leukocyte reaction. Post-G CD4(+) T cells produced high levels of IL-10 but undetectable levels of IL-2 and IL-4, whereas the level of TGF-beta1 release was comparable to that of pre-G CD4(+) T cells. Notably, post-G CD4(+) T cells proliferated poorly in response to alloantigens and to recall antigens and suppressed the proliferation of autologous CD4(+) T cells in a cell contact-independent and an antigen-nonspecific manner. TGF-beta1 and IL-10 were not dispensable for post-G CD4(+) T cells to mediate suppression, as shown by neutralization studies. Compared with pre-G CD4(+) T cells, alloantigen-activated post-G CD4(+) T cells preferentially expressed markers associated with memory T cells, in conjunction with reduced levels of CD28 and CD62L. Collectively, these data demonstrate that CD4(+) T cells exposed to G-CSF in vivo acquire the properties of T regulatory (Tr) cells once triggered in vitro through the T-cell receptor, including a peculiar cytokine production profile (IL-10(++)TGF-beta1(+)IL-2(low/-)IL-4(low/-)), an intrinsic low proliferative capacity, and a contact-independent suppression of antigen-driven proliferation. Tr cells generated ex vivo after exposure to G-CSF might be clinically relevant for transplantation medicine and for the treatment of human immune-mediated diseases.

Crystal structure of a complete ternary complex of T-cell receptor, peptide-MHC, and CD4

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

Yin, Yiyuan; Wang, Xin Xiang; Mariuzza, Roy A

2012-07-11

Adaptive immunity depends on specific recognition by a T-cell receptor (TCR) of an antigenic peptide bound to a major histocompatibility complex (pMHC) molecule on an antigen-presenting cell (APC). In addition, T-cell activation generally requires binding of this same pMHC to a CD4 or CD8 coreceptor. Here, we report the structure of a complete TCR-pMHC-CD4 ternary complex involving a human autoimmune TCR, a myelin-derived self-peptide bound to HLA-DR4, and CD4. The complex resembles a pointed arch in which TCR and CD4 are each tilted ~65° relative to the T-cell membrane. By precluding direct contacts between TCR and CD4, the structure explainsmore » how TCR and CD4 on the T cell can simultaneously, yet independently, engage the same pMHC on the APC. The structure, in conjunction with previous mutagenesis data, places TCR-associated CD3εγ and CD3εδ subunits, which transmit activation signals to the T cell, inside the TCR-pMHC-CD4 arch, facing CD4. By establishing anchor points for TCR and CD4 on the T-cell membrane, the complex provides a basis for understanding how the CD4 coreceptor focuses TCR on MHC to guide TCR docking on pMHC during thymic T-cell selection.« less

Downregulation of cathepsin G reduces the activation of CD4+ T cells in murine autoimmune diabetes.

PubMed

Zou, Fang; Lai, Xiaoyang; Li, Jing; Lei, Shuihong; Hu, Lei

2017-01-01

Type 1 diabetes mellitus (T1DM) is an autoimmune disease due to progressive injury of islet cells mediated by T lymphocytes (T cells). Our previous studies have shown that only cathepsin G (CatG), not other proteases, is involved in the antigen presentation of proinsulin, and if the presentation is inhibited, the activation of CD4+ T cells induced by proinsulin is alleviated in T1DM patients, and CatG-specific inhibitor reduces the activation of CD4+ cells induced by proinsulin in T1DM patients. Therefore, we hypothesize that CatG may play an important role in the activation of CD4+ T cells in T1DM. To this end, mouse studies were conducted to demonstrate that CatG impacts the activation of CD4+ T cells in non-obese diabetic (NOD) mice. CatG gene expression and the activation of CD4+ T cells were examined in NOD mice. The effect of CatG inhibitor was investigated in NOD mice on the activation of CD4+ T cells, islet β cell function, islet inflammation and β-cell apoptosis. Furthermore, NOD mice were injected with CatG siRNA in early stage to observe the effect of CatG knockdown on the activation status of CD4+ T cells and the progression of diabetes. During the pathogenesis of diabetes, the expression level of CatG in NOD mice gradually increased and the CD4+ T cells were gradually activated, resulting in more TH1 cells and less TH2 and Treg cells. Treatment with CatG-specific inhibitor reduced the blood glucose level, improved the function of islet β cells and reduced the activation of CD4+ T cells. Early application of CatG siRNA improved the function of islet β cells, reduced islet inflammation and β cell apoptosis, and lowered the activation level of CD4+ T cells, thus slowing down the progression of diabetes.

Downregulation of cathepsin G reduces the activation of CD4+ T cells in murine autoimmune diabetes

PubMed Central

Zou, Fang; Lai, Xiaoyang; Li, Jing; Lei, Shuihong; Hu, Lei

2017-01-01

Type 1 diabetes mellitus (T1DM) is an autoimmune disease due to progressive injury of islet cells mediated by T lymphocytes (T cells). Our previous studies have shown that only cathepsin G (CatG), not other proteases, is involved in the antigen presentation of proinsulin, and if the presentation is inhibited, the activation of CD4+ T cells induced by proinsulin is alleviated in T1DM patients, and CatG-specific inhibitor reduces the activation of CD4+ cells induced by proinsulin in T1DM patients. Therefore, we hypothesize that CatG may play an important role in the activation of CD4+ T cells in T1DM. To this end, mouse studies were conducted to demonstrate that CatG impacts the activation of CD4+ T cells in non-obese diabetic (NOD) mice. CatG gene expression and the activation of CD4+ T cells were examined in NOD mice. The effect of CatG inhibitor was investigated in NOD mice on the activation of CD4+ T cells, islet β cell function, islet inflammation and β-cell apoptosis. Furthermore, NOD mice were injected with CatG siRNA in early stage to observe the effect of CatG knockdown on the activation status of CD4+ T cells and the progression of diabetes. During the pathogenesis of diabetes, the expression level of CatG in NOD mice gradually increased and the CD4+ T cells were gradually activated, resulting in more TH1 cells and less TH2 and Treg cells. Treatment with CatG-specific inhibitor reduced the blood glucose level, improved the function of islet β cells and reduced the activation of CD4+ T cells. Early application of CatG siRNA improved the function of islet β cells, reduced islet inflammation and β cell apoptosis, and lowered the activation level of CD4+ T cells, thus slowing down the progression of diabetes. PMID:29218110

Human umbilical cord mesenchymal stem cells increase interleukin-9 production of CD4+ T cells

PubMed Central

Yang, Zhou Xin; Chi, Ying; Ji, Yue Ru; Wang, You Wei; Zhang, Jing; Luo, Wei Feng; Li, Li Na; Hu, Cai Dong; Zhuo, Guang Sheng; Wang, Li Fang; Han, Zhi-Bo; Han, Zhong Chao

2017-01-01

Mesenchymal stem cells (MSC) are able to differentiate into cells of multiple lineage, and additionally act to modulate the immune response. Interleukin (IL)-9 is primarily produced by cluster of differentiation (CD)4+ T cells to regulate the immune response. The present study aimed to investigate the effect of human umbilical cord derived-MSC (UC-MSC) on IL-9 production of human CD4+ T cells. It was demonstrated that the addition of UC-MSC to the culture of CD4+ T cells significantly enhanced IL-9 production by CD4+ T cells. Transwell experiments suggested that UC-MSC promotion of IL-9 production by CD4+ T cells was dependent on cell-cell contact. Upregulated expression of CD106 was observed in UC-MSC co-cultured with CD4+ T cells, and the addition of a blocking antibody of CD106 significantly impaired the ability of UC-MSC to promote IL-9 production by CD4+ T cells. Therefore, the results of the present study demonstrated that UC-MSC promoted the generation of IL-9 producing cells, which may be mediated, in part by CD106. The findings may act to expand understanding and knowledge of the immune modulatory role of UC-MSC. PMID:29042945

Effect of human bone marrow mesenchymal stromal cells on cytokine production by peripheral blood naive, memory, and effector T cells.

PubMed

Laranjeira, Paula; Pedrosa, Monia; Pedreiro, Susana; Gomes, Joana; Martinho, Antonio; Antunes, Brigida; Ribeiro, Tania; Santos, Francisco; Trindade, Helder; Paiva, Artur

2015-01-05

The different distribution of T cells among activation/differentiation stages in immune disorders may condition the outcome of mesenchymal stromal cell (MSC)-based therapies. Indeed, the effect of MSCs in the different functional compartments of T cells is not completely elucidated. We investigated the effect of human bone marrow MSCs on naturally occurring peripheral blood functional compartments of CD4(+) and CD8(+) T cells: naive, central memory, effector memory, and effector compartments. For that, mononuclear cells (MNCs) stimulated with phorbol myristate acetate (PMA) plus ionomycin were cultured in the absence/presence of MSCs. The percentage of cells expressing tumor necrosis factor-alpha (TNF-α), interferon gamma (IFNγ), and interleukin-2 (IL-2), IL-17, IL-9, and IL-6 and the amount of cytokine produced were assessed by flow cytometry. mRNA levels of IL-4, IL-10, transforming growth factor-beta (TGF-β), and cytotoxic T-lymphocyte-associated protein 4 (CTLA4) in purified CD4(+) and CD8(+) T cells, and phenotypic and mRNA expression changes induced by PMA + ionomycin stimulation in MSCs, were also evaluated. MSCs induced the reduction of the percentage of CD4(+) and CD8(+) T cells producing TNF-α, IFNγ, and IL-2 in all functional compartments, except for naive IFNγ(+)CD4(+) T cells. This inhibitory effect differentially affected CD4(+) and CD8(+) T cells as well as the T-cell functional compartments; remarkably, different cytokines showed distinct patterns of inhibition regarding both the percentage of producing cells and the amount of cytokine produced. Likewise, the percentages of IL-17(+), IL-17(+)TNF-α(+), and IL-9(+) within CD4(+) and CD8(+) T cells and of IL-6(+)CD4(+) T cells were decreased in MNC-MSC co-cultures. MSCs decreased IL-10 and increased IL-4 mRNA expression in stimulated CD4(+) and CD8(+) T cells, whereas TGF-β was reduced in CD8(+) and augmented in CD4(+) T cells, with no changes for CTLA4. Finally, PMA + ionomycin stimulation did not induce significant alterations on MSCs phenotype but did increase indoleamine-2,3-dioxygenase (IDO), inducible costimulatory ligand (ICOSL), IL-1β, IL-8, and TNF-α mRNA expression. Overall, our study showed that MSCs differentially regulate the functional compartments of CD4(+) and CD8(+) T cells, which may differentially impact their therapeutic effect in immune disorders. Furthermore, the influence of MSCs on IL-9 expression can open new possibilities for MSC-based therapy in allergic diseases.

PD-1(HIGH) Follicular CD4 T Helper Cell Subsets Residing in Lymph Node Germinal Centers Correlate with B Cell Maturation and IgG Production in Rhesus Macaques.

PubMed

Xu, Huanbin; Wang, Xiaolei; Lackner, Andrew A; Veazey, Ronald S

2014-01-01

CD4+ T follicular helper (TFH) cells guide development and maturation of B cells and are crucial for effective antibody responses. Here we found rhesus macaque TFH cells, defined as CXCR5+CD4 T cells, contain two major populations: PD-1(INT) and PD-1(HIGH) cells. Of these, PD-1(HIGH)CD4+ T cells highly co-express ICOS but little CCR7, and reside in lymph node germinal centers (GCs), but not in blood. These cells secrete IL-21 and express transcriptional factor Bcl-6 at higher levels than CXCR5+PD-1(INT)CD4+ T cells. In addition, the frequency of PD-1(HIGH)CD4+ T cells is low in lymph nodes of newborns, but increases with age. Levels of PD-1(HIGH)CD4+ T cells correlate with mature B cells in lymph nodes, and PD-1 blockade in PD-1(HIGH)CD4+ T and B cell co-cultures significantly inhibits IgG production. In summary, PD-1(HIGH)CD4+ T cells residing in GC represent a specific TFH subset that contributes to maturation of B cells and IgG production.

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

PubMed

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

2012-04-01

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

Dynamics of CCR5 Expression by CD4+ T Cells in Lymphoid Tissues during Simian Immunodeficiency Virus Infection

PubMed Central

Veazey, Ronald S.; Mansfield, Keith G.; Tham, Irene C.; Carville, Angela C.; Shvetz, Daniel E.; Forand, Amy E.; Lackner, Andrew A.

2000-01-01

Early viral replication and profound CD4+ T-cell depletion occur preferentially in intestinal tissues of macaques infected with simian immunodeficiency virus (SIV). Here we show that a much higher percentage of CD4+ T cells in the intestine express CCR5 compared with those found in the peripheral blood, spleen, or lymph nodes. In addition, the selectivity and extent of the CD4+ T-cell loss in SIV infection may depend upon these cells coexpressing CCR5 and having a “memory” phenotype (CD45RA−). Following intravenous infection with SIVmac251, memory CD4+ CCR5+ T cells were selectively eliminated within 14 days in all major lymphoid tissues (intestine, spleen, and lymph nodes). However, the effect on CD4+ T-cell numbers was most profound in the intestine, where cells of this phenotype predominate. The CD4+ T cells that remain after 14 days of infection lacked CCR5 and/or were naive (CD45RA+). Furthermore, when animals in the terminal stages of SIV infection (with AIDS) were examined, virtually no CCR5-expressing CD4+ T cells were found in lymphoid tissues, and all of the remaining CD4+ T cells were naive and coexpressed CXCR4. These findings suggest that chemokine receptor usage determines which cells are targeted for SIV infection and elimination in vivo. PMID:11069995

CD4+ Foxp3+ T cells promote aberrant immunoglobulin G production and maintain CD8+ T-cell suppression during chronic liver disease.

PubMed

Tedesco, Dana; Thapa, Manoj; Gumber, Sanjeev; Elrod, Elizabeth J; Rahman, Khalidur; Ibegbu, Chris C; Magliocca, Joseph F; Adams, Andrew B; Anania, Frank; Grakoui, Arash

2017-02-01

Persistent hepatotropic viral infections are a common etiologic agent of chronic liver disease. Unresolved infection can be attributed to nonfunctional intrahepatic CD8+ T-cell responses. In light of dampened CD8 + T-cell responses, liver disease often manifests systemically as immunoglobulin (Ig)-related syndromes due to aberrant B-cell functions. These two opposing yet coexisting phenomena implicate the potential of altered CD4 + T-cell help. Elevated CD4 + forkhead box P3-positive (Foxp3+) T cells were evident in both human liver disease and a mouse model of chemically induced liver injury despite marked activation and spontaneous IgG production by intrahepatic B cells. While this population suppressed CD8 + T-cell responses, aberrant B-cell activities were maintained due to expression of CD40 ligand on a subset of CD4 + Foxp3+ T cells. In vivo blockade of CD40 ligand attenuated B-cell abnormalities in a mouse model of liver injury. A phenotypically similar population of CD4 + Foxp3+, CD40 ligand-positive T cells was found in diseased livers explanted from patients with chronic hepatitis C infection. This population was absent in nondiseased liver tissues and peripheral blood. Liver disease elicits alterations in the intrahepatic CD4 + T-cell compartment that suppress T-cell immunity while concomitantly promoting aberrant IgG mediated manifestations. (Hepatology 2017;65:661-677). © 2016 by the American Association for the Study of Liver Diseases.

The exhausted CD4+CXCR5+ T cells involve the pathogenesis of human tuberculosis disease.

PubMed

Bosco, Munyemana Jean; Wei, Ming; Hou, Hongyan; Yu, Jing; Lin, Qun; Luo, Ying; Sun, Ziyong; Wang, Feng

2018-06-21

The CD4 + CXCR5 + T cells have been previously established. However, their decreased frequency during tuberculosis (TB) disease is partially understood. The aim of this study was to explore the depletion of CD4 + CXCR5 + T cells in human TB. The frequency and function of CD4 + CXCR5 + T cells were evaluated in active TB (ATB) patients and healthy control (HC) individuals. The function of CD4 + CXCR5 + T cells was determined after blockade of inhibitory receptors. The frequency of CD4 + CXCR5 + T cells was decreased in ATB patients. The expression of activation markers (HLA-DR and ICOS) and inhibitory receptors (Tim-3 and PD-1) on CD4 + CXCR5 + T cells was increased in ATB group. TB-specific antigen stimulation induced higher expression of inhibitory receptors than phytohemagglutinin stimulation in ATB group. In contrast, TB antigen stimulation did not induce a significantly increased expression of IL-21 and Ki-67 on CD4 + CXCR5 + T cells. However, blockade of inhibitory receptors Tim-3 and PD-1 not only increased the frequency of CD4 + CXCR5 + T cells, but also restored their proliferation and cytokine secretion potential. An increased expression of inhibitory receptors involves the depletion of CD4 + CXCR5 + T cells, and blockade of inhibitory receptors can restore the function of CD4 + CXCR5 + T cells in ATB patients. Copyright © 2018. Published by Elsevier Ltd.

Upregulation of GRAIL is associated with impaired CD4 T cell proliferation in sepsis.

PubMed

Aziz, Monowar; Yang, Weng-Lang; Matsuo, Shingo; Sharma, Archna; Zhou, Mian; Wang, Ping

2014-03-01

The loss of numbers and functionality of CD4 T cells is observed in sepsis; however, the mechanism remains elusive. Gene related to anergy in lymphocytes (GRAIL) is critical for the impairment of CD4 T cell proliferation. We therefore sought to examine the role of GRAIL in CD4 T cell proliferation during sepsis. Sepsis was induced in 10-wk-old male C57BL/6 mice by cecal ligation and puncture. Splenocytes were isolated and subjected to flow cytometry to determine CD4 T cell contents. CD4 T cell proliferation was assessed by CFSE staining, and the expression of GRAIL in splenocytes was measured by immunohistochemistry, real-time PCR, and flow cytometry. The expressions of IL-2 and early growth response-2 were determined by real-time PCR. As compared with shams, the numbers of CD4 T cells were significantly reduced in spleens. Septic CD4 T cells were less efficient in proliferation than shams. The IL-2 expression was significantly reduced, whereas the GRAIL expression was significantly increased in septic mice splenocytes as compared with shams. The small interfering RNA-mediated knockdown of GRAIL expression re-established the CD4 T cell proliferation ability ex vivo. Similarly, the treatment with recombinant murine IL-2 to the septic CD4 T cells restored their proliferation ability by downregulating GRAIL expression. Our findings reveal a novel association of the increased GRAIL expression with impaired CD4 T cell proliferation, implicating an emerging therapeutic tool in sepsis.

Differential usage of T-cell receptor V beta gene families by CD4+ and CD8+ T cells in patients with CD8hi common variable immunodeficiency: evidence of a post-thymic effect.

PubMed Central

Duchmann, R; Jaffe, J; Ehrhardt, R; Alling, D W; Strober, W

1996-01-01

In this study, we report that differences between T-cell receptor (TCR) V beta gene family usage in CD4+ and CD8+ T cells are significantly greater in a subgroup of patients with common variable immunodeficiency (CVI) and high levels of activated CD8+ T cells (CD8hi CVI) than in controls (P < 0.001). In CD8hi CVI patients, such differences were also significantly greater for V beta 12 than for other V beta families. As the causes of the differential usage of V beta gene families by CD4+ and CD8+ T cells are under investigation, it was interesting that the combined differences between V beta gene family usage in the CD4+ and CD8+ T-cell subpopulations as a whole were significantly lower than the combined differences between individual V beta gene family usage in either CD4+ or CD8+ T-cell subpopulations (P < 0.001 in both control and CD8hi CVI patients). Further, the pattern of V beta gene family usage in CD4+ T cells was remarkably similar to that in CD8+ T cells in both groups. These data strongly suggest that differences in V beta gene family usage arising from coselection by major histocompatibility complex (MHC) class I versus MHC class II restriction elements do not fundamentally distort 'basic' V beta gene family usage patterns. They also support the concept that differences in CD4+ and CD8+ T-cell V beta gene family usage, which were increased in CD8hi CVI, can arise from high-affinity interactions between disease-associated antigens or superantigens and T cells in the post-thymic T-cell compartment. Images Figure 6 PMID:8666443

Human mesenchymal stromal cells enhance the immunomodulatory function of CD8+CD28− regulatory T cells

PubMed Central

Liu, Qiuli; Zheng, Haiqing; Chen, Xiaoyong; Peng, Yanwen; Huang, Weijun; Li, Xiaobo; Li, Gang; Xia, Wenjie; Sun, Qiquan; Xiang, Andy Peng

2015-01-01

One important aspect of mesenchymal stromal cells (MSCs)-mediated immunomodulation is the recruitment and induction of regulatory T (Treg) cells. However, we do not yet know whether MSCs have similar effects on the other subsets of Treg cells. Herein, we studied the effects of MSCs on CD8+CD28− Treg cells and found that the MSCs could not only increase the proportion of CD8+CD28− T cells, but also enhance CD8+CD28−T cells' ability of hampering naive CD4+ T-cell proliferation and activation, decreasing the production of IFN-γ by activated CD4+ T cells and inducing the apoptosis of activated CD4+ T cells. Mechanistically, the MSCs affected the functions of the CD8+CD28− T cells partially through moderate upregulating the expression of IL-10 and FasL. The MSCs had no distinct effect on the shift from CD8+CD28+ T cells to CD8+CD28− T cells, but did increase the proportion of CD8+CD28− T cells by reducing their rate of apoptosis. In summary, this study shows that MSCs can enhance the regulatory function of CD8+CD28− Treg cells, shedding new light on MSCs-mediated immune regulation. PMID:25482073

Development of a Novel CD4+ TCR Transgenic Line That Reveals a Dominant Role for CD8+ Dendritic Cells and CD40 Signaling in the Generation of Helper and CTL Responses to Blood-Stage Malaria.

PubMed

Fernandez-Ruiz, Daniel; Lau, Lei Shong; Ghazanfari, Nazanin; Jones, Claerwen M; Ng, Wei Yi; Davey, Gayle M; Berthold, Dorothee; Holz, Lauren; Kato, Yu; Enders, Matthias H; Bayarsaikhan, Ganchimeg; Hendriks, Sanne H; Lansink, Lianne I M; Engel, Jessica A; Soon, Megan S F; James, Kylie R; Cozijnsen, Anton; Mollard, Vanessa; Uboldi, Alessandro D; Tonkin, Christopher J; de Koning-Ward, Tania F; Gilson, Paul R; Kaisho, Tsuneyasu; Haque, Ashraful; Crabb, Brendan S; Carbone, Francis R; McFadden, Geoffrey I; Heath, William R

2017-12-15

We describe an MHC class II (I-A b )-restricted TCR transgenic mouse line that produces CD4 + T cells specific for Plasmodium species. This line, termed PbT-II, was derived from a CD4 + T cell hybridoma generated to blood-stage Plasmodium berghei ANKA (PbA). PbT-II cells responded to all Plasmodium species and stages tested so far, including rodent (PbA, P. berghei NK65, Plasmodium chabaudi AS, and Plasmodium yoelii 17XNL) and human ( Plasmodium falciparum ) blood-stage parasites as well as irradiated PbA sporozoites. PbT-II cells can provide help for generation of Ab to P. chabaudi infection and can control this otherwise lethal infection in CD40L-deficient mice. PbT-II cells can also provide help for development of CD8 + T cell-mediated experimental cerebral malaria (ECM) during PbA infection. Using PbT-II CD4 + T cells and the previously described PbT-I CD8 + T cells, we determined the dendritic cell (DC) subsets responsible for immunity to PbA blood-stage infection. CD8 + DC (a subset of XCR1 + DC) were the major APC responsible for activation of both T cell subsets, although other DC also contributed to CD4 + T cell responses. Depletion of CD8 + DC at the beginning of infection prevented ECM development and impaired both Th1 and follicular Th cell responses; in contrast, late depletion did not affect ECM. This study describes a novel and versatile tool for examining CD4 + T cell immunity during malaria and provides evidence that CD4 + T cell help, acting via CD40L signaling, can promote immunity or pathology to blood-stage malaria largely through Ag presentation by CD8 + DC. Copyright © 2017 by The American Association of Immunologists, Inc.

CD4+ memory T cells retain surface expression of CD31 independently of thymic function in patients with lymphoproliferative disorders following autologous hematopoietic stem-cell transplantation.

PubMed

Batorov, Egor V; Tikhonova, Marina A; Kryuchkova, Irina V; Sergeevicheva, Vera V; Sizikova, Svetlana A; Ushakova, Galina Y; Batorova, Dariya S; Gilevich, Andrey V; Ostanin, Alexander A; Shevela, Ekaterina Y; Chernykh, Elena R

2017-07-01

High-dose chemotherapy with autologous hematopoietic stem-cell transplantation (AHSCT) causes severe and long-lasting immunodeficiency in patients with lymphoproliferative disorders. The thymus begins to restore the T-cell repertoire approximately from the sixth month post-transplant. We assessed the dynamics of post-transplant recovery of CD4 + CD45RA + CD31 + T cells, "recent thymic emigrants" (RTEs), and a poorly described subtype of CD4 + CD45RA - CD31 + T cells in 90 patients with lymphoproliferative disorders following high-dose chemotherapy with AHSCT. Relative and absolute counts of CD4 + CD31 + naïve and memory T cells were evaluated before AHSCT, at the day of engraftment, and 6- and 12-month post-transplant. The pre-transplant count of CD4 + CD45RA + CD31 + T cells was lower than in healthy controls, and did not reach donors' values during the 12-month period. The pre-transplant number of CD4 + CD45RA - CD31 + T cells was higher than in healthy controls and was restored rapidly following AHSCT. Post-transplant mediastinal radiotherapy reduced counts of RTEs and elongated recovery period. Non-thymic tissue irradiation did not reduce this subset. The obtained data indicate that homeostatic proliferation may decrease the significance of CD31 expression on CD4 + CD45RA + T cells as a marker of RTEs, and suggest that evaluation of RTEs recovery by flow cytometry requires an accurate gating strategy to exclude CD31 + memory T cells.

Assessment of metabolic and mitochondrial dynamics in CD4+ and CD8+ T cells in virologically suppressed HIV-positive individuals on combination antiretroviral therapy.

PubMed

Masson, Jesse J R; Murphy, Andrew J; Lee, Man K S; Ostrowski, Matias; Crowe, Suzanne M; Palmer, Clovis S

2017-01-01

Metabolism plays a fundamental role in supporting the growth, proliferation and effector functions of T cells. We investigated the impact of HIV infection on key processes that regulate glucose uptake and mitochondrial biogenesis in subpopulations of CD4+ and CD8+ T cells from 18 virologically-suppressed HIV-positive individuals on combination antiretroviral therapy (cART; median CD4+ cell count: 728 cells/μl) and 13 HIV seronegative controls. Mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) production were also analysed in total CD4+ and CD8+ T cells. Among HIV+/cART individuals, expression of glucose transporter (Glut1) and mitochondrial density were highest within central memory and naïve CD4+ T cells, and lowest among effector memory and transitional memory T cells, with similar trends in HIV-negative controls. Compared to HIV-negative controls, there was a trend towards higher percentage of circulating CD4+Glut1+ T cells in HIV+/cART participants. There were no significant differences in mitochondrial dynamics between subject groups. Glut1 expression was positively correlated with mitochondrial density and MMP in total CD4+ T cells, while MMP was also positively correlated with ROS production in both CD4+ and CD8+ T cells. Our study characterizes specific metabolic features of CD4+ and CD8+ T cells in HIV-negative and HIV+/cART individuals and will invite future studies to explore the immunometabolic consequences of HIV infection.

CD4 cells can be more efficient at tumor rejection than CD8 cells.

PubMed

Perez-Diez, Ainhoa; Joncker, Nathalie T; Choi, Kyungho; Chan, William F N; Anderson, Colin C; Lantz, Olivier; Matzinger, Polly

2007-06-15

Researchers designing antitumor treatments have long focused on eliciting tumor-specific CD8 cytotoxic T lymphocytes (CTL) because of their potent killing activity and their ability to reject transplanted organs. The resulting treatments, however, have generally been surprisingly poor at inducing complete tumor rejection, both in experimental models and in the clinic. Although a few scattered studies suggested that CD4 T "helper" cells might also serve as antitumor effectors, they have generally been studied mostly for their ability to enhance the activity of CTL. In this mouse study, we compared monoclonal populations of tumor-specific CD4 and CD8 T cells as effectors against several different tumors, and found that CD4 T cells eliminated tumors that were resistant to CD8-mediated rejection, even in cases where the tumors expressed major histocompatibility complex (MHC) class I molecules but not MHC class II. MHC class II expression on host tissues was critical, suggesting that the CD4 T cells act indirectly. Indeed, the CD4 T cells partnered with NK cells to obtain the maximal antitumor effect. These findings suggest that CD4 T cells can be powerful antitumor effector cells that can, in some cases, outperform CD8 T cells, which are the current "gold standard" effector cell in tumor immunotherapy.

Reduced Plasmodium Parasite Burden Associates with CD38+ CD4+ T Cells Displaying Cytolytic Potential and Impaired IFN-γ Production

PubMed Central

Burel, Julie G.; Apte, Simon H.; Groves, Penny L.; Klein, Kerenaftali; McCarthy, James S.; Doolan, Denise L.

2016-01-01

Using a unique resource of samples from a controlled human malaria infection (CHMI) study, we identified a novel population of CD4+ T cells whose frequency in the peripheral blood was inversely correlated with parasite burden following P. falciparum infection. These CD4+ T cells expressed the multifunctional ectoenzyme CD38 and had unique features that distinguished them from other CD4+ T cells. Specifically, their phenotype was associated with proliferation, activation and cytotoxic potential as well as significantly impaired production of IFN-γ and other cytokines and reduced basal levels of activated STAT1. A CD38+ CD4+ T cell population with similar features was identified in healthy uninfected individuals, at lower frequency. CD38+ CD4+ T cells could be generated in vitro from CD38- CD4+ T cells after antigenic or mitogenic stimulation. This is the first report of a population of CD38+ CD4+ T cells with a cytotoxic phenotype and markedly impaired IFN-γ capacity in humans. The expansion of this CD38+ CD4+ T population following infection and its significant association with reduced blood-stage parasite burden is consistent with an important functional role for these cells in protective immunity to malaria in humans. Their ubiquitous presence in humans suggests that they may have a broad role in host-pathogen defense. Trial Registration ClinicalTrials.gov clinical trial numbers ACTRN12612000814875, ACTRN12613000565741 and ACTRN12613001040752 PMID:27662621

Distinct Roles for CXCR6(+) and CXCR6(-) CD4(+) T Cells in the Pathogenesis of Chronic Colitis.

PubMed

Mandai, Yasushi; Takahashi, Daisuke; Hase, Koji; Obata, Yuuki; Furusawa, Yukihiro; Ebisawa, Masashi; Nakagawa, Tomoo; Sato, Toru; Katsuno, Tatsuro; Saito, Yasushi; Shimaoka, Takeshi; Yokosuka, Osamu; Yokote, Kotaro; Ohno, Hiroshi

2013-01-01

CD4(+) T cells play a central role in the development of inflammatory bowel disease (IBD) via high-level production of effector cytokines such as IFN-γ and TNF-α. To better characterize the colitogenic CD4(+) T cells, we examined their expression of CXCR6, a chemokine receptor that is expressed by T cells upon activation and is upregulated in several inflammatory diseases. We found that 80% of colonic lamina propria CD4(+) T cells expressed CXCR6 in the CD45RB(high) T cell-transferred colitis model. CXCR6 expression was similarly upregulated in inflamed mucosa of patients with Crohn's disease. Although surface marker analysis demonstrated that both CXCR6(+) and CXCR6(-) CD4(+) T-cell subsets consist of the cells with effector and effector-memory cells, the more cells in the CXCR6(+) subset produced IFN-γ and TNF-α compared to CXCR6(-) subset, and only the CXCR6(+) subset produced IL-17A. Nevertheless, adoptive retransfer of lamina propria CXCR6(+) T cells into Rag1 (-/-) recipients failed to induce the disease due to limited expansion of the transferred cells. By contrast, retransfer of CXCR6(-) cells evoked colitis similar to that observed in CD4(+)CD45RB(high) T cell-transferred mice, and resulted in their conversion into CXCR6(+) cells. Collectively, these observations suggest that the CXCR6(+)CD4(+) T-cell subset consists of terminally differentiated effector cells that serve as the major source of effector cytokines in the inflamed tissue, whereas CXCR6(-)CD4(+) T-cell subset serves as a colitogenic memory compartment that retains the ability to proliferate and differentiate into CXCR6(+)CD4(+) T cells.

Distinct Roles for CXCR6+ and CXCR6− CD4+ T Cells in the Pathogenesis of Chronic Colitis

PubMed Central

Hase, Koji; Obata, Yuuki; Furusawa, Yukihiro; Ebisawa, Masashi; Nakagawa, Tomoo; Sato, Toru; Katsuno, Tatsuro; Saito, Yasushi; Shimaoka, Takeshi; Yokosuka, Osamu; Yokote, Kotaro; Ohno, Hiroshi

2013-01-01

CD4+ T cells play a central role in the development of inflammatory bowel disease (IBD) via high-level production of effector cytokines such as IFN-γ and TNF-α. To better characterize the colitogenic CD4+ T cells, we examined their expression of CXCR6, a chemokine receptor that is expressed by T cells upon activation and is upregulated in several inflammatory diseases. We found that 80% of colonic lamina propria CD4+ T cells expressed CXCR6 in the CD45RBhigh T cell-transferred colitis model. CXCR6 expression was similarly upregulated in inflamed mucosa of patients with Crohn’s disease. Although surface marker analysis demonstrated that both CXCR6+ and CXCR6− CD4+ T-cell subsets consist of the cells with effector and effector-memory cells, the more cells in the CXCR6+ subset produced IFN-γ and TNF-α compared to CXCR6− subset, and only the CXCR6+ subset produced IL-17A. Nevertheless, adoptive retransfer of lamina propria CXCR6+ T cells into Rag1 −/− recipients failed to induce the disease due to limited expansion of the transferred cells. By contrast, retransfer of CXCR6− cells evoked colitis similar to that observed in CD4+CD45RBhigh T cell-transferred mice, and resulted in their conversion into CXCR6+ cells. Collectively, these observations suggest that the CXCR6+CD4+ T-cell subset consists of terminally differentiated effector cells that serve as the major source of effector cytokines in the inflamed tissue, whereas CXCR6−CD4+ T-cell subset serves as a colitogenic memory compartment that retains the ability to proliferate and differentiate into CXCR6+CD4+ T cells. PMID:23840334

The composition of T cell subtypes in duodenal biopsies are altered in coeliac disease patients

PubMed Central

Steenholt, Janni V.; Nielsen, Christian; Baudewijn, Leen; Staal, Anne; Rasmussen, Karina S.; Sabir, Hardee J.; Barington, Torben; Husby, Steffen; Toft-Hansen, Henrik

2017-01-01

One of the hallmarks of Celiac disease (CD) is intraepithelial lymphocytosis in the small intestine. Until now, investigations to characterize the T cell subpopulations within the epithelial layer have not discriminated between the heterodimeric co-receptor molecule, CD8αβ, and the possibly immunoregulatory CD8αα homodimer molecule. Besides TCRαβ+ CD4+ cells, no other phenotypes have been shown to be gluten-reactive. Using flow cytometry on lymphocytes from duodenal biopsies, we determined that the number of B cells (CD3- CD19+) and the number of CD3+ CD4- CD8- double-negative (DN) T cells were elevated 6–7 fold in children with CD. We next isolated and quantified intraepithelial lymphocytes (IELs) from biopsies obtained from patients (both children and adults) with CD, potential CD and non-CD controls. Flow cytometric analysis of the duodenal T cell subpopulations was performed including the markers TCRαβ, TCRγδ, CD4, CD8α and CD8β. Proportions of γδ T cells and CD8αβ+ cells among IELs were increased in CD patients, whereas proportions of CD4+ CD8αα+ and CD4+ single-positive T cells were decreased. Additionally, two gluten-reactive T cell lines (TCLs) derived from CD biopsies were analyzed for changes in proportions of T cell subsets before and after gluten stimulation. In a proliferation assay, dividing cells were tracked with carboxyfluorescein succinimidyl ester (CFSE), and both αβ and γδ T cells proliferated in response to gluten. Changes in duodenal T cell subpopulations in potential CD patients followed the same pattern as for CD patients, but with less pronounced effect. PMID:28166225

Expansion in CD39+ CD4+ Immunoregulatory T Cells and Rarity of Th17 Cells in HTLV-1 Infected Patients Is Associated with Neurological Complications

PubMed Central

Hasenkrug, Aaron M.; Bruno, Fernanda R.; Carvalho, Karina I.; Wynn-Williams, Harry; Neto, Walter K.; Sanabani, Sabri S.; Segurado, Aluisio C.; Nixon, Douglas F.; Kallas, Esper G.

2013-01-01

HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is unclear why a minority of infected subjects develops HAM/TSP. CD4+ T cells are the main target of infection and play a pivotal role in regulating immunity to HTLV and are hypothesized to participate in the pathogenesis of HAM/TSP. The CD39 ectonucleotidase receptor is expressed on CD4+ T cells and based on co-expression with CD25, marks T cells with distinct regulatory (CD39+CD25+) and effector (CD39+CD25−) function. Here, we investigated the expression of CD39 on CD4+ T cells from a cohort of HAM/TSP patients, HTLV-1 asymptomatic carriers (AC), and matched uninfected controls. The frequency of CD39+ CD4+ T cells was increased in HTLV-1 infected patients, regardless of clinical status. More importantly, the proportion of the immunostimulatory CD39+CD25− CD4+ T-cell subset was significantly elevated in HAM/TSP patients as compared to AC and phenotypically had lower levels of the immunoinhibitory receptor, PD-1. We saw no difference in the frequency of CD39+CD25+ regulatory (Treg) cells between AC and HAM/TSP patients. However, these cells transition from being anergic to displaying a polyfunctional cytokine response following HTLV-1 infection. CD39−CD25+ T cell subsets predominantly secreted the inflammatory cytokine IL-17. We found that HAM/TSP patients had significantly fewer numbers of IL-17 secreting CD4+ T cells compared to uninfected controls. Taken together, we show that the expression of CD39 is upregulated on CD4+ T cells HAM/TSP patients. This upregulation may play a role in the development of the proinflammatory milieu through pathways both distinct and separate among the different CD39 T cell subsets. CD39 upregulation may therefore serve as a surrogate diagnostic marker of progression and could potentially be a target for interventions to reduce the development of HAM/TSP. PMID:23409198

Potential contribution of a novel Tax epitope-specific CD4+ T cells to graft-versus-Tax effect in adult T cell leukemia patients after allogeneic hematopoietic stem cell transplantation.

PubMed

Tamai, Yotaro; Hasegawa, Atsuhiko; Takamori, Ayako; Sasada, Amane; Tanosaki, Ryuji; Choi, Ilseung; Utsunomiya, Atae; Maeda, Yasuhiro; Yamano, Yoshihisa; Eto, Tetsuya; Koh, Ki-Ryang; Nakamae, Hirohisa; Suehiro, Youko; Kato, Koji; Takemoto, Shigeki; Okamura, Jun; Uike, Naokuni; Kannagi, Mari

2013-04-15

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an effective treatment for adult T cell leukemia/lymphoma (ATL) caused by human T cell leukemia virus type 1 (HTLV-1). We previously reported that Tax-specific CD8(+) cytotoxic T lymphocyte (CTL) contributed to graft-versus-ATL effects in ATL patients after allo-HSCT. However, the role of HTLV-1-specific CD4(+) T cells in the effects remains unclear. In this study, we showed that Tax-specific CD4(+) as well as CD8(+) T cell responses were induced in some ATL patients following allo-HSCT. To further analyze HTLV-1-specific CD4(+) T cell responses, we identified a novel HLA-DRB1*0101-restricted epitope, Tax155-167, recognized by HTLV-1-specific CD4(+) Th1-like cells, a major population of HTLV-1-specific CD4(+) T cell line, which was established from an ATL patient at 180 d after allo-HSCT from an unrelated seronegative donor by in vitro stimulation with HTLV-1-infected cells from the same patient. Costimulation of PBMCs with both the identified epitope (Tax155-167) and known CTL epitope peptides markedly enhanced the expansion of Tax-specific CD8(+) T cells in PBMCs compared with stimulation with CTL epitope peptide alone in all three HLA-DRB1*0101(+) patients post-allo-HSCT tested. In addition, direct detection using newly generated HLA-DRB1*0101/Tax155-167 tetramers revealed that Tax155-167-specific CD4(+) T cells were present in all HTLV-1-infected individuals tested, regardless of HSCT. These results suggest that Tax155-167 may be the dominant epitope recognized by HTLV-1-specific CD4(+) T cells in HLA-DRB1*0101(+)-infected individuals and that Tax-specific CD4(+) T cells may augment the graft-versus-Tax effects via efficient induction of Tax-specific CD8(+) T cell responses.

Loss of T cell precursors after spaceflight and exposure to vector-averaged gravity

NASA Technical Reports Server (NTRS)

Woods, Chris C.; Banks, Krista E.; Gruener, Raphael; DeLuca, Dominick

2003-01-01

Using fetal thymus organ culture (FTOC), we examined the effects of spaceflight and vector-averaged gravity on T cell development. Under both conditions, the development of T cells was significantly attenuated. Exposure to spaceflight for 16 days resulted in a loss of precursors for CD4+, CD8+, and CD4+CD8+ T cells in a rat/mouse xenogeneic co-culture. A significant decrease in the same precursor cells, as well as a decrease in CD4-CD8- T cell precursors, was also observed in a murine C57BL/6 FTOC after rotation in a clinostat to produce a vector-averaged microgravity-like environment. The block in T cell development appeared to occur between the pre-T cell and CD4+CD8+ T cell stage. These data indicate that gravity plays a decisive role in the development of T cells.

Partial reconstitution of the CD4+-T-cell compartment in CD4 gene knockout mice restores responses to tuberculosis DNA vaccines.

PubMed

D'Souza, Sushila; Romano, Marta; Korf, Johanna; Wang, Xiao-Ming; Adnet, Pierre-Yves; Huygen, Kris

2006-05-01

Reactivation tuberculosis (TB) is a serious problem in immunocompromised individuals, especially those with human immunodeficiency virus (HIV) coinfection. The adaptive immune response mediated by CD4+ and CD8+ T cells is known to confer protection against TB. Hence, vaccines against TB are designed to activate these two components of the immune system. Anti-TB DNA vaccines encoding the immunodominant proteins Ag85A, Ag85B, and PstS-3 from Mycobacterium tuberculosis are ineffective in mice lacking CD4+ T cells (CD4-/- mice). In this study, we demonstrate that reconstitution of the T-cell compartment in CD4-/- mice restores vaccine-specific antibody and gamma interferon (IFN-gamma) responses to these DNA vaccines. The magnitude of the immune responses correlated with the extent of reconstitution of the CD4+-T-cell compartment. Reconstituted mice vaccinated with DNA encoding PstS-3, known to encode a dominant D(b)-restricted CD8+-T-cell epitope, displayed CD8+-T-cell responses not observed in CD4-/- mice. M. tuberculosis challenge in reconstituted mice led to the extravasation of IFN-gamma-producing CD4+ and CD8+ T cells into lungs, the primary site of bacterial replication. Importantly, a reconstitution of 12 to 15% of the CD4+-T-cell compartment resulted in Ag85B plasmid DNA-mediated protection against a challenge M. tuberculosis infection. Our findings provide evidence that anti-TB DNA vaccines could be effective in immunodeficient individuals after CD4+-T-lymphocyte reconstitution, as may occur following antiretroviral therapy in HIV+ patients.

Identification of a CD8 T cell that can independently mediate autoimmune diabetes development in the complete absence of CD4 T cell helper functions.

PubMed

Graser, R T; DiLorenzo, T P; Wang, F; Christianson, G J; Chapman, H D; Roopenian, D C; Nathenson, S G; Serreze, D V

2000-04-01

Previous work has indicated that an important component for the initiation of autoimmune insulin-dependent diabetes mellitus (IDDM) in the NOD mouse model entails MHC class I-restricted CD8 T cell responses against pancreatic beta cell Ags. However, unless previously activated in vitro, such CD8 T cells have previously been thought to require helper functions provided by MHC class II-restricted CD4 T cells to exert their full diabetogenic effects. In this study, we show that IDDM development is greatly accelerated in a stock of NOD mice expressing TCR transgenes derived from a MHC class I-restricted CD8 T cell clone (designated AI4) previously found to contribute to the earliest preclinical stages of pancreatic beta cell destruction. Importantly, these TCR transgenic NOD mice (designated NOD.AI4alphabeta Tg) continued to develop IDDM at a greatly accelerated rate when residual CD4 helper T cells were eliminated by introduction of the scid mutation or a functionally inactivated CD4 allele. In a previously described stock of NOD mice expressing TCR transgenes derived from another MHC class I-restricted beta cell autoreactive T cell clone, IDDM development was retarded by elimination of residual CD4 T cells. Hence, there is variability in the helper dependence of CD8 T cells contributing to the development of autoimmune IDDM. The AI4 clonotype represents the first CD8 T cell with a demonstrated ability to progress from a naive to functionally activated state and rapidly mediate autoimmune IDDM development in the complete absence of CD4 T cell helper functions.

Calcineurin B in CD4+ T Cells Prevents Autoimmune Colitis by Negatively Regulating the JAK/STAT Pathway.

PubMed

Mencarelli, Andrea; Vacca, Maurizio; Khameneh, Hanif Javanmard; Acerbi, Enzo; Tay, Alicia; Zolezzi, Francesca; Poidinger, Michael; Mortellaro, Alessandra

2018-01-01

Calcineurin (Cn) is a protein phosphatase that regulates the activation of the nuclear factor of activated T-cells (NFAT) family of transcription factors, which are key regulators of T-cell development and function. Here, we generated a conditional Cnb1 mouse model in which Cnb1 was specifically deleted in CD4 + T cells (Cnb1 CD4 mice) to delineate the role of the Cn-NFAT pathway in immune homeostasis of the intestine. The Cnb1 CD4 mice developed severe, spontaneous colitis characterized at the molecular level by an increased T helper-1-cell response but an unaltered regulatory T-cell compartment. Antibiotic treatment ameliorated the intestinal inflammation observed in Cnb1 CD4 mice, suggesting that the microbiota contributes to the onset of colitis. CD4 + T cells isolated from Cnb1 CD4 mice produced high levels of IFNγ due to increased activation of the JAK2/STAT4 pathway induced by IL-12. Our data highlight that Cn signaling in CD4 + T cells is critical for intestinal immune homeostasis in part by inhibiting IL-12 responsiveness of CD4 + T cells.

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

PubMed Central

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

2012-01-01

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

CD147 (Basigin/Emmprin) identifies FoxP3+CD45RO+CTLA4+-activated human regulatory T cells.

PubMed

Solstad, Therese; Bains, Simer Jit; Landskron, Johannes; Aandahl, Einar Martin; Thiede, Bernd; Taskén, Kjetil; Torgersen, Knut Martin

2011-11-10

Human CD4(+)FoxP3(+) T cells are functionally and phenotypically heterogeneous providing plasticity to immune activation and regulation. To better understand the functional dynamics within this subset, we first used a combined strategy of subcellular fractionation and proteomics to describe differences at the protein level between highly purified human CD4(+)CD25(+) and CD4(+)CD25(-) T-cell populations. This identified a set of membrane proteins highly expressed on the cell surface of human regulatory T cells (Tregs), including CD71, CD95, CD147, and CD148. CD147 (Basigin or Emmprin) divided CD4(+)CD25(+) cells into distinct subsets. Furthermore, CD147, CD25, FoxP3, and in particular CTLA-4 expression correlated. Phenotypical and functional analyses suggested that CD147 marks the switch between resting (CD45RA(+)) and activated (CD45RO(+)) subsets within the FoxP3(+) T-cell population. Sorting of regulatory T cells into CD147(-) and CD147(+) populations demonstrated that CD147 identifies an activated and highly suppressive CD45RO(+) Treg subset. When analyzing CD4(+) T cells for their cytokine producing potential, CD147 levels grouped the FoxP3(+) subset into 3 categories with different ability to produce IL-2, TNF-α, IFN-γ, and IL-17. Together, this suggests that CD147 is a direct marker for activated Tregs within the CD4(+)FoxP3(+) subset and may provide means to manipulate cells important for immune homeostasis.

The Development of Plasmodium falciparum-Specific IL10 CD4 T Cells and Protection from Malaria in Children in an Area of High Malaria Transmission.

PubMed

Boyle, Michelle J; Jagannathan, Prasanna; Bowen, Katherine; McIntyre, Tara I; Vance, Hilary M; Farrington, Lila A; Schwartz, Alanna; Nankya, Felistas; Naluwu, Kate; Wamala, Samuel; Sikyomu, Esther; Rek, John; Greenhouse, Bryan; Arinaitwe, Emmanuel; Dorsey, Grant; Kamya, Moses R; Feeney, Margaret E

2017-01-01

Cytokine-producing CD4 T cells have important roles in immunity against Plasmodium falciparum (Pf) malaria. However, the factors influencing functional differentiation of Pf- specific CD4 T cells in naturally exposed children are not well understood. Moreover, it is not known which CD4 T-cell cytokine-producing subsets are most critical for protection. We measured Pf- specific IFNγ-, IL10-, and TNFα-producing CD4 T-cell responses by multi-parametric flow cytometry in 265 children aged 6 months to 10 years enrolled in a longitudinal observational cohort in a high malaria transmission site in Uganda. We found that both age and parasite burden were independently associated with cytokine production by CD4 T cells. IL10 production by IFNγ + CD4 T cells was higher in younger children and in those with high-parasite burden during recent infection. To investigate the role of CD4 T cells in immunity to malaria, we measured associations of Pf -specific CD4 cytokine-producing cells with the prospective risk of Pf infection and clinical malaria, adjusting for household exposure to Pf -infected mosquitos. Overall, the prospective risk of infection was not associated with the total frequency of Pf- specific CD4 T cells, nor of any cytokine-producing CD4 subset. However, the frequency of CD4 cells producing IL10 but not inflammatory cytokines (IFNγ and TNFα) was associated with a decreased risk of clinical malaria once infected. These data suggest that functional polarization of the CD4 T-cell response may modulate the clinical manifestations of malaria and play a role in naturally acquired immunity.

Clonal expansion of genome-intact HIV-1 in functionally polarized Th1 CD4+ T cells

PubMed Central

Orlova-Fink, Nina; Einkauf, Kevin; Chowdhury, Fatema Z.; Sun, Xiaoming; Harrington, Sean; Kuo, Hsiao-Hsuan; Hua, Stephane; Chen, Hsiao-Rong; Ouyang, Zhengyu; Reddy, Kavidha; Dong, Krista; Ndung’u, Thumbi; Walker, Bruce D.; Rosenberg, Eric S.; Yu, Xu G.

2017-01-01

HIV-1 causes a chronic, incurable disease due to its persistence in CD4+ T cells that contain replication-competent provirus, but exhibit little or no active viral gene expression and effectively resist combination antiretroviral therapy (cART). These latently infected T cells represent an extremely small proportion of all circulating CD4+ T cells but possess a remarkable long-term stability and typically persist throughout life, for reasons that are not fully understood. Here we performed massive single-genome, near-full-length next-generation sequencing of HIV-1 DNA derived from unfractionated peripheral blood mononuclear cells, ex vivo-isolated CD4+ T cells, and subsets of functionally polarized memory CD4+ T cells. This approach identified multiple sets of independent, near-full-length proviral sequences from cART-treated individuals that were completely identical, consistent with clonal expansion of CD4+ T cells harboring intact HIV-1. Intact, near-full-genome HIV-1 DNA sequences that were derived from such clonally expanded CD4+ T cells constituted 62% of all analyzed genome-intact sequences in memory CD4 T cells, were preferentially observed in Th1-polarized cells, were longitudinally detected over a duration of up to 5 years, and were fully replication- and infection-competent. Together, these data suggest that clonal proliferation of Th1-polarized CD4+ T cells encoding for intact HIV-1 represents a driving force for stabilizing the pool of latently infected CD4+ T cells. PMID:28628034

Clonal expansion of genome-intact HIV-1 in functionally polarized Th1 CD4+ T cells.

PubMed

Lee, Guinevere Q; Orlova-Fink, Nina; Einkauf, Kevin; Chowdhury, Fatema Z; Sun, Xiaoming; Harrington, Sean; Kuo, Hsiao-Hsuan; Hua, Stephane; Chen, Hsiao-Rong; Ouyang, Zhengyu; Reddy, Kavidha; Dong, Krista; Ndung'u, Thumbi; Walker, Bruce D; Rosenberg, Eric S; Yu, Xu G; Lichterfeld, Mathias

2017-06-30

HIV-1 causes a chronic, incurable disease due to its persistence in CD4+ T cells that contain replication-competent provirus, but exhibit little or no active viral gene expression and effectively resist combination antiretroviral therapy (cART). These latently infected T cells represent an extremely small proportion of all circulating CD4+ T cells but possess a remarkable long-term stability and typically persist throughout life, for reasons that are not fully understood. Here we performed massive single-genome, near-full-length next-generation sequencing of HIV-1 DNA derived from unfractionated peripheral blood mononuclear cells, ex vivo-isolated CD4+ T cells, and subsets of functionally polarized memory CD4+ T cells. This approach identified multiple sets of independent, near-full-length proviral sequences from cART-treated individuals that were completely identical, consistent with clonal expansion of CD4+ T cells harboring intact HIV-1. Intact, near-full-genome HIV-1 DNA sequences that were derived from such clonally expanded CD4+ T cells constituted 62% of all analyzed genome-intact sequences in memory CD4 T cells, were preferentially observed in Th1-polarized cells, were longitudinally detected over a duration of up to 5 years, and were fully replication- and infection-competent. Together, these data suggest that clonal proliferation of Th1-polarized CD4+ T cells encoding for intact HIV-1 represents a driving force for stabilizing the pool of latently infected CD4+ T cells.

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 immunological synapse together with the T cell receptor and enhances the T cell receptor-induced activation of CD4 T cells. Heightened cellular activation promotes the capacity of CD4 T cells to support productive HIV replication. This study provides evidence of the exploitation of the normal immunological synapse and T cell activation process by HIV to boost the activation state of targeted CD4 T cells and promote the infection of these cells. PMID:27630246

Eomesodermin(lo) CTLA4(hi) Alloreactive CD8+ Memory T Cells Are Associated With Prolonged Renal Transplant Survival Induced by Regulatory Dendritic Cell Infusion in CTLA4 Immunoglobulin-Treated Nonhuman Primates.

PubMed

Ezzelarab, Mohamed B; Lu, Lien; Guo, Hao; Zahorchak, Alan F; Shufesky, William F; Cooper, David K C; Morelli, Adrian E; Thomson, Angus W

2016-01-01

Memory T cells (Tmem), particularly those resistant to costimulation blockade (CB), are a major barrier to transplant tolerance. The transcription factor Eomesodermin (Eomes) is critical for Tmem development and maintenance, but its expression by alloactivated T cells has not been examined in nonhuman primates. We evaluated Eomes and coinhibitory cytotoxic T lymphocyte antigen-4 (CTLA4) expression by alloactivated rhesus monkey T cells in the presence of CTLA4 immunoglobulin, both in vitro and in renal allograft recipients treated with CTLA4Ig, with or without regulatory dendritic cell (DCreg) infusion. In normal monkeys, CD8+ T cells expressed significantly more Eomes than CD4+ T cells. By contrast, CD8+ T cells displayed minimal CTLA4. Among T cell subsets, central Tmem (Tcm) expressed the highest levels of Eomes. Notably, Eomes(lo)CTLA4(hi) cells displayed higher levels of CD25 and Foxp3 than Eomes(hi)CTLA4(lo) CD8+ T cells. After allostimulation, distinct proliferating Eomes(lo)CTLA4(hi) and Eomes(hi)CTLA4(lo) CD8+ T cell populations were identified, with a high proportion of Tcm being Eomes(lo)CTLA4(hi). CB with CTLA4Ig during allostimulation of CD8+ T cells reduced CTLA4 but not Eomes expression, significantly reducing Eomes(lo)CTLA4(hi) cells. After transplantation with CB and rapamycin, donor-reactive Eomes(lo)CTLA4(hi) CD8+ T cells were reduced. However, in monkeys also given DCreg, absolute numbers of these cells were elevated significantly. Low Eomes and high CTLA4 expression by donor-reactive CD8+ Tmem is associated with prolonged renal allograft survival induced by DCreg infusion in CTLA4Ig-treated monkeys. Prolonged allograft survival associated with DCreg infusion may be related to maintenance of donor-reactive Eomes(lo)CTLA4(hi) Tcm.

Eomesoderminlo CTLA4hi Alloreactive CD8+ Memory T Cells Are Associated With Prolonged Renal Transplant Survival Induced by Regulatory Dendritic Cell Infusion in CTLA4Ig-Treated Non-Human Primates

PubMed Central

Ezzelarab, Mohamed B.; Lu, Lien; Guo, Hao; Zahorchak, Alan F.; Shufesky, William F.; Cooper, David K.C.; Morelli, Adrian E.; Thomson, Angus W.

2015-01-01

Background Memory T cells (Tmem), particularly those resistant to costimulation blockade (CB), are a major barrier to transplant tolerance. The transcription factor Eomesodermin (Eomes) is critical for Tmem development and maintenance, but its expression by alloactivated T cells has not been examined in non-human primates. Methods We evaluated Eomes and co-inhibitory cytotoxic T lymphocyte antigen-4 (CTLA4) expression by alloactivated rhesus monkey T cells in the presence of CTLA4 immunoglobulin (Ig), both in vitro and in renal allograft recipients treated with CTLA4Ig, with or without regulatory dendritic cell (DCreg) infusion. Results In normal monkeys, CD8+ T cells expressed significantly more Eomes than CD4+T cells. By contrast, CD8+T cells displayed minimal CTLA4. Among T cell subsets, central Tmem (Tcm) expressed the highest levels of Eomes. Notably, EomesloCTLA4hi cells displayed higher levels of CD25 and Foxp3 than EomeshiCTLA4lo CD8+ T cells. Following allostimulation, distinct proliferating EomesloCTLA4hi and EomeshiCTLA4lo CD8+ T cell populations were identified, with a high proportion of Tcm being EomesloCTLA4hi. CB with CTLA4Ig during allostimulation of CD8+T cells reduced CTLA4 but not Eomes expression, significantly reducing EomesloCTLA4hi cells. After transplantation with CB and rapamycin, donor-reactive EomesloCTLA4hi CD8+T cells were reduced. However, in monkeys also given DCreg, absolute numbers of these cells were elevated significantly. Conclusions Low Eomes and high CTLA4 expression by donor-reactive CD8+ Tmem is associated with prolonged renal allograft survival induced by DCreg infusion in CTLA4Ig-treated monkeys. Prolonged allograft survival associated with DCreg infusion may be related to maintenance of donor-reactive EomesloCTLA4hi Tcm. PMID:26680373

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.

Evidence for naive T-cell repopulation despite thymus irradiation after autologous transplantation in adults with multiple myeloma: role of ex vivo CD34+ selection and age.

PubMed

Malphettes, Marion; Carcelain, Guislaine; Saint-Mezard, Pierre; Leblond, Véronique; Altes, Hester Korthals; Marolleau, Jean-Pierre; Debré, Patrice; Brouet, Jean-Claude; Fermand, Jean-Paul; Autran, Brigitte

2003-03-01

Immunodeficiency following autologous CD34+-purified peripheral blood stem cell (PBSC) transplantation could be related to T-cell depletion of the graft or impaired T-cell reconstitution due to thymus irradiation. Aiming to assess the role of irradiated thymus in T-cell repopulation, we studied 32 adults with multiple myeloma, randomly assigned to receive high-dose therapy including total body irradiation (TBI) followed by autologous transplantation with either unselected or CD34+-selected PBSCs. The median number of reinfused CD3+ cells was lower in the selected group (0.03 versus 14 x 10(6)/kg; P =.002). Lymphocyte subset counts were evaluated from month 3 to 24 after grafting. Naive CD4+ T cells were characterized both by phenotype and by quantification of T-cell receptor rearrangement excision circles (TRECs). The reconstitution of CD3+ and CD4+ T cells was significantly delayed in the CD34+-selected group, but eventually led to counts similar to those found in the unselected group after month 12. Mechanism of reconstitution differed, however, between both groups. Indeed, a marked increase in the naive CD62L+CD45RA+CD4+ subset was observed in the selected group, but not in the unselected group in which half of the CD45RA+CD4+ T cells appear to be CD62L-. Age was identified as an independent adverse factor for CD4+ and CD62L+CD45RA+CD4+ T-cell reconstitution. Our results provide evidence that infusing PBSCs depleted of T cells after TBI in adults delays T-cell reconstitution but accelerates thymic regeneration.

Effector CD4+ T cells recognize intravascular antigen presented by patrolling monocytes.

PubMed

Westhorpe, Clare L V; Norman, M Ursula; Hall, Pam; Snelgrove, Sarah L; Finsterbusch, Michaela; Li, Anqi; Lo, Camden; Tan, Zhe Hao; Li, Songhui; Nilsson, Susan K; Kitching, A Richard; Hickey, Michael J

2018-02-21

Although effector CD4 + T cells readily respond to antigen outside the vasculature, how they respond to intravascular antigens is unknown. Here we show the process of intravascular antigen recognition using intravital multiphoton microscopy of glomeruli. CD4 + T cells undergo intravascular migration within uninflamed glomeruli. Similarly, while MHCII is not expressed by intrinsic glomerular cells, intravascular MHCII-expressing immune cells patrol glomerular capillaries, interacting with CD4 + T cells. Following intravascular deposition of antigen in glomeruli, effector CD4 + T-cell responses, including NFAT1 nuclear translocation and decreased migration, are consistent with antigen recognition. Of the MHCII + immune cells adherent in glomerular capillaries, only monocytes are retained for prolonged durations. These cells can also induce T-cell proliferation in vitro. Moreover, monocyte depletion reduces CD4 + T-cell-dependent glomerular inflammation. These findings indicate that MHCII + monocytes patrolling the glomerular microvasculature can present intravascular antigen to CD4 + T cells within glomerular capillaries, leading to antigen-dependent inflammation.

An epitope-specific DerG-PG70 LEAPS vaccine modulates T cell responses and suppresses arthritis progression in two related murine models of rheumatoid arthritis

PubMed Central

Mikecz, Katalin; Glant, Tibor T.; Markovics, Adrienn; Rosenthal, Kenneth S.; Kurko, Julia; Carambula, Roy E.; Cress, Steve; Steiner, Harold L.; Zimmerman, Daniel H.

2017-01-01

Rheumatoid arthritis (RA) is an autoimmune joint disease maintained by aberrant immune responses involving CD4+ T helper (Th)1 and Th17 cells. In this study, we tested the therapeutic efficacy of Ligand Epitope Antigen Presentation System (LEAPS™) vaccines in two Th1 cell-driven mouse models of RA, cartilage proteoglycan (PG)-induced arthritis (PGIA) and PG G1-domain-induced arthritis (GIA). The immunodominant PG peptide PG70 was attached to a DerG or J immune cell binding peptide, and the DerG-PG70 and J-PG70 LEAPS vaccines were administered to the mice after the onset of PGIA or GIA symptoms. As indicated by significant decreases in visual and histopathological scores of arthritis, the DerG-PG70 vaccine inhibited disease progression in both PGIA and GIA, while the J-PG70 vaccine was ineffective. Splenic CD4+ cells from DerG-PG70-treated mice were diminished in Th1 and Th17 populations but enriched in Th2 and regulatory T (Treg) cells. In vitro spleen cell-secreted and serum cytokines from DerG-PG70-treated mice demonstrated a shift from a pro-inflammatory to an anti-inflammatory/regulatory profile. DerG-PG70 peptide tetramers preferentially bound to CD4+ T-cells of GIA spleen cells. We conclude that the DerG-PG70 vaccine (now designated CEL-4000) exerts its therapeutic effect by interacting with CD4+ cells, which results in an antigen-specific down-modulation of pathogenic T-cell responses in both the PGIA and GIA models of RA. Future studies will need to determine the potential of LEAPS vaccination to provide disease suppression in patients with RA. PMID:28583308

NAD+ protects against EAE by regulating CD4+ T-cell differentiation

PubMed Central

Tullius, Stefan G.; Biefer, Hector Rodriguez Cetina; Li, Suyan; Trachtenberg, Alexander J.; Edtinger, Karoline; Quante, Markus; Krenzien, Felix; Uehara, Hirofumi; Yang, Xiaoyong; Kissick, Haydn T.; Kuo, Winston P.; Ghiran, Ionita; de la Fuente, Miguel A.; Arredouani, Mohamed S.; Camacho, Virginia; Tigges, John C.; Toxavidis, Vasilis; El Fatimy, Rachid; Smith, Brian D.; Vasudevan, Anju; ElKhal, Abdallah

2014-01-01

CD4+ T cells are involved in the development of autoimmunity, including multiple sclerosis (MS). Here we show that nicotinamide adenine dinucleotide (NAD+) blocks experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, by inducing immune homeostasis through CD4+IFNγ+IL-10+ T cells and reverses disease progression by restoring tissue integrity via remyelination and neuroregeneration. We show that NAD+ regulates CD4+ T-cell differentiation through tryptophan hydroxylase-1 (Tph1), independently of well-established transcription factors. In the presence of NAD+, the frequency of T-bet−/− CD4+IFNγ+ T cells was twofold higher than wild-type CD4+ T cells cultured in conventional T helper 1 polarizing conditions. Our findings unravel a new pathway orchestrating CD4+ T-cell differentiation and demonstrate that NAD+ may serve as a powerful therapeutic agent for the treatment of autoimmune and other diseases. PMID:25290058

Co-expression of LAG3 and TIM3 identifies a potent Treg population that suppresses macrophage functions in colorectal cancer patients.

PubMed

Ma, Qiang; Liu, Junning; Wu, Guoliang; Teng, Mujian; Wang, Shaoxuan; Cui, Meng; Li, Yuantao

2018-06-15

Regulatory T (Treg) cells are critical suppressors of inflammation and are thought to exert mainly deleterious effects in cancers. In colorectal cancer (CRC), Foxp3 +  Treg accumulation in the tumor was associated with poor prognosis. Hence, we examined the circulating Treg cells in CRC patients. Compared to controls, CRC patients presented mild upregulations in CD4 + CD25 +/hi T cells and in the more canonical CD4 + CD25 +/hi Foxp3 + Treg cells in peripheral blood mononuclear cells. Both of these Treg populations could be roughly divided into LAG3 - TIM3 - and LAG3 + TIM3 + subsets. In CRC patients, the LAG3 + TIM3 + subset represented approximately half of CD4 + CD25 +/hi T cells and greater than 60% of CD4 + CD25 +/hi Foxp3 + Treg cells, which was significantly more frequent than in healthy controls. Compared to the LAG3 - TIM3 - CD4 + CD25 +/hi T cells, the LAG3 + TIM3 + CD4 + CD25 +/hi T cells presented considerably higher transforming growth factor (TGF)-β and slightly higher interleukin (IL)-10 secretion, together with higher CTLA-4 and Foxp3 expression levels. Notably, macrophages following incubation with LAG3 - TIM3 - CD4 + CD25 +/hi T cells and LAG3 + TIM3 + CD4 + CD25 +/hi T cells displayed different characteristics. Macrophages incubated with LAG3 + TIM3 + CD4 + CD25 +/hi T cells presented lower expression of MHC class II, CD80, CD86, and tumor necrosis factor alpha (TNFα) but higher expression of IL-10, than macrophages incubated with LAG3 - TIM3 - CD4 + CD25 +/hi T cells. Together, our investigations demonstrated that CRC patients presented an enrichment of circulating Treg cells, in which the LAG3 + TIM3 + subset exhibited more potent expression of inhibitory molecules, and furthermore, the LAG3 + TIM3 + Treg cells could suppress the proinflammatory activation of macrophages more potently than the LAG3 - TIM3 - Treg cells. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

CD4+ Foxp3+ T-cells contribute to myocardial ischemia-reperfusion injury.

PubMed

Mathes, Denise; Weirather, Johannes; Nordbeck, Peter; Arias-Loza, Anahi-Paula; Burkard, Matthias; Pachel, Christina; Kerkau, Thomas; Beyersdorf, Niklas; Frantz, Stefan; Hofmann, Ulrich

2016-12-01

The present study analyzed the effect of CD4 + Forkhead box protein 3 negative (Foxp3 - ) T-cells and Foxp3 + CD4 + T-cells on infarct size in a mouse myocardial ischemia-reperfusion model. We examined the infarct size as a fraction of the area-at-risk as primary study endpoint in mice after 30minutes of coronary ligation followed by 24hours of reperfusion. CD4 + T-cell deficient MHC-II KO mice showed smaller histologically determined infarct size (34.5±4.7% in MHCII KO versus 59.4±4.9% in wildtype (WT)) and better preserved ejection fraction determined by magnetic resonance tomography (56.9±2.8% in MHC II KO versus 39.0±4.2% in WT). MHC-II KO mice also displayed better microvascular perfusion than WT mice after 24hours of reperfusion. Also CD4 + T-cell sufficient OT-II mice, which express an in this context irrelevant T-cell receptor, revealed smaller infarct sizes compared to WT mice. However, MHC-II blocking anti-I-A/I-E antibody treatment was not able to reduce infarct size indicating that autoantigen recognition is not required for the activation of CD4 + T-cells during reperfusion. Flow-cytometric analysis also did not detect CD4 + T-cell activation in heart draining lymph nodes in response to 24hours of ischemia-reperfusion. Adoptive transfer of CD4 + T-cells in CD4 KO mice increased the infarct size only when including the Foxp3 + CD25 + subset. Depletion of CD4 + Foxp3 + T-cells in DEREG mice enabling specific conditional ablation of this subset by treatment with diphtheria toxin attenuated infarct size as compared to diphtheria toxin treated WT mice. CD4 + Foxp3 + T-cells enhance myocardial ischemia-reperfusion injury. CD4 + T-cells exert injurious effects without the need for prior activation by MHC-II restricted autoantigen recognition. Copyright © 2016 Elsevier Ltd. All rights reserved.

IL-7 signaling imparts polyfunctionality and stemness potential to CD4+ T cells

PubMed Central

Ding, Zhi-Chun; Liu, Chufeng; Cao, Yang; Habtetsion, Tsadik; Kuczma, Michal; Pi, Wenhu; Kong, Heng; Cacan, Ercan; Greer, Susanna F.; Cui, Yan; Blazar, Bruce R.; Munn, David H.; Zhou, Gang

2016-01-01

ABSTRACT The functional status of CD4+ T cells is a critical determinant of antitumor immunity. Polyfunctional CD4+ T cells possess the ability to concomitantly produce multiple Th1-type cytokines, exhibiting a functional attribute desirable for cancer immunotherapy. However, the mechanisms by which these cells are induced are neither defined nor it is clear if these cells can be used therapeutically to treat cancer. Here, we report that CD4+ T cells exposed to exogenous IL-7 during antigenic stimulation can acquire a polyfunctional phenotype, characterized by their ability to simultaneously express IFNγ, IL-2, TNFα and granzyme B. This IL-7-driven polyfunctional phenotype was associated with increased histone acetylation in the promoters of the effector genes, indicative of increased chromatin accessibility. Moreover, forced expression of a constitutively active (CA) form of STAT5 recapitulated IL-7 in inducing CD4+ T-cell polyfunctionality. Conversely, the expression of a dominant negative (DN) form of STAT5 abolished the ability of IL-7 to induce polyfunctional CD4+ T cells. These in-vitro-generated polyfunctional CD4+ T cells can traffic to tumor and expand intratumorally in response to immunization. Importantly, adoptive transfer of polyfunctional CD4+ T cells following lymphodepletive chemotherapy was able to eradicate large established tumors. This beneficial outcome was associated with the occurrence of antigen epitope spreading, activation of the endogenous CD8+ T cells and persistence of donor CD4+ T cells exhibiting memory stem cell attributes. These findings indicate that IL-7 signaling can impart polyfunctionality and stemness potential to CD4+ T cells, revealing a previously unknown property of IL-7 that can be exploited in adoptive T-cell immunotherapy. PMID:27471650

Human Immunodeficiency Virus Type-1 Elite Controllers Maintain Low Co-Expression of Inhibitory Receptors on CD4+ T Cells.

PubMed

Noyan, Kajsa; Nguyen, Son; Betts, Michael R; Sönnerborg, Anders; Buggert, Marcus

2018-01-01

Human immunodeficiency virus type-1 (HIV-1) elite controllers (ELCs) represent a unique population that control viral replication in the absence of antiretroviral therapy (cART). It is well established that expression of multiple inhibitory receptors on CD8+ T cells is associated with HIV-1 disease progression. However, whether reduced co-expression of inhibitory receptors on CD4+ T cells is linked to natural viral control and slow HIV-1 disease progression remains undefined. Here, we report on the expression pattern of numerous measurable inhibitory receptors, associated with T cell exhaustion (programmed cell death-1, CTLA-4, and TIGIT), on different CD4+ T cell memory populations in ELCs and HIV-infected subjects with or without long-term cART. We found that the co-expression pattern of inhibitory receptors was significantly reduced in ELCs compared with HIV-1 cART-treated and viremic subjects, and similar to healthy controls. Markers associated with T cell exhaustion varied among different memory CD4+ T cell subsets and highest levels were found mainly on transitional memory T cells. CD4+ T cells co-expressing all inhibitory markers were positively correlated to T cell activation (CD38+ HLA-DR+) as well as the transcription factors Helios and FoxP3. Finally, clinical parameters such as CD4 count, HIV-1 viral load, and the CD4/CD8 ratio all showed significant associations with CD4+ T cell exhaustion. We demonstrate that ELCs are able to maintain lower levels of CD4+ T cell exhaustion despite years of ongoing viral replication compared with successfully cART-treated subjects. Our findings suggest that ELCs harbor a "healthy" state of inhibitory receptor expression on CD4+ T cells that might play part in maintenance of their control status.

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

PubMed

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

2012-08-30

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

Localization of the T-cell response to RSV infection is altered in infant mice.

PubMed

Eichinger, Katherine M; Kosanovich, Jessica L; Empey, Kerry M

2018-02-01

Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infections worldwide, causing disproportionate morbidity and mortality in infants and children. Infants with stronger Th1 responses have less severe disease, yet little is known about the infant T-cell response within the air space. Thus, we tested the hypothesis that RSV infected infant mice would have quantitative and qualitative deficiencies in CD4 + and CD8 + T-cell populations isolated from the bronchoalveolar lavage when compared to adults and that local delivery of IFN-γ would increase airway CD4 + Tbet + and CD8 + Tbet + T-cell responses. We compared the localization of T-cell responses in RSV-infected infant and adult mice and investigated the effects of local IFN-γ administration on infant cellular immunity. Adult CD8 + CD44 HI and CD4 + CD44 HI Tbet + T-cells accumulated in the alveolar space whereas CD4 + CD44 HI Tbet + T-cells were evenly distributed between the infant lung tissue and airway and infant lungs contained higher frequencies of CD8 + T-cells. Delivery of IFN-γ to the infant airway failed to increase the accumulation of T-cells in the airspace and unexpectedly reduced CD4 + CD44 HI Tbet + T-cells. However, intranasal IFN-γ increased RSV F protein-specific CD8 + T-cells in the alveolar space. Together, these data suggest that quantitative and qualitative defects exist in the infant T-cell response to RSV but early, local IFN-γ exposure can increase the CD8 + RSV-specific T-cell response. © 2017 Wiley Periodicals, Inc.

IFNγ-producing CD4+ T lymphocytes: the double-edged swords in tuberculosis.

PubMed

Kumar, Pawan

2017-12-01

IFNγ-producing CD4 + T cells (IFNγ + CD4 + T cells) are the key orchestrators of protective immunity against Mycobacterium tuberculosis (Mtb). Primarily, these cells act by enabling Mtb-infected macrophages to enforce phagosome-lysosome fusion, produce reactive nitrogen intermediates (RNIs), and activate autophagy pathways. However, TB is a heterogeneous disease and a host of clinical and experimental findings has also implicated IFNγ + CD4 + T cells in TB pathogenesis. High frequency of IFNγ + CD4 + T cells is the most invariable feature of the active disease. Active TB patients mount a heightened IFNγ + CD4 + T cell response to mycobacterial antigens and demonstrate an IFNγ-inducible transcriptomic signature. IFNγ + CD4 + T cells have also been shown to mediate TB-associated immune reconstitution inflammatory syndrome (TB-IRIS) observed in a subset of antiretroviral therapy (ART)-treated HIV- and Mtb-coinfected people. The pathological face of IFNγ + CD4 + T cells during mycobacterial infection is further uncovered by studies in the animal model of TB-IRIS and in Mtb-infected PD-1 -/- mice. This manuscript encompasses the evidence supporting the dual role of IFNγ + CD4 + T cells during Mtb infection and sheds light on immune mechanisms involved in protection versus pathogenesis.

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

PubMed

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

2008-06-01

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

Assigning Cytomegalovirus (CMV) Status in Children Awaiting Organ Transplant: Viral Shedding, CMV-Specific T-cells and CD27-CD28-CD4+ T-cells.

PubMed

Burton, Catherine E; Sester, Martina; Robinson, Joan L; Eurich, Dean T; Preiksaitis, Jutta K; Urschel, Simon

2018-05-24

Passive antibodies, maternal or transfusion-acquired, make serologic determination of pre-transplant cytomegalovirus (CMV) status unreliable. We evaluated 3 assays un-affected by passive antibodies, in assignment of CMV infection status in children awaiting solid organ transplant and in controls: i) CMV Nucleic Acid Amplification Testing (NAAT), quantification of ii) CMV-specific CD4+T-cells, and iii) CD27-CD28-CD4+T-cells. Our results highlight that CMV NAAT, from urine and oropharynx, is useful in confirming positive CMV status. Detection of CMV-specific CD4+T-cells was sensitive and specific in children >18 months but was less sensitive in children <12 months. CD27-CD28- CD4+T-cells are not likely useful in CMV risk-stratification in children.

FoxP3+ CD25+ CD8+ T-Cell Induction during Primary Simian Immunodeficiency Virus Infection in Cynomolgus Macaques Correlates with Low CD4+ T-Cell Activation and High Viral Load▿

PubMed Central

Karlsson, Ingrid; Malleret, Benoît; Brochard, Patricia; Delache, Benoît; Calvo, Julien; Le Grand, Roger; Vaslin, Bruno

2007-01-01

The early immune response fails to prevent the establishment of chronic human immunodeficiency virus (HIV) infection but may influence viremia during primary infection, thereby possibly affecting long-term disease progression. CD25+ FoxP3+ regulatory T cells may contribute to HIV/simian immunodeficiency virus (SIV) pathogenesis by suppressing efficient antiviral responses during primary infection, favoring high levels of viral replication and the establishment of chronic infection. In contrast, they may decrease immune activation during chronic infection. CD4+ regulatory T cells have been studied in the most detail, but CD8+ CD25+ FoxP3+ T cells also have regulatory properties. We monitored the dynamics of CD25+ FoxP3+ T cells during primary and chronic SIVmac251 infection in cynomolgus macaques. The number of peripheral CD4+ CD25+ FoxP3+ T cells paralleled that of memory CD4+ T cells, with a rapid decline during primary infection followed by a rebound to levels just below baseline and gradual depletion during the course of infection. No change in the proportion of CD25+ FoxP3+ T cells was observed in peripheral lymph nodes. A small number of CD4+ CD25+ FoxP3+ T cells at set point was associated with a high plasma viral load. In contrast, peripheral CD8+ CD25+ FoxP3+ T cells were induced a few days after peak plasma viral load during primary infection. The number of these cells was positively correlated with viral load and negatively correlated with CD4+ T-cell activation, SIV antigen-specific proliferative responses during primary infection, and plasma viral load at set point, with large numbers of CD8+ CD25+ FoxP3+ T cells being indicative of a poor prognosis. PMID:17898053

Intracellular IL-4, IL-5, and IFN-γ as the main characteristic of CD4+CD30+ T cells after allergen stimulation in patients with vernal keratoconjunctivitis

PubMed Central

Magaña, Diana; Aguilar, Gustavo; Linares, Marisela; Ayala-Balboa, Julio; Santacruz, Concepción; Chávez, Raúl; Estrada-Parra, Sergio; Garfias, Yonathan; Lascurain, Ricardo; Jiménez-Martínez, Maria C.

2015-01-01

Background Vernal keratoconjunctivitis (VKC) is a severe form of allergic conjunctivitis, in which inflammatory infiltrates of the conjunctiva are characterized by CD3+ and CD30+ cells. Until today, the functional involvement of CD30+ T cells in VKC was unclear. Our aim was to evaluate the functional characteristics of CD30+ T cells after allergen stimulation in peripheral blood mononuclear cells obtained from patients with VKC. Methods Seventeen consecutive patients at the Institute of Ophthalmology with active forms of VKC were included. Results After allergen stimulation, we observed the frequency of CD30+ T cells increased compared with non-stimulated cells (p<0.0001). The CD30+ T cells responded to the specific allergen-inducing expression of intracellular interleukin-4 (IL-4), IL-5, and interferon-gamma (IFN-γ) compared with the CD30- T cells (p<0.0001). Increased early secretion of soluble CD30 was observed in the supernatant of the cultured cells from patients with keratoconjunctivitis, compared with healthy controls (p=0.03). Blockage with IL-4 significantly diminished CD30 frequency in the allergen-stimulated cells. Conclusions Our results suggest that after allergenic stimulation, CD4+CD30+ cells are the most important source of IL-4, IL-5, and IFN-γ. IL-4 acts as an activation loop that increases CD30 expression on T cells after specific stimulation. These findings suggest that CD4+CD30+ T cells are effector cells and play a significant role in the immune pathogenic response in patients with vernal keratoconjunctivitis. PMID:25999672

Cannabidiol (CBD) Induces Functional Tregs in Response to Low-Level T Cell Activation

PubMed Central

Dhital, Saphala; Stokes, John V.; Park, Nogi; Seo, Keun-Seok; Kaplan, Barbara L.F.

2016-01-01

Many effects of the non-psychoactive cannabinoid, cannabidiol (CBD), have been described in immune responses induced by strong immunological stimuli. It has also been shown that CBD enhances IL-2 production in response to low-level T cell stimulation. Since IL-2, in combination with TGF-β1, are critical for Treg induction, we hypothesized that CBD would induce CD4+CD25+FOXP3+ Tregs in response to low-level stimulation. Low-level T cell stimulation conditions were established based on minimal CD25 expression in CD4+ cells using suboptimal PMA/Io (4 nM/0.05 μM, S/o), ultrasuboptimal PMA/Io (1 nM/0.0125 μM, Us/o) or soluble anti-CD3/28 (400-800 ng each, s3/28). CBD increased CD25+FOXP3+ cells from CD4+, CD4+CD25+, and CD4+CD25− T cells, as well as in CD4+ T cells derived from FOXP3-GFP mice. Most importantly, the Us/o + CBD-induced CD4+CD25+ Tregs robustly suppressed responder T cell proliferation, demonstrating that the mechanism by which CBD is immunosuppressive under low-level T cell stimulation involves induction of functional Tregs. PMID:27865421

Cannabidiol (CBD) induces functional Tregs in response to low-level T cell activation.

PubMed

Dhital, Saphala; Stokes, John V; Park, Nogi; Seo, Keun Seok; Kaplan, Barbara L F

2017-02-01

Many effects of the non-psychoactive cannabinoid, cannabidiol (CBD), have been described in immune responses induced by strong immunological stimuli. It has also been shown that CBD enhances IL-2 production in response to low-level T cell stimulation. Since IL-2, in combination with TGF-β1, are critical for Treg induction, we hypothesized that CBD would induce CD4 + CD25 + FOXP3 + Tregs in response to low-level stimulation. Low-level T cell stimulation conditions were established based on minimal CD25 expression in CD4 + cells using suboptimal PMA/Io (4nM/0.05μM, S/o), ultrasuboptimal PMA/Io (1nM/0.0125μM, Us/o) or soluble anti-CD3/28 (400-800ng each, s3/28). CBD increased CD25 + FOXP3 + cells from CD4 + , CD4 + CD25 + , and CD4 + CD25 - T cells, as well as in CD4 + T cells derived from FOXP3-GFP mice. Most importantly, the Us/o+CBD-induced CD4 + CD25 + Tregs robustly suppressed responder T cell proliferation, demonstrating that the mechanism by which CBD is immunosuppressive under low-level T cell stimulation involves induction of functional Tregs. Copyright © 2016 Elsevier Inc. All rights reserved.

Fucosyltransferase Induction during Influenza Virus Infection Is Required for the Generation of Functional Memory CD4+ T Cells

PubMed Central

Carrette, Florent; Henriquez, Monique L.; Fujita, Yu

2018-01-01

T cells mediating influenza viral control are instructed in lymphoid and nonlymphoid tissues to differentiate into memory T cells that confer protective immunity. The mechanisms by which influenza virus–specific memory CD4+ T cells arise have been attributed to changes in transcription factors, cytokines and cytokine receptors, and metabolic programming. The molecules involved in these biosynthetic pathways, including proteins and lipids, are modified to varying degrees of glycosylation, fucosylation, sialation, and sulfation, which can alter their function. It is currently unknown how the glycome enzymatic machinery regulates CD4+ T cell effector and memory differentiation. In a murine model of influenza virus infection, we found that fucosyltransferase enzymatic activity was induced in effector and memory CD4+ T cells. Using CD4+ T cells deficient in the Fut4/7 enzymes that are expressed only in hematopoietic cells, we found decreased frequencies of effector cells with reduced expression of T-bet and NKG2A/C/E in the lungs during primary infection. Furthermore, Fut4/7−/− effector CD4+ T cells had reduced survival with no difference in proliferation or capacity for effector function. Although Fut4/7−/− CD4+ T cells seeded the memory pool after primary infection, they failed to form tissue-resident cells, were dysfunctional, and were unable to re-expand after secondary infection. Our findings highlight an important regulatory axis mediated by cell-intrinsic fucosyltransferase activity in CD4+ T cell effectors that ensure the development of functional memory CD4+ T cells. PMID:29491007

Analytical validation of quantitative immunohistochemical assays of tumor infiltrating lymphocyte biomarkers.

PubMed

Singh, U; Cui, Y; Dimaano, N; Mehta, S; Pruitt, S K; Yearley, J; Laterza, O F; Juco, J W; Dogdas, B

2018-06-04

Tumor infiltrating lymphocytes (TIL), especially T-cells, have both prognostic and therapeutic applications. The presence of CD8+ effector T-cells and the ratio of CD8+ cells to FOXP3+ regulatory T-cells have been used as biomarkers of disease prognosis to predict response to various immunotherapies. Blocking the interaction between inhibitory receptors on T-cells and their ligands with therapeutic antibodies including atezolizumab, nivolumab, pembrolizumab and tremelimumab increases the immune response against cancer cells and has shown significant improvement in clinical benefits and survival in several different tumor types. The improved clinical outcome is presumed to be associated with a higher tumor infiltration; therefore, it is thought that more accurate methods for measuring the amount of TIL could assist prognosis and predict treatment response. We have developed and validated quantitative immunohistochemistry (IHC) assays for CD3, CD8 and FOXP3 for immunophenotyping T-lymphocytes in tumor tissue. Various types of formalin fixed, paraffin embedded (FFPE) tumor tissues were immunolabeled with anti-CD3, anti-CD8 and anti-FOXP3 antibodies using an IHC autostainer. The tumor area of stained tissues, including the invasive margin of the tumor, was scored by a pathologist (visual scoring) and by computer-based quantitative image analysis. Two image analysis scores were obtained for the staining of each biomarker: the percent positive cells in the tumor area and positive cells/mm 2 tumor area. Comparison of visual vs. image analysis scoring methods using regression analysis showed high correlation and indicated that quantitative image analysis can be used to score the number of positive cells in IHC stained slides. To demonstrate that the IHC assays produce consistent results in normal daily testing, we evaluated the specificity, sensitivity and reproducibility of the IHC assays using both visual and image analysis scoring methods. We found that CD3, CD8 and FOXP3 IHC assays met the fit-for-purpose analytical acceptance validation criteria and that they can be used to support clinical studies.

IL-7Rαlow memory CD8+ T cells are significantly elevated in patients with systemic lupus erythematosus.

PubMed

Kim, Jung-Sik; Cho, Bon-A; Sim, Ji Hyun; Shah, Kamini; Woo, Connie M; Lee, Eun Bong; Lee, Dong-Sup; Kang, Jae Seung; Lee, Wang Jae; Park, Chung-Gyu; Craft, Joe; Kang, Insoo; Kim, Hang-Rae

2012-09-01

Human effector memory (EM) CD8(+) T cells include IL-7Rα(high) and IL-7Rα(low) cells with distinct cellular characteristics, including the expression of cytotoxic molecules. Both NK cells and the NK cell-associated molecule 2B4 that is expressed on CD8(+) T cells promote cytotoxicity. Here we analysed the expression of 2B4 on IL-7Rα(high) and IL-7Rα(low) EM CD8(+) T cells and its contribution to cytotoxicity. We also analysed the frequency of IL-7Rα(high) and IL-7Rα(low) EM CD8(+) T cells in patients with SLE or lupus and in healthy individuals given the potential role of cytotoxic CD8(+) T cells in the pathogenesis of lupus. We used flow cytometry to measure the expression of 2B4 on IL-7Rα(high) and IL-7Rα(low) EM CD8(+) T cells as well as the frequency of these cell populations in the peripheral blood of healthy individuals and patients with SLE. Also, 2B4-mediated cytotoxicity was quantitated in IL-7Rα(high) and IL-7Rα(low) EM CD8(+) T cells using target cells with CD48 antigen. We found that IL-7Rα(high) EM CD8(+) T cells had higher levels of 2B4 expression compared with IL-7Rα(low) EM CD8(+) T cells. Triggering 2B4 enhanced the cytotoxic function of IL-7Rα(low) EM CD8(+) T cells against target cells. We also noticed that patients with SLE had an increased frequency of IL-7Rα(low) EM CD8(+) T cells that correlated with disease manifestation. Our findings show that SLE patients have increased IL-7Rα(low) EM CD8(+) T cells, possibly contributing to tissue damage through 2B4-mediated cytotoxicity.

Circulating CD4+CD28null and extra-thymic CD4+CD8+ double positive T cells are independently associated with disease damage in systemic lupus erythematosus patients.

PubMed

Ugarte-Gil, M F; Sánchez-Zúñiga, C; Gamboa-Cárdenas, R V; Aliaga-Zamudio, M; Zevallos, F; Tineo-Pozo, G; Cucho-Venegas, J M; Mosqueira-Riveros, A; Medina, M; Perich-Campos, R A; Alfaro-Lozano, J L; Rodriguez-Bellido, Z; Alarcón, G S; Pastor-Asurza, C A

2016-03-01

To determine whether circulating CD4+CD28null and extra-thymic CD4+CD8+ double positive (DP) T cells are independently associated with damage accrual in systemic lupus erythematosus (SLE) patients. This cross-sectional study was conducted between September 2013 and April 2014 in consecutive SLE patients from our Rheumatology Department. CD4+CD28null and CD4+CD8+ DP T-cell frequencies were analyzed by flow-cytometry. The association of damage (SLICC/ACR Damage Index, SDI) and CD4+CD28null and CD4+CD8+ DP T cells was examined by univariable and multivariable Poisson regression models, adjusting for possible confounders. All analyses were performed using SPSS 21.0. Patients' (n = 133) mean (SD) age at diagnosis was 35.5 (16.8) years, 124 (93.2%) were female; all were mestizo (mixed Caucasian and Amerindian ancestry). Disease duration was 7.4 (6.8) years. The SLE Disease Activity Index was 5.5 (4.2), and the SDI 0.9 (1.2). The percentages of CD4+CD28null and CD4+CD8+ DP T cells were 17.1 (14.4) and 0.4 (1.4), respectively. The percentage of CD4+CD28null and CD4+CD8+ DP T cells were positively associated with a higher SDI in both univariable (rate ratio (RR) 1.02, 95% confidence interval (CI): 1.01-1.03 and 1.17, 95% CI: 1.07-1.27, respectively; p < 0.001 for both) and multivariable analyses RR 1.02, 95% CI: 1.01-1.03, p = 0.001 for CD4+CD28null T cells and 1.28, 95% CI: 1.13-1.44, p < 0.001 for CD4+CD8+ DP T cells). Only the renal domain remained associated with CD4+CD28null in multivariable analyses (RR 1.023 (1.002-1.045); p = 0.034). In SLE patients, CD4+CD28null and CD4+CD8+ DP T cells are independently associated with disease damage. Longitudinal studies are warranted to determine the predictive value of these associations. © The Author(s) 2015.

CD19+CD24hiCD38hiBregs involved in downregulate helper T cells and upregulate regulatory T cells in gastric cancer

PubMed Central

Wang, Weiwei; Yuan, Xiangliang; Chen, Hui; Xie, Guohua; Ma, Yanhui; Zheng, Yingxia; Zhou, Yunlan; Shen, Lisong

2015-01-01

Regulatory B cells (Bregs) play a critical role in inflammation and autoimmune disease. We characterized the role of Bregs in the progression of gastric cancer. We detected an increase in Bregs producing IL-10 both in peripheral blood mononuclear cells (PBMCs) and in gastric tumors. Multicolor flow cytometry analysis revealed that a subset of CD19+CD24hiCD38hi B cells produces IL-10. Functional studies indicated that increased Bregs do not inhibit the proliferation of CD3+T cells or CD4+ helper T cells (Th cells). However, Bregs do suppress the secretion of IFN-γ and TNF-α by CD4+Th cells. CD19+CD24hiCD38hiBregs were also found to correlate positively with CD4+FoxP3+ regulatory T cells (Tregs). Neutralization experiments showed that Bregs convert CD4+CD25− effector T cells to CD4+FoxP3+Tregs via TGF-β1. Collectively, these findings demonstrate that increased Bregs play a immunosuppressive role in gastric cancer by inhibiting T cells cytokines as well as conversion to Tregs. These results may provide new clues about the underlying mechanisms of immune escape in gastric cancer. PMID:26378021

The effects of anti-Fas ribozyme on T lymphocyte apoptosis in mice model with chronic obstructive pulmonary disease.

PubMed

Zhuo, Song-Ming; Li, Si-Cong; Lin, Yong-Qun; Yu, Hai-Bin; Li, Na

2017-10-01

In this study, we aimed to investigate the effects of anti-Fas ribozyme on the apoptosis of T lymphocytes (T cells) in mice model with chronic obstructive pulmonary disease (COPD). Male 6-week-old C57BL/6 mice were used to establish the COPD model by exposure to cigarette smoke. The COPD mice were sacrificed for spleen dissection and T cell isolation. T cells were randomly divided into four groups (n=10 per group). Group A was used as the control. B, C, and D groups were transfected with empty lentivirus, anti-Fas ribozyme, and an anti-Fas ribozyme mutant, respectively. The expression of Fas mRNA and protein in the T cells were evaluated using qPCR and Western blot, respectively. Flow cytometry was used to evaluate the apoptosis of CD 4+ T cells and calculate the ratio of CD 4+ to CD 8+ T cells (CD 4+ /CD 8+ ). Anti-Fas ribozyme significantly inhibited the expression of Fas in the T cells of COPD mice. In addition, the number of apoptotic CD 4+ T cells and CD 4+ /CD 8+ of the C and D groups were significantly lower and higher than those of group A, respectively ( P <0.05). The apoptotic CD 4+ T cells and CD 4+ CD 8+ of the C group were significantly lower and higher than those of group D, respectively ( P <0.05). Anti-Fas ribozyme significantly inhibited the expression of Fas, increased CD 4+ /CD 8+ , and inhibited the apoptosis of T cells in COPD mice.

Chronic Exposure to Type-I IFN under Lymphopenic Conditions Alters CD4 T Cell Homeostasis

PubMed Central

Le Saout, Cecile; Hasley, Rebecca B.; Imamichi, Hiromi; Tcheung, Lueng; Hu, Zonghui; Luckey, Megan A.; Park, Jung-Hyun; Durum, Scott K.; Smith, Mindy; Rupert, Adam W.; Sneller, Michael C.; Lane, H. Clifford; Catalfamo, Marta

2014-01-01

HIV infection and the associated chronic immune activation alter T cell homeostasis leading to CD4 T cell depletion and CD8 T cell expansion. The mechanisms behind these outcomes are not totally defined and only partially explained by the direct cytopathic effect of the virus. In this manuscript, we addressed the impact of lymphopenia and chronic exposure to IFN-α on T cell homeostasis. In a lymphopenic murine model, this interaction led to decreased CD4 counts and CD8 T cell expansion in association with an increase in the Signal Transducer and Activator of Transcription 1 (STAT1) levels resulting in enhanced CD4 T cell responsiveness to IFN-α. Thus, in the setting of HIV infection, chronic stimulation of this pathway could be detrimental for CD4 T cell homeostasis. PMID:24603698

Blood CXCR3+ CD4 T Cells Are Enriched in Inducible Replication Competent HIV in Aviremic Antiretroviral Therapy-Treated Individuals

PubMed Central

Banga, Riddhima; Procopio, Francesco A.; Ruggiero, Alessandra; Noto, Alessandra; Ohmiti, Khalid; Cavassini, Matthias; Corpataux, Jean-Marc; Paxton, William A.; Pollakis, Georgios; Perreau, Matthieu

2018-01-01

We recently demonstrated that lymph nodes (LNs) PD-1+/T follicular helper (Tfh) cells from antiretroviral therapy (ART)-treated HIV-infected individuals were enriched in cells containing replication competent virus. However, the distribution of cells containing inducible replication competent virus has been only partially elucidated in blood memory CD4 T-cell populations including the Tfh cell counterpart circulating in blood (cTfh). In this context, we have investigated the distribution of (1) total HIV-infected cells and (2) cells containing replication competent and infectious virus within various blood and LN memory CD4 T-cell populations of conventional antiretroviral therapy (cART)-treated HIV-infected individuals. In the present study, we show that blood CXCR3-expressing memory CD4 T cells are enriched in cells containing inducible replication competent virus and contributed the most to the total pool of cells containing replication competent and infectious virus in blood. Interestingly, subsequent proviral sequence analysis did not indicate virus compartmentalization between blood and LN CD4 T-cell populations, suggesting dynamic interchanges between the two compartments. We then investigated whether the composition of blood HIV reservoir may reflect the polarization of LN CD4 T cells at the time of reservoir seeding and showed that LN PD-1+ CD4 T cells of viremic untreated HIV-infected individuals expressed significantly higher levels of CXCR3 as compared to CCR4 and/or CCR6, suggesting that blood CXCR3-expressing CD4 T cells may originate from LN PD-1+ CD4 T cells. Taken together, these results indicate that blood CXCR3-expressing CD4 T cells represent the major blood compartment containing inducible replication competent virus in treated aviremic HIV-infected individuals. PMID:29459864

Blood CXCR3+ CD4 T Cells Are Enriched in Inducible Replication Competent HIV in Aviremic Antiretroviral Therapy-Treated Individuals.

PubMed

Banga, Riddhima; Procopio, Francesco A; Ruggiero, Alessandra; Noto, Alessandra; Ohmiti, Khalid; Cavassini, Matthias; Corpataux, Jean-Marc; Paxton, William A; Pollakis, Georgios; Perreau, Matthieu

2018-01-01

We recently demonstrated that lymph nodes (LNs) PD-1 + /T follicular helper (Tfh) cells from antiretroviral therapy (ART)-treated HIV-infected individuals were enriched in cells containing replication competent virus. However, the distribution of cells containing inducible replication competent virus has been only partially elucidated in blood memory CD4 T-cell populations including the Tfh cell counterpart circulating in blood (cTfh). In this context, we have investigated the distribution of (1) total HIV-infected cells and (2) cells containing replication competent and infectious virus within various blood and LN memory CD4 T-cell populations of conventional antiretroviral therapy (cART)-treated HIV-infected individuals. In the present study, we show that blood CXCR3-expressing memory CD4 T cells are enriched in cells containing inducible replication competent virus and contributed the most to the total pool of cells containing replication competent and infectious virus in blood. Interestingly, subsequent proviral sequence analysis did not indicate virus compartmentalization between blood and LN CD4 T-cell populations, suggesting dynamic interchanges between the two compartments. We then investigated whether the composition of blood HIV reservoir may reflect the polarization of LN CD4 T cells at the time of reservoir seeding and showed that LN PD-1 + CD4 T cells of viremic untreated HIV-infected individuals expressed significantly higher levels of CXCR3 as compared to CCR4 and/or CCR6, suggesting that blood CXCR3-expressing CD4 T cells may originate from LN PD-1 + CD4 T cells. Taken together, these results indicate that blood CXCR3-expressing CD4 T cells represent the major blood compartment containing inducible replication competent virus in treated aviremic HIV-infected individuals.

alpha(4)beta(7) independent pathway for CD8(+) T cell-mediated intestinal immunity to rotavirus.

PubMed

Kuklin, N A; Rott, L; Darling, J; Campbell, J J; Franco, M; Feng, N; Müller, W; Wagner, N; Altman, J; Butcher, E C; Greenberg, H B

2000-12-01

Rotavirus (RV), which replicates exclusively in cells of the small intestine, is the most important cause of severe diarrhea in young children worldwide. Using a mouse model, we show that expression of the intestinal homing integrin alpha(4)ss(7) is not essential for CD8(+) T cells to migrate to the intestine or provide immunity to RV. Mice deficient in ss7 expression (ss7(-/-)) and unable to express alpha(4)ss(7) integrin were found to clear RV as quickly as wild-type (wt) animals. Depletion of CD8(+) T cells in ss7(-/-) animals prolonged viral shedding, and transfer of immune ss7(-/-) CD8(+) T cells into chronically infected Rag-2-deficient mice resolved RV infection as efficiently as wt CD8(+) T cells. Paradoxically, alpha(4)ss(7)(hi) memory CD8(+) T cells purified from wt mice that had been orally immunized cleared RV more efficiently than alpha(4)ss(7)(low) CD8(+) T cells. We explained this apparent contradiction by demonstrating that expression of alpha(4)ss(7) on effector CD8(+) T cells depends upon the site of initial antigen exposure: oral immunization generates RV-specific CD8(+) T cells primarily of an alpha(4)ss(7)(hi) phenotype, but subcutaneous immunization yields both alpha(4)ss(7)(hi) and alpha(4)ss(7)(low) immune CD8(+) T cells with anti-RV effector capabilities. Thus, alpha(4)ss(7) facilitates normal intestinal immune trafficking to the gut, but it is not required for effective CD8(+) T cell immunity.

T-cell subsets in lymph nodes identify a subgroup of follicular lymphoma patients with favorable outcome.

PubMed

Magnano, Laura; Martínez, Antonio; Carreras, Joaquim; Martínez-Trillos, Alejandra; Giné, Eva; Rovira, Jordina; Dlouhy, Ivan; Baumann, Tycho; Balagué, Olga; Campo, Elías; López-Guillermo, Armando; Villamor, Neus

2017-04-01

We have analyzed in lymph nodes at diagnosis of 75 patients with follicular lymphoma (FL) the relationship between different T-cell subpopulations, assessed by immunohistochemistry (IHC) and flow cytometry (FC), with the outcome. CD4 + cells were the most abundant T-cells in tumor tissue sections, whilst CD57 + cells were the less frequent. In addition to nonambulatory performance status, advanced stage and FLIPI, low CD4 + CD57 + /CD4 + ratio (p = .041), and low CD4 + /CD8 + ratio (p = .008) predicted poor overall survival (OS). Multivariate analysis showed that CD4 + CD57 + /CD4 + ratio was the most important variable for OS. In conclusion, T-cell subpopulations, including CD4 + CD57 + /CD4 + ratio analyzed by FC, could identify FL patients with favorable outcome.

Reactive Oxygen Species and Their Implications on CD4+ T Cells in Type 1 Diabetes.

PubMed

Previte, Dana M; Piganelli, Jon D

2017-11-28

Previous work has indicated that type 1 diabetes (T1D) pathology is highly driven by reactive oxygen species (ROS). One way in which ROS shape the autoimmune response demonstrated in T1D is by promoting CD4 + T cell activation and differentiation. As CD4 + T cells are a significant contributor to pancreatic β cell destruction in T1D, understanding how ROS impact their development, activation, and differentiation is critical. Recent Advances: CD4 + T cells themselves generate ROS via nicotinamide adenine dinucleotide phosphate (NADPH) oxidase expression and electron transport chain activity. Moreover, T cells can also be exposed to exogenous ROS generated by other immune cells (e.g., macrophages and dendritic cells) and β cells. Genetically modified animals and ROS inhibitors have demonstrated that ROS blockade during activation results in CD4 + T cell hyporesponsiveness and reduced diabetes incidence. Critical Issues and Future Directions: Although the majority of studies with regard to T1D and CD4 + T cells have been done to examine the influence of redox on CD4 + T cell activation, this is not the only circumstance in which a T cell can be impacted by redox. ROS and redox have also been shown to play roles in CD4 + T cell-related tolerogenic mechanisms, including thymic selection and regulatory T cell-mediated suppression. However, the effect of these mechanisms with respect to T1D pathogenesis remains elusive. Therefore, pursuing these avenues may provide valuable insight into the global role of ROS and redox in autoreactive CD4 + T cell formation and function. Antioxid. Redox Signal. 00, 000-000.

Enrichment of Inflammatory IL-17 and TNF-α Secreting CD4+ T Cells within Colorectal Tumors despite the Presence of Elevated CD39+ T Regulatory Cells and Increased Expression of the Immune Checkpoint Molecule, PD-1

PubMed Central

Dunne, Margaret R.; Ryan, Ciara; Nolan, Bláthnaid; Tosetto, Miriam; Geraghty, Robert; Winter, Des C.; O’Connell, P. Ronan; Hyland, John M.; Doherty, Glen A.; Sheahan, Kieran; Ryan, Elizabeth J.; Fletcher, Jean M.

2016-01-01

T cell infiltration into colorectal tumors has been shown to correlate with improved patient outcomes. However, more detailed information on the makeup and relationships between the infiltrating T cell subsets is lacking. We therefore correlated the extent of immune infiltration into colorectal tumors with the frequencies of various T cell subsets. We prospectively recruited 22 patients at the time of surgical resection for colorectal cancer. The Klintrup–Mäkinen (KM) score was used to estimate the extent of immune infiltration into colorectal tumors. The frequencies of CD4 and CD8 T cells that produced cytokines or expressed the inhibitory molecule programed cell death 1 (PD-1) were determined by flow cytometry in colorectal tumor and matched uninvolved colonic tissue. In addition, the frequency of CD4 regulatory T cell (Treg) subsets was determined. An increased frequency of CD4 T cells producing IL-17 (Th17 cells) was observed in colorectal tumor tissue compared with adjacent uninvolved tissue. These Th17 cells mostly coproduced TNF-α, but not IFN-γ. IL-17 expression correlated positively with TNF-α and IL-10. Increased expression of the immune checkpoint molecule PD-1 was found in colorectal tumors compared with adjacent uninvolved tissue. There was a negative correlation between expression of PD-1 and IFN-γ, but not IL-17, for both CD4+ and CD8+ T cells. CD4+CD25+CD127lo and CD4+CD25+CD127loFoxP3+CD39+ Treg cells were enriched in colorectal tumors. A positive correlation between KM score and percentage CD4+CD25+CD127lo Treg cells was observed in tumors, suggesting that increased immune infiltration is associated with an increased proportion of Treg cells. In addition, there was a negative correlation between the frequency of CD4+CD25+CD127lo Treg cells and the expression of IFN-γ and IL-2, but not IL-17, in tumors. Taken together, these data suggest that both PD-1 expressing T cells and Treg cells within the tumor may have a suppressive effect on T cells secreting IFN-γ, IL-2, or TNF-α, but not Th17 cells. PMID:27014625

Antibody induced CD4 down-modulation of T cells is site-specifically mediated by CD64+ cells

PubMed Central

Vogel, Stephanie; Grabski, Elena; Buschjäger, Daniela; Klawonn, Frank; Döring, Marius; Wang, Junxi; Fletcher, Erika; Bechmann, Ingo; Witte, Torsten; Durisin, Martin; Schraven, Burkhart; Mangsbo, Sara M.; Schönfeld, Kurt; Czeloth, Niklas; Kalinke, Ulrich

2015-01-01

Treatment of PBMC with the CD4-specific mAb BT-061 induces CD4 down-modulation of T cells. Here we report that addition of BT-061 to purified T cells did not confer this effect, whereas incubation of T cells in BT-061 coated wells restored CD4 down-modulation. These results implied that Fcγ receptor mediated cell-cell interactions played a role. In consistence with this hypothesis PBMC depleted of CD64+ monocytes did not confer CD4 down-modulation of BT-061 decorated T cells. Strikingly, CD4 down-modulation was observed in BT-061 treated synovial fluid punctuated from patients’ inflamed joints that comprised enhanced numbers of CD64+ cells. In contrast, in a circulating whole blood system injection of BT-061 did not induce CD4 down-modulation, due to CD64 saturation by serum IgG. Similarly, tonsil derived mononuclear cells devoid of CD64+ cells did not show CD4 down-modulation, whereas addition of blood derived monocytes restored the effect. Thus, the interaction of BT-061 decorated T cells with CD64+ cells is needed for CD4 down-modulation, implying that in patients BT-061 would primarily induce CD4 down-modulation at inflammatory sites. These results highlight the need not only to examine the interaction of a given mAb with single FcγR, but also the immunological environment that is appropriate to support such interactions. PMID:26670584

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

PubMed

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

2010-11-18

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

Intestinal double-positive CD4+CD8+ T cells of neonatal rhesus macaques are proliferating, activated memory cells and primary targets for SIVMAC251 infection

PubMed Central

Wang, Xiaolei; Das, Arpita; Lackner, Andrew A.; Veazey, Ronald S.

2008-01-01

Peripheral blood and thymic double-positive (DP) CD4+CD8+ T cells from neonates have been described earlier, but the function and immunophenotypic characteristics of other tissue-derived DP T cells are not clearly understood. Here, we demonstrate the functional and immunophenotypic characteristics of DP cells in 6 different tissues, including thymus from normal neonatal rhesus macaques (Macaca mulatta) between 0 and 21 days of age. In general, intestinal DP T cells of neonates have higher percentages of memory markers (CD28+CD95+CD45RAlowCD62Llow) and proliferation compared with single-positive (SP) CD4+ and CD8+ T cells. In addition, percentages of DP T cells increase and CD62L expression decreases as animals mature, suggesting that DP cells mature and proliferate with maturity and/or antigen exposure. Consistent with this, intestinal DP T cells in neonates express higher levels of CCR5 and are the primary targets in simian immunodeficiency virus (SIV) infection. Finally, DP T cells produce higher levels of cytokine in response to mitogen stimulation compared with SP CD4+ or CD8+ T cells. Collectively, these findings demonstrate that intestinal DP T cells of neonates are proliferating, activated memory cells and are likely involved in regulating immune responses, in contrast to immature DP T cells in the thymus. PMID:18820133

Percentage and function of CD4+CD25+ regulatory T cells in patients with hyperthyroidism

PubMed Central

Jiang, Ting-Jun; Cao, Xue-Liang; Luan, Sha; Cui, Wan-Hui; Qiu, Si-Huang; Wang, Yi-Chao; Zhao, Chang-Jiu; Fu, Peng

2018-01-01

The current study observed the percentage of peripheral blood (PB) CD4+CD25+ regulatory T cells (Tregs) and the influence of CD4+CD25+ Tregs on the proliferation of naïve CD4 T cells in patients with hyperthyroidism. Furthermore, preliminary discussions are presented on the action mechanism of CD4+CD25+ Tregs on hyperthyroidism attacks. The present study identified that compared with the percentage of PB CD4+CD25+ Tregs in healthy control subjects, no significant changes were observed in the percentage of PB CD4+CD25+ Tregs in patients with hyperthyroidism (P>0.05). For patients with hyperthyroidism, CD4+CD25+ Tregs exhibited significantly reduced inhibition of the proliferation of naïve CD4 T cells and decreased secretion capacity on the cytokines of CD4 T cells, compared with those of healthy control subjects (P<0.05). In addition, it was demonstrated that thyroid function of patients with hyperthyroidism was significantly improved (P<0.05) subsequent to receiving medication. Compared with the percentage of PB CD4+CD25+ Tregs in patients with hyperthyroidism before treatment, no significant changes were observed in the percentage of PB CD4+CD25+ Tregs in hyperthyroidism patients following treatment (P>0.05). In the patients with hyperthyroidism, following treatment, CD4+CD25+ Tregs exhibited significantly increased inhibition of the proliferation of naïve CD4 T cells and increased secretion capacity of CD4 T cell cytokines, compared with those of the patients with hyperthyroidism prior to treatment (P<0.05). PB CD4+CD25+ Tregs function was decreased in patients with hyperthyroidism, and its non-proportional decrease may be closely associated with the occurrence and progression of hyperthyroidism. PMID:29207121

Increased numbers of CD4+ and CD8+ T cells in lesional skin of cats with allergic dermatitis.

PubMed

Roosje, P J; van Kooten, P J; Thepen, T; Bihari, I C; Rutten, V P; Koeman, J P; Willemse, T

1998-07-01

The aim of this study was to characterize T cells in the skin of cats with an allergic dermatitis histologically compatible with atopic dermatitis, since T cells play an important role in the pathogenesis of atopic dermatitis in humans. We observed a significantly greater number of T cells in lesional skin of domestic short-haired cats with allergic dermatitis (n = 10; median age 5.8 years) than in the skin of healthy control animals (n = 10; median age 5.0 years). In the skin of the healthy control animals, one or two CD4+ cells and no CD8+ cells were found. A predominant increase of CD4+ T cells and a CD4+/CD8+ ratio (mean +/- SD: 3.9 +/- 2.0) was found in the lesional skin of 10 cats with allergic dermatitis. The CD4+/CD8+ cell ratio in the skin of healthy control animals could not be determined because of the absence of CD8+ cells. The CD4+/CD8+ cell ratio in the peripheral blood of 10 cats with allergic dermatitis (mean +/- SD: 1.9 +/- 0.4) did not differ significantly from that in 10 healthy control animals (2.2 +/- 0.4). The CD4+/CD8+ cell ratio and predominance of CD4+ T cells in the lesional skin of cats with allergic dermatitis is comparable to that found in atopic dermatitis in humans. In addition, the observed increase of CD4+ T cells in the nonlesional skin of cats with allergic dermatitis compared to the skin of healthy cats is similar to what is seen in humans. Cytokines produced by T cells and antigen-specific T cells are important mediators in the inflammatory cascade resulting in atopic dermatitis in humans. This study is a first step to investigate their role in feline allergic dermatitis.

Differential requirements of CD4(+) T-cell signals for effector cytotoxic T-lymphocyte (CTL) priming and functional memory CTL development at higher CD8(+) T-cell precursor frequency.

PubMed

Umeshappa, Channakeshava S; Nanjundappa, Roopa H; Xie, Yufeng; Freywald, Andrew; Xu, Qingyong; Xiang, Jim

2013-04-01

Increased CD8(+) T-cell precursor frequency (PF) precludes the requirement of CD4(+) helper T (Th) cells for primary CD8(+) cytotoxic T-lymphocyte (CTL) responses. However, the key questions of whether unhelped CTLs generated at higher PF are functional effectors, and whether unhelped CTLs can differentiate into functional memory cells at higher PF are unclear. In this study, ovalbumin (OVA) -pulsed dendritic cells (DC(OVA)) derived from C57BL/6, CD40 knockout (CD40(-/-)) or CD40 ligand knockout (CD40L(-/-)) mice were used to immunize C57BL/6, Ia(b-/-), CD40(-/-) or CD40L(-/-) mice, whose PF was previously increased with transfer of 1 × 10(6) CD8(+) T cells derived from OVA-specific T-cell receptor (TCR) transgenic OTI, OTI(CD40(-/-)) or OTI(CD40L(-/-)) mice. All the immunized mice were then assessed for effector and memory CTL responses. Following DC immunization, relatively comparable CTL priming occurred without CD4(+) T-cell help and Th-provided CD40/CD40L signalling. In addition, the unhelped CTLs were functional effectors capable of inducing therapeutic immunity against established OVA-expressing tumours. In contrast, the functional memory development of CTLs was severely impaired in the absence of CD4(+) T-cell help and CD40/CD40L signalling. Finally, unhelped memory CTLs failed to protect mice against lethal tumour challenge. Taken together, these results demonstrate that CD4(+) T-cell help at higher PF, is not required for effector CTL priming, but is required for functional memory CTL development against cancer. Our data may impact the development of novel preventive and therapeutic approaches in cancer patients with compromised CD4(+) T-cell functions. © 2012 Blackwell Publishing Ltd.

CD4 T Cell Epitope Specificity and Cytokine Potential Are Preserved as Cells Transition from the Lung Vasculature to Lung Tissue following Influenza Virus Infection.

PubMed

DiPiazza, Anthony; Laniewski, Nathan; Rattan, Ajitanuj; Topham, David J; Miller, Jim; Sant, Andrea J

2018-07-01

Pulmonary CD4 T cells are critical in respiratory virus control, both by delivering direct effector function and through coordinating responses of other immune cells. Recent studies have shown that following influenza virus infection, virus-specific CD4 T cells are partitioned between pulmonary vasculature and lung tissue. However, very little is known about the peptide specificity or functional differences of CD4 T cells within these two compartments. Using a mouse model of influenza virus infection in conjunction with intravascular labeling in vivo , the cell surface phenotype, epitope specificity, and functional potential of the endogenous polyclonal CD4 T cell response was examined by tracking nine independent CD4 T cell epitope specificities. These studies revealed that tissue-localized CD4 cells were globally distinct from vascular cells in expression of markers associated with transendothelial migration, residency, and micropositioning. Despite these differences, there was little evidence for remodeling of the viral epitope specificity or cytokine potential as cells transition from vasculature to the highly inflamed lung tissue. Our studies also distinguished cells in the pulmonary vasculature from peripheral circulating CD4 T cells, providing support for the concept that the pulmonary vasculature does not simply reflect circulating cells that are trapped within the narrow confines of capillary vessels but rather is enriched in transitional cells primed in the draining lymph node that have specialized potential to enter the lung tissue. IMPORTANCE CD4 T cells convey a multitude of functions in immunity to influenza, including those delivered in the lymph node and others conveyed by CD4 T cells that leave the lymph node, enter the blood, and extravasate into the lung tissue. Here, we show that the transition of recently primed CD4 cells detected in the lung vasculature undergo profound changes in expression of markers associated with tissue localization as they establish residence in the lung. However, this transition does not edit CD4 T cell epitope specificity or the cytokine potential of the CD4 T cells. Thus, CD4 T cells that enter the infected lung can convey diverse functions and have a sufficiently broad viral antigen specificity to detect the complex array of infected cells within the infected tissue, offering the potential for more effective protective function. Copyright © 2018 American Society for Microbiology.

Co-administration of plasmid-encoded granulocyte-macrophage colony-stimulating factor increases human immunodeficiency virus-1 DNA vaccine-induced polyfunctional CD4+ T-cell responses

PubMed Central

Santana, Vinicius Canato; Almeida, Rafael Ribeiro; Ribeiro, Susan Pereira; Ferreira, Luís Carlos de Souza; Kalil, Jorge; Rosa, Daniela Santoro; Cunha-Neto, Edecio

2015-01-01

T-cell based vaccines against human immunodeficiency virus (HIV) generate specific responses that may limit both transmission and disease progression by controlling viral load. Broad, polyfunctional, and cytotoxic CD4+T-cell responses have been associated with control of simian immunodeficiency virus/HIV-1 replication, supporting the inclusion of CD4+ T-cell epitopes in vaccine formulations. Plasmid-encoded granulocyte-macrophage colony-stimulating factor (pGM-CSF) co-administration has been shown to induce potent CD4+ T-cell responses and to promote accelerated priming and increased migration of antigen-specific CD4+ T-cells. However, no study has shown whether co-immunisation with pGM-CSF enhances the number of vaccine-induced polyfunctional CD4+ T-cells. Our group has previously developed a DNA vaccine encoding conserved, multiple human leukocyte antigen (HLA)-DR binding HIV-1 subtype B peptides, which elicited broad, polyfunctional and long-lived CD4+ T-cell responses. Here, we show that pGM-CSF co-immunisation improved both magnitude and quality of vaccine-induced T-cell responses, particularly by increasing proliferating CD4+ T-cells that produce simultaneously interferon-γ, tumour necrosis factor-α and interleukin-2. Thus, we believe that the use of pGM-CSF may be helpful for vaccine strategies focused on the activation of anti-HIV CD4+ T-cell immunity. PMID:26602876

Nutritional and immunological correlates of memory and neurocognitive development among HIV infected children living in Kayunga, Uganda

PubMed Central

Horacio, Ruiseñor-Escudero; Itziar, Familiar-Lopez; Alla, Sikorskii; Nikita, Jambulingam; Noelline, Nakasujja; Robert, Opoka; Judith, Bass; Michael, Boivin

2015-01-01

Objective To identify the nutritional and immunological correlates of memory and neurocognitive development as measured by the Mullen Scales of Early Learning (MSEL) and by the Color Object Association Test (COAT) among children in Uganda. Design This analysis uses baseline data collected between 2008 and 2010 from 119 HIV-infected children ages 1–6 years participating in a randomized controlled trial of an interventional parenting program in Kayunga, Uganda. Methods Peripheral blood draws were performed to determine immunological biomarkers. Unadjusted and adjusted linear regression models were used to relate MSEL and COAT scores to sociodemographic characteristics, weight-for-age Z-scores (WAZ), antiretroviral therapy (ART) status and immunological biomarkers. Results 111 children were included in the final analysis. Lower levels of CD4+ CD38+ T-cells (p=0.04) were associated to higher Immediate and Total Recall scores (p=0.04). Higher levels of CD8+ HLA-DR+ T-cells were associated with higher Total Recall score (p=0.04) of the COAT. Higher CD4+ CD38+ HLA-DR+ T-cells levels were associated with higher Gross Motor scores of the MSEL (p=0.02). WAZ was positively correlated to Visual Reception, Fine Motor, Expressive Language and composite score of the MSEL. Conclusions Overall, WAZ was a stronger predictor of neurocognitive outcomes assessed by the MSEL. CD4+ CD38+ T-cells were more specifically associated with memory-related outcomes. Future research should include immunological markers and standardized neurocognitive tests to further understand this relationship. PMID:26605506

Protection by universal influenza vaccine is mediated by memory CD4 T cells.

PubMed

Valkenburg, Sophie A; Li, Olive T W; Li, Athena; Bull, Maireid; Waldmann, Thomas A; Perera, Liyanage P; Peiris, Malik; Poon, Leo L M

2018-07-05

There is a diverse array of influenza viruses which circulate between different species, reassort and drift over time. Current seasonal influenza vaccines are ineffective in controlling these viruses. We have developed a novel universal vaccine which elicits robust T cell responses and protection against diverse influenza viruses in mouse and human models. Vaccine mediated protection was dependent on influenza-specific CD4 + T cells, whereby depletion of CD4 + T cells at either vaccination or challenge time points significantly reduced survival in mice. Vaccine memory CD4 + T cells were needed for early antibody production and CD8 + T cell recall responses. Furthermore, influenza-specific CD4 + T cells from vaccination manifested primarily Tfh and Th1 profiles with anti-viral cytokine production. The vaccine boosted H5-specific T cells from human PBMCs, specifically CD4 + and CD8 + T effector memory type, ensuring the vaccine was truly universal for its future application. These findings have implications for the development and optimization of T cell activating vaccines for universal immunity against influenza. Copyright © 2018 Elsevier Ltd. All rights reserved.

Circulating CD4+CXCR5+ T cells contribute to proinflammatory responses in multiple ways in coronary artery disease.

PubMed

Ding, Ru; Gao, Wenwu; He, Zhiqing; Wu, Feng; Chu, Yang; Wu, Jie; Ma, Lan; Liang, Chun

2017-11-01

Coronary artery disease (CAD) is a common subtype of cardiovascular disease. The major contributing event is atherosclerosis, which is a progressive inflammatory condition resulting in the thickening of the arterial wall and the formation of atheromatous plaques. Recent evidence suggests that circulating CD4 + CXCR5 + T cells can contribute to inflammatory reactions. In this study, the frequency, phenotype, and function of circulating CD4 + CXCR5 + T cells in CAD patients were examined. Data showed that circulating CD4 + CXCR5 + T cells in CAD patients were enriched with a PD-1 + CCR7 - subset, which was previously identified as the most potent in B cell help. The CD4 + CXCR5 + T cells in CAD patients also secreted significantly higher levels of IFN-γ, IL-17A, and IL-21 than those from healthy controls. Depleting the PD-1 + population significantly reduced the cytokine secretion. Interestingly, the CD4 + CXCR5 + PD-1 - T cells significantly upregulated PD-1 following anti-CD3/CD28 or SEB stimulation. CD4 + CXCR5 + T cells from CAD patients also demonstrated more potent capacity to stimulate B cell inflammation than those from healthy individuals. The phosphorylation of STAT1 and STAT3 were significantly higher in B cells incubated with CD4 + CXCR5 + T cells from CAD than controls. The IL-6 and IFN-γ expression were also significantly higher in B cells incubated with CD4 + CXCR5 + T cells from CAD. Together, this study demonstrated that CAD patients presented a highly activated CD4 + CXCR5 + T cell subset that could contribute to proinflammatory responses in multiple ways. The possibility of using CD4 + CXCR5 + T cells as a therapeutic target should therefore be examined in CAD patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Reconstitution of Intestinal CD4 and Th17 T Cells in Antiretroviral Therapy Suppressed HIV-Infected Subjects: Implication for Residual Immune Activation from the Results of a Clinical Trial

PubMed Central

d'Ettorre, Gabriella; Baroncelli, Silvia; Micci, Luca; Ceccarelli, Giancarlo; Andreotti, Mauro; Sharma, Prachi; Fanello, Gianfranco; Fiocca, Fausto; Cavallari, Eugenio Nelson; Giustini, Noemi; Mallano, Alessandra; Galluzzo, Clementina M.; Vella, Stefano; Mastroianni, Claudio M.; Silvestri, Guido; Paiardini, Mirko; Vullo, Vincenzo

2014-01-01

Introduction During HIV infection the severe depletion of intestinal CD4+ T-cells is associated with microbial translocation, systemic immune activation, and disease progression. This study examined intestinal and peripheral CD4+ T-cell subsets reconstitution under combined antiretroviral therapy (cART), and systemic immune activation markers. Methods This longitudinal single-arm pilot study evaluates CD4+ T cells, including Th1 and Th17, in gut and blood and soluble markers for inflammation in HIV-infected individuals before (M0) and after eight (M8) months of cART. From January 2010 to December 2011, 10 HIV-1 naïve patients were screened and 9 enrolled. Blood and gut CD4+ T-cells subsets and cellular immune activation were determined by flow-cytometry and plasma soluble CD14 by ELISA. CD4+ Th17 cells were detected in gut biopsies by immunohistochemistry. Microbial translocation was measured by limulus-amebocyte-lysate assay to detect bacterial lipopolysaccharide (LPS) and PCR Real Time to detect plasma bacterial 16S rDNA. Results Eight months of cART increased intestinal CD4+ and Th17 cells and reduced levels of T-cell activation and proliferation. The magnitude of intestinal CD4+ T-cell reconstitution correlated with the reduction of plasma LPS. Importantly, the magnitude of Th17 cells reconstitution correlated directly with blood CD4+ T-cell recovery. Conclusion Short-term antiretroviral therapy resulted in a significant increase in the levels of total and Th17 CD4+ T-cells in the gut mucosa and in decline of T-cell activation. The observation that pre-treatment levels of CD4+ and of CD8+ T-cell activation are predictors of the magnitude of Th17 cell reconstitution following cART provides further rationale for an early initiation of cART in HIV-infected individuals. Trial Registration ClinicalTrials.gov NCT02097381 PMID:25340778

Down-regulation of microRNA-451a facilitates the activation and proliferation of CD4+ T cells by targeting Myc in patients with dilated cardiomyopathy.

PubMed

Zeng, Zhipeng; Wang, Ke; Li, Yuanyuan; Xia, Ni; Nie, Shaofang; Lv, Bingjie; Zhang, Min; Tu, Xin; Li, Qianqian; Tang, Tingting; Cheng, Xiang

2017-04-07

CD4 + T cells are abnormally activated in patients with dilated cardiomyopathy (DCM) and might be associated with the immunopathogenesis of the disease. However, the underlying mechanisms of CD4 + T cell activation remain largely undefined. Our aim was to investigate whether the dysregulation of microRNAs (miRNAs) was associated with CD4 + T cell activation in DCM. CD4 + T cells from DCM patients showed increased expression levels of CD25 and CD69 and enhanced proliferation in response to anti-CD3/28, indicating an activated state. miRNA profiling analysis of magnetically sorted CD4 + T cells revealed a distinct pattern of miRNA expression in CD4 + T cells from DCM patients compared with controls. The level of miRNA-451a (miR-451a) was significantly decreased in the CD4 + T cells of DCM patients compared with that of the controls. The transfection of T cells with an miR-451a mimic inhibited their activation and proliferation, whereas an miR-451a inhibitor produced the opposite effects. Myc was directly inhibited by miR-451a via interaction with its 3'-UTR, thus identifying it as an miR-451a target in T cells. The knockdown of Myc suppressed the activation and proliferation of T cells, and the expression of Myc was significantly up-regulated at the mRNA level in CD4 + T cells from patients with DCM. A strong inverse correlation was observed between the Myc mRNA expression and miR-451a transcription level. Our data suggest that the down-regulation of miR-451a contributes to the activation and proliferation of CD4 + T cells by targeting the transcription factor Myc in DCM patients and may contribute to the immunopathogenesis of DCM. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

High frequencies of Th1-type CD4(+) T cells specific to HTLV-1 Env and Tax proteins in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis.

PubMed

Goon, Peter K C; Hanon, Emmanuel; Igakura, Tadahiko; Tanaka, Yuetsu; Weber, Jonathan N; Taylor, Graham P; Bangham, Charles R M

2002-05-01

CD4(+) T cells are critical for inducing and maintaining efficient humoral and cellular immune responses to pathogens. The CD4(+) T-cell response in human T-lymphotropic virus 1 (HTLV-1) infection has not been studied in detail. However, CD4(+) T cells have been shown to predominate in early lesions in HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). We present direct estimates of HTLV-1 Env- and Tax-specific CD4(+) T-cell frequencies in patients infected with HTLV-1. We first showed that there was a strong bias toward the Th1 phenotype in these HTLV-1-specific CD4(+) T cells in patients with HAM/TSP. We then demonstrated significantly higher frequencies of HTLV-1-specific Th1-type CD4(+) T cells in HAM/TSP patients than in asymptomatic HTLV-1 carriers. The majority of these HTLV-1-specific CD4(+) T cells did not express HTLV-1 Tax and were therefore unlikely to be infected by HTLV-1. High frequencies of activated HTLV-1-specific CD4(+) T cells of the Th1 phenotype might contribute to the initiation or pathogenesis of HAM/TSP and other HTLV-1-associated inflammatory diseases.

CD20+ T cell numbers are decreased in untreated HIV-1 patients and recover after HAART.

PubMed

Förster, Friederike; Singla, Anuj; Arora, Sunil K; Schmidt, Reinhold E; Jacobs, Roland

2012-08-30

To elucidate if CD20(+) T cells are affected by HIV-1 infection and may have a prognostic value for the course of disease, numbers of CD20(+) T cells were determined in healthy controls, untreated and HAART-treated HIV-1 patients. Coexpression patterns of CD4, CD8, and CD38 were analysed on CD3(+)CD20(+) and CD3(+)CD20(-) T cells. We found a significant decrease of CD20(+) T cell numbers in untreated HIV-1 patients (1.4%) as compared to healthy controls (2.5%) which recovered under HAART (1.9%). Particularly, the CD8(+) T cell compartment was affected revealing significant differences between healthy controls (3.4%) and both treated (1.7%) and untreated (1.1%) patients. CD38 was expressed on a few CD20(+) T cells but preferentially on CD20(-) cells in all three groups. IFN-γ production was measured upon cell activation using PMA alone or in combination with ionomycin in order to assess functional capacities of the cells. PMA alone was much more effective in CD20(+) cells regardless of CD38 coexpression, indicating a supportive role of CD20 but not CD38 in T cell activation. Here we present data showing that CD3(+)CD20(+) T cells are decreased in untreated HIV-1 patients and normal numbers are restored under HAART. Expression of CD20 and CD38 is independently regulated on T cells. Contrary to CD38, CD20 can substitute ionophores for Ca(2+) flux in early T cell activation and also strongly amplify cell stimulation in the presence of Ca(2+) ionophores, indicating that CD20 contributes to T cell activation. Copyright © 2012 Elsevier B.V. All rights reserved.

Antitumour activity mediated by CD4+ cytotoxic T lymphocytes against MHC class II-negative mouse hepatocellular carcinoma induced by dendritic cell vaccine and interleukin-12.

PubMed

Homma, Sadamu; Komita, Hideo; Sagawa, Yukiko; Ohno, Tsuneya; Toda, Gotaro

2005-08-01

When BALA/c mice with BNL hepatocellular carcinoma (HCC) were treated with dendritic cells fused with BNL cells (DC/BNL) and recombinant murine interleukin (IL)-12, tumour development was significantly suppressed, whereas treatment with either DC/BNL or IL-12 alone did not show a tumour-suppressive effect. Antitumour activity induced by DC/BNL + IL-12 was abrogated by depletion of CD4+ T cells, but not by depletion of CD8+ T cells or natural killer cells. Splenic CD4+ T cells and CD8+ T cells from DC/BNL-treated mice showed cytotoxic activity against BNL cells after 3 days of incubation with DC/BNL, although BNL cells do not express major histocompatibility complex (MHC) class II molecules even after treatment with interferon (INF)-gamma. Furthermore, CD4+ T cells killed syngeneic-irrelevant CT26 cells and even allogeneic Hepa1-6 cells. This cytotoxicity was blocked by concanamycin A, but not by an anti-Fas ligand (FasL) monoclonal antibody, indicating that cytotoxic activity was mediated by perforin. Immunofluorescence microscopy demonstrated that abundant CD4+ T cells and MHC class II-positive macrophages, but not CD8(+) T cells, had infiltrated tumour tissue in mice treated with DC/BNL + IL-12. Flow cytometric analysis of tumour-infiltrating cells in mice treated with DC/BNL + IL-12 showed increases in CD4+ T cells and MHC class II+ CD11b+ cells but not in CD8+ T cells or MHC class I+ CD11b+ cells. Our results suggest that, in BNL-bearing mice treated with DC/BNL + IL-12, tumour macrophages activated by INF-gamma produced by IL-12-stimulated T cells might present BNL tumour antigens and activate DC/BNL-primed CD4+ cytotoxic T lymphocytes (CTLs) in a MHC class II-dependent manner, leading to perforin-mediated bystander killing of neighbouring MHC class II-negative tumour cells.

Antitumour activity mediated by CD4+ cytotoxic T lymphocytes against MHC class II-negative mouse hepatocellular carcinoma induced by dendritic cell vaccine and interleukin-12

PubMed Central

Homma, Sadamu; Komita, Hideo; Sagawa, Yukiko; Ohno, Tsuneya; Toda, Gotaro

2005-01-01

When BALA/c mice with BNL hepatocellular carcinoma (HCC) were treated with dendritic cells fused with BNL cells (DC/BNL) and recombinant murine interleukin (IL)-12, tumour development was significantly suppressed, whereas treatment with either DC/BNL or IL-12 alone did not show a tumour-suppressive effect. Antitumour activity induced by DC/BNL + IL-12 was abrogated by depletion of CD4+ T cells, but not by depletion of CD8+ T cells or natural killer cells. Splenic CD4+ T cells and CD8+ T cells from DC/BNL-treated mice showed cytotoxic activity against BNL cells after 3 days of incubation with DC/BNL, although BNL cells do not express major histocompatibility complex (MHC) class II molecules even after treatment with interferon (INF)-γ. Furthermore, CD4+ T cells killed syngeneic-irrelevant CT26 cells and even allogeneic Hepa1-6 cells. This cytotoxicity was blocked by concanamycin A, but not by an anti-Fas ligand (FasL) monoclonal antibody, indicating that cytotoxic activity was mediated by perforin. Immunofluorescence microscopy demonstrated that abundant CD4+ T cells and MHC class II-positive macrophages, but not CD8+ T cells, had infiltrated tumour tissue in mice treated with DC/BNL + IL-12. Flow cytometric analysis of tumour-infiltrating cells in mice treated with DC/BNL + IL-12 showed increases in CD4+ T cells and MHC class II+ CD11b+ cells but not in CD8+ T cells or MHC class I+ CD11b+ cells. Our results suggest that, in BNL-bearing mice treated with DC/BNL + IL-12, tumour macrophages activated by INF-γ produced by IL-12-stimulated T cells might present BNL tumour antigens and activate DC/BNL-primed CD4+ cytotoxic T lymphocytes (CTLs) in a MHC class II-dependent manner, leading to perforin-mediated bystander killing of neighbouring MHC class II-negative tumour cells. PMID:16011514

Epstein-Barr virus effect on frequency of functionally distinct T cell subsets in children with infectious mononucleosis.

PubMed

Sulik, Artur; Oldak, Elzbieta; Kroten, Anna; Lipska, Alina; Radziwon, Piotr

2014-09-01

Epstein-Barr virus is a common human pathogen which infects the great majority of population worldwide. A striking proliferation of CD8⁺ T cells is an immune response to EBV invasion of B lymphocytes during infectious mononucleosis. The aim of the study was to analyze frequencies of CD28⁺CD95⁻, CD28⁺CD95⁺, CD28⁻CD95⁺ T cell subsets putative naïve (T(N)), central (T(CM)) and effector memory (T(EM)) T cells in children with infectious mononucleosis. Multiparameter flow cytometric analysis of CD4⁺ and CD8⁺ T cell subsets was performed in 19 children with acute infectious mononucleosis. The CD4⁺/CD8⁺ ratio was found to be decreased (0.53) in children with infectious mononucleosis. Median T(N), T(CM), T(EM) frequencies were estimated to be 3.7, 4.5, 15.1% of CD8⁺ and 23, 59.3, 5.5% of CD4⁺ T cells, respectively. In the present study we demonstrated negative correlations between CD8⁺CD28⁺CD95⁺ and CD8⁺CD28⁻CD95⁺ T cells and both VCA IgM antibody titers and disease duration. However, no such correlation was found when subset of CD4⁺ T cells or CD8⁺CD28⁺CD95⁻ cells was compared. We conclude that there is a rapid decrease in the number of memory CD8⁺ T cells in early acute stage of infectious mononucleosis. Copyright © 2014 Medical University of Bialystok. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Providence of CD25+ KIR+ CD127- FOXP3- CD8+ T cell subset determines the dynamics of tumor immune surveillance.

PubMed

Chakraborty, Sreeparna; Bhattacharjee, Pushpak; Panda, Abir K; Kajal, Kirti; Bose, Sayantan; Sa, Gaurisankar

2018-05-16

CD8 + T-regulatory cells are progressively emerging as crucial components of immune system. The previous report suggests the presence of FOXP3-positive CD8 + Treg cells, similar to CD4 + Tregs, in cancer patients which produce high levels of IL10 and TGFβ for its immunosuppressive activities. At an early stage of tumor development, we have identified a subset of FOXP3-negative CD8 + CD25 + KIR + CD127 - a Treg-like subset which is essentially IFNγ-positive. However, this early induced CD8 + CD25 + CD127 - T cell subset certainly distinct from the IFNγ + CD8 + T-effecter cells. This CD8 + CD25 + CD127 - T cells are equipped with other FOXP3 - CD8 + Treg cell signature markers and can selectively suppress HLA-E-positive T FH cells in autoimmune condition as well as tumor-induced CD4 + Treg cells. Contrasting to FOXP3-positive CD8 + Tregs, this subset does not inhibit effector T cell proliferation or their functions as they are HLA-E-negative. Adoptive transfer of this early-CD8 + Treg-like subset detained tumor growth and inhibited CD4 + Treg generation that obstacles the immune surveillance and impairs cancer immunotherapy. At the late stage of tumor development, when CD4 + Treg cells dominate tumor-microenvironment, CD4 + Tregs mediate the clonal deletion of this tumor-suppressive FOXP3 - IFNγ + CD8 + CD25 + CD127 - T cells and ensures tumor immune evasion. Our findings suggest that at an early stage of the tumor, this tumor-induced IFNγ-producing FOXP3-negative CD8 + CD25 + CD127 - T cell subset can potentiate immune surveillance by targeting HLA-E-restricted CD4 + Treg cells whereas leaving the effector T cell population unaffected, and hence maneuvering their profile can open up a new avenue in cancer immunotherapy. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Histone demethylase JMJD3 regulates CD11a expression through changes in histone H3K27 tri-methylation levels in CD4+ T cells of patients with systemic lupus erythematosus.

PubMed

Yin, Heng; Wu, Haijing; Zhao, Ming; Zhang, Qing; Long, Hai; Fu, Siqi; Lu, Qianjin

2017-07-25

Aberrant CD11a overexpression in CD4+ T cells induces T cell auto-reactivity, which is an important factor for systemic lupus erythematosus (SLE) pathogenesis. Although many studies have focused on CD11a epigenetic regulation, little is known about histone methylation. JMJD3, as a histone demethylase, is capable of specifically removing the trimethyl group from the H3K27 lysine residue, triggering target gene activation. Here, we examined the expression and function of JMJD3 in CD4+ T cells from SLE patients. Significantly decreased H3K27me3 levels and increased JMJD3 binding were detected within the ITGAL (CD11a) promoter locus in SLE CD4+ T cells compared with those in healthy CD4+ T cells. Moreover, overexpressing JMJD3 through the transfection of pcDNA3.1-JMJD3 into healthy donor CD4+ T cells increased JMJD3 enrichment and decreased H3K27me3 enrichment within the ITGAL (CD11a) promoter and up-regulated CD11a expression, leading to T and B cell hyperactivity. Inhibition of JMJD3 via JMJD3-siRNA in SLE CD4+ T cells showed the opposite effects. These results demonstrated that histone demethylase JMJD3 regulates CD11a expression in lupus T cells by affecting the H3K27me3 levels in the ITGAL (CD11a) promoter region, and JMJD3 might thereby serve as a potential therapeutic target for SLE.

MicroRNA-126 deficiency enhanced the activation and function of CD4+ T cells by elevating IRS-1 pathway.

PubMed

Chu, F; Hu, Y; Zhou, Y; Guo, M; Lu, J; Zheng, W; Xu, H; Zhao, J; Xu, L

2018-02-01

Recent evidence has shown that microRNA-126 (miR-126) has been involved in the development and function of immune cells, which contributed to the pathogenesis of related clinical diseases. However, the potential role of miR-126 in the development and function of CD4 + T cells remains largely unknown. Here we first found that the activation and proliferation, as well as the expression of interferon (IFN)-γ, of CD4 + T cells from miR-126 knock-down (KD) mice using the miRNA-sponge technique were enhanced significantly in vitro, compared with those in CD4 + T cells from wild-type (WT) mice. To monitor further the possible effect of miR-126 deficiency on the function of CD4 + T cells in vivo, we used dextran sulphate sodium (DSS)-induced murine model of acute autoimmune colitis and found that miR-126 deficiency could elevate the pathology of colitis. Importantly, the proportion of CD4 + T cells in splenocytes increased significantly in miR-126KD mice. Moreover, the expression levels of CD69 and CD44 on CD4 + T cells increased significantly and the expression level of CD62L decreased significantly. Of note, adoptive cell transfer assay showed that the pathology of colitis was more serious in carboxyfluorescein succinimidyl ester (CFSE)-labelled miR-126KD CD4 + T cell-transferred group, compared with that in the CFSE-labelled WT CD4 + T cells transferred group. Consistently, the expression levels of CD69 and CD44 on CFSE + cells increased significantly. Furthermore, both the proliferation and IFN-γ secretion of CFSE + cells also increased significantly in the CFSE-labelled miR-126KD CD4 + T cell-transferred group. Mechanistic evidence showed that the expression of insulin receptor substrate 1 (IRS-1), as a functional target of miR-126, was elevated in CD4 + T cells from miR-126KD mice, accompanied by altered transduction of the extracellular regulated kinase, protein B (AKT) and nuclear factor kappa B (NF-κB) pathway. Our data revealed a novel role in which miR-126 was an intrinsic regulator in the function of CD4 + T cells, which provided preliminary basis for exploring further the role of miR-126 in the development, function of CD4 + T cells and related clinical diseases. © 2017 British Society for Immunology.

ICOS and Bcl6-dependent pathways maintain a CD4 T cell population with memory-like properties during tuberculosis

PubMed Central

Moguche, Albanus O.; Shafiani, Shahin; Clemons, Corey; Larson, Ryan P.; Dinh, Crystal; Higdon, Lauren E.; Cambier, C.J.; Sissons, James R.; Gallegos, Alena M.; Fink, Pamela J.

2015-01-01

Immune control of persistent infection with Mycobacterium tuberculosis (Mtb) requires a sustained pathogen-specific CD4 T cell response; however, the molecular pathways governing the generation and maintenance of Mtb protective CD4 T cells are poorly understood. Using MHCII tetramers, we show that Mtb-specific CD4 T cells are subject to ongoing antigenic stimulation. Despite this chronic stimulation, a subset of PD-1+ cells is maintained within the lung parenchyma during tuberculosis (TB). When transferred into uninfected animals, these cells persist, mount a robust recall response, and provide superior protection to Mtb rechallenge when compared to terminally differentiated Th1 cells that reside preferentially in the lung-associated vasculature. The PD-1+ cells share features with memory CD4 T cells in that their generation and maintenance requires intrinsic Bcl6 and intrinsic ICOS expression. Thus, the molecular pathways required to maintain Mtb-specific CD4 T cells during ongoing infection are similar to those that maintain memory CD4 T cells in scenarios of antigen deprivation. These results suggest that vaccination strategies targeting the ICOS and Bcl6 pathways in CD4 T cells may provide new avenues to prevent TB. PMID:25918344

Opioid maintenance therapy restores CD4+ T cell function by normalizing CD4+CD25(high) regulatory T cell frequencies in heroin user.

PubMed

Riss, Gina-Lucia; Chang, Dae-In; Wevers, Carolin; Westendorf, Astrid M; Buer, Jan; Scherbaum, Norbert; Hansen, Wiebke

2012-08-01

There is an increasing body of evidence that heroin addiction is associated with severe alterations in immune function, which might contribute to an increased risk to contract infectious diseases like hepatitis B and C or HIV. However, the impact of heroin consumption on the CD4(+) T cell compartment is not well understood. Therefore, we analyzed the frequency and functional phenotype of CD4(+) T cells as well as immune-suppressive CD4(+)CD25(high) regulatory T cells (Tregs) isolated from the peripheral blood of opiate addicts currently abusing heroin (n=27) in comparison to healthy controls (n=25) and opiate addicts currently in opioid maintenance treatment (OMT; n=27). Interestingly, we detected a significant increase in the percentage of CD4(+)CD25(high) Tregs in the peripheral blood of heroin addicted patients in contrast to patients in OMT. The proliferative response of CD4(+) T cells upon stimulation with anti-CD3 and anti-CD28 antibodies was significantly decreased in heroin users, but could be restored by depletion of CD25(high) regulatory T cells from CD4(+) T cells to similar values as observed from healthy controls and patients in OMT. These results suggest that impaired immune responses observed in heroin users are related to the expansion of CD4(+)CD25(high) Tregs and more importantly, can be restored by OMT. Copyright © 2012 Elsevier Inc. All rights reserved.

[T-lymphocytes--do they control rheumatic immune responses?].

PubMed

Wagner, U; Schulze-Koops, H

2005-09-01

T cells, in particular CD4(+) T cells, have been implicated in mediating many aspects of rheumatoid inflammation. In rheumatoid arthritis (RA), CD4(+) T cells display various functional abnormalities in the synovium as well as in the peripheral circulation. Current evidence suggests, however, that the role of CD4(+) T cells in the development of rheumatoid inflammation exceeds that of activated pro-inflammatory effector T cells that drive the chronic autoimmune response. Subsets of CD4(+) T cells with regulatory capacity, such as CD25(+) Tregs, have been identified in mice and man, and recent observations suggest that in RA, the function of these regulatory T cells is severely impaired. Thus, in RA, defective regulatory immune mechanisms might allow the breakdown of peripheral tolerance, following which the detrimental CD4(+) T-cell-driven immune response evolves and proceeds to chronic inflammation. Here, we review the functional abnormalities and the contribution of different T-cell subsets to rheumatoid inflammation.

Functional characterization of BK virus-specific CD4+ T cells with cytotoxic potential in seropositive adults.

PubMed

Zhou, Wendi; Sharma, Madeva; Martinez, Joy; Srivastava, Tumul; Diamond, Don J; Knowles, Wendy; Lacey, Simon F

2007-09-01

BK polyomavirus (BKV) reactivation is associated with a failure of T cell immunity in kidney transplant patients, and may lead to BKV-associated nephropathy (BKVN) and loss of the allograft. BKV reactivation in hematopoietic stem cell transplant recipients is associated with hemorrhagic cystitis. We have investigated T cell responses to overlapping peptide mixtures corresponding to the whole BKV major T antigen (TAg) and major capsid protein (VP1) in peripheral blood mononuclear cell samples from a cohort of healthy BKV-seropositive subjects. The majority of these individuals possessed populations of both CD8(+) and CD4(+) T cells specific for these BKV antigens. After expansion in culture, the majority of the BKV-specific CD4(+) T cells, in addition to expressing CD40L (CD154), secreted both interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha, contained both granzyme A and granzyme B, and degranulated/mobilized CD107 in response to antigen-specific stimulation. These T cells thus represent potentially functional BKV-specific cytotoxic CD4(+) T lymphocytes. Secretion of both TNF-alpha and IFN-gamma by CD154(+)CD4(+) T cells on BKV-specific stimulation was associated with higher levels of granzyme B and a higher proportion of degranulating cells compared with CD154(+)CD4(+) T cells producing only IFN-gamma or neither cytokine. These healthy subjects also harbored populations of functional CD8(+) T cells specific for one or more of three newly defined HLA-A 02-restricted cytotoxic T lymphocyte epitopes within the BKV TAg as well as two HLA-A 02-restricted epitopes within the BKV VP1 we have previously described. The BKV-specific CD4(+) T cells characterized in this study may play a part in maintaining persistent memory T cell responses to the virus and thus contribute to the immune control of BKV in healthy individuals.

Phenotypic and functional characteristics of CD4+ CD39+ FOXP3+ and CD4+ CD39+ FOXP3neg T-cell subsets in cancer patients.

PubMed

Schuler, Patrick J; Schilling, Bastian; Harasymczuk, Malgorzata; Hoffmann, Thomas K; Johnson, Jonas; Lang, Stephan; Whiteside, Theresa L

2012-07-01

Human CD4(+) CD39(+) regulatory T (Treg) cells hydrolyze exogenous adenosine triphosphate (ATP) and participate in immunosuppressive adenosine production. They contain two T-cell subsets whose role in mediating suppression is not understood. Frequencies of both CD4(+) CD39(+) subsets were evaluated in peripheral blood lymphocytes of 57 cancer patients and in tumor infiltrating lymphocytes (TILs) of 6 patients. CD4(+) CD39(+) and CD4(+) CD39(neg) T cells isolated using immunobeads and cell sorting were cultured under various conditions. Their conversion into CD39(+) FOXP3(+) CD25(+) or CD39(+) FOX(neg) CD25(neg) cells was monitored by multiparameter flow cytometry. Hydrolysis of exogenous ATP was measured in luminescence assays. Two CD4(+) CD39(+) cell subsets differing in expression of CD25, FOXP3, CTLA-4, CD121a, PD-1, latency associated peptide (LAP), glycoprotein A repetitions predominant (GARP), and the cytokine profile accumulated with equal frequencies in the blood and tumor tissues of cancer patients. The frequency of both subsets was significantly increased in cancer. CD39 expression levels correlated with the subsets' ability to hydrolyze ATP. Conventional CD4(+) CD39(neg) T cells incubated with IL-2 + TGF-β expanded to generate CD4(+) CD39(+) FOXP3(+) Treg cells, while CD4(+) CD39(+) FOXP3(neg) CD25(neg) subset cells stimulated via the TCR and IL-2 converted to FOXP3(+) CTLA4(+) CD25(+) TGF-β-expressing Treg cells. Among CD4(+) CD39(+) Treg cells, the CD4(+) CD39(+) FOXP3(neg) CD25(neg) subset serves as a reservoir of cells able to convert to Treg cells upon activation by environmental signals. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pulmonary CCR2+CD4+ T cells are immune regulatory and attenuate lung fibrosis development.

PubMed

Milger, Katrin; Yu, Yingyan; Brudy, Eva; Irmler, Martin; Skapenko, Alla; Mayinger, Michael; Lehmann, Mareike; Beckers, Johannes; Reichenberger, Frank; Behr, Jürgen; Eickelberg, Oliver; Königshoff, Melanie; Krauss-Etschmann, Susanne

2017-11-01

Animal models have suggested that CCR2-dependent signalling contributes to the pathogenesis of pulmonary fibrosis, but global blockade of CCL2 failed to improve the clinical course of patients with lung fibrosis. However, as levels of CCR2 + CD4 + T cells in paediatric lung fibrosis had previously been found to be increased, correlating with clinical symptoms, we hypothesised that distinct CCR2 + cell populations might either increase or decrease disease pathogenesis depending on their subtype. To investigate the role of CCR2 + CD4 + T cells in experimental lung fibrosis and in patients with idiopathic pulmonary fibrosis and other fibrosis. Pulmonary CCR2 + CD4 + T cells were analysed using flow cytometry and mRNA profiling, followed by in silico pathway analysis, in vitro assays and adoptive transfer experiments. Frequencies of CCR2 + CD4 + T cells were increased in experimental fibrosis-specifically the CD62L - CD44 + effector memory T cell phenotype, displaying a distinct chemokine receptor profile. mRNA profiling of isolated CCR2 + CD4 + T cells from fibrotic lungs suggested immune regulatory functions, a finding that was confirmed in vitro using suppressor assays. Importantly, adoptive transfer of CCR2 + CD4 + T cells attenuated fibrosis development. The results were partly corroborated in patients with lung fibrosis, by showing higher percentages of Foxp3 + CD25 + cells within bronchoalveolar lavage fluid CCR2 + CD4 + T cells as compared with CCR2 - CD4 + T cells. Pulmonary CCR2 + CD4 + T cells are immunosuppressive, and could attenuate lung inflammation and fibrosis. Therapeutic strategies completely abrogating CCR2-dependent signalling will therefore also eliminate cell populations with protective roles in fibrotic lung disease. This emphasises the need for a detailed understanding of the functions of immune cell subsets in fibrotic lung disease. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

mTOR Complex Signaling through the SEMA4A-Plexin B2 Axis Is Required for Optimal Activation and Differentiation of CD8+ T Cells.

PubMed

Ito, Daisuke; Nojima, Satoshi; Nishide, Masayuki; Okuno, Tatsusada; Takamatsu, Hyota; Kang, Sujin; Kimura, Tetsuya; Yoshida, Yuji; Morimoto, Keiko; Maeda, Yohei; Hosokawa, Takashi; Toyofuku, Toshihiko; Ohshima, Jun; Kamimura, Daisuke; Yamamoto, Masahiro; Murakami, Masaaki; Morii, Eiichi; Rakugi, Hiromi; Isaka, Yoshitaka; Kumanogoh, Atsushi

2015-08-01

Mammalian target of rapamycin (mTOR) plays crucial roles in activation and differentiation of diverse types of immune cells. Although several lines of evidence have demonstrated the importance of mTOR-mediated signals in CD4(+) T cell responses, the involvement of mTOR in CD8(+) T cell responses is not fully understood. In this study, we show that a class IV semaphorin, SEMA4A, regulates CD8(+) T cell activation and differentiation through activation of mTOR complex (mTORC) 1. SEMA4A(-/-) CD8(+) T cells exhibited impairments in production of IFN-γ and TNF-α and induction of the effector molecules granzyme B, perforin, and FAS-L. Upon infection with OVA-expressing Listeria monocytogenes, pathogen-specific effector CD8(+) T cell responses were significantly impaired in SEMA4A(-/-) mice. Furthermore, SEMA4A(-/-) CD8(+) T cells exhibited reduced mTORC1 activity and elevated mTORC2 activity, suggesting that SEMA4A is required for optimal activation of mTORC1 in CD8(+) T cells. IFN-γ production and mTORC1 activity in SEMA4A(-/-) CD8(+) T cells were restored by administration of recombinant Sema4A protein. In addition, we show that plexin B2 is a functional receptor of SEMA4A in CD8(+) T cells. Collectively, these results not only demonstrate the role of SEMA4A in CD8(+) T cells, but also reveal a novel link between a semaphorin and mTOR signaling. Copyright © 2015 by The American Association of Immunologists, Inc.

Prolonged CD4 T Cell Lymphopenia Increases Morbidity and Mortality after Renal Transplantation

PubMed Central

Courivaud, Cécile; Bamoulid, Jamal; Vivet, Bérengère; Chabroux, Aline; Deschamps, Marina; Rebibou, Jean-Michel; Ferrand, Christophe; Chalopin, Jean-Marc; Tiberghien, Pierre; Saas, Philippe

2010-01-01

Prolonged CD4 T cell lymphopenia after administration of polyclonal anti-thymocyte globulins increases the rate of posttransplantation morbidity, but whether impaired immune reconstitution affects survival is unknown. We studied the effect of CD4 T cell lymphopenia on survival in 302 consecutive prevalent renal transplant recipients and the role of thymic function in CD4 T cell reconstitution and posttransplantation outcomes in 100 consecutive incident renal transplant recipients. We followed the prevalent cohort for a mean duration of 92 months. Of these 302 patients, 81 (27%) had persistent CD4 T cell counts <300/mm3 and 36 (12%) died during follow-up. We observed a higher death rate in patients with CD4 T cell lymphopenia persisting for >1 year (24.1 versus 7.6%; P < 0.001). Furthermore, in Cox regression analysis, CD4 T cell lymphopenia associated with a nearly five-fold risk for death (adjusted hazard ratio [HR] 4.63; 95% confidence interval [CI] 1.91 to 10.65; P = 0.001). In the incident cohort, we estimated thymic function by T cell receptor excision circles (TRECs) per 150,000 CD3+ cells, which predicted efficient CD4 T cell reconstitution. Higher pretransplantation TREC values associated with lower risks for cancer (adjusted HR 0.39; 95% CI 0.15 to 0.97; P = 0.046) and infection (HR 0.29; 95% CI 0.11 to 0.78; P = 0.013). In summary, prolonged polyclonal anti-thymocyte globulin–induced CD4 T cell lymphopenia is an independent risk factor for death. Determination of pretransplantation thymic function may identify patients at higher risk for CD4 T cell lymphopenia and posttransplantation morbidity, including cancer and infections. PMID:20203160

Prolonged CD4 T cell lymphopenia increases morbidity and mortality after renal transplantation.

PubMed

Ducloux, Didier; Courivaud, Cécile; Bamoulid, Jamal; Vivet, Bérengère; Chabroux, Aline; Deschamps, Marina; Rebibou, Jean-Michel; Ferrand, Christophe; Chalopin, Jean-Marc; Tiberghien, Pierre; Saas, Philippe

2010-05-01

Prolonged CD4 T cell lymphopenia after administration of polyclonal anti-thymocyte globulins increases the rate of posttransplantation morbidity, but whether impaired immune reconstitution affects survival is unknown. We studied the effect of CD4 T cell lymphopenia on survival in 302 consecutive prevalent renal transplant recipients and the role of thymic function in CD4 T cell reconstitution and posttransplantation outcomes in 100 consecutive incident renal transplant recipients. We followed the prevalent cohort for a mean duration of 92 months. Of these 302 patients, 81 (27%) had persistent CD4 T cell counts <300/mm3 and 36 (12%) died during follow-up. We observed a higher death rate in patients with CD4 T cell lymphopenia persisting for >1 year (24.1 versus 7.6%; P < 0.001). Furthermore, in Cox regression analysis, CD4 T cell lymphopenia associated with a nearly five-fold risk for death (adjusted hazard ratio [HR] 4.63; 95% confidence interval [CI] 1.91 to 10.65; P = 0.001). In the incident cohort, we estimated thymic function by T cell receptor excision circles (TRECs) per 150,000 CD3+ cells, which predicted efficient CD4 T cell reconstitution. Higher pretransplantation TREC values associated with lower risks for cancer (adjusted HR 0.39; 95% CI 0.15 to 0.97; P = 0.046) and infection (HR 0.29; 95% CI 0.11 to 0.78; P = 0.013). In summary, prolonged polyclonal anti-thymocyte globulin-induced CD4 T cell lymphopenia is an independent risk factor for death. Determination of pretransplantation thymic function may identify patients at higher risk for CD4 T cell lymphopenia and posttransplantation morbidity, including cancer and infections.

Enhanced expression of PD-1 and other activation markers by CD4+ T cells of young but not old patients with metastatic melanoma.

PubMed

van den Brom, Rob R H; van der Geest, Kornelis S M; Brouwer, Elisabeth; Hospers, Geke A P; Boots, Annemieke M H

2018-06-01

The biological behavior of melanoma is unfavorable in the elderly when compared to young subjects. We hypothesized that differences in T-cell responses might underlie the distinct behavior of melanoma in young and old melanoma patients. Therefore, we investigated the circulating T-cell compartment of 34 patients with metastatic melanoma and 42 controls, which were classified as either young or old. Absolute numbers of CD4+ T cells were decreased in young and old melanoma patients when compared to the age-matched control groups. Percentages of naive and memory CD4+ T cells were not different when comparing old melanoma patients to age-matched controls. Percentages of memory CD4+ T cells tended to be increased in young melanoma patients compared to young controls. Proportions of naive CD4+ T cells were lower in young patients than in age-matched controls, and actually comparable to those in old patients and controls. This was accompanied with increased percentages of memory CD4+ T cells expressing HLA-DR, Ki-67, and PD-1 in young melanoma patients in comparison to the age-matched controls, but not in old patients. Proportions of CD45RA-FOXP3 high memory regulatory T cells were increased in young and old melanoma patients when compared to their age-matched controls, whereas those of CD45RA+FOXP3 low naive regulatory T cells were similar. We observed no clear modulation of the circulating CD8+ T-cell repertoire in melanoma patients. In conclusion, we show that CD4+ T cells of young melanoma patients show signs of activation, whereas these signs are less clear in CD4+ T cells of old patients.

Chronic exposure to water pollutant trichloroethylene increased epigenetic drift in CD4(+) T cells.

PubMed

Gilbert, Kathleen M; Blossom, Sarah J; Erickson, Stephen W; Reisfeld, Brad; Zurlinden, Todd J; Broadfoot, Brannon; West, Kirk; Bai, Shasha; Cooney, Craig A

2016-05-01

Autoimmune disease and CD4(+) T-cell alterations are induced in mice exposed to the water pollutant trichloroethylene (TCE). We examined here whether TCE altered gene-specific DNA methylation in CD4(+) T cells as a possible mechanism of immunotoxicity. Naive and effector/memory CD4(+) T cells from mice exposed to TCE (0.5 mg/ml in drinking water) for 40 weeks were examined by bisulfite next-generation DNA sequencing. A probabilistic model calculated from multiple genes showed that TCE decreased methylation control in CD4(+) T cells. Data from individual genes fitted to a quadratic regression model showed that TCE increased gene-specific methylation variance in both CD4 subsets. TCE increased epigenetic drift of specific CpG sites in CD4(+) T cells.

Rapid generation of combined CMV-specific CD4+ and CD8+ T-cell lines for adoptive transfer into recipients of allogeneic stem cell transplants.

PubMed

Rauser, Georg; Einsele, Hermann; Sinzger, Christian; Wernet, Dorothee; Kuntz, Gabriele; Assenmacher, Mario; Campbell, John D M; Topp, Max S

2004-05-01

Adoptive transfer of cytomegalovirus (CMV)-specific T cells can restore long-lasting, virus-specific immunity and clear CMV viremia in recipients of allogeneic stem cell transplants if CD4(+) and CD8(+) CMV-specific T cells are detected in the recipient after transfer. Current protocols for generating virus-specific T cells use live virus, require leukapheresis of the donor, and are time consuming. To circumvent these limitations, a clinical-scale protocol was developed to generate CMV-specific T cells by using autologous cellular and serum components derived from a single 500-mL blood draw. CMV-specific T cells were stimulated simultaneously with CMV-specific major histocompatibility complex class I (MHC I)- restricted peptides and CMV antigen. Activated T cells were isolated with the interferon-gamma (IFN-gamma) secretion assay and expanded for 10 days. In 8 randomly selected, CMV-seropositive donors, 1.34 x 10(8) combined CD4(+) and CD8(+) CMV-specific T cells, on average, were generated, as determined by antigen-triggered IFN-gamma production. CMV-infected fibroblasts were efficiently lysed by the generated T cells, and CMV-specific CD4(+) and CD8(+) T cells expanded if they were stimulated with natural processed antigen. On the other hand, CD4(+) and CD8(+) T cell-mediated alloreactivity of generated CMV-specific T-cell lines was reduced compared with that of the starting population. In conclusion, the culture system developed allowed the rapid generation of allodepleted, highly enriched, combined CD4(+) and CD8(+) CMV-specific T cells under conditions mimicking good manufacturing practice.

Bystander CD4+ T lymphocytes survive in HIV-infected human lymphoid tissue

NASA Technical Reports Server (NTRS)

Grivel, Jean-Charles; Biancotto, Angelique; Ito, Yoshinori; Lima, Rosangela G.; Margolis, Leonid B.

2003-01-01

HIV infection is associated with depletion of CD4(+) T cells. The mechanisms of this phenomenon remain to be understood. In particular, it remains controversial whether and to what extent uninfected ("bystander") CD4(+) T cells die in HIV-infected individuals. We address this question using a system of human lymphoid tissue ex vivo. Tissue blocks were inoculated with HIV-1. After productive infection was established, they were treated with the reverse transcriptase inhibitor nevirapine to protect from infection those CD4(+) T cells that had not yet been infected. These CD4(+) T cells residing in HIV-infected tissue are by definition bystanders. Our results demonstrate that after nevirapine application the number of bystander CD4(+) T cells is conserved. Thus, in the context of HIV-infected human lymphoid tissue, productive HIV infection kills infected cells but is not sufficient to cause the death of a significant number of uninfected CD4(+) T cells.

Impact of alemtuzumab on HIV persistence in an HIV-infected individual on antiretroviral therapy with Sezary syndrome.

PubMed

Rasmussen, Thomas A; McMahon, James; Chang, J Judy; Symons, Jori; Roche, Michael; Dantanarayana, Ashanti; Okoye, Afam; Hiener, Bonnie; Palmer, Sarah; Lee, Wen Shi; Kent, Stephen J; Van Der Weyden, Carrie; Prince, H Miles; Cameron, Paul U; Lewin, Sharon R

2017-08-24

To study the effects of alemtuzumab on HIV persistence in an HIV-infected individual on antiretroviral therapy (ART) with Sezary syndrome, a rare malignancy of CD4 T cells. Case report. Blood was collected 30 and 18 months prior to presentation with Sezary syndrome, at the time of presentation and during alemtuzumab. T-cell subsets in malignant (CD7-CD26-TCR-VBeta2+) and nonmalignant cells were quantified by flow cytometry. HIV-DNA in total CD4 T cells, in sorted malignant and nonmalignant CD4 T cells, was quantified by PCR and clonal expansion of HIV-DNA assessed by full-length next-generation sequencing. HIV-hepatitis B virus coinfection was diagnosed and antiretroviral therapy initiated 4 years prior to presentation with Sezary syndrome and primary cutaneous anaplastic large cell lymphoma. The patient received alemtuzumab 10 mg three times per week for 4 weeks but died 6 weeks post alemtuzumab. HIV-DNA was detected in nonmalignant but not in malignant CD4 T cells, consistent with expansion of a noninfected CD4 T-cell clone. Full-length HIV-DNA sequencing demonstrated multiple defective viruses but no identical or expanded sequences. Alemtuzumab extensively depleted T cells, including more than 1 log reduction in total T cells and more than 3 log reduction in CD4 T cells. Finally, alemtuzumab decreased HIV-DNA in CD4 T cells by 57% but HIV-DNA remained detectable at low levels even after depletion of nearly all CD4 T cells. Alemtuzumab extensively depleted multiple T-cell subsets and decreased the frequency of but did not eliminate HIV-infected CD4 T cells. Studying the effects on HIV persistence following immune recovery in HIV-infected individuals who require alemtuzumab for malignancy or in animal studies may provide further insights into novel cure strategies.

Preferential susceptibility of Th9 and Th2 CD4+ T cells to X4-tropic HIV-1 infection.

PubMed

Orlova-Fink, Nina; Chowdhury, Fatema Z; Sun, Xiaoming; Harrington, Sean; Rosenberg, Eric S; Yu, Xu G; Lichterfeld, Mathias

2017-10-23

The functional polarization of CD4 T cells determines their antimicrobial effector profile, but may also impact the susceptibility to infection with HIV-1. Here, we analyzed the susceptibility of CD4 T cells with different functional polarization to infection with X4 and R5-tropic HIV-1. CD4 T cells with a Th1, Th2, Th17, and Th9 polarization were subjected to in-vitro infection assays with X4, R5, or vesicular stomatitis virus-G protein-pseudotyped HIV-1. In addition, we sorted differentially polarized CD4 T-cell subsets from individuals treated with antiretroviral therapy and analyzed the tropism of viral env sequences. Th9-polarized CD4 T cells and, to a lesser extent, Th2-polarized CD4 T cells expressed higher surface levels of CXCR4, and are more permissive to X4-tropic infection in vitro. In contrast, Th1 and Th17 CD4 T cells exhibited stronger surface expression of CCR5, and were more susceptible to infection with R5-tropic viruses. Correspondingly, the distribution of X4-tropic viral sequences in antiretroviral therapy-treated HIV-1-infected patients was biased toward Th9/Th2 cells, whereas R5-tropic sequences were more frequently observed in Th17 cells. CD4 T-cell polarization is associated with a distinct susceptibility to X4 and R5-tropic HIV-1 infection.

Early stages in the development of human T, natural killer and thymic dendritic cells.

PubMed

Spits, H; Blom, B; Jaleco, A C; Weijer, K; Verschuren, M C; van Dongen, J J; Heemskerk, M H; Res, P C

1998-10-01

T-cell development is initiated when CD34+ pluripotent stem cells or their immediate progeny leave the bone marrow to migrate to the thymus. Upon arrival in the thymus the stem cell progeny is not yet committed to the T-cell lineage as it has the capability to develop into T, natural killer (NK) and dendritic cells (DC). Primitive hematopoietic progenitor cells in the human thymus express CD34 and lack CD1a. When these progenitor cells develop into T cells they traverse a number of checkpoints. One early checkpoint is the induction of T-cell commitment, which correlates with appearance of CD1a and involves the loss of capacity to develop into NK cells and DC and the initiation of T-cell receptor (TCR) gene rearrangements. Basic helix-loop-helix transcription factors play a role in induction of T-cell commitment. CD1a+CD34+ cells develop into CD4+CD8 alpha+ beta+ cells by upregulating first CD4, followed by CD8 alpha and then CD8 beta. Selection for productive TCR beta gene rearrangements (beta selection) likely occurs in the CD4+CD8 alpha+ beta- and CD4+CD8 alpha+ beta+ populations. Although the T and NK-cell lineages are closely related to each other, NK cells can develop independently of the thymus. The fetal thymus is most likely one site of NK-cell development.

[Regulatory B cells activated by CpG-ODN combined with anti-CD40 monoclonal antibody inhibit CD4(+)T cell proliferation].

PubMed

Wang, Keng; Tao, Lei; Su, Jianbing; Zhang, Yueyang; Zou, Binhua; Wang, Yiyuan; Li, Xiaojuan

2016-09-01

Objective To observe the immunosuppressive function of regulatory B cells (Bregs) in vitro after activated by CpG oligodeoxynucleotide (CpG-ODN) and anti-CD40 mAb. Methods Mice splenic CD5(+)CD1d(high)B cells and CD5(-)CD1d(low)B cells were sorted by flow cytometry. These B cells were first stimulated with CpG-ODN combined with anti-CD40 mAb for 24 hours, and then co-cultured with purified CD4(+)T cells. The interleukin 10 (IL-10) expression in the activated Bregs and other B cell subset, as well as the proliferation and interferon γ (IFN-γ) expression in the CD4(+) T cells activated by anti-CD3 mAb plus anti-CD28 mAb were determined by flow cytometry. Results CD5(+)CD1d(high) B cells activated by CpG-ODN plus anti-CD40 mAb blocked the up-regulated CD4(+)T proliferation and significantly reduced the IFN-γ level. At the same time, activated CD5(-)CD1d(low)B cells showed no inhibitory effect on CD4(+)T cells. Further study revealed that IL-10 expression in the CD5(+)CD1d(high) B cells were much higher than that in the CD5(-)CD1d(low)B cells after stimulated with CpG-ODN combined with anti-CD40 mAb for 24 hours. Conclusion CD5(+)CD1d(high) B cells activated by CpG-ODN combined with anti-CD40 mAb have immune inhibitory effects on CD4(+)T cell activation in vitro , which possibly due to IL-10 secretion.

[Application of digital pathology tools. An unusual case of non-Hodgkin lymphoma].

PubMed

Meyer, A-S K; Dallenbach, F E; Lienert, G; Möller, P; Lennerz, J K

2012-11-01

Currently, lymphoma diagnosis is based on a combination of morphology, immunophenotyping, and molecular testing. Using the example of an unusual case of malignant non-Hodgkin lymphoma, we show that improved visualization using digital pathology contributes to the convergence of these complementary diagnostic modalities. A 45-year-old woman presented with skin rash and cervical lymphadenopathy. Histological workup of an excised lymph node showed loss of normal architecture with diffuse infiltration and increased mitotic activity. Immunohistochemistry for CD3/CD5 showed atypical arrangement and infiltration of a T-cell population that dominated over regionally dense, MUM1-positive plasmacellular infiltrates. Expanded CD21/CD23-positive meshworks of follicular dendritic cells were present within and between regressed follicles and the T-cell infiltrate; staining for CD56 and cyclin-D1 was negative. Quantification of Ki-67 staining within the T-, B- and plasmacellular compartments was achieved by digital image conversion, overlay and subsequent quantification algorithms that revealed proliferation within more than 60% of T-cells, over 50% of plasma cells and only 20% of B-cells. Clonality analysis by PCR revealed monoclonal rearrangement for both T-cell receptor gamma chains and immunoglobulin heavy chains. Taken together, we present an unusual combination of an angioimmunoblastic T-cell lymphoma (AITL) and simultaneous plasmacellular lymphoma. This report demonstrates how application of modern tools of digital pathology can visually integrate unusual morphological and molecular findings.

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.

Transcriptome Analysis of Mycobacteria-Specific CD4+ T Cells Identified by Activation-Induced Expression of CD154.

PubMed

Kunnath-Velayudhan, Shajo; Goldberg, Michael F; Saini, Neeraj K; Johndrow, Christopher T; Ng, Tony W; Johnson, Alison J; Xu, Jiayong; Chan, John; Jacobs, William R; Porcelli, Steven A

2017-10-01

Analysis of Ag-specific CD4 + T cells in mycobacterial infections at the transcriptome level is informative but technically challenging. Although several methods exist for identifying Ag-specific T cells, including intracellular cytokine staining, cell surface cytokine-capture assays, and staining with peptide:MHC class II multimers, all of these have significant technical constraints that limit their usefulness. Measurement of activation-induced expression of CD154 has been reported to detect live Ag-specific CD4 + T cells, but this approach remains underexplored and, to our knowledge, has not previously been applied in mycobacteria-infected animals. In this article, we show that CD154 expression identifies adoptively transferred or endogenous Ag-specific CD4 + T cells induced by Mycobacterium bovis bacillus Calmette-Guérin vaccination. We confirmed that Ag-specific cytokine production was positively correlated with CD154 expression by CD4 + T cells from bacillus Calmette-Guérin-vaccinated mice and show that high-quality microarrays can be performed from RNA isolated from CD154 + cells purified by cell sorting. Analysis of microarray data demonstrated that the transcriptome of CD4 + CD154 + cells was distinct from that of CD154 - cells and showed major enrichment of transcripts encoding multiple cytokines and pathways of cellular activation. One notable finding was the identification of a previously unrecognized subset of mycobacteria-specific CD4 + T cells that is characterized by the production of IL-3. Our results support the use of CD154 expression as a practical and reliable method to isolate live Ag-specific CD4 + T cells for transcriptomic analysis and potentially for a range of other studies in infected or previously immunized hosts. Copyright © 2017 by The American Association of Immunologists, Inc.

[Increased expressions of peripheral PD-1+ lymphocytes and CD4+CD25+FOXP3+ T cells in gastric adenocarcinoma patients].

PubMed

Li, Hao; Li, Songyan; Hu, Shidong; Zou, Guijun; Hu, Zilong; Wei, Huahua; Wang, Yufeng; Du, Xiaohui

2017-01-01

Objective To detect the frequencies of peripheral programmed death-1 + (PD-1 + ) lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells in patients with gastric adenocarcinoma. Methods The study enrolled 29 patients with gastric adenocarcinoma and 29 age- and sex-matched healthy controls. Frequencies of PD-1 + lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells were detected using flow cytometry. Results The number of PD-1 + lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells in peripheral blood was higher in patients with gastric adenocarcinoma than that in the control group. Moreover, linear correlation analysis indicated a positive correlation between PD-1 expression and frequency of CD4 + CD25 + FOXP3 + regulatory T cells in peripheral blood of the patients. Conclusion Gastric adenocarcinoma patients present with increased PD-1 + lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells in the peripheral blood.

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

PubMed Central

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

2012-01-01

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

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

PubMed Central

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

2008-01-01

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

Preliminary study of histamine H4 receptor expressed on human CD4+ T cells and its immunomodulatory potency in the IL-17 pathway of psoriasis.

PubMed

Han, Song Hee; Hur, Min Seok; Kim, Min Jung; Kim, Bo Mi; Kim, Kyoung Woon; Kim, Hae Rim; Choe, Yong Beom; Ahn, Kyu Joong; Lee, Yang Won

2017-10-01

Previous studies have shown the expression of histamine H 4 receptor (H4R) on CD4 + T cells, especially human CD4 + T h 2-polarized T cells. This study aimed to investigate the role of H4R on these effector T cells in psoriasis. We enrolled three patients each with active psoriasis, inactive psoriasis, scalp seborrheic dermatitis, and three normal controls, and compared the basal expression of H4R mRNA in their peripheral blood CD4 + T cells. Then, we identified H4R expression in dermal CD4 + T cells. Furthermore, we investigated H4R expression after stimulating separated peripheral blood CD4 + T cells with several inflammatory cytokines. The results showed higher H4R expression in the active psoriasis group compared to the inactive psoriasis group. It was interesting that interleukin (IL)-23, which is a representative cytokine contributing to T h 17 cell differentiation, stimulated H4R expression significantly. After adding a selective H4R antagonist (JNJ-7777120) while the CD4 + T cells were polarized into T h 17 cells, we observed a tendency toward suppressed IL-17 secretion. Histamine stimulation influences the IL-17 pathway in psoriasis via the fourth histamine receptor subtype, H4R, on CD4 + T cells. The immunomodulatory roles of H4R suggest its potency as a new therapeutic target for obstinate psoriasis. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

Characteristics of HIV target CD4 T cells collected using different sampling methods from the genital tract of HIV seronegative women.

PubMed

Iyer, Smita S; Sabula, Michael J; Mehta, C Christina; Haddad, Lisa B; Brown, Nakita L; Amara, Rama R; Ofotokun, Igho; Sheth, Anandi N

2017-01-01

Understanding the immune profile of CD4 T cells, the primary targets for HIV, in the female genital tract (FGT) is critical for evaluating and developing effective biomedical HIV prevention strategies in women. However, longitudinal investigation of HIV susceptibility markers expressed by FGT CD4 T cells has been hindered by low cellular yield and risk of sampling-associated trauma. We investigated three minimally invasive FGT sampling methods to characterize and compare CD4 T cell yield and phenotype with the goal of establishing feasible sampling strategies for immune profiling of mucosal CD4 T cells. FGT samples were collected bimonthly from 12 healthy HIV negative women of reproductive age in the following order: 1) Cervicovaginal lavage (CVL), 2) two sequential endocervical flocked swabs (FS), and 3) two sequential endocervical cytobrushes (CB1, CB2). Cells were isolated and phentoyped via flow cytometry. CD4 T cell recovery was highest from each individual CB compared to either CVL or FS (p < 0.0001). The majority of CD4 T cells within the FGT, regardless of sampling method, expressed CCR5 relative to peripheral blood (p < 0.01). Within the CB, CCR5+ CD4 T cells expressed significantly higher levels of α4β7, CD69, and low levels of CD27 relative to CCR5- CD4 T cells (all p < 0.001). We also identified CD4 Treg lineage cells expressing CCR5 among CB samples. Using three different mucosal sampling methods collected longitudinally we demonstrate that CD4 T cells within the FGT express CCR5 and α4β7 and are highly activated, attributes which could act in concert to facilitate HIV acquisition. FS and CB sampling methods can allow for investigation of strategies to reduce HIV target cells in the FGT and could inform the design and interpretation microbicide and vaccine studies in women.

[An analysis of immunophenotyping of peripheral lymphocytes in adult patients with infectious mononucleosis and chronic active Epstein-Barr virus infection].

PubMed

Xie, J; Wang, H L; Qiu, Z F; Li, T S

2016-06-01

To determine the immunophenotypic features of peripheral lymphocytes in adult patients with Epstein-Barr virus(EBV)-associated infectious mononucleosis(IM) and chronic active EBV infection (CAEBV). Eighteen IM patients, 12 CAEBV patients and 18 healthy donors were included. Lymphocyte subsets including CD3(-)CD19(+) B cells, CD3(-)CD16/56(+) NK cells, CD4(+) and CD8(+) T cells in peripheral blood were measured by flow cytometry. The expression of activation markers (HLA-DR and CD38) on CD8(+) T cells and CD28 expression on T cells were also determined. Kruskal-Wallis H and Mann-Whitney U tests were used to compare variables among groups. IM patients had dramatically increased CD8(+) T cell counts than healthy donors (5.22×10(9)/L vs 0.54×10(9)/L, P<0.001). B cell counts moderately reduced in patients with IM than in healthy donors. No difference was found in absolute CD4(+) T cell and NK cell counts between IM and healthy donors. The levels of HLA-DR and CD38 on CD8(+) T cells significantly increased in IM patients compared with those in healthy controls. The intensity of CD28 on CD8(+) T cells significantly decreased, which was not seen on CD4(+) T cells. The median cell counts of B, NK, CD4(+) T and CD8(+) T subsets in CAEBV patients were 0.02×10(9)/L, 0.06×10(9)/L, 0.26×10(9)/L and 0.21×10(9)/L respectively, which were significantly lower than those in healthy donors (0.22×10(9)/L, 0.38×10(9)/L, 0.78×10(9)/L, 0.54×10(9)/L)and IM patients (0.12×10(9)/L, 0.40×10(9)/L, 0.91×10(9)/L, 5.22×10(9)/L). The positive rates of HLA-DR and CD38 on CD8(+) T cells in CAEBV patients were higher than those in healthy controls, but lower than those in IM patients. The immunophenotypic pattern in adult patients with IM is characterized by a dramatic increase of extensively activated CD8(+) T cells, a moderate reduction of CD19(+) B cells and no significant change of CD4(+) T cells and CD16/56(+) NK cells. CAEBV is featured by an immunosuppression status as demonstrated by significantly decreased B, NK, CD4(+) T and CD8(+) T subsets.

Adipose-derived stem cells were impaired in restricting CD4+T cell proliferation and polarization in type 2 diabetic ApoE-/- mouse.

PubMed

Liu, Ming-Hao; Li, Ya; Han, Lu; Zhang, Yao-Yuan; Wang, Di; Wang, Zhi-Hao; Zhou, Hui-Min; Song, Ming; Li, Yi-Hui; Tang, Meng-Xiong; Zhang, Wei; Zhong, Ming

2017-07-01

Atherosclerosis (AS) is the most common and serious complication of type 2 diabetes mellitus (T2DM) and is accelerated via chronic systemic inflammation rather than hyperglycemia. Adipose tissue is the major source of systemic inflammation in abnormal metabolic state. Pro-inflammatory CD4 + T cells play pivotal role in promoting adipose inflammation. Adipose-derived stem cells (ADSCs) for fat regeneration have potent ability of immunosuppression and restricting CD4 + T cells as well. Whether T2DM ADSCs are impaired in antagonizing CD4 + T cell proliferation and polarization remains unclear. We constructed type 2 diabetic ApoE -/- mouse models and tested infiltration and subgroups of CD4 + T cell in stromal-vascular fraction (SVF) in vivo. Normal/T2DM ADSCs and normal splenocytes with or without CD4 sorting were separated and co-cultured at different scales ex vivo. Immune phenotypes of pro- and anti-inflammation of ADSCs were also investigated. Flow cytometry (FCM) and ELISA were applied in the experiments above. CD4 + T cells performed a more pro-inflammatory phenotype in adipose tissue in T2DM ApoE -/- mice in vivo. Restriction to CD4 + T cell proliferation and polarization was manifested obviously weakened after co-cultured with T2DM ADSCs ex vivo. No obvious distinctions were found in morphology and growth type of both ADSCs. However, T2DM ADSCs acquired a pro-inflammatory immune phenotype, with secreting less PGE2 and expressing higher MHC-II and co-stimulatory molecules (CD40, CD80). Normal ADSCs could also obtain the phenotypic change after cultured with T2DM SVF supernatant. CD4 + T cell infiltration and pro-inflammatory polarization exist in adipose tissue in type 2 diabetic ApoE -/- mice. T2DM ADSCs had impaired function in restricting CD4 + T lymphocyte proliferation and pro-inflammatory polarization due to immune phenotypic changes. Copyright © 2017 Elsevier Ltd. All rights reserved.

CD32-Expressing CD4 T Cells Are Phenotypically Diverse and Can Contain Proviral HIV DNA.

PubMed

Martin, Genevieve E; Pace, Matthew; Thornhill, John P; Phetsouphanh, Chansavath; Meyerowitz, Jodi; Gossez, Morgane; Brown, Helen; Olejniczak, Natalia; Lwanga, Julianne; Ramjee, Gita; Kaleebu, Pontiano; Porter, Kholoud; Willberg, Christian B; Klenerman, Paul; Nwokolo, Nneka; Fox, Julie; Fidler, Sarah; Frater, John

2018-01-01

Efforts to both characterize and eradicate the HIV reservoir have been limited by the rarity of latently infected cells and the absence of a specific denoting biomarker. CD32a (FcγRIIa) has been proposed to be a marker for an enriched CD4 T cell HIV reservoir, but this finding remains controversial. Here, we explore the expression of CD32 on CD3 + CD4 + cells in participants from two primary HIV infection studies and identify at least three distinct phenotypes (CD32 low , CD32 + CD14 + , and CD32 high ). Of note, CD4 negative enrichment kits remove the majority of CD4 + CD32 + T cells, potentially skewing subsequent analyses if used. CD32 high CD4 T cells had higher levels of HLA-DR and HIV co-receptor expression than other subsets, compatible with their being more susceptible to infection. Surprisingly, they also expressed high levels of CD20, TCRαβ, IgD, and IgM (but not IgG), markers for both T cells and naïve B cells. Compared with other populations, CD32 low cells had a more differentiated memory phenotype and high levels of immune checkpoint receptors, programmed death receptor-1 (PD-1), Tim-3, and TIGIT. Within all three CD3 + CD4 + CD32 + phenotypes, cells could be identified in infected participants, which contained HIV DNA. CD32 expression on CD4 T cells did not correlate with HIV DNA or cell-associated HIV RNA (both surrogate measures of overall reservoir size) or predict time to rebound viremia following treatment interruption, suggesting that it is not a dominant biomarker for HIV persistence. Our data suggest that while CD32 + T cells can be infected with HIV, CD32 is not a specific marker of the reservoir although it might identify a population of HIV enriched cells in certain situations.

Vaccination with live attenuated simian immunodeficiency virus causes dynamic changes in intestinal CD4+CCR5+ T cells

PubMed Central

2011-01-01

Background Vaccination with live attenuated SIV can protect against detectable infection with wild-type virus. We have investigated whether target cell depletion contributes to the protection observed. Following vaccination with live attenuated SIV the frequency of intestinal CD4+CCR5+ T cells, an early target of wild-type SIV infection and destruction, was determined at days 3, 7, 10, 21 and 125 post inoculation. Results In naive controls, modest frequencies of intestinal CD4+CCR5+ T cells were predominantly found within the LPL TTrM-1 and IEL TTrM-2 subsets. At day 3, LPL and IEL CD4+CCR5+ TEM cells were dramatically increased whilst less differentiated subsets were greatly reduced, consistent with activation-induced maturation. CCR5 expression remained high at day 7, although there was a shift in subset balance from CD4+CCR5+ TEM to less differentiated TTrM-2 cells. This increase in intestinal CD4+CCR5+ T cells preceded the peak of SIV RNA plasma loads measured at day 10. Greater than 65.9% depletion of intestinal CD4+CCR5+ T cells followed at day 10, but overall CD4+ T cell homeostasis was maintained by increased CD4+CCR5- T cells. At days 21 and 125, high numbers of intestinal CD4+CCR5- naive TN cells were detected concurrent with greatly increased CD4+CCR5+ LPL TTrM-2 and IEL TEM cells at day 125, yet SIV RNA plasma loads remained low. Conclusions This increase in intestinal CD4+CCR5+ T cells, following vaccination with live attenuated SIV, does not correlate with target cell depletion as a mechanism of protection. Instead, increased intestinal CD4+CCR5+ T cells may correlate with or contribute to the protection conferred by vaccination with live attenuated SIV. PMID:21291552

CD4 T cell subsets in the Mucosa are CD28+Ki-67−HLA-DR−CD69+ but show differential infection based on α4β7 receptor expression during acute SIV infection

PubMed Central

Kader, Muhamuda; Bixler, Sandra; Roederer, Mario; Veazey, Ronald; Mattapallil, Joseph J.

2009-01-01

Background CD4 T cell depletion in the mucosa has been well documented during acute HIV and SIV infections. The demonstration the HIV/SIV can use the α4β7 receptor for viral entry suggests that these viruses selectively target CD4 T cells in the mucosa that express high levels of α4β7 receptor. Methods Mucosal samples obtained from SIV infected rhesus macaques during the early phase of infection were used for immunophenotypic analysis. CD4 T cell subsets were sorted based on the expression of β7 and CD95 to quantify the level of SIV infection in different subsets of CD4 T cells. Changes in IL-17, IL-21, IL-23 and TGFβ mRNA expression was determined using Taqman PCR. Results CD4 T cells in the mucosa were found to harbor two major population of cells; ~25% of CD4 T cells expressed the α4+β7hi phenotype, whereas the rest of the 75% expressed an α4+β7int phenotype. Both the subsets were predominantly CD28+Ki-67− HLA-DR− but CD69+, and expressed detectable levels of CCR5 on their surface. Interestingly, however, α4+β7hiCD4 T cells were found to harbor more SIV than the α4+β7int subsets at day 10 pi. Early infection was associated with a dramatic increase in the expression of IL-17, and IL-17 promoting cytokines IL-21, IL-23, and TGFβ that stayed high even after the loss of mucosal CD4 T cells. Conclusions Our results suggest that the differential expression of the α4β7 receptor contributes to the differences in the extent of infection in CD4 T cell subsets in the mucosa. Early infection associated dysregulation of the IL-17 network in mucosal tissues involves other non-Th-17 cells that likely contributes to the pro-inflammatory environment in the mucosa during acute stages of SIV infection. PMID:19863675

Different thresholds of T cell activation regulate FIV infection of CD4{sup +}CD25{sup +} and CD4{sup +}CD25{sup -} cells

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

Joshi, Anjali; Garg, Himanshu; Tompkins, Mary B.

2005-05-10

Cellular activation plays an important role in retroviral replication. Previously, we have shown that CD4{sup +}CD25{sup +} T cells by the virtue of their partially activated phenotype represent ideal candidates for a productive feline immunodeficiency virus (FIV) infection. In the present study, we extended our previous observations with regard to FIV replication in CD4{sup +}CD25{sup +} and CD4{sup +}CD25{sup -} cells under different stimulation conditions. Both CD4{sup +}CD25{sup +} and CD4{sup +}CD25{sup -} cells remain latently infected in the absence of IL-2 or concanvalinA (ConA), respectively; harboring a replication competent provirus capable of reactivation several days post-infection. While CD4{sup +}CD25{supmore » +} cells require low levels of exogenous IL-2 and virus inputs for an efficient FIV replication, CD4{sup +}CD25{sup -} T cells can only be productively infected in the presence of either high concentrations of IL-2 or high virus titers, even in the absence of mitogenic stimulation. Interestingly, while high virus input activates CD4{sup +}CD25{sup -} cells to replicate FIV, it induces apoptosis in a high percentage of CD4{sup +}CD25{sup +} T cells. High IL-2 concentrations but not high virus inputs lead to surface upregulation of CD25 and significant cellular proliferation in CD4{sup +}CD25{sup -} cells. These results suggest that CD4{sup +}CD25{sup +} and CD4{sup +}CD25{sup -} T cells have different activation requirements which can be modulated by both viral and cytokine stimuli to reach threshold activation levels in order to harbor a productive FIV infection. This holds implications in vivo for CD4{sup +}CD25{sup +} and CD4{sup +}CD25{sup -} cells to serve as potential reservoirs of a productive and latent FIV infection.« less

T-cell immunity and cytokine production in cosmonauts after long-duration space flights

NASA Astrophysics Data System (ADS)

Morukov, B.; Rykova, M.; Antropova, E.; Berendeeva, T.; Ponomaryov, S.; Larina, I.

2011-04-01

Long-duration spaceflight effects on T-cell immunity and cytokine production were studied in 12 Russian cosmonauts flown onto the International Space Station. Specific assays were performed before launch and after landing and included analysis of peripheral leukocyte distribution, analysis of T-cell phenotype, expression of activation markers, apoptosis, proliferation of T cells in response to a mitogen, concentrations of cytokines in supernatants of cell cultures. Statistically significant increase was observed in leukocytes', lymphocytes', monocytes' and granulocytes' total number, increase in percentage and absolutely number of CD3 +CD4 +-cells, CD4 +CD45RA +-cells and CD4 +CD45RA +/CD4 +CD45RО + ratio, CD4 +CD25 +Bright regulatory cells ( p<0,05) in peripheral blood after landing. T-lymphocytes' capacity to present CD69 and CD25 on its own surfaces was increased for the majority of crewmembers. Analysis of T-cell response to PHA-stimulation in vitro revealed there were some trends toward reduced proliferation of stimulated T-lymphocytes. There was an apparent post flight decrease in secreted IFN-g for the majority of crewmembers and in most instances there was elevation in secreted IL-10. It revealed depression of IFN-g/IL-10 ratio after flight. Correlation analysis according to Spearman's rank correlation test established significant positive correlations ( p<0.05) between cytokine production and T-cell activation (CD25+, CD38+) and negative correlation ( p<0.05) between cytokine production and number of bulk memory CD4+T-cells (CD45RO+). Thus, these results suggest that T-cell dysfunction can be conditioned by cytokine dysbalance and could lead to development of disease after long-duration space flights.

The investigation of CD4+T-cell functions in primary HIV infection with antiretroviral therapy

PubMed Central

Sun, Yu; Fu, Yajing; Zhang, Zining; Tang, Tian; Liu, Jing; Ding, Haibo; Han, Xiaoxu; Xu, Junjie; Chu, Zhenxing; Shang, Hong; Jiang, Yongjun

2017-01-01

Abstract Human immunodeficiency virus (HIV) infection leads to reduced CD4+T-cell counts and immune dysfunction. Initiation of antiretroviral therapy (ART) in HIV primary infection has been recommended to achieve an optimal clinical outcome, but a comprehensive study on restoration of CD4+T-cell function in primary HIV-infected individuals with ART still needs to be eluciated. We investigated longitudinal changes in the CD4+T-cell counts, phenotypes, and functions in HIV-infected individuals with early ART (initiated within 6 months after HIV infection) or later ART (initiated more than 12 months after HIV infection). Patients from early ART and later ART groups had received ART for at least 1 year. Individuals with early ART had more CD4+T cells, a faster rate of CD4+T-cell recovery than those receiving later ART; the levels of CD4+T-cell activation and senescence were lower in early ART compared to those with later ART (P = .031; P = .016), but the activation was higher than normal controls (NC) (P = .001); thymic emigrant function was more upregulated in early ART than in later ART (P = .015), but still lower than NC (P = .027); proliferative capacity and interferon-γ secretion of CD4+T cells were significantly decreased in primary infection (P < .001; P = .029), and early ART restored these CD4+T-cell functions, there is no difference with NC, later ART could partially restore the functions of CD4+T cells, but it remained lower than that of NC (P = .005; P = .019). Early ART could better improve CD4+T-cell function. PMID:28700479

Kinetics of CD4+ T cell repopulation of lymphoid tissues after treatment of HIV-1 infection

PubMed Central

Zhang, Zhi-Qiang; Notermans, Daan W.; Sedgewick, Gerald; Cavert, Winston; Wietgrefe, Stephen; Zupancic, Mary; Gebhard, Kristin; Henry, Keith; Boies, Lawrence; Chen, Zongming; Jenkins, Marc; Mills, Roger; McDade, Hugh; Goodwin, Carolyn; Schuwirth, Caspar M.; Danner, Sven A.; Haase, Ashley T.

1998-01-01

Potent combinations of antiretroviral drugs diminish the turnover of CD4+ T lymphocytes productively infected with HIV-1 and reduce the large pool of virions deposited in lymphoid tissue (LT). To determine to what extent suppression of viral replication and reduction in viral antigens in LT might lead correspondingly to repopulation of the immune system, we characterized CD4+ T lymphocyte populations in LT in which we previously had quantitated viral load and turnover of infected cells before and after treatment. We directly measured by quantitative image analysis changes in total CD4+ T cell counts, the CD45RA+ subset, and fractions of proliferating or apoptotic CD4+ T cells. Compared with normal controls, we documented decreased numbers of CD4+ T cells and increased proliferation and apoptosis. After treatment, proliferation returned to normal levels, and total CD4+ T and CD45RA+ cells increased. We discuss the effects of HIV-1 on this subset based on the concept that renewal mechanisms in the adult are operating at full capacity before infection and cannot meet the additional demand imposed by the loss of productively infected cells. The slow increases in the CD45RA+ CD4+ T cells are consistent with the optimistic conclusions that (i) renewal mechanisms have not been damaged irreparably even at relatively advanced stages of infection and (ii) CD4+ T cell populations can be partially restored by control of active replication without eradication of HIV-1. PMID:9448301

Kinetics of CD4+ T cell repopulation of lymphoid tissues after treatment of HIV-1 infection.

PubMed

Zhang, Z Q; Notermans, D W; Sedgewick, G; Cavert, W; Wietgrefe, S; Zupancic, M; Gebhard, K; Henry, K; Boies, L; Chen, Z; Jenkins, M; Mills, R; McDade, H; Goodwin, C; Schuwirth, C M; Danner, S A; Haase, A T

1998-02-03

Potent combinations of antiretroviral drugs diminish the turnover of CD4+ T lymphocytes productively infected with HIV-1 and reduce the large pool of virions deposited in lymphoid tissue (LT). To determine to what extent suppression of viral replication and reduction in viral antigens in LT might lead correspondingly to repopulation of the immune system, we characterized CD4+ T lymphocyte populations in LT in which we previously had quantitated viral load and turnover of infected cells before and after treatment. We directly measured by quantitative image analysis changes in total CD4+ T cell counts, the CD45RA+ subset, and fractions of proliferating or apoptotic CD4+ T cells. Compared with normal controls, we documented decreased numbers of CD4+ T cells and increased proliferation and apoptosis. After treatment, proliferation returned to normal levels, and total CD4+ T and CD45RA+ cells increased. We discuss the effects of HIV-1 on this subset based on the concept that renewal mechanisms in the adult are operating at full capacity before infection and cannot meet the additional demand imposed by the loss of productively infected cells. The slow increases in the CD45RA+ CD4+ T cells are consistent with the optimistic conclusions that (i) renewal mechanisms have not been damaged irreparably even at relatively advanced stages of infection and (ii) CD4+ T cell populations can be partially restored by control of active replication without eradication of HIV-1.

High susceptibility to liver injury in IL-27 p28 conditional knockout mice involves intrinsic interferon-γ dysregulation of CD4+ T cells.

PubMed

Zhang, Song; Liang, Ruifang; Luo, Wei; Liu, Chang; Wu, Xiaoli; Gao, Yanan; Hao, Jianlei; Cao, Guangchao; Chen, Xi; Wei, Jun; Xia, Siyuan; Li, Zheng; Wen, Ti; Wu, Yunyun; Zhou, Xinglong; Wang, Puyue; Zhao, Liqing; Wu, Zhengzhou; Xiong, Sidong; Gao, Xiaoming; Gao, Xiang; Chen, Yongyan; Ge, Qing; Tian, Zhigang; Yin, Zhinan

2013-04-01

Interleukin (IL)-27, a newly discovered IL-12 family cytokine, is composed of p28 and EBI3. In this study, CD11c-p28(f/f) conditional knockout mice were generated to delete p28 specifically in dendritic cells (DCs). We demonstrated that in the absence of DC-derived p28, these mice were highly susceptible to both low and higher concentrations of concanavalin A (ConA) (5 mg/kg or 10 mg/kg), with extremely early and steady high levels of interferon-γ (IFN-γ) in sera. Neutralizing IFN-γ prevented ConA-induced liver damage in these mice, indicating a critical role of IFN-γ in this pathological process. Interestingly, the main source of the increased IFN-γ in CD11c-p28(f/f) mice was CD4+ T cells, but not natural killer T (NKT) cells. Depletion of CD4+ , but not NK1.1+ , cells completely abolished liver damage, whereas transferring CD4+ T cells from CD11c-p28(f/f) mice, but not from wild-type mice or CD11c-p28(f/f) -IFN-γ(-/-) double knockout mice to CD4(-/-) mice, restored the increased liver damage. Further studies defined higher levels of IFN-γ and T-bet messenger RNA in naïve CD4+ T cells from CD11c-p28(f/f) mice, and these CD4+ T cells were highly responsive to both low and higher concentrations of anti-CD3, indicating a programmed functional alternation of CD4+ T cells. We provide a unique model for studying the pathology of CD4+ T cell-mediated liver injury and reveal a novel function of DC-derived p28 on ConA-induced fulminant hepatitis through regulation of the intrinsic ability for IFN-γ production by CD4+ T cells. Copyright © 2012 American Association for the Study of Liver Diseases.

Brief Report: CD14brightCD16- monocytes and sCD14 level negatively associate with CD4-memory T-cell frequency and predict HCV-decline on therapy.

PubMed

Judge, Chelsey J; Sandberg, Johan K; Funderburg, Nicholas T; Sherman, Kenneth E; Butt, Adeel A; Kang, Minhee; Landay, Alan L; Lederman, Michael M; Anthony, Donald D

2016-11-01

During HIV+ hepatitis C virus (HCV)+ coinfection CD14CD16 monocytes produce soluble immune-activation markers that predict disease progression and poor response to interferon (IFN)-α treatment. We evaluated relationships among immune activation, monocyte phenotype, CD4-memory T cells, and HCV-, cytomegalovirus-, and cytomegalovirus/Epstein-Barr virus/influenza-specific IFN-γ-response before and during IFN-α treatment. Effector-memory and central-memory CD4 T-cell frequencies were lower in HCV+ HIV+ donors than in uninfected donors and correlated negatively with HCV level, CD14CD16 monocytes, and plasma sCD14. sCD14 and CD14CD16 monocytes negatively correlated with IFN-α-dependent HCV decline. CD4 effector-memory T cells positively associated with cytomegalovirus/Epstein-Barr virus/influenza(CEF)-specific IFN-γ response, while sCD14 negatively associated with both CD4 effector-memory T cells and CEF-specific IFN-γ response. These data support a role for memory-CD4 T cells in HCV containment and link immune activation and CD14CD16-monocyte frequency to the failure of IFN-dependent HCV clearance.

Cutting edge: high molecular weight hyaluronan promotes the suppressive effects of CD4+CD25+ regulatory T cells.

PubMed

Bollyky, Paul L; Lord, James D; Masewicz, Susan A; Evanko, Stephen P; Buckner, Jane H; Wight, Thomas N; Nepom, Gerald T

2007-07-15

Hyaluronan is a glycosaminoglycan present in the extracellular matrix. When hyaluronan is degraded during infection and injury, low m.w. forms are generated whose interactions influence inflammation and angiogenesis. Intact high m.w. hyaluronan, conversely, conveys anti-inflammatory signals. We demonstrate that high m.w. hyaluronan enhances human CD4(+)CD25(+) regulatory T cell functional suppression of responder cell proliferation, whereas low m.w. hyaluronan does not. High m.w. hyaluronan also up-regulates the transcription factor FOXP3 on CD4(+)CD25(+) regulatory T cells. These effects are only seen with activated CD4(+)CD25(+) regulatory T cells and are associated with the expression of CD44 isomers that more highly bind high m.w. hyaluronan. At higher concentrations, high m.w. hyaluronan also has direct suppressive effects on T cells. We propose that the state of HA in the matrix environment provides contextual cues to CD4(+)CD25(+) regulatory T cells and T cells, thereby providing a link between the innate inflammatory network and the regulation of adaptive immune responses.

Distinct kinetics in the frequency of peripheral CD4+ T cells in patients with ulcerative colitis experiencing a flare during treatment with mesalazine or with a herbal preparation of myrrh, chamomile, and coffee charcoal.

PubMed

Langhorst, Jost; Frede, Annika; Knott, Markus; Pastille, Eva; Buer, Jan; Dobos, Gustav J; Westendorf, Astrid M

2014-01-01

We found the first evidence of the efficacy of a herbal treatment with myrrh, dry extract of chamomile flowers, and coffee charcoal for ulcerative colitis (UC). However, the impact of the herbal treatment on the CD4+ T-cell compartment, which is essential for both the induction of UC and the maintenance of tolerance in the gut, is not well understood. To analyze the frequency and functional phenotype of CD4+ T cells and of immune-suppressive CD4+CD25high regulatory T cells (Tregs) in healthy control subjects, patients with UC in remission, and patients with clinical flare of UC. Patients in clinical remission were treated with either mesalazine or the herbal preparation for 12 months. The frequencies of whole CD4+ T cells, CD4+CD25med effector T cells, and Tregs and the expression of Foxp3 within the CD4+CD25hig Tregs were determined by flow cytometry at 6 time points. We determined the suppressive capability of Tregs from healthy control subjects and from patients in remission or clinical flare. A total of 79 patients (42 women, 37 men; mean age, 48.5 years; 38 with clinical flare) and 5 healthy control subjects were included in the study. At baseline the frequencies of whole CD4+ T cells, CD4+CD25med effector cells, and Tregs did not differ between the two treatment groups and the healthy control subjects. In addition, patients with UC in sustained clinical remission showed no alteration from baseline after 1, 3, 6, 9, or 12 months of either treatment. In contrast, CD4+ T cells, CD4+CD25med effector T cells, and Tregs demonstrated distinctly different patterns at time points pre-flare and flare. The mesalazine group showed a continuous but not statistically significant increase from baseline to pre-flare and flare (p = ns). In the herbal treatment group, however, the percentage of the CD4+ T cells was lower at pre-flare than at baseline. This decrease was completely reversed after flare, when a significant increase was seen (CD4+CD25med pre-flare/flare p = 0.0461; CD4+CD25high baseline/flare p = 0.0269 and pre-flare/flare p = 0.0032). In contrast, no changes in the expression of Foxp3 cells were detected within the subsets of CD4+CD25high regulatory T cells. Of note, no alterations were detected in the suppressive capability of CD4+CD25high regulatory T cells isolated from the peripheral blood of healthy donors, from patients in remission, or from patients with clinical flare. In patients with UC experiencing acute flare, the CD4+ T compartment demonstrates a distinctly different pattern during treatment with myrrh, chamomile extract, and coffee charcoal than during treatment with mesalazine. These findings suggest an active repopulation of regulatory T cells during active disease. EU Clinical Trials Register 2007-007928-18/DE.

Distinct Kinetics in the Frequency of Peripheral CD4+ T Cells in Patients with Ulcerative Colitis Experiencing a Flare during Treatment with Mesalazine or with a Herbal Preparation of Myrrh, Chamomile, and Coffee Charcoal

PubMed Central

Langhorst, Jost; Frede, Annika; Knott, Markus; Pastille, Eva; Buer, Jan; Dobos, Gustav J.; Westendorf, Astrid M.

2014-01-01

Background We found the first evidence of the efficacy of a herbal treatment with myrrh, dry extract of chamomile flowers, and coffee charcoal for ulcerative colitis (UC). However, the impact of the herbal treatment on the CD4+ T-cell compartment, which is essential for both the induction of UC and the maintenance of tolerance in the gut, is not well understood. Aim To analyze the frequency and functional phenotype of CD4+ T cells and of immune-suppressive CD4+CD25high regulatory T cells (Tregs) in healthy control subjects, patients with UC in remission, and patients with clinical flare of UC. Methods Patients in clinical remission were treated with either mesalazine or the herbal preparation for 12 months. The frequencies of whole CD4+ T cells, CD4+CD25med effector T cells, and Tregs and the expression of Foxp3 within the CD4+CD25hig Tregs were determined by flow cytometry at 6 time points. We determined the suppressive capability of Tregs from healthy control subjects and from patients in remission or clinical flare. Results A total of 79 patients (42 women, 37 men; mean age, 48.5 years; 38 with clinical flare) and 5 healthy control subjects were included in the study. At baseline the frequencies of whole CD4+ T cells, CD4+CD25med effector cells, and Tregs did not differ between the two treatment groups and the healthy control subjects. In addition, patients with UC in sustained clinical remission showed no alteration from baseline after 1, 3, 6, 9, or 12 months of either treatment. In contrast, CD4+ T cells, CD4+CD25medeffector T cells, and Tregs demonstrated distinctly different patterns at time points pre-flare and flare. The mesalazine group showed a continuous but not statistically significant increase from baseline to pre-flare and flare (p = ns). In the herbal treatment group, however, the percentage of the CD4+ T cells was lower at pre-flare than at baseline. This decrease was completely reversed after flare, when a significant increase was seen (CD4+CD25med pre-flare/flare p = 0.0461; CD4+CD25high baseline/flare p = 0.0269 and pre-flare/flare p = 0.0032). In contrast, no changes in the expression of Foxp3 cells were detected within the subsets of CD4+CD25high regulatory T cells. Of note, no alterations were detected in the suppressive capability of CD4+CD25high regulatory T cells isolated from the peripheral blood of healthy donors, from patients in remission, or from patients with clinical flare. Conclusions In patients with UC experiencing acute flare, the CD4+ T compartment demonstrates a distinctly different pattern during treatment with myrrh, chamomile extract, and coffee charcoal than during treatment with mesalazine. These findings suggest an active repopulation of regulatory T cells during active disease. Trial Registration EU Clinical Trials Register 2007-007928-18/DE PMID:25144293

Bone marrow–based homeostatic proliferation of mature T cells in nonhuman primates: implications for AIDS pathogenesis

PubMed Central

Paiardini, Mirko; Cervasi, Barbara; Engram, Jessica C.; Gordon, Shari N.; Klatt, Nichole R.; Muthukumar, Alagarraju; Else, James; Mittler, Robert S.; Staprans, Silvija I.; Sodora, Donald L.

2009-01-01

Bone marrow (BM) is the key hematopoietic organ in mammals and is involved in the homeostatic proliferation of memory CD8+ T cells. Here we expanded on our previous observation that BM is a preferential site for T-cell proliferation in simian immunodeficiency virus (SIV)–infected sooty mangabeys (SMs) that do not progress to AIDS despite high viremia. We found high levels of mature T-cell proliferation, involving both naive and memory cells, in healthy SMs and rhesus macaques (RMs). In addition, we observed in both species that lineage-specific, BM-based T-cell proliferation follows antibody-mediated in vivo CD4+ or CD8+ T-cell depletion, thus indicating a role for the BM in maintaining T-cell homeostasis under depleting circumstances. We also observed that, in SIV-infected SMs, but not RMs, the level of proliferation of BM-based CD4+ T cells is higher than that of circulating CD4+ T cells. Interestingly, limited BM-based CD4+ T-cell proliferation was found in SIV-infected SMs with low CD4+ T-cell counts, suggesting a regenerative failure in these animals. Collectively, these results indicate that BM is involved in maintaining T-cell homeostasis in primates and suggest a role for BM-based CD4+ T-cell proliferation in determining the benign nature of natural SIV infection of SMs. PMID:18832134

Bone marrow-based homeostatic proliferation of mature T cells in nonhuman primates: implications for AIDS pathogenesis.

PubMed

Paiardini, Mirko; Cervasi, Barbara; Engram, Jessica C; Gordon, Shari N; Klatt, Nichole R; Muthukumar, Alagarraju; Else, James; Mittler, Robert S; Staprans, Silvija I; Sodora, Donald L; Silvestri, Guido

2009-01-15

Bone marrow (BM) is the key hematopoietic organ in mammals and is involved in the homeostatic proliferation of memory CD8(+) T cells. Here we expanded on our previous observation that BM is a preferential site for T-cell proliferation in simian immunodeficiency virus (SIV)-infected sooty mangabeys (SMs) that do not progress to AIDS despite high viremia. We found high levels of mature T-cell proliferation, involving both naive and memory cells, in healthy SMs and rhesus macaques (RMs). In addition, we observed in both species that lineage-specific, BM-based T-cell proliferation follows antibody-mediated in vivo CD4(+) or CD8(+) T-cell depletion, thus indicating a role for the BM in maintaining T-cell homeostasis under depleting circumstances. We also observed that, in SIV-infected SMs, but not RMs, the level of proliferation of BM-based CD4(+) T cells is higher than that of circulating CD4(+) T cells. Interestingly, limited BM-based CD4(+) T-cell proliferation was found in SIV-infected SMs with low CD4(+) T-cell counts, suggesting a regenerative failure in these animals. Collectively, these results indicate that BM is involved in maintaining T-cell homeostasis in primates and suggest a role for BM-based CD4(+) T-cell proliferation in determining the benign nature of natural SIV infection of SMs.

The Activation and Inactivation of Mature CD4 T cells: A Case for Peripheral Self–Nonself Discrimination

PubMed Central

Bretscher, P A

2014-01-01

The establishment of central tolerance to most self-antigens results in a repertoire of mature peripheral lymphocytes specific for foreign and peripheral self-antigens. The framework that single, mature lymphocytes are inactivated by antigen, whereas their activation requires lymphocyte cooperation, accounts for diverse observations and incorporates a mechanism of peripheral tolerance. This framework accounts for the generalizations that the sustained activation by antigen of most B cells and CD8 T cells requires CD4 T helper cells; in the absence of CD4 T cells, antigen can inactivate these B cells and CD8 T cells. In this sense, CD4 T cells are the guardians of the fate of most B cells and CD8 T cells when they encounter antigen. I argue here that the single-lymphocyte/multiple-lymphocyte framework for the inactivation/activation of lymphocytes also applies to CD4 T cells. I consider within this framework a model for the activation/inactivation of CD4 T cells that is consistent with the large majority of contemporary observations, including significant clinical observations. I outline the grounds why I feel this model is more plausible than the contemporary and predominant pathogen-associated molecular pattern (PAMP) and Danger Models for CD4 T cell activation. These models are based upon what I consider the radical premise that self–nonself discrimination does not exist at the level of mature CD4 T cells. I explain why I feel this feature renders the PAMP and Danger Models somewhat implausible. The model I propose, in contrast, is conservative in that it embodies such a process of self–nonself discrimination. PMID:24684567

HIV-Infected Children Have Elevated Levels of PD-1+ Memory CD4 T Cells With Low Proliferative Capacity and High Inflammatory Cytokine Effector Functions.

PubMed

Foldi, Julia; Kozhaya, Lina; McCarty, Bret; Mwamzuka, Mussa; Marshed, Fatma; Ilmet, Tiina; Kilberg, Max; Kravietz, Adam; Ahmed, Aabid; Borkowsky, William; Unutmaz, Derya; Khaitan, Alka

2017-09-15

During human immunodeficiency virus (HIV) disease, chronic immune activation leads to T-cell exhaustion. PD-1 identifies "exhausted" CD8 T cells with impaired HIV-specific effector functions, but its role on CD4 T cells and in HIV-infected children is poorly understood. In a Kenyan cohort of vertically HIV-infected children, we measured PD-1+ CD4 T-cell frequencies and phenotype by flow cytometry and their correlation with HIV disease progression and immune activation. Second, in vitro CD4 T-cell proliferative and cytokine responses to HIV-specific and -nonspecific stimuli were assessed with and without PD-1 blockade. HIV-infected children have increased frequencies of PD-1+ memory CD4 T cells that fail to normalize with antiretroviral treatment. These cells are comprised of central and effector memory subsets and correlate with HIV disease progression, measured by viral load, CD4 percentage, CD4:CD8 T-cell ratio, and immune activation. Last, PD-1+ CD4 T cells predict impaired proliferative potential yet preferentially secrete the Th1 and Th17 cytokines interferon-γ and interleukin 17A, and are unresponsive to in vitro PD-1 blockade. This study highlights differences in PD-1+ CD4 T-cell memory phenotype and response to blockade between HIV-infected children and adults, with implications for potential immune checkpoint therapies. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Inhibition of HIV replication by pokeweed antiviral protein targeted to CD4+ cells by monoclonal antibodies

NASA Astrophysics Data System (ADS)

Zarling, Joyce M.; Moran, Patricia A.; Haffar, Omar; Sias, Joan; Richman, Douglas D.; Spina, Celsa A.; Myers, Dorothea E.; Kuebelbeck, Virginia; Ledbetter, Jeffrey A.; Uckun, Fatih M.

1990-09-01

FUNCTIONAL impairment and selective depletion of CD4+ T cells, the hallmark of AIDS, are at least partly caused by human immunodeficiency virus (HIV-1) type 1 binding to the CD4 molecule and infecting CD4+ cells1,2. It may, therefore, be of therapeutic value to target an antiviral agent to CD4+ cells to prevent infection and to inhibit HIV-1 production in patients' CD4+ cells which contain proviral DNA3,4. We report here that HIV-1 replication in normal primary CD4+ T cells can be inhibited by pokeweed antiviral protein, a plant protein of relative molecular mass 30,000 (ref. 5), which inhibits replication of certain plant RNA viruses6-8, and of herpes simplex virus, poliovirus and influenza virus9-11. Targeting pokeweed antiviral protein to CD4+ T cells by conjugating it to monoclonal antibodies reactive with CDS, CD7 or CD4 expressed on CD4+ cells, increased its anti-HIV potency up to 1,000-fold. HIV-1 replication is inhibited at picomolar concentrations of conjugates of pokeweed antiviral protein and monoclonal antibodies, which do not inhibit proliferation of normal CD4+ T cells or CD4-dependent responses. These conjugates inhibit HIV-1 protein synthesis and also strongly inhibit HIV-1 production in activated CD4+ T cells from infected patients.

Induction of cross-priming of naive CD8+ T lymphocytes by recombinant bacillus Calmette-Guerin that secretes heat shock protein 70-major membrane protein-II fusion protein.

PubMed

Mukai, Tetsu; Maeda, Yumi; Tamura, Toshiki; Matsuoka, Masanori; Tsukamoto, Yumiko; Makino, Masahiko

2009-11-15

Because Mycobacterium bovis bacillus Calmette-Guérin (BCG) unconvincingly activates human naive CD8(+) T cells, a rBCG (BCG-70M) that secretes a fusion protein comprising BCG-derived heat shock protein (HSP)70 and Mycobacterium leprae-derived major membrane protein (MMP)-II, one of the immunodominant Ags of M. leprae, was newly constructed to potentiate the ability of activating naive CD8(+) T cells through dendritic cells (DC). BCG-70M secreted HSP70-MMP-II fusion protein in vitro, which stimulated DC to produce IL-12p70 through TLR2. BCG-70M-infected DC activated not only memory and naive CD8(+) T cells, but also CD4(+) T cells of both types to produce IFN-gamma. The activation of these naive T cells by BCG-70M was dependent on the MHC and CD86 molecules on BCG-70M-infected DC, and was significantly inhibited by pretreatment of DC with chloroquine. Both brefeldin A and lactacystin significantly inhibited the activation of naive CD8(+) T cells by BCG-70M through DC. Thus, the CD8(+) T cell activation may be induced by cross-presentation of Ags through a TAP- and proteosome-dependent cytosolic pathway. When naive CD8(+) T cells were stimulated by BCG-70M-infected DC in the presence of naive CD4(+) T cells, CD62L(low)CD8(+) T cells and perforin-producing CD8(+) T cells were efficiently produced. MMP-II-reactive CD4(+) and CD8(+) memory T cells were efficiently produced in C57BL/6 mice by infection with BCG-70M. These results indicate that BCG-70M activated DC, CD4(+) T cells, and CD8(+) T cells, and the combination of HSP70 and MMP-II may be useful for inducing better T cell activation.

Circulating CXCR5+CD4+ T cells participate in the IgE accumulation in allergic asthma.

PubMed

Gong, Fang; Zhu, Hua-Yan; Zhu, Jie; Dong, Qiao-Jing; Huang, Xuan; Jiang, Dong-Jin

2018-05-01

The pathogenesis of allergic asthma is primarily characterized by abnormality in immunoglobin(Ig)E pathway, suggesting a possible role for follicular helper T cells (Tfh) in the genesis of excessive IgE accumulation. The blood chemokine (C-X-C motif) receptor 5 (CXCR)5 + CD4 + T cells, known as "circulating" Tfh, share common functional characteristics with Tfh cells from germinal centers. The aim of this study was to determine the phenotypes and functions of circulating CXCR5 + CD4 + T cells in allergic asthmatics. Here we found the frequency of the circulating CXCR5 + CD4 + T cells was raised in allergic asthma compared with healthy control (HC). Phenotypic assays showed that activated circulating CXCR5 + CD4 + T cells display the key features of Tfh cells, including invariably coexpressed programmed cell death (PD)-1 and inducible costimulator (ICOS). The frequency of interleukin IL-4 + -, IL-21 + -producing CXCR5 + CD4 + T cells was increased in allergic asthma patients compared with HC. Furthermore, sorted circulating CXCR5 + CD4 + T cells from allergic asthma patients boosted IgE production in coculture assay which could be inhibited by IL-4 or IL-21 blockage. Interestingly, IL-4 + -, IL-21 + -CXCR5 + CD4 + T cells positively correlated with total IgE in the blood. Our data indicated that circulating CXCR5 + CD4 + T cells may have a significant role in facilitating IgE production in allergic asthma patients. Copyright © 2018 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

Immunological role of CD4+CD28null T lymphocytes, natural killer cells, and interferon-gamma in pediatric patients with sickle cell disease: relation to disease severity and response to therapy.

PubMed

ElAlfy, Mohsen Saleh; Adly, Amira Abdel Moneam; Ebeid, Fatma Soliman ElSayed; Eissa, Deena Samir; Ismail, Eman Abdel Rahman; Mohammed, Yasser Hassan; Ahmed, Manar Elsayed; Saad, Aya Sayed

2018-06-20

Sickle cell disease (SCD) is associated with alterations in immune phenotypes. CD4 + CD28 null T lymphocytes have pro-inflammatory functions and are linked to vascular diseases. To assess the percentage of CD4 + CD28 null T lymphocytes, natural killer cells (NK), and IFN-gamma levels, we compared 40 children and adolescents with SCD with 40 healthy controls and evaluated their relation to disease severity and response to therapy. Patients with SCD steady state were studied, focusing on history of frequent vaso-occlusive crisis, hydroxyurea therapy, and IFN-gamma levels. Analysis of CD4 + CD28 null T lymphocytes and NK cells was done by flow cytometry. Liver and cardiac iron overload were assessed. CD4 + CD28 null T lymphocytes, NK cells, and IFN-gamma levels were significantly higher in patients than controls. Patients with history of frequent vaso-occlusive crisis and those with vascular complications had higher percentage of CD4 + CD28 null T lymphocytes and IFN-gamma while levels were significantly lower among hydroxyurea-treated patients. CD4 + CD28 null T lymphocytes were positively correlated to transfusional iron input while these cells and IFN-gamma were negatively correlated to cardiac T2* and duration of hydroxyurea therapy. NK cells were correlated to HbS and indirect bilirubin. Increased expression of CD4 + CD28 null T lymphocytes highlights their role in immune dysfunction and pathophysiology of SCD complications.

Evaluation of the impact of chitosan/DNA nanoparticles on the differentiation of human naive CD4+ T cells

NASA Astrophysics Data System (ADS)

Liu, Lanxia; Bai, Yuanyuan; Zhu, Dunwan; Song, Liping; Wang, Hai; Dong, Xia; Zhang, Hailing; Leng, Xigang

2011-06-01

Chitosan (CS) is one of the most widely studied polymers in non-viral gene delivery since it is a cationic polysaccharide that forms nanoparticles with DNA and hence protects the DNA against digestion by DNase. However, the impact of CS/DNA nanoparticle on the immune system still remains poorly understood. Previous investigations did not found CS/DNA nanoparticles had any significant impact on the function of human and murine macrophages. To date, little is known about the interaction between CS/DNA nanoparticles and naive CD4+ T cells. This study was designed to investigate whether CS/DNA nanoparticles affect the initial differentiation direction of human naive CD4+ T cells. The indirect impact of CS/DNA nanoparticles on naive CD4+ T cell differentiation was investigated by incubating the nanoparticles with human macrophage THP-1 cells in one chamber of a transwell co-incubation system, with the enriched human naive CD4+ T cells being placed in the other chamber of the transwell. The nanoparticles were also co-incubated with the naive CD4+ T cells to explore their direct impact on naive CD4+ T cell differentiation by measuring the release of IL-4 and IFN-γ from the cells. It was demonstrated that CS/DNA nanoparticles induced slightly elevated production of IL-12 by THP-1 cells, possibly owing to the presence of CpG motifs in the plasmid. However, this macrophage stimulating activity was much less significant as compared with lipopolysaccharide and did not impact on the differentiation of the naive CD4+ T cells. It was also demonstrated that, when directly exposed to the naive CD4+ T cells, the nanoparticles induced neither the activation of the naive CD4+ T cells in the absence of recombinant cytokines (recombinant human IL-4 or IFN-γ) that induce naive CD4+ T cell polarization, nor any changes in the differentiation direction of naive CD4+ T cells in the presence of the corresponding cytokines.

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

PubMed

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

2018-05-15

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

Clinical significance of Tim3-positive T cell subsets in patients with multiple sclerosis.

PubMed

Feng, Xuemei; Feng, Juan

2016-12-01

The present study evaluated associations between the percentages of T cell immunoglobulin and mucin domain 3 (Tim3)-positive T cells and related cytokines and multiple sclerosis (MS). We collected peripheral blood samples from 30 MS patients and 30 healthy controls. Flow cytometry was used to determine the proportions of CD3 + Tim3 + , CD4 + Tim3 + , and CD4 + CD25 + Tim3 + in peripheral blood mononuclear cells (PBMCs) and related cell subsets. The serum concentrations of galectin-9, IL-17, and IFN-γ also were determined using enzyme-linked immunosorbent assays (ELISA). The percentages of Tim3-positive T cells in CD4 + and CD4 + CD25 + T cell subsets were significantly lower among MS patients than among controls. This difference was particularly evident in the CD4 + CD25(high) T cell subset. The proportions of CD4 + Tim3 + and CD4 + CD25 + Tim3 + cells in PBMCs were significantly lower in the MS group than in the control group, whereas no significant differences were detected regarding the percentages of CD3 + Tim3 + in PBMCs and T cell subsets. The serum concentrations of galectin-9, IL-17, and IFN-γ all were increased in MS patients compared with healthy controls. Our results support that Tim3 and related cytokines may be involved in the onset of MS. Copyright © 2016 Elsevier Ltd. All rights reserved.

Chronic exposure to water pollutant trichloroethylene increased epigenetic drift in CD4+ T cells

PubMed Central

Gilbert, Kathleen M; Blossom, Sarah J; Erickson, Stephen W; Reisfeld, Brad; Zurlinden, Todd J; Broadfoot, Brannon; West, Kirk; Bai, Shasha; Cooney, Craig A

2016-01-01

Aim: Autoimmune disease and CD4+ T-cell alterations are induced in mice exposed to the water pollutant trichloroethylene (TCE). We examined here whether TCE altered gene-specific DNA methylation in CD4+ T cells as a possible mechanism of immunotoxicity. Materials & methods: Naive and effector/memory CD4+ T cells from mice exposed to TCE (0.5 mg/ml in drinking water) for 40 weeks were examined by bisulfite next-generation DNA sequencing. Results: A probabilistic model calculated from multiple genes showed that TCE decreased methylation control in CD4+ T cells. Data from individual genes fitted to a quadratic regression model showed that TCE increased gene-specific methylation variance in both CD4 subsets. Conclusion: TCE increased epigenetic drift of specific CpG sites in CD4+ T cells. PMID:27092578

IL-7 promotes long-term in vitro survival of unique long-lived memory subset generated from mucosal effector memory CD4+ T cells in chronic colitis mice.

PubMed

Takahara, Masahiro; Nemoto, Yasuhiro; Oshima, Shigeru; Matsuzawa, Yu; Kanai, Takanori; Okamoto, Ryuichi; Tsuchiya, Kiichiro; Nakamura, Tetsuya; Yamamoto, Kazuhide; Watanabe, Mamoru

2013-01-01

Colitogenic memory CD4(+) T cells are important in the pathogenesis of inflammatory bowel disease (IBD). Although memory stem cells with high survival and self-renewal capacity were recently identified in both mice and humans, it is unclear whether a similar subset is present in chronic colitis mice. We sought to identify and purify a long-lived subset of colitogenic memory CD4(+) T cells, which may be targets for treatment of IBD. A long-lived subset of colitogenic memory CD4(+) T cells was purified using a long-term culture system. The characteristics of these cells were assessed. Interleukin (IL)-7 promoted the in vitro survival for >8 weeks of lamina propria (LP) CD4(+) T cells from colitic SCID mice previously injected with CD4(+)CD45RB(high) T cells. These cells were in a quiescent state and divided a maximum of 5 times in 4 weeks. LP CD4(+) T cells expressed higher levels of Bcl-2, integrin-α4β7, CXCR3 and CD25 after than before culture, as well as secreting high concentrations of IL-2 and low concentrations of IFN-γ and IL-17 in response to intestinal bacterial antigens. LP CD4(+) T cells from colitic mice cultured with IL-7 for 8 weeks induced more severe colitis than LP CD4(+) T cells cultured for 4 weeks. We developed a novel culture system to purify a long-lived, highly pathogenic memory subset from activated LP CD4(+) T cells. IL-7 promoted long-term in vitro survival of this subset in a quiescent state. This subset will be a novel, effective target for the treatment of IBD. Copyright © 2013 Elsevier B.V. All rights reserved.

Increased Numbers of CD4+CD25+ and CD8+CD25+ T-Cells in Peripheral Blood of Patients with Rheumatoid Arthritis with Parvovirus B19 Infection.

PubMed

Naciute, Milda; Maciunaite, Gabriele; Mieliauskaite, Diana; Rugiene, Rita; Zinkeviciene, Aukse; Mauricas, Mykolas; Murovska, Modra; Girkontaite, Irute

2017-01-01

To investigate T-cell subpopulations in peripheral blood of human parvovirus B19 DNA-positive (B19 + ) and -negative (B19 - ) patients with rheumatoid arthritis (RA) and healthy persons. Blood samples were collected from 115 patients with RA and 47 healthy volunteers; 27 patients with RA and nine controls were B19 + Cluster of differentiation (CD) 4, 8, 25 and 45RA were analyzed on blood cells. CD25 expression on CD4 + CD45RA + , CD4 + CD45RA - , CD8 + CD45RA + , CD8 + CD45RA - subsets were analyzed by flow cytometry. The percentage of CD25 low and CD25 hi cells was increased on CD4 + CD45RA + , CD4 + CD45RA - T-cells and the percentage of CD25 + cells was increased on CD8 + CD45RA + , CD8 + CD45RA - T-cells of B19 + patients with RA in comparison with B19 - patients and controls. Raised levels of CD4 and CD8 regulatory T-cells in B19 + RA patients could cause down-regulation of antiviral clearance mechanisms and lead to activation of persistent human parvovirus B19 infection in patients with RA. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Increased Numbers of CD4+CD25+ and CD8+CD25+ T-Cells in Peripheral Blood of Patients with Rheumatoid Arthritis with Parvovirus B19 Infection

PubMed Central

NACIUTE, MILDA; MACIUNAITE, GABRIELE; MIELIAUSKAITE, DIANA; RUGIENE, RITA; ZINKEVICIENE, AUKSE; MAURICAS, MYKOLAS; MUROVSKA, MODRA; GIRKONTAITE, IRUTE

2017-01-01

Aim: To investigate T-cell subpopulations in peripheral blood of human parvovirus B19 DNA-positive (B19+) and -negative (B19−) patients with rheumatoid arthritis (RA) and healthy persons. Patients and Methods: Blood samples were collected from 115 patients with RA and 47 healthy volunteers; 27 patients with RA and nine controls were B19+. Cluster of differentiation (CD) 4, 8, 25 and 45RA were analyzed on blood cells. CD25 expression on CD4+CD45RA+, CD4+CD45RA−, CD8+CD45RA+, CD8+CD45RA− subsets were analyzed by flow cytometry. Results: The percentage of CD25low and CD25hi cells was increased on CD4+CD45RA+, CD4+CD45RA− T-cells and the percentage of CD25+ cells was increased on CD8+CD45RA+, CD8+CD45RA− T-cells of B19+ patients with RA in comparison with B19− patients and controls. Conclusion: Raised levels of CD4 and CD8 regulatory T-cells in B19+ RA patients could cause down-regulation of antiviral clearance mechanisms and lead to activation of persistent human parvovirus B19 infection in patients with RA PMID:28358698

Peripheral CD4+ naïve/memory ratio is an independent predictor of survival in non-small cell lung cancer

PubMed Central

Yang, Peng; Ma, Junhong; Yang, Xin; Li, Wei

2017-01-01

Background To investigate the clinical significance of naïve T cells, memory T cells, CD45RA+CD45RO+ T cells, and naïve/memory ratio in non-small cell lung cancer (NSCLC) patients. Methods Pretreatment peripheral blood samples from 76 NSCLC patients and 28 age- and sex-matched healthy volunteers were collected and tested for immune cells by flow cytometry. We compared the expression of these immune cells between patients and healthy controls and evaluated their predictive roles for survival in NSCLC by cox proportional hazards model. Results Decreased naïve CD4+ T cells, naïve CD8+ T cells, CD4+ naïve/memory ratios and CD4+CD45RA+CD45RO+ T cells, and increased memory CD4+ T cells, were observed in 76 NSCLC patients compared to healthy volunteers. Univariate analysis revealed that elevated CD4+ naïve/memory ratio correlated with prolonged progression-free survival (P=0.013). Multivariate analysis confirmed its predictive role with a hazard ratio of 0.35 (95% confidence interval, 0.19-0.75, P=0.012). Conclusions Peripheral CD4+ naïve/memory ratio can be used as a predictive biomarker in NSCLC patients and used to optimize personalized treatment strategies. PMID:29137371

Modulation of Endoplasmic Reticulum Stress Controls CD4+ T-cell Activation and Antitumor Function.

PubMed

Thaxton, Jessica E; Wallace, Caroline; Riesenberg, Brian; Zhang, Yongliang; Paulos, Chrystal M; Beeson, Craig C; Liu, Bei; Li, Zihai

2017-08-01

The endoplasmic reticulum (ER) is an energy-sensing organelle with intimate ties to programming cell activation and metabolic fate. T-cell receptor (TCR) activation represents a form of acute cell stress and induces mobilization of ER Ca 2+ stores. The role of the ER in programming T-cell activation and metabolic fate remains largely undefined. Gp96 is an ER protein with functions as a molecular chaperone and Ca 2+ buffering protein. We hypothesized that the ER stress response may be important for CD4 + T-cell activation and that gp96 may be integral to this process. To test our hypothesis, we utilized genetic deletion of the gp96 gene Hsp90b1 in a CD4 + T cell-specific manner. We show that gp96-deficient CD4 + T cells cannot undergo activation-induced glycolysis due to defective Ca 2+ mobilization upon TCR engagement. We found that activating naïve CD4 + T cells while inhibiting ER Ca 2+ exchange, through pharmacological blockade of the ER Ca 2+ channel inositol trisphosphate receptor (IP 3 R), led to a reduction in cytosolic Ca 2+ content and generated a pool of CD62L high /CD44 low CD4 + T cells compared with wild-type (WT) matched controls. In vivo IP 3 R-inhibited CD4 + T cells exhibited elevated tumor control above WT T cells. Together, these data show that ER-modulated cytosolic Ca 2+ plays a role in defining CD4 + T-cell phenotype and function. Factors associated with the ER stress response are suitable targets for T cell-based immunotherapies. Cancer Immunol Res; 5(8); 666-75. ©2017 AACR . ©2017 American Association for Cancer Research.

Role of IL-4 receptor α-positive CD4(+) T cells in chronic airway hyperresponsiveness.

PubMed

Kirstein, Frank; Nieuwenhuizen, Natalie E; Jayakumar, Jaisubash; Horsnell, William G C; Brombacher, Frank

2016-06-01

TH2 cells and their cytokines are associated with allergic asthma in human subjects and with mouse models of allergic airway disease. IL-4 signaling through the IL-4 receptor α (IL-4Rα) chain on CD4(+) T cells leads to TH2 cell differentiation in vitro, implying that IL-4Rα-responsive CD4(+) T cells are critical for the induction of allergic asthma. However, mechanisms regulating acute and chronic allergen-specific TH2 responses in vivo remain incompletely understood. This study defines the requirements for IL-4Rα-responsive CD4(+) T cells and the IL-4Rα ligands IL-4 and IL-13 in the development of allergen-specific TH2 responses during the onset and chronic phase of experimental allergic airway disease. Development of acute and chronic ovalbumin (OVA)-induced allergic asthma was assessed weekly in CD4(+) T cell-specific IL-4Rα-deficient BALB/c mice (Lck(cre)IL-4Rα(-/lox)) and respective control mice in the presence or absence of IL-4 or IL-13. During acute allergic airway disease, IL-4 deficiency did not prevent the onset of TH2 immune responses and OVA-induced airway hyperresponsiveness or goblet cell hyperplasia, irrespective of the presence or absence of IL-4Rα-responsive CD4(+) T cells. In contrast, deficiency of IL-13 prevented allergic asthma, irrespective of the presence or absence of IL-4Rα-responsive CD4(+) T cells. Importantly, chronic allergic inflammation and airway hyperresponsiveness were dependent on IL-4Rα-responsive CD4(+) T cells. Deficiency in IL-4Rα-responsive CD4(+) T cells resulted in increased numbers of IL-17-producing T cells and, consequently, increased airway neutrophilia. IL-4-responsive T helper cells are dispensable for acute OVA-induced airway disease but crucial in maintaining chronic asthmatic pathology. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Memory CD4+ T cells: beyond “helper” functions

PubMed Central

Boonnak, Kobporn; Subbarao, Kanta

2012-01-01

In influenza virus infection, antibodies, memory CD8+ T cells, and CD4+ T cells have all been shown to mediate immune protection, but how they operate and interact with one another to mediate efficient immune responses against virus infection is not well understood. In this issue of the JCI, McKinstry et al. have identified unique functions of memory CD4+ T cells beyond providing “help” for B cell and CD8+ T cell responses during influenza virus infection. PMID:22820285

Increased autophagy in CD4+ T cells of rheumatoid arthritis patients results in T-cell hyperactivation and apoptosis resistance.

PubMed

van Loosdregt, Jorg; Rossetti, Maura; Spreafico, Roberto; Moshref, Maryam; Olmer, Merissa; Williams, Gary W; Kumar, Pavanish; Copeland, Dana; Pischel, Ken; Lotz, Martin; Albani, Salvatore

2016-12-01

Rheumatoid arthritis (RA) is an autoimmune disease hallmarked by aberrant cellular homeostasis, resulting in hyperactive CD4 + T cells that are more resistant to apoptosis. Both hyperactivation and resistance to apoptosis may contribute to the pathogenicity of CD4 + T cells in the autoimmune process. A better knowledge of the mechanisms determining such impaired homeostasis could contribute significantly to both the understanding and the treatment of the disease. Here we investigated whether autophagy, is dysregulated in CD4 + T cells of RA patients, resulting in disturbed T-cell homeostasis. We demonstrate that the rate of autophagy is significantly increased in CD4 + T cells from RA patients, and that increased autophagy is also a feature of in vitro activated CD4 + T cells. The increased apoptosis resistance observed in CD4 + T cells from RA patients was significantly reversed upon autophagy inhibition. These mechanisms may contribute to RA pathogenesis, as autophagy inhibition reduced both arthritis incidence and disease severity in a mouse collagen induced arthritis mouse model. Conversely, in Atg5 flox/flox -CD4-Cre + mice, in which all T cells are autophagy deficient, T cells showed impaired activation and proliferation. These data provide novel insight into the pathogenesis of RA and underscore the relevance of autophagy as a promising therapeutic target. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Central memory CD4 T cells are associated with incomplete restoration of the CD4 T cell pool after treatment-induced long-term undetectable HIV viraemia.

PubMed

Rallón, Norma; Sempere-Ortells, José M; Soriano, Vincent; Benito, José M

2013-11-01

It is unclear to what extent T cell reconstitution may be possible in HIV-1-infected individuals on continuous successful highly active antiretroviral therapy (HAART). Herein, we analysed distinct phenotypic markers of immune recovery in patients with undetectable viraemia for 8 years, taking as reference untreated patients and healthy controls. Seventy-two subjects were examined: 28 HIV-1+ patients on successful long-term HAART, 24 HIV-1+ untreated viraemic patients and 20 age-matched healthy controls. Analysis of naive and memory CD4 and CD8 T cells was combined with measurements of activation status (expression of CD38) and with thymic function (expression of CD31). Statistical significance was determined by non-parametric tests. After long-term HAART, the majority of parameters were normalized compared with age-matched control values, including T cell activation and thymic function. However, absolute counts of naive and central memory CD4 T cells remained below normal levels. The only parameters significantly associated with CD4 counts at the end of follow-up were the pre-HAART CD4 count ( β ± SD = 0.54 ± 0.16, P = 0.003) and the level of CD4 central memory cells at the end of follow-up (β ± SD = 1.18 ± 0.23, P < 0.0001). Only patients starting HAART with CD4 counts >350 cells/mm(3) reached a complete normalization of CD4 counts. Even after long-term successful HAART, complete CD4 restoration may be attainable only in patients starting therapy with moderately high CD4 counts, prompting early initiation of antiretroviral therapy. Incomplete CD4 restoration may be associated with a defective restoration of central memory CD4 T cells, a cell subset with a pivotal role in T cell homeostasis.

STAT3 signaling in CD4+ T cells is critical for the pathogenesis of chronic sclerodermatous graft-versus-host disease in a murine model.

PubMed

Radojcic, Vedran; Pletneva, Maria A; Yen, Hung-Rong; Ivcevic, Sanja; Panoskaltsis-Mortari, Angela; Gilliam, Anita C; Drake, Charles G; Blazar, Bruce R; Luznik, Leo

2010-01-15

Donor CD4+ T cells are thought to be essential for inducing delayed host tissue injury in chronic graft-versus-host disease (GVHD). However, the relative contributions of distinct effector CD4+ T cell subpopulations and the molecular pathways influencing their generation are not known. We investigated the role of the STAT3 pathway in a murine model of chronic sclerodermatous GVHD. This pathway integrates multiple signaling events during the differentiation of naive CD4+ T cells and impacts their homeostasis. We report that chimeras receiving an allograft containing STAT3-ablated donor CD4+ T cells do not develop classic clinical and pathological manifestations of alloimmune tissue injury. Analysis of chimeras showed that abrogation of STAT3 signaling reduced the in vivo expansion of donor-derived CD4+ T cells and their accumulation in GVHD target tissues without abolishing antihost alloreactivity. STAT3 ablation did not significantly affect Th1 differentiation while enhancing CD4+CD25+Foxp3+ T cell reconstitution through thymus-dependent and -independent pathways. Transient depletion of CD25+ T cells in chimeras receiving STAT3-deficient T cells resulted in delayed development of alloimmune gut and liver injury. This delayed de novo GVHD was associated with the emergence of donor hematopoietic stem cell-derived Th1 and Th17 cells. These results suggest that STAT3 signaling in graft CD4+ T cells links the alloimmune tissue injury of donor graft T cells and the emergence of donor hematopoietic stem cell-derived pathogenic effector cells and that both populations contribute, albeit in different ways, to the genesis of chronic GVHD after allogenic bone marrow transplantation in a murine model.

Genetics Home Reference: ZAP70-related severe combined immunodeficiency

MedlinePlus

... involved in the activation of helper T cells (CD4+ T cells). These cells direct and assist the functions of ... CD8+ T cells and an excess of inactive CD4+ T cells. The resulting shortage of active T cells causes ...

Ex Vivo Restimulation of Human PBMC Expands a CD3+CD4−CD8− γδ + T Cell Population That Can Confound the Evaluation of CD4 and CD8 T Cell Responses to Vaccination

PubMed Central

Sedgmen, B. J.; Papalia, L.; Wang, L.; Dyson, A. R.; McCallum, H. A.; Simson, C. M.; Pearse, M. J.; Maraskovsky, E.; Hung, D.; Eomois, P. P.; Hartel, G.; Barnden, M. J.; Rockman, S. P.

2013-01-01

The measurement of vaccine-induced humoral and CD4+ and CD8+ cellular immune responses represents an important correlate of vaccine efficacy. Accurate and reliable assays evaluating such responses are therefore critical during the clinical development phase of vaccines. T cells play a pivotal role both in coordinating the adaptive and innate immune responses and as effectors. During the assessment of cell-mediated immunity (CMI) in subjects participating in a large-scale influenza vaccine trial, we identified the expansion of an IFN-γ-producing CD3+CD4−CD8− γδ + T cell population in the peripheral blood of 90/610 (15%) healthy subjects. The appearance of CD3+CD4−CD8− γδ + T cells in the blood of subjects was transient and found to be independent of the study cohort, vaccine group, subject gender and ethnicity, and ex vivo restimulation conditions. Although the function of this population and relevance to vaccination are unclear, their inclusion in the total vaccine-specific T-cell response has the potential to confound data interpretation. It is thus recommended that when evaluating the induction of IFN-γ-producing CD4+ and CD8+ immune responses following vaccination, the CD3+CD4−CD8− γδ + T cells are either excluded or separately enumerated from the overall frequency determination. PMID:24066003

ICOS and Bcl6-dependent pathways maintain a CD4 T cell population with memory-like properties during tuberculosis.

PubMed

Moguche, Albanus O; Shafiani, Shahin; Clemons, Corey; Larson, Ryan P; Dinh, Crystal; Higdon, Lauren E; Cambier, C J; Sissons, James R; Gallegos, Alena M; Fink, Pamela J; Urdahl, Kevin B

2015-05-04

Immune control of persistent infection with Mycobacterium tuberculosis (Mtb) requires a sustained pathogen-specific CD4 T cell response; however, the molecular pathways governing the generation and maintenance of Mtb protective CD4 T cells are poorly understood. Using MHCII tetramers, we show that Mtb-specific CD4 T cells are subject to ongoing antigenic stimulation. Despite this chronic stimulation, a subset of PD-1(+) cells is maintained within the lung parenchyma during tuberculosis (TB). When transferred into uninfected animals, these cells persist, mount a robust recall response, and provide superior protection to Mtb rechallenge when compared to terminally differentiated Th1 cells that reside preferentially in the lung-associated vasculature. The PD-1(+) cells share features with memory CD4 T cells in that their generation and maintenance requires intrinsic Bcl6 and intrinsic ICOS expression. Thus, the molecular pathways required to maintain Mtb-specific CD4 T cells during ongoing infection are similar to those that maintain memory CD4 T cells in scenarios of antigen deprivation. These results suggest that vaccination strategies targeting the ICOS and Bcl6 pathways in CD4 T cells may provide new avenues to prevent TB. © 2015 Moguche et al.

Endothelial Cell Stimulation Overcomes Restriction and Promotes Productive and Latent HIV-1 Infection of Resting CD4+ T Cells

PubMed Central

Baker, Jacob J.; Scott, Geoffrey L.; Davis, Yelena P.; Ho, Yen-Yi; Siliciano, Robert F.

2013-01-01

Highly active antiretroviral therapy (HAART) is able to suppress human immunodeficiency virus type 1 (HIV-1) to undetectable levels in the majority of patients, but eradication has not been achieved because latent viral reservoirs persist, particularly in resting CD4+ T lymphocytes. It is generally understood that HIV-1 does not efficiently infect resting CD4+ T cells, and latent infection in those cells may arise when infected CD4+ T lymphoblasts return to resting state. In this study, we found that stimulation by endothelial cells can render resting CD4+ T cells permissible for direct HIV infection, including both productive and latent infection. These stimulated T cells remain largely phenotypically unactivated and show a lower death rate than activated T cells, which promotes the survival of infected cells. The stimulation by endothelial cells does not involve interleukin 7 (IL-7), IL-15, CCL19, or CCL21. Endothelial cells line the lymphatic vessels in the lymphoid tissues and have frequent interactions with T cells in vivo. Our study proposes a new mechanism for infection of resting CD4+ T cells in vivo and a new mechanism for latent infection in resting CD4+ T cells. PMID:23824795

A novel differentiation pathway from CD4+ T cells to CD4− T cells for maintaining immune system homeostasis

PubMed Central

Zhao, X; Sun, G; Sun, X; Tian, D; Liu, K; Liu, T; Cong, M; Xu, H; Li, X; Shi, W; Tian, Y; Yao, J; Guo, H; Zhang, D

2016-01-01

CD4+ T lymphocytes are key players in the adaptive immune system and can differentiate into a variety of effector and regulatory T cells. Here, we provide evidence that a novel differentiation pathway of CD4+ T cells shifts the balance from a destructive T-cell response to one that favors regulation in an immune-mediated liver injury model. Peripheral CD4−CD8−NK1.1− double-negative T cells (DNT) was increased following Concanavalin A administration in mice. Adoptive transfer of DNT led to significant protection from hepatocyte necrosis by direct inhibition on the activation of lymphocytes, a process that occurred primarily through the perforin-granzyme B route. These DNT converted from CD4+ rather than CD8+ T cells, a process primarily regulated by OX40. DNT migrated to the liver through the CXCR3-CXCL9/CXCL10 interaction. In conclusion, we elucidated a novel differentiation pathway from activated CD4+ T cells to regulatory DNT cells for maintaining homeostasis of the immune system in vivo, and provided key evidence that utilizing this novel differentiation pathway has potential application in the prevention and treatment of autoimmune diseases. PMID:27077809

Innovative Strategies for Breast Cancer Immunotherapy

DTIC Science & Technology

2014-09-01

donors, percentages of CD4+ and CD8+ T cells as well as T regulatory cells ( Tregs : FOXP3 and CD25 positive) were determined in K-CAR T cells...obtained from BC patients or normal female donors, since Tregs are a component of the immune system that suppresses immune responses of other cells. A...immunosuppressive mechanisms that inhibit T cell activation (33). Suppression of CD8+ effector cells by CD4+CD25+FoxP3+ regulatory T cells ( Tregs ) plays a key role

Cytomegalovirus (CMV) Epitope-Specific CD4+ T Cells Are Inflated in HIV+ CMV+ Subjects.

PubMed

Abana, Chike O; Pilkinton, Mark A; Gaudieri, Silvana; Chopra, Abha; McDonnell, Wyatt J; Wanjalla, Celestine; Barnett, Louise; Gangula, Rama; Hager, Cindy; Jung, Dae K; Engelhardt, Brian G; Jagasia, Madan H; Klenerman, Paul; Phillips, Elizabeth J; Koelle, David M; Kalams, Spyros A; Mallal, Simon A

2017-11-01

Select CMV epitopes drive life-long CD8 + T cell memory inflation, but the extent of CD4 memory inflation is poorly studied. CD4 + T cells specific for human CMV (HCMV) are elevated in HIV + HCMV + subjects. To determine whether HCMV epitope-specific CD4 + T cell memory inflation occurs during HIV infection, we used HLA-DR7 (DRB1*07:01) tetramers loaded with the glycoprotein B DYSNTHSTRYV (DYS) epitope to characterize circulating CD4 + T cells in coinfected HLA-DR7 + long-term nonprogressor HIV subjects with undetectable HCMV plasma viremia. DYS-specific CD4 + T cells were inflated among these HIV + subjects compared with those from an HIV - HCMV + HLA-DR7 + cohort or with HLA-DR7-restricted CD4 + T cells from the HIV-coinfected cohort that were specific for epitopes of HCMV phosphoprotein-65, tetanus toxoid precursor, EBV nuclear Ag 2, or HIV gag protein. Inflated DYS-specific CD4 + T cells consisted of effector memory or effector memory-RA + subsets with restricted TCRβ usage and nearly monoclonal CDR3 containing novel conserved amino acids. Expression of this near-monoclonal TCR in a Jurkat cell-transfection system validated fine DYS specificity. Inflated cells were polyfunctional, not senescent, and displayed high ex vivo levels of granzyme B, CX 3 CR1, CD38, or HLA-DR but less often coexpressed CD38 + and HLA-DR + The inflation mechanism did not involve apoptosis suppression, increased proliferation, or HIV gag cross-reactivity. Instead, the findings suggest that intermittent or chronic expression of epitopes, such as DYS, drive inflation of activated CD4 + T cells that home to endothelial cells and have the potential to mediate cytotoxicity and vascular disease. Copyright © 2017 by The American Association of Immunologists, Inc.

Defects of mitogen-activated protein kinase in ICOS signaling pathway lead to CD4(+) and CD8(+) T-cell dysfunction in patients with active SLE.

PubMed

Gang, Cai; Jiahui, Yang; Huaizhou, Wang; Qing, Cai; Dongbao, Zhao; Qian, Shen

2009-01-01

In this study, hypoproliferation and defects of effectors and cytokines in CD4(+) and CD8(+) T-cells via ICOS costimulation were found in active SLE patients, relative to normal individuals and RA patient controls. Exogenous IL-2 can partially reverse those defects. In addition, low level of ERK phosphorylation in ICOS-mediated signaling pathway was discovered in lupus CD4(+) and CD8(+) T-cells. When blocked with ERK-specific chemical inhibitor PD98059, cell proliferation and IL-2 production via ICOS costimulation from both CD4(+) and CD8(+) T-cells will be severely inhibited. These findings confirmed the dysfunction of both CD4(+) and CD8(+) T-cells after ICOS costimulation in lupus patients and most importantly pointed out that impairment of ERK activation might be one of the critical factors involved in ICOS-mediated IL-2 and T-cell hypoproliferation in active SLE.

Mtb-specific CD27low CD4 T cells as markers of lung tissue destruction during pulmonary tuberculosis in humans.

PubMed

Nikitina, Irina Yu; Kondratuk, Natalya A; Kosmiadi, George A; Amansahedov, Rasul B; Vasilyeva, Irina A; Ganusov, Vitaly V; Lyadova, Irina V

2012-01-01

Effector CD4 T cells represent a key component of the host's anti-tuberculosis immune defense. Successful differentiation and functioning of effector lymphocytes protects the host against severe M. tuberculosis (Mtb) infection. On the other hand, effector T cell differentiation depends on disease severity/activity, as T cell responses are driven by antigenic and inflammatory stimuli released during infection. Thus, tuberculosis (TB) progression and the degree of effector CD4 T cell differentiation are interrelated, but the relationships are complex and not well understood. We have analyzed an association between the degree of Mtb-specific CD4 T cell differentiation and severity/activity of pulmonary TB infection. The degree of CD4 T cell differentiation was assessed by measuring the percentages of highly differentiated CD27(low) cells within a population of Mtb- specific CD4 T lymphocytes ("CD27(low)IFN-γ(+)" cells). The percentages of CD27(low)IFN-γ+ cells were low in healthy donors (median, 33.1%) and TB contacts (21.8%) but increased in TB patients (47.3%, p<0.0005). Within the group of patients, the percentages of CD27(low)IFN-γ(+) cells were uniformly high in the lungs (>76%), but varied in blood (12-92%). The major correlate for the accumulation of CD27(low)IFN-γ(+) cells in blood was lung destruction (r = 0.65, p = 2.7 × 10(-7)). A cutoff of 47% of CD27(low)IFN-γ(+) cells discriminated patients with high and low degree of lung destruction (sensitivity 89%, specificity 74%); a decline in CD27(low)IFN-γ(+)cells following TB therapy correlated with repair and/or reduction of lung destruction (p<0.01). Highly differentiated CD27(low) Mtb-specific (CD27(low)IFN-γ(+)) CD4 T cells accumulate in the lungs and circulate in the blood of patients with active pulmonary TB. Accumulation of CD27(low)IFN-γ(+) cells in the blood is associated with lung destruction. The findings indicate that there is no deficiency in CD4 T cell differentiation during TB; evaluation of CD27(low)IFN-γ(+) cells provides a valuable means to assess TB activity, lung destruction, and tissue repair following TB therapy.

Acute Malaria Induces PD1+CTLA4+ Effector T Cells with Cell-Extrinsic Suppressor Function

PubMed Central

Mackroth, Maria Sophia; Abel, Annemieke; Steeg, Christiane; Schulze zur Wiesch, Julian; Jacobs, Thomas

2016-01-01

In acute Plasmodium falciparum (P. falciparum) malaria, the pro- and anti-inflammatory immune pathways must be delicately balanced so that the parasitemia is controlled without inducing immunopathology. An important mechanism to fine-tune T cell responses in the periphery is the induction of coinhibitory receptors such as CTLA4 and PD1. However, their role in acute infections such as P. falciparum malaria remains poorly understood. To test whether coinhibitory receptors modulate CD4+ T cell functions in malaria, blood samples were obtained from patients with acute P. falciparum malaria treated in Germany. Flow cytometric analysis showed a more frequent expression of CTLA4 and PD1 on CD4+ T cells of malaria patients than of healthy control subjects. In vitro stimulation with P. falciparum-infected red blood cells revealed a distinct population of PD1+CTLA4+CD4+ T cells that simultaneously produced IFNγ and IL10. This antigen-specific cytokine production was enhanced by blocking PD1/PDL1 and CTLA4. PD1+CTLA4+CD4+ T cells were further isolated based on surface expression of PD1 and their inhibitory function investigated in-vitro. Isolated PD1+CTLA4+CD4+ T cells suppressed the proliferation of the total CD4+ population in response to anti-CD3/28 and plasmodial antigens in a cell-extrinsic manner. The response to other specific antigens was not suppressed. Thus, acute P. falciparum malaria induces P. falciparum-specific PD1+CTLA4+CD4+ Teffector cells that coproduce IFNγ and IL10, and inhibit other CD4+ T cells. Transient induction of regulatory Teffector cells may be an important mechanism that controls T cell responses and might prevent severe inflammation in patients with malaria and potentially other acute infections. PMID:27802341

MTOR ACTIVATION TRIGGERS IL-4 PRODUCTION AND NECROTIC DEATH OF DOUBLE-NEGATIVE T CELLS IN PATIENTS WITH SYSTEMIC LUPUS ERYHTHEMATOSUS

PubMed Central

Lai, Zhi-Wei; Borsuk, Rebecca; Shadakshari, Ashwini; Yu, Jianghong; Dawood, Maha; Garcia, Ricardo; Francis, Lisa; Tily, Hajra; Bartos, Adam; Faraone, Stephen V.; Phillips, Paul; Perl, Andras

2013-01-01

The mechanistic target of rapamycin (mTOR) is recognized as a sensor of mitochondrial dysfunction and effector of T-cell lineage development, however, its role in autoimmunity, including systemic lupus erythematosus, remains unclear. Here, we prospectively evaluated mitochondrial dysfunction and mTOR activation in PBL relative to SLE disease activity index (SLEDAI) during 274 visits of 59 patients and 54 matched healthy subjects. Partial least square-discriminant analysis identified 15 of 212 parameters that accounted for 70.2% of the total variance and discriminated lupus and control samples (p<0.0005); increased mitochondrial mass of CD3+/CD4−/CD8− double-negative (DN) T cells (p=1.1×10−22) and FoxP3 depletion in CD4+/CD25+ T cells were top contributors (p=6.7×10−7). Prominent necrosis and mTOR activation were noted in DN T cells during 15 visits characterized by flares (SLEDAI increase ≥4) relative to 61 visits of remission (SLEDAI decrease ≥4). mTOR activation in DN T cells was also noted at pre-flare visits of SLE patients relative to those of stable disease or healthy controls. DN lupus T cells showed increased production of IL-4, which correlated with depletion of CD25+/CD19+B cells. Rapamycin treatment in vivo blocked the IL-4 production and necrosis of DN T cells, increased the expression of FoxP3 in CD25+/CD4+T cells, and expanded CD25+/CD19+ B cells. These results identify mTOR activation to be a trigger of IL-4 production and necrotic death of DN T cells in patients with SLE. PMID:23913957

Clinical Predictors of Immune Reconstitution following Combination Antiretroviral Therapy in Patients from the Australian HIV Observational Database

PubMed Central

Rajasuriar, Reena; Gouillou, Maelenn; Spelman, Tim; Read, Tim; Hoy, Jennifer; Law, Matthew; Cameron, Paul U.; Petoumenos, Kathy; Lewin, Sharon R.

2011-01-01

Background A small but significant number of patients do not achieve CD4 T-cell counts >500cells/µl despite years of suppressive cART. These patients remain at risk of AIDS and non-AIDS defining illnesses. The aim of this study was to identify clinical factors associated with CD4 T-cell recovery following long-term cART. Methods Patients with the following inclusion criteria were selected from the Australian HIV Observational Database (AHOD): cART as their first regimen initiated at CD4 T-cell count <500cells/µl, HIV RNA<500copies/ml after 6 months of cART and sustained for at least 12 months. The Cox proportional hazards model was used to identify determinants associated with time to achieve CD4 T-cell counts >500cells/µl and >200cells/µl. Results 501 patients were eligible for inclusion from AHOD (n = 2853). The median (IQR) age and baseline CD4 T-cell counts were 39 (32–47) years and 236 (130–350) cells/µl, respectively. A major strength of this study is the long follow-up duration, median (IQR) = 6.5(3–10) years. Most patients (80%) achieved CD4 T-cell counts >500cells/µl, but in 8%, this took >5 years. Among the patients who failed to reach a CD4 T-cell count >500cells/µl, 16% received cART for >10 years. In a multivariate analysis, faster time to achieve a CD4 T-cell count >500cells/µl was associated with higher baseline CD4 T-cell counts (p<0.001), younger age (p = 0.019) and treatment initiation with a protease inhibitor (PI)-based regimen (vs. non-nucleoside reverse transcriptase inhibitor, NNRTI; p = 0.043). Factors associated with achieving CD4 T-cell counts >200cells/µl included higher baseline CD4 T-cell count (p<0.001), not having a prior AIDS-defining illness (p = 0.018) and higher baseline HIV RNA (p<0.001). Conclusion The time taken to achieve a CD4 T-cell count >500cells/µl despite long-term cART is prolonged in a subset of patients in AHOD. Starting cART early with a PI-based regimen (vs. NNRTI-based regimen) is associated with more rapid recovery of a CD4 T-cell count >500cells/µl. PMID:21674057

Expression of CD30 in patients with acute graft-versus-host disease.

PubMed

Chen, Yi-Bin; McDonough, Sean; Hasserjian, Robert; Chen, Heidi; Coughlin, Erin; Illiano, Christina; Park, In Sun; Jagasia, Madan; Spitzer, Thomas R; Cutler, Corey S; Soiffer, Robert J; Ritz, Jerome

2012-07-19

Acute GVHD (aGVHD) remains a major source of morbidity after allogeneic hematopoietic cell transplantation. CD30 is a cell-surface protein expressed on certain activated T cells. We analyzed CD30 expression on peripheral blood T-cell subsets and soluble CD30 levels in 26 patients at the time of presentation of aGVHD, before the initiation of treatment, compared with 27 patients after hematopoietic cell transplantation without aGVHD (NONE). Analysis by flow cytometry showed that patients with aGVHD had a greater percentage of CD30 expressing CD8(+) T cells with the difference especially pronounced in the central memory subset (CD8(+)CD45RO(+)CD62L(+)): GVHD median 12.4% (range, 0.8%-33.4%) versus NONE 2.1% (0.7%, 17.5%), P < .001. There were similar levels of CD30 expression in naive T cells, CD4(+) T cells, and regulatory (CD4(+)CD127(low)CD25(+)) T cells. Plasma levels of soluble CD30 were significantly greater in patients with GVHD: median 61.7 ng/mL (range, 9.8-357.1 ng/mL) versus 17.4 (range, 3.7-142.4 ng/mL) in NONE (P < .001). Immunohistochemical analysis of affected intestinal tissue showed many CD30(+) infiltrating lymphocytes present. These results suggest that CD30 expression on CD8(+) T-cell subsets or plasma levels of soluble CD30 may be a potential biomarker for aGVHD. CD30 may also represent a target for novel therapeutic approaches for aGVHD.

Expression of CD30 in patients with acute graft-versus-host disease

PubMed Central

McDonough, Sean; Hasserjian, Robert; Chen, Heidi; Coughlin, Erin; Illiano, Christina; Park, In Sun; Jagasia, Madan; Spitzer, Thomas R.; Cutler, Corey S.; Soiffer, Robert J.; Ritz, Jerome

2012-01-01

Acute GVHD (aGVHD) remains a major source of morbidity after allogeneic hematopoietic cell transplantation. CD30 is a cell-surface protein expressed on certain activated T cells. We analyzed CD30 expression on peripheral blood T-cell subsets and soluble CD30 levels in 26 patients at the time of presentation of aGVHD, before the initiation of treatment, compared with 27 patients after hematopoietic cell transplantation without aGVHD (NONE). Analysis by flow cytometry showed that patients with aGVHD had a greater percentage of CD30 expressing CD8+ T cells with the difference especially pronounced in the central memory subset (CD8+CD45RO+CD62L+): GVHD median 12.4% (range, 0.8%-33.4%) versus NONE 2.1% (0.7%, 17.5%), P < .001. There were similar levels of CD30 expression in naive T cells, CD4+ T cells, and regulatory (CD4+CD127lowCD25+) T cells. Plasma levels of soluble CD30 were significantly greater in patients with GVHD: median 61.7 ng/mL (range, 9.8-357.1 ng/mL) versus 17.4 (range, 3.7-142.4 ng/mL) in NONE (P < .001). Immunohistochemical analysis of affected intestinal tissue showed many CD30+ infiltrating lymphocytes present. These results suggest that CD30 expression on CD8+ T-cell subsets or plasma levels of soluble CD30 may be a potential biomarker for aGVHD. CD30 may also represent a target for novel therapeutic approaches for aGVHD. PMID:22661699

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

PubMed

Verhoeven, D; Sankaran, S; Dandekar, S

2007-08-01

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

Memory CD8+ T Cells Protect Dendritic Cells from CTL Killing1

PubMed Central

Watchmaker, Payal B.; Urban, Julie A.; Berk, Erik; Nakamura, Yutaro; Mailliard, Robbie B.; Watkins, Simon C.; van Ham, S. Marieke; Kalinski, Pawel

2010-01-01

CD8+ T cells have been shown to be capable of either suppressing or promoting immune responses. To reconcile these contrasting regulatory functions, we compared the ability of human effector and memory CD8+ T cells to regulate survival and functions of dendritic cells (DC). We report that, in sharp contrast to the effector cells (CTLs) that kill DCs in a granzyme B- and perforin-dependent mechanism, memory CD8+ T cells enhance the ability of DCs to produce IL-12 and to induce functional Th1 and CTL responses in naive CD4+ and CD8+ T cell populations. Moreover, memory CD8+ T cells that release the DC-activating factor TNF-α before the release of cytotoxic granules induce DC expression of an endogenous granzyme B inhibitor PI-9 and protect DCs from CTL killing with similar efficacy as CD4+ Th cells. The currently identified DC-protective function of memory CD8+ T cells helps to explain the phenomenon of CD8+ T cell memory, reduced dependence of recall responses on CD4+ T cell help, and the importance of delayed administration of booster doses of vaccines for the optimal outcome of immunization. PMID:18322193

T-cell phenotype and function following a first cART regimen containing either a protease inhibitor or a non-nucleoside reverse transcriptase inhibitor in HIV-infected late presenters: results from a retrospective, ex vivo study.

PubMed

Tincati, Camilla; Savoldi, Alessia; Cannizzo, E Stefania; Bellistrì, Giusi M; Termini, Roberta; Garau, Marzia; Mancusi, Daniela; d'Arminio Monforte, Antonella; Marchetti, Giulia

2016-01-01

We aimed to comparatively assess darunavir/ritonavir (DRV/r) and efavirenz (EFV)-based first-line cART regimens in the reconstitution of T-cell phenotype and function in HIV-infected, late presenter subjects. Retrospective, ex vivo study on stored peripheral blood mononuclear cell samples of cART-naive, HIV-infected individuals with CD4(+) T-cell counts <50>250/µl upon cART initiation with either DRV/r or EFV as third drugs of standard antiretroviral regimens. CD4(+) and CD8(+) T-cell maturation (CCR7/CD45RA) and proliferation (Ki67), CD8(+) T-cell activation (CD38/HLA-DR) as well as HIV- and cytomegalovirus (CMV)-specific responses (CD4/CD8/IL-2/IFN-γ) were studied by flow cytometry at baseline (T0), T3, T6 and T12 months. Soluble inflammatory markers (IL-6 and sCD14) were measured in plasma at T0 and T12. Wilcoxon and Mann-Whitney tests were used for statistics. A total of 19 patients started DRV/r and 15 EFV. Both regimens accounted for suppression of the HIV RNA load (<40 copies/ml), reconstitution of absolute CD4(+) T-cells and CD4(+)/CD8(+) T-cell ratio. All study participants displayed a significant decrease of activated HLA-DR(+)CD38(+) CD8(+) T-cells at all study time points, yet no differences were found between study groups in T-cell activation and maturation phenotype. From a functional standpoint, only individuals receiving DRV/r displayed transitory recovery of HIV-specific IL-2(+)IFN-γ(-) CD4(+) T-cells (T3: P=0.006) and IL-2(-)IFN-γ(+) CD8(+) T-cells (T3: P=0.032). DRV/r- and EFV-based regimens have an equal effect on T-cell phenotype and function in HIV late presenters. A temporary restoration of HIV-specific T-cell immunity early in the course of therapy with DRV/r possibly implies a more effective control over HIV in the first months following a PI/r-based regimen, even at late stage of disease.

Differential requirements for Runx proteins in CD4 repression and epigenetic silencing during T lymphocyte development.

PubMed

Taniuchi, Ichiro; Osato, Motomi; Egawa, Takeshi; Sunshine, Mary Jean; Bae, Suk Chul; Komori, Toshihisa; Ito, Yoshiaki; Littman, Dan R

2002-11-27

T lymphocytes differentiate in discrete stages within the thymus. Immature thymocytes lacking CD4 and CD8 coreceptors differentiate into double-positive cells (CD4(+)CD8(+)), which are selected to become either CD4(+)CD8(-)helper cells or CD4(-)CD8(+) cytotoxic cells. A stage-specific transcriptional silencer regulates expression of CD4 in both immature and CD4(-)CD8(+) thymocytes. We show here that binding sites for Runt domain transcription factors are essential for CD4 silencer function at both stages, and that different Runx family members are required to fulfill unique functions at each stage. Runx1 is required for active repression in CD4(-)CD8(-) thymocytes whereas Runx3 is required for establishing epigenetic silencing in cytotoxic lineage thymocytes. Runx3-deficient cytotoxic T cells, but not helper cells, have defective responses to antigen, suggesting that Runx proteins have critical functions in lineage specification and homeostasis of CD8-lineage T lymphocytes.

Toll-Like Receptor 2 Ligation Enhances HIV-1 Replication in Activated CCR6+ CD4+ T Cells by Increasing Virus Entry and Establishing a More Permissive Environment to Infection.

PubMed

Bolduc, Jean-François; Ouellet, Michel; Hany, Laurent; Tremblay, Michel J

2017-02-15

In this study, we investigated the effect of Toll-like receptor 2 (TLR2) ligation on the permissiveness of activated CD4 + T cells to HIV-1 infection by focusing our experiments on the relative susceptibility of cell subsets based on their expression of CCR6. Purified primary human CD4 + T cells were first subjected to a CD3/CD28 costimulation before treatment with the TLR2 agonist Pam3CSK4. Finally, cells were inoculated with R5-tropic HIV-1 particles that permit us to study the effect of TLR2 triggering on virus production at both population and single-cell levels. We report here that HIV-1 replication is augmented in CD3/CD28-costimulated CCR6 + CD4 + T cells upon engagement of the cell surface TLR2. Additional studies indicate that a higher virus entry and polymerization of the cortical actin are seen in this cell subset following TLR2 stimulation. A TLR2-mediated increase in the level of phosphorylated NF-κB p65 subunit was also detected in CD3/CD28-costimulated CCR6 + CD4 + T cells. We propose that, upon antigenic presentation, an engagement of TLR2 acts specifically on CCR6 + CD4 + T cells by promoting virus entry in an intracellular milieu more favorable for productive HIV-1 infection. Following primary infection, HIV-1 induces an immunological and structural disruption of the gut mucosa, leading to bacterial translocation and release of microbial components in the bloodstream. These pathogen-derived constituents include several agonists of Toll-like receptors that may affect gut-homing CD4 + T cells, such as those expressing the chemokine receptor CCR6, which are highly permissive to HIV-1 infection. We demonstrate that TLR2 ligation in CD3/CD28-costimulated CCR6 + CD4 + T cells leads to enhanced virus production. Our results highlight the potential impact of bacterial translocation on the overall permissiveness of CCR6 + CD4 + T cells to productive HIV-1 infection. Copyright © 2017 American Society for Microbiology.

Cytokine Expression, Natural Killer Cell Activation, and Phenotypic Changes in Lymphoid Cells from Rhesus Macaques during Acute Infection with Pathogenic Simian Immunodeficiency Virus

PubMed Central

Giavedoni, Luis D.; Velasquillo, M. Cristina; Parodi, Laura M.; Hubbard, Gene B.; Hodara, Vida L.

2000-01-01

We studied the innate and adaptive immune system of rhesus macaques infected with the virulent simian immunodeficiency virus isolate SIVmac251 by evaluating natural killer (NK) cell activity, cytokine levels in plasma, humoral and virological parameters, and changes in the activation markers CD25 (interleukin 2R [IL-2R] α chain), CD69 (early activation marker), and CD154 (CD40 ligand) in lymphoid cells. We found that infection with SIVmac251 induced the sequential production of interferon-α/β (IFN-α/β), IL-18, and IL-12. IFN-γ, IL-4, and granulocyte-macrophage colony-stimulating factor were undetected in plasma by the assays used. NK cell activity peaked at 1 to 2 weeks postinfection and paralleled changes in viral loads. Maximum expression of CD69 on CD3−CD16+ lymphocytes correlated with NK cytotoxicity during this period. CD25 expression, which is associated with proliferation, was static or slightly down-regulated in CD4+ T cells from both peripheral blood (PB) and lymph nodes (LN). CD69, which is normally present in LN CD4+ T cells and absent in peripheral blood leukocyte (PBL) CD4+ T cells, was down-regulated in LN CD4+ T cells and up-regulated in PBL CD4+ T cells immediately after infection. CD8+ T cells increased CD69 but not CD25 expression, indicating the activation of this cellular subset in PB and LN. Finally, CD154 was transiently up-regulated in PBL CD4+ T cells but not in LN CD4+ T cells. Levels of antibodies to SIV Gag and Env did not correlate with the level of activation of CD154, a critical costimulatory molecule for T-cell-dependent immunity. In summary, we present the first documented evidence that the innate immune system of rhesus macaques recognizes SIV infection by sequential production of proinflammatory cytokines and transient activation of NK cytotoxic activity. Additionally, pathogenic SIV induces drastic changes in the level of activation markers on T cells from different anatomic compartments. These changes involve activation in the absence of proliferation, indicating that activation-induced cell death may cause some of the reported increase in lymphocyte turnover during SIV infection. PMID:10644334

Bromelain treatment reduces CD25 expression on activated CD4+ T cells in vitro✩

PubMed Central

Secor, Eric R.; Singh, Anurag; Guernsey, Linda A.; McNamara, Jeff T.; Zhan, Lijun; Maulik, Nilanjana; Thrall, Roger S.

2009-01-01

Bromelain (Br), an extract from pineapple stem with cysteine protease activity, exerts anti-inflammatory effects in a number of inflammatory models. We have previously shown that Br treatment decreased activated CD4+ T cells and has a therapeutic role in an ovalbumin-induced murine model of allergic airway disease. The current study was designed to determine the effect of Br on CD4+ T cell activation, specifically the expression of CD25 in vitro. CD25 is up regulated upon T cell activation, found as a soluble fraction (sCD25) and is a therapeutic target in inflammation, autoimmunity and allergy. Br treatment of anti-CD3 stimulated CD4+ T cells reduced CD25 expression in a dose and time dependent manner. This reduction of CD25 was dependent on the proteolytic action of Br as the addition of E64 (a cysteine protease inhibitor) abrogated this response. The concentration of sCD25 was increased in supernatants of Br treated activated CD4+ T cells as compared to control cells, suggesting that Br proteolytically cleaved cell-surface CD25. This novel mechanism of action identifies how Br may exert its therapeutic benefits in inflammatory conditions. PMID:19162239

CD39 is upregulated during activation of mouse and human T cells and attenuates the immune response to Listeria monocytogenes.

PubMed

Raczkowski, Friederike; Rissiek, Anne; Ricklefs, Isabell; Heiss, Kirsten; Schumacher, Valéa; Wundenberg, Kira; Haag, Friedrich; Koch-Nolte, Friedrich; Tolosa, Eva; Mittrücker, Hans-Willi

2018-01-01

The ectoenzymes CD39 and CD73 degrade extracellular ATP to adenosine. ATP is released by stressed or damaged cells and provides pro-inflammatory signals to immune cells through P2 receptors. Adenosine, on the other hand, suppresses immune cells by stimulating P1 receptors. Thus, CD39 and CD73 can shape the quality of immune responses. Here we demonstrate that upregulation of CD39 is a consistent feature of activated conventional CD4+ and CD8+ T cells. Following stimulation in vitro, CD4+ and CD8+ T cells from human blood gained surface expression of CD39 but displayed only low levels of CD73. Activated human T cells from inflamed joints largely presented with a CD39+CD73- phenotype. In line, in spleens of mice with acute Listeria monocytogenes, listeria-specific CD4+ and CD8+ T cells acquired a CD39+CD73- phenotype. To test the function of CD39 in control of bacterial infection, CD39-deficient (CD39-/-) mice were infected with L. monocytogenes. CD39-/- mice showed better initial control of L. monocytogenes, which was associated with enhanced production of inflammatory cytokines. In the late stage of infection, CD39-/- mice accumulated more listeria-specific CD8+ T cells in the spleen than wildtype animals suggesting that CD39 attenuates the CD8+ T-cell response to infection. In conclusion, our results demonstrate that CD39 is upregulated on conventional CD4+ and CD8+ T cells at sites of acute infection and inflammation, and that CD39 dampens responses to bacterial infection.

Enforced IL-10 Expression Confers Type 1 Regulatory T Cell (Tr1) Phenotype and Function to Human CD4+ T Cells

PubMed Central

Andolfi, Grazia; Fousteri, Georgia; Rossetti, Maura; Magnani, Chiara F; Jofra, Tatiana; Locafaro, Grazia; Bondanza, Attilio; Gregori, Silvia; Roncarolo, Maria-Grazia

2012-01-01

Type 1 regulatory T (Tr1) cells are an inducible subset of CD4+ Tr cells characterized by high levels of interleukin (IL)-10 production and regulatory properties. Several protocols to generate human Tr1 cells have been developed in vitro. However, the resulting population includes a significant fraction of contaminating non-Tr1 cells, representing a major bottleneck for clinical application of Tr1 cell therapy. We generated an homogeneous IL-10–producing Tr1 cell population by transducing human CD4+ T cells with a bidirectional lentiviral vector (LV) encoding for human IL-10 and the marker gene, green fluorescent protein (GFP), which are independently coexpressed. The resulting GFP+ LV-IL-10–transduced human CD4+ T (CD4LV-IL-10) cells expressed, upon T-cell receptor (TCR) activation, high levels of IL-10 and concomitant low levels of IL-4, and markers associated with IL-10. Moreover, CD4LV-IL-10 T cells displayed typical Tr1 features: the anergic phenotype, the IL-10, and transforming growth factor (TGF)-β dependent suppression of allogeneic T-cell responses, and the ability to suppress in a cell-to-cell contact independent manner in vitro. CD4LV-IL-10 T cells were able to control xeno graft-versus-host disease (GvHD), demonstrating their suppressive function in vivo. These results show that constitutive over-expression of IL-10 in human CD4+ T cells leads to a stable cell population that recapitulates the phenotype and function of Tr1 cells. PMID:22692497

Comprehensive Mass Cytometry Analysis of Cell Cycle, Activation, and Coinhibitory Receptors Expression in CD4 T Cells from Healthy and HIV-Infected Individuals.

PubMed

Corneau, Aurélien; Cosma, Antonio; Even, Sophie; Katlama, Christine; Le Grand, Roger; Frachet, Véronique; Blanc, Catherine; Autran, Brigitte

2017-01-01

Mass cytometry allows large multiplex analysis of cell cycle stages together with differentiation, activation, and exhaustion markers, allowing further assessment of the quiescence status of resting CD4 T cells. Peripheral blood CD4 T lymphocytes from 8 individuals, 4 healthy donors, and 4 HIV-infected on antiretroviral treatment (T) were stained with the same 26 monoclonal antibodies and dyes targeting surface and intracellular markers of differentiation, activation, exhaustion, and cell cycle stages. Samples were run on a CYTOF-2. Patterns of naïve [TN] CD4 T cells strongly differed from all other memory subsets central-memory (CM), transitional-memory (TM), effector-memory (EM), and terminally differentiated RA-expressing (TEMRA) subsets, while stem-cell memory (SCM) and T follicular-helper cells (TfH) were close to CM and TM cells with the highest percentages in cell cycle. EM and TEMRA were the most altered by HIV infection, with an increased frequency of activated and cycling cells. Activation markers and coinhibitory receptor expression differed among cell cycle stages, with HLA-DR fitting better than CD25 or CD38 with cycle, and opposite PD-1 gradients along differentiation and cell cycle. "Resting" DR-CD25- CD4+ T cells contained similar amounts of cells in G1 than the activated DR ± CD25± ones but three fold lower cells in S-G2-M. This broad multiplex mass cytometry analysis demonstrates some subsets of the so-called "resting" CD25-DR- CD4+ T cells contain noticeable amounts of cells into cycle or expressing coinhibitory receptors, opening new avenues for a redefinition of resting peripheral blood CD4 T cells harboring the HIV reservoirs. © 2016 International Clinical Cytometry Society. © 2016 International Clinical Cytometry Society.

Characteristics of Prevotella intermedia-specific CD4+ T cell clones from peripheral blood of a chronic adult periodontitis patient

PubMed Central

Wassenaar, A; Reinhardus, C; Abraham-Inpijn, L; Snijders, A; Kievits, F

1998-01-01

Periodontitis is a chronic destructive inflammatory disease associated with periodontopathic bacteria. In addition, autoantigens such as collagen and heat shock proteins (hsp) have been suggested to play a role. Established periodontal lesions are characterized by dense infiltrations of immune cells such as cytokine-producing CD4+ and CD8+ T cells. CD4+ T cells specific for Prevotella intermedia can be isolated from lesional gingiva, suggesting an active role for CD4+ T cells in the response to this bacterium. We therefore investigated the characteristics of a panel of 13 P. intermedia-specific CD4+ T cells generated from the peripheral blood of a patient with chronic adult periodontitis. All 13 P. intermedia-specific CD4+ T cells recognized the antigens in the context of HLA-DR. The T cell clones were mainly classified as Th0, producing comparable amounts of interferon-gamma (IFN-γ) and IL-4, and Th2, producing high amounts of IL-4 and almost no IFN-γ. None of the P. intermedia-specific T cell clones recognized antigens of the periodontopathic bacteria Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis and of the autoantigens collagen and hsp. The reactivity profile of the T cell clones to size-fractionated cell envelope antigens of P. intermedia indicated that P. intermedia-specific CD4+ T cell clones recognize probably five different antigen specificities in the context of the MHC class II molecules, DR7 or DR15. These results suggest that a broad panel of cell-associated protein antigens play a role in the induction of P. intermedia-specific CD4+ T cell response. PMID:9697992

Interleukin 4-producing CD4+ T cells in the skin of cats with allergic dermatitis.

PubMed

Roosje, P J; Dean, G A; Willemse, T; Rutten, V P M G; Thepen, T

2002-03-01

Lesional skin of cats with allergic dermatitis has a cellular infiltrate and a CD4/CD8 ratio comparable to that in humans with atopic dermatitis. CD4+ helper T cells and in particular cells belonging to the Th2 subset play an important role in disease pathogenesis in humans. We investigated the cytokine pattern of CD4+ T cells in situ, with special emphasis on the putative presence of cells producing interleukin 4 (IL4), in cats with allergic dermatitis. Immunohistochemical procedures were used to determine that CD4+ T cells in lesional and nonlesional skin of cats with allergic dermatitis can produce IL4, as occurs in humans. Lesional and nonlesional skin of cats with allergic dermatitis had significantly more IL4+ T cells (P = 0.001) than did skin of healthy control cats. Double staining indicated that all IL4+ cells were positive for pan-T or CD4 markers. Double labeling for mast cell chymase and IL4 stained primarily different cells. Western blotting demonstrated cross-reactivity between the antibody against human IL4 and a feline recombinant IL4. These results indicate that IL4 is primarily produced by CD4+ T cells and is also present in clinically uninvolved skin, indicating a role in the pathogenesis of allergic dermatitis in cats.

A transcriptome-based model of central memory CD4 T cell death in HIV infection.

PubMed

Olvera-García, Gustavo; Aguilar-García, Tania; Gutiérrez-Jasso, Fany; Imaz-Rosshandler, Iván; Rangel-Escareño, Claudia; Orozco, Lorena; Aguilar-Delfín, Irma; Vázquez-Pérez, Joel A; Zúñiga, Joaquín; Pérez-Patrigeon, Santiago; Espinosa, Enrique

2016-11-22

Human central memory CD4 T cells are characterized by their capacity of proliferation and differentiation into effector memory CD4 T cells. Homeostasis of central memory CD4 T cells is considered a key factor sustaining the asymptomatic stage of Human Immunodeficiency Virus type 1 (HIV-1) infection, while progression to acquired immunodeficiency syndrome is imputed to central memory CD4 T cells homeostatic failure. We investigated if central memory CD4 T cells from patients with HIV-1 infection have a gene expression profile impeding proliferation and survival, despite their activated state. Using gene expression microarrays, we analyzed mRNA expression patterns in naive, central memory, and effector memory CD4 T cells from healthy controls, and naive and central memory CD4 T cells from patients with HIV-1 infection. Differentially expressed genes, defined by Log 2 Fold Change (FC) ≥ |0.5| and Log (odds) > 0, were used in pathway enrichment analyses. Central memory CD4 T cells from patients and controls showed comparable expression of differentiation-related genes, ruling out an effector-like differentiation of central memory CD4 T cells in HIV infection. However, 210 genes were differentially expressed in central memory CD4 T cells from patients compared with those from controls. Expression of 75 of these genes was validated by semi quantitative RT-PCR, and independently reproduced enrichment results from this gene expression signature. The results of functional enrichment analysis indicated movement to cell cycle phases G1 and S (increased CCNE1, MKI67, IL12RB2, ADAM9, decreased FGF9, etc.), but also arrest in G2/M (increased CHK1, RBBP8, KIF11, etc.). Unexpectedly, the results also suggested decreased apoptosis (increased CSTA, NFKBIA, decreased RNASEL, etc.). Results also suggested increased IL-1β, IFN-γ, TNF, and RANTES (CCR5) activity upstream of the central memory CD4 T cells signature, consistent with the demonstrated milieu in HIV infection. Our findings support a model where progressive loss of central memory CD4 T cells in chronic HIV-1 infection is driven by increased cell cycle entry followed by mitotic arrest, leading to a non-apoptotic death pathway without actual proliferation, possibly contributing to increased turnover.

Thermal injury-plus-sepsis contributes to a substantial deletion of intestinal mesenteric lymph node CD4 T cell via apoptosis.

PubMed

Fazal, Nadeem; Al-Ghoul, Walid M

2007-09-12

Thermal injury (TI) with septic complications continues to be a serious clinical problem. One of the main concerns in such patients is immunosuppression related to functional derangements in intestinal CD4+ T lymphocytes. Extensive previous studies in thermal injury/septic patients and animal models of thermal injury/sepsis have shown decreased responsiveness of intestinal CD4+ T cells to antigen/mitogen. This hyporesponsiveness could significantly contribute to increase injured host susceptibility to pathogens including those translocating from host's gut lumen. Our previous studies indicated that while thermal injury or sepsis alone lead to suppressed proliferation and IL-2 production of intestinal CD4+ T cells, this study showed a substantial deletion via apoptosis of the Mesenteric Lymph Nodes (MLN) CD4+ T cells. Hence, thermal injury-plus-sepsis contributes not only to suppressed CD4+ T proliferation/IL-2 production but also to a substantial modulation of CD4+ T cell survivability. These findings allow us to conclude that while thermal injury alone can produce attenuated cell mediated responses without an overt change in CD4+ T cell survival, thermal injury with septic complications causes CD4+ T cell death and an irreversible loss of cell-mediated responses. The latter happening could be responsible for high morbidity and mortality in the injured host afflicted with thermal injury plus a critical infection.

Thermal injury-plus-sepsis contributes to a substantial deletion of intestinal mesenteric lymph node CD4+ T cell via apoptosis

PubMed Central

Fazal, Nadeem; Al-Ghoul, Walid M

2007-01-01

Thermal injury (TI) with septic complications continues to be a serious clinical problem. One of the main concerns in such patients is immunosuppression related to functional derangements in intestinal CD4+ T lymphocytes. Extensive previous studies in thermal injury/septic patients and animal models of thermal injury/sepsis have shown decreased responsiveness of intestinal CD4+ T cells to antigen/mitogen. This hyporesponsiveness could significantly contribute to increase injured host susceptibility to pathogens including those translocating from host's gut lumen. Our previous studies indicated that while thermal injury or sepsis alone lead to suppressed proliferation and IL-2 production of intestinal CD4+ T cells, this study showed a substantial deletion via apoptosis of the Mesenteric Lymph Nodes (MLN) CD4+ T cells. Hence, thermal injury-plus-sepsis contributes not only to suppressed CD4+ T proliferation/IL-2 production but also to a substantial modulation of CD4+ T cell survivability. These findings allow us to conclude that while thermal injury alone can produce attenuated cell mediated responses without an overt change in CD4+ T cell survival, thermal injury with septic complications causes CD4+ T cell death and an irreversible loss of cell-mediated responses. The latter happening could be responsible for high morbidity and mortality in the injured host afflicted with thermal injury plus a critical infection. PMID:17895960

CD8{sup +}CD25{sup +} T cells reduce atherosclerosis in apoE(−/−) mice

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

Zhou, Jianchang; Dimayuga, Paul C.; Zhao, Xiaoning

2014-01-17

Highlights: •The role of a sub-population of CD8{sup +} T cells with suppressor functions was investigated in atherosclerosis. •CD8{sup +}CD25{sup +} T cells from adult apoE(−/−) mice had phenotype characteristics of T suppressor cells. •These CD8{sup +}CD25{sup +} T cells reduced CD4{sup +} T cell proliferation and CD8{sup +} cytotoxic activity in vitro. •Adoptive transfer of CD8{sup +}CD25{sup +} T cells significantly reduced atherosclerosis. •CD8{sup +}CD25{sup +} T cells have a suppressive function in atherosclerosis. -- Abstract: Background: It is increasingly evident that CD8{sup +} T cells are involved in atherosclerosis but the specific subtypes have yet to be defined.more » CD8{sup +}CD25{sup +} T cells exert suppressive effects on immune signaling and modulate experimental autoimmune disorders but their role in atherosclerosis remains to be determined. The phenotype and functional role of CD8{sup +}CD25{sup +} T cells in experimental atherosclerosis were investigated in this study. Methods and results: CD8{sup +}CD25{sup +} T cells were observed in atherosclerotic plaques of apoE(−/−) mice fed hypercholesterolemic diet. Characterization by flow cytometric analysis and functional evaluation using a CFSE-based proliferation assays revealed a suppressive phenotype and function of splenic CD8{sup +}CD25{sup +} T cells from apoE(−/−) mice. Depletion of CD8{sup +}CD25{sup +} from total CD8{sup +} T cells rendered higher cytolytic activity of the remaining CD8{sup +}CD25{sup −} T cells. Adoptive transfer of CD8{sup +}CD25{sup +} T cells into apoE(−/−) mice suppressed the proliferation of splenic CD4{sup +} T cells and significantly reduced atherosclerosis in recipient mice. Conclusions: Our study has identified an athero-protective role for CD8{sup +}CD25{sup +} T cells in experimental atherosclerosis.« less

Parasite Fate and Involvement of Infected Cells in the Induction of CD4+ and CD8+ T Cell Responses to Toxoplasma gondii

PubMed Central

Dupont, Christopher D.; Christian, David A.; Selleck, Elizabeth M.; Pepper, Marion; Leney-Greene, Michael; Harms Pritchard, Gretchen; Koshy, Anita A.; Wagage, Sagie; Reuter, Morgan A.; Sibley, L. David; Betts, Michael R.; Hunter, Christopher A.

2014-01-01

During infection with the intracellular parasite Toxoplasma gondii, the presentation of parasite-derived antigens to CD4+ and CD8+ T cells is essential for long-term resistance to this pathogen. Fundamental questions remain regarding the roles of phagocytosis and active invasion in the events that lead to the processing and presentation of parasite antigens. To understand the most proximal events in this process, an attenuated non-replicating strain of T. gondii (the cpsII strain) was combined with a cytometry-based approach to distinguish active invasion from phagocytic uptake. In vivo studies revealed that T. gondii disproportionately infected dendritic cells and macrophages, and that infected dendritic cells and macrophages displayed an activated phenotype characterized by enhanced levels of CD86 compared to cells that had phagocytosed the parasite, thus suggesting a role for these cells in priming naïve T cells. Indeed, dendritic cells were required for optimal CD4+ and CD8+ T cell responses, and the phagocytosis of heat-killed or invasion-blocked parasites was not sufficient to induce T cell responses. Rather, the selective transfer of cpsII-infected dendritic cells or macrophages (but not those that had phagocytosed the parasite) to naïve mice potently induced CD4+ and CD8+ T cell responses, and conferred protection against challenge with virulent T. gondii. Collectively, these results point toward a critical role for actively infected host cells in initiating T. gondii-specific CD4+ and CD8+ T cell responses. PMID:24722202

Immune Cell-Mediated Protection against Vaginal Candidiasis: Evidence for a Major Role of Vaginal CD4+ T Cells and Possible Participation of Other Local Lymphocyte Effectors

PubMed Central

Santoni, Giorgio; Boccanera, Maria; Adriani, Daniela; Lucciarini, Roberta; Amantini, Consuelo; Morrone, Stefania; Cassone, Antonio; De Bernardis, Flavia

2002-01-01

The protective roles of different lymphocyte subsets were investigated in a rat vaginal candidiasis model by adoptive transfer of vaginal lymphocytes (VL) or sorted, purified CD3+ T cells, CD4+ or CD8+ T cells, or CD3− CD5+ B cells from the vaginas of naïve or immune rats following three rounds of Candida albicans infection. The adoptive transfer of total VL from nonimmune animals did not alter the course of vaginal candidiasis of the recipient rats. In contrast, the animals receiving total VL or CD3+ T cells from immune rats showed a highly significant acceleration of fungus clearance compared with animals which received nonimmune VL. The animals with vaginal CD3− CD5+ B cells transferred from immune rats also had fewer Candida CFU than the controls, but fungal clearance was significantly retarded with respect to the animals administered immune T cells. Sorted, purified CD4+ and CD8+ vaginal T cells from immune rats were also adoptively transferred to naïve animals. Although both populations were seen to accelerate the clearance of the fungus from the vagina, CD4+ T cells were much more effective than CD8+ T cells. Overall, there was no difference between the antifungal effects of immune vaginal CD4+ T cells and those achievable with the transfer of whole, immune VL. Histological observations of the vaginal tissues of rats with adoptively transferred immune T cells demonstrated a remarkable accumulation of lymphocytes in the subepithelial lamina propria and also infiltrating the mucosal epithelium. These results strongly suggest that distinct vaginal lymphocyte subsets participate in the adaptive anti-Candida immunity at the vaginal level, with the vaginal CD4+ T cells probably playing a major role. PMID:12183521

OX40 signaling is involved in the autoactivation of CD4+CD28- T cells and contributes to the pathogenesis of autoimmune arthritis.

PubMed

Jiang, Juean; Liu, Cuiping; Liu, Mi; Shen, Yu; Hu, Xiaohan; Wang, Qin; Wu, Jian; Wu, Min; Fang, Qi; Zhang, Xueguang

2017-03-21

CD4 + CD28 - T cells exhibit autoreactive potential in autoimmune disorders, including rheumatoid arthritis (RA). It is not well known which costimulator functions as an alternative second signal in the activation of this subset after CD28 expression is downregulated. Tumor necrosis factor receptor superfamily member OX40 is a key costimulator in the activation of T cells. The aim of this study was to investigate the costimulatory effects of OX40 on CD4 + CD28 - T cells in autoimmune arthritis. Clinical samples were collected from patients with RA and control subjects. Collagen-induced arthritis (CIA) was induced with collagen type II (CII) in DBA/1 mice. The CD4 + CD28 - OX40 + T-cell subset and its cytokine production were detected by flow cytometry. After T-cell purification, adoptive transfer was performed in CIA mice. The regulatory role of OX40 was determined by blocking experiments in vitro and in vivo. OX40 and OX40L were abnormally expressed in patients with RA and CIA mice. Further analysis showed that CD4 + CD28 - OX40 + T cells accumulated in patients with RA and in animal models. These cells produced higher levels of proinflammatory cytokines and were closely correlated with the clinicopathological features of the affected individuals. Adoptive transfer of CII-specific CD4 + CD28 - OX40 + T cells remarkably aggravated arthritic development and joint pathology in CIA mice. Moreover, OX40 blockade significantly reduced the proinflammatory responses and ameliorated arthritis development. OX40 acts as an alternative costimulator of CD4 + CD28 - T cells and plays a pathogenic role in autoimmune arthritic development, suggesting that it is a potential target for immunomodulatory therapy of RA.

CD147 modulates the differentiation of T-helper 17 cells in patients with rheumatoid arthritis.

PubMed

Yang, Hui; Wang, Jian; Li, Yu; Yin, Zhen-Jie; Lv, Ting-Ting; Zhu, Ping; Zhang, Yan

2017-01-01

The role of CD147 in regulation of rheumatoid arthritis (RA) is not fully elucidated. The aim of this study was to investigate the effect of cell-to-cell contact of activated CD14 + monocytes with CD4 + T cells, and the modulatory role of CD147 on T-helper 17 (Th17) cells differentiation in patients with RA. Twenty confirmed active RA patients and twenty normal controls were enrolled. CD4 + T cells and CD14 + monocytes were purified by magnetic beads cell sorting. Cells were cultured under different conditions in CD4 + T cells alone, direct cell-to-cell contact co-culture of CD4 + and CD14 + cells, or indirect transwell co-culture of CD4 + /CD14 + cells in response to LPS and anti-CD3 stimulation with or without anti-CD147 antibody pretreatments. The proportion of IL-17-producing CD4 + T cells (defined as Th17 cells) was determined by flow cytometry. The levels of interleukin (IL)-17, IL-6, and IL-1β in the supernatants of cultured cells were measured by ELISA. The optimal condition for in vitro induction of Th17 cells differentiation was co-stimulation with 0.1 μg/mL of LPS and 100 ng/mL of anti-CD3 for 3 days under direct cell-to-cell contact co-culture of CD4 + and CD14 + cells. Anti-CD147 antibody reduced the proportion of Th17 cells, and also inhibited the productions of IL-17, IL-6, and IL-1β in PBMC culture from RA patients. The current results revealed that Th17 differentiation required cell-to-cell contact with activated monocytes. CD147 promoted the differentiation of Th17 cells by regulation of cytokine production, which provided the evidence for pathogenesis and potential therapeutic targets for RA. © 2016 APMIS. Published by John Wiley & Sons Ltd.

CD8+ T cells of chronic HCV-infected patients express multiple negative immune checkpoints following stimulation with HCV peptides.

PubMed

Barathan, Muttiah; Mohamed, Rosmawati; Vadivelu, Jamuna; Chang, Li Yen; Vignesh, Ramachandran; Krishnan, Jayalakshmi; Sigamani, Panneer; Saeidi, Alireza; Ram, M Ravishankar; Velu, Vijayakumar; Larsson, Marie; Shankar, Esaki M

2017-03-01

Hepatitis C virus (HCV)-specific CD4+ and CD8+ T cells are key to successful viral clearance in HCV disease. Accumulation of exhausted HCV-specific T cells during chronic infection results in considerable loss of protective functional immune responses. The role of T-cell exhaustion in chronic HCV disease remains poorly understood. Here, we studied the frequency of HCV peptide-stimulated T cells expressing negative immune checkpoints (PD-1, CTLA-4, TRAIL, TIM-3 and BTLA) by flow cytometry, and measured the levels of Th1/Th2/Th17 cytokines secreted by T cells by a commercial Multi-Analyte ELISArray™ following in vitro stimulation of T cells using HCV peptides and phytohemagglutinin (PHA). HCV peptide-stimulated CD4+ and CD8+ T cells of chronic HCV (CHC) patients showed significant increase of CTLA-4. Furthermore, HCV peptide-stimulated CD4+ T cells of CHC patients also displayed relatively higher levels of PD-1 and TRAIL, whereas TIM-3 was up-regulated on HCV peptide-stimulated CD8+ T cells. Whereas the levels of IL-10 and TGF-β1 were significantly increased, the levels of pro-inflammatory cytokines IL-2, TNF-α, IL-17A and IL-6 were markedly decreased in the T cell cultures of CHC patients. Chronic HCV infection results in functional exhaustion of CD4+ and CD8+ T cells likely contributing to viral persistence. Copyright © 2016 Elsevier Inc. All rights reserved.

Preferential effects of leptin on CD4 T cells in central and peripheral immune system are critically linked to the expression of leptin receptor

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

Kim, So Yong; Lim, Ju Hyun; Choi, Sung Won

2010-04-09

Leptin can enhance thymopoiesis and modulate the T-cell immune response. However, it remains controversial whether these effects correlate with the expression of leptin receptor, ObR. We herein addressed this issue by using in vivo animal models and in vitro culture systems. Leptin treatment in both ob/ob mice and normal young mice induced increases of CD4 SP thymocytes in thymus and CD4 T cells in the periphery. Interestingly, expression of the long form ObR was significantly restricted to DN, DP and CD4 SP, but not CD8 SP thymocytes. Moreover, in the reaggregated DP thymocyte cultures with leptin plus TSCs, leptin profoundlymore » induced differentiation of CD4 SP but not CD8 SP thymocytes, suggesting that the effects of leptin on thymocyte differentiation might be closely related to the expression of leptin receptor in developing thymocytes. Surprisingly, ObR expression was markedly higher in peripheral CD4 T cells than that in CD8 T cells. Furthermore, leptin treatment with or without IL-2 and PHA had preferential effects on cell proliferation of CD4 T cells compared to that of CD8 T cells. Collectively, these data provide evidence that the effects of leptin on differentiation and proliferation of CD4 T cells might be closely related to the expression of leptin receptor.« less

CD4+ T-cell responses to foot-and-mouth disease virus in vaccinated cattle.

PubMed

Carr, B Veronica; Lefevre, Eric A; Windsor, Miriam A; Inghese, Cristina; Gubbins, Simon; Prentice, Helen; Juleff, Nicholas D; Charleston, Bryan

2013-01-01

We have performed a series of studies to investigate the role of CD4(+) T-cells in the immune response to foot-and-mouth disease virus (FMDV) post-vaccination. Virus neutralizing antibody titres (VNT) in cattle vaccinated with killed FMD commercial vaccine were significantly reduced and class switching delayed as a consequence of rigorous in vivo CD4(+) T-cell depletion. Further studies were performed to examine whether the magnitude of T-cell proliferative responses correlated with the antibody responses. FMD vaccination was found to induce T-cell proliferative responses, with CD4(+) T-cells responding specifically to the FMDV antigen. In addition, gamma interferon (IFN-γ) was detected in the supernatant of FMDV antigen-stimulated PBMC and purified CD4(+) T-cells from vaccinated cattle. Similarly, intracellular IFN-γ could be detected specifically in purified CD4(+) T-cells after restimulation. It was not possible to correlate in vitro proliferative responses or IFN-γ production of PBMC with VNT, probably as a consequence of the induction of T-independent and T-dependent antibody responses and antigen non-specific T-cell responses. However, our studies demonstrate the importance of stimulating CD4(+) T-cell responses for the induction of optimum antibody responses to FMD-killed vaccines.

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

PubMed Central

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

2009-01-01

OBJECTIVE Tumor necrosis factor ligand family members B-cell–activating factor (BAFF) and a proliferation-inducing ligand (APRIL) can exert powerful effects on B-cell activation and development, type 1 T-helper cell (Th1) immune responses, and autoimmunity. We examined the effect of blocking BAFF and APRIL on the development of autoimmune diabetes. RESEARCH DESIGN AND METHODS Female NOD mice were administered B-cell maturation antigen (BCMA)-Fc from 9 to 15 weeks of age. Diabetes incidence, islet pathology, and T- and B-cell populations were examined. RESULTS BCMA-Fc treatment reduced the severity of insulitis and prevented diabetes development in NOD mice. BCMA-Fc–treated mice showed reduced follicular, marginal-zone, and T2MZ B-cells. B-cell reduction was accompanied by decreased frequencies of pathogenic CD4+CD40+ T-cells and reduced Th1 cytokines IL-7, IL-15, and IL-17. Thus, T-cell activation was blunted with reduced B-cells. However, BCMA-Fc–treated mice still harbored detectable diabetogenic T-cells, suggesting that regulatory mechanisms contributed to diabetes prevention. Indeed, BCMA-Fc–treated mice accumulated increased CD4+CD25+ regulatory T-cells (Tregs) with age. CD4+CD25+ cells were essential for maintaining euglycemia because their depletion abrogated BCMA-Fc–mediated protection. BCMA-Fc did not directly affect Treg homeostasis given that CD4+CD25+Foxp3+ T-cells did not express TACI or BR3 receptors and that CD4+CD25+Foxp3+ T-cell frequencies were equivalent in wild-type, BAFF−/−, TACI−/−, BCMA−/−, and BR3−/− mice. Rather, B-cell depletion resulted in CD4+CD25+ T-cell–mediated protection from diabetes because anti-CD25 monoclonal antibody treatment precipitated diabetes in both diabetes-resistant NOD.μMT−/− and BCMA-Fc–treated mice. CONCLUSIONS BAFF/APRIL blockade prevents diabetes. BCMA-Fc reduces B-cells, subsequently blunting autoimmune activity and allowing endogenous regulatory mechanisms to preserve a prehyperglycemic state. PMID:19336675

CD4 and CD8 T-Cell Responses to Mycobacterial Antigens in African Children

PubMed Central

Tena-Coki, Nontobeko G.; Scriba, Thomas J.; Peteni, Nomathemba; Eley, Brian; Wilkinson, Robert J.; Andersen, Peter; Hanekom, Willem A.; Kampmann, Beate

2010-01-01

Rationale: The current tuberculosis (TB) vaccine, bacille Calmette-Guérin (BCG), does not provide adequate protection against TB disease in children. Furthermore, more efficacious TB vaccines are needed for children with immunodeficiencies such as HIV infection, who are at highest risk of disease. Objectives: To characterize mycobacteria-specific T cells in children who might benefit from vaccination against TB, focusing on responses to antigens contained in novel TB vaccines. Methods: Whole blood was collected from three groups of BCG-vaccinated children: HIV-seronegative children receiving TB treatment (n = 30), HIV-infected children (n = 30), and HIV-unexposed healthy children (n = 30). Blood was stimulated with Ag85B and TB10.4, or purified protein derivative, and T-cell cytokine production by CD4 and CD8 was determined by flow cytometry. The memory phenotype of antigen-specific CD4 and CD8 T cells was also determined. Measurements and Main Results: Mycobacteria-specific CD4 and CD8 T-cell responses were detectable in all three groups of children. Children receiving TB treatment had significantly higher frequencies of antigen-specific CD4 T cells compared with HIV-infected children (P = 0.0176). No significant differences in magnitude, function, or phenotype of specific T cells were observed in HIV-infected children compared with healthy control subjects. CD4 T cells expressing IFN-γ, IL-2, or both expressed a CD45RA−CCR7−CD27+/− effector memory phenotype. Mycobacteria-specific CD8 T cells expressed mostly IFN-γ in all groups of children; these cells expressed CD45RA−CCR7−CD27+/− or CD45RA+CCR7−CD27+/− effector memory phenotypes. Conclusions: Mycobacteria-specific T-cell responses could be demonstrated in all groups of children, suggesting that the responses could be boosted by new TB vaccines currently in clinical trials. PMID:20224065

Mycobacterium tuberculosis specific CD8(+) T cells rapidly decline with antituberculosis treatment.

PubMed

Nyendak, Melissa R; Park, Byung; Null, Megan D; Baseke, Joy; Swarbrick, Gwendolyn; Mayanja-Kizza, Harriet; Nsereko, Mary; Johnson, Denise F; Gitta, Phineas; Okwera, Alphonse; Goldberg, Stefan; Bozeman, Lorna; Johnson, John L; Boom, W Henry; Lewinsohn, Deborah A; Lewinsohn, David M

2013-01-01

Biomarkers associated with response to therapy in tuberculosis could have broad clinical utility. We postulated that the frequency of Mycobacterium tuberculosis (Mtb) specific CD8(+) T cells, by virtue of detecting intracellular infection, could be a surrogate marker of response to therapy and would decrease during effective antituberculosis treatment. We sought to determine the relationship of Mtb specific CD4(+) T cells and CD8(+) T cells with duration of antituberculosis treatment. We performed a prospective cohort study, enrolling between June 2008 and August 2010, of HIV-uninfected Ugandan adults (n = 50) with acid-fast bacillus smear-positive, culture confirmed pulmonary TB at the onset of antituberculosis treatment and the Mtb specific CD4(+) and CD8(+) T cell responses to ESAT-6 and CFP-10 were measured by IFN-γ ELISPOT at enrollment, week 8 and 24. There was a significant difference in the Mtb specific CD8(+) T response, but not the CD4(+) T cell response, over 24 weeks of antituberculosis treatment (p<0.0001), with an early difference observed at 8 weeks of therapy (p = 0.023). At 24 weeks, the estimated Mtb specific CD8(+) T cell response decreased by 58%. In contrast, there was no significant difference in the Mtb specific CD4(+) T cell during the treatment. The Mtb specific CD4(+) T cell response, but not the CD8(+) response, was negatively impacted by the body mass index. Our data provide evidence that the Mtb specific CD8(+) T cell response declines with antituberculosis treatment and could be a surrogate marker of response to therapy. Additional research is needed to determine if the Mtb specific CD8(+) T cell response can detect early treatment failure, relapse, or to predict disease progression.

Transforming growth factor beta induced FoxP3+ regulatory T cells suppress Th1 mediated experimental colitis.

PubMed

Fantini, M C; Becker, C; Tubbe, I; Nikolaev, A; Lehr, H A; Galle, P; Neurath, M F

2006-05-01

The imbalance between effector and regulatory T cells plays a central role in the pathogenesis of inflammatory bowel diseases. In addition to the thymus, CD4+CD25+ regulatory T cells can be induced in the periphery from a population of CD25- T cells by treatment with transforming growth factor beta (TGF-beta). Here, we analysed the in vivo function of TGF-beta induced regulatory T (Ti-Treg) cells in experimental colitis. Ti-Treg cells were generated in cell culture in the presence or absence of TGF-beta and tested for their regulatory potential in experimental colitis using the CD4+CD62L+ T cell transfer model. Ti-Treg cells significantly suppressed Th1 mediated colitis on CD4+CD62L+ T cell transfer in vivo, as shown by high resolution endoscopy, histology, immunohistochemistry, and cytokine analysis. Further analysis of in vivo and in vitro expanded Ti-Treg cells showed that exogenous interleukin 2 (IL-2) was crucial for survival and expansion of these cells. Our data suggest that regulatory Ti-Treg cells expand by TGF-beta and exogenous IL-2 derived from effector T cells at the site of inflammation. In addition to Tr1 and thymic CD4+CD25+ T cells, peripheral Ti-Treg cells emerge as a class of regulatory T cells with therapeutic potential in T cell mediated chronic intestinal inflammation.

Intestinal double-positive CD4+CD8+ T cells are highly activated memory cells with an increased capacity to produce cytokines.

PubMed

Pahar, Bapi; Lackner, Andrew A; Veazey, Ronald S

2006-03-01

Peripheral blood and intestinal CD4+CD8+ double-positive (DP) T cells have been described in several species including humans, but their function and immunophenotypic characteristics are still not clearly understood. Here we demonstrate that DP T cells are abundant in the intestinal lamina propria of normal rhesus macaques (Macaca mulatta). Moreover, DP T cells have a memory phenotype and are capable of producing different and/or higher levels of cytokines and chemokines in response to mitogen stimulation compared to CD4+ single-positive T cells. Intestinal DP T cells are also highly activated and have higher expression of CCR5, which makes them preferred targets for simian immunodeficiency virus/HIV infection. Increased levels of CD69, CD25 and HLA-DR, and lower CD62L expression were found on intestinal DP T cells populations compared to CD4+ single-positive T cells. Collectively, these findings demonstrate that intestinal and peripheral blood DP T cells are effector cells and may be important in regulating immune responses, which distinguishes them from the immature DP cells found in the thymus. Finally, these intestinal DP T cells may be important target cells for HIV infection and replication due to their activation, memory phenotype and high expression of CCR5.

Multicolor flow-cytometric analysis of milk allergen-specific T-helper type 2 cells revealed coexpression of interleukin-4 with Foxp3.

PubMed

Yamawaki, Kazuo; Inuo, Chisato; Nomura, Takayasu; Tanaka, Kenichi; Nakajima, Yoichi; Kondo, Yasuto; Yoshikawa, Tetsushi; Urisu, Atsuo; Tsuge, Ikuya

2015-12-01

Allergen-specific T-helper type 2 (TH2) cells play an important role in the development of allergic inflammation; however, investigations of the properties of allergen-specific T cells have been challenging in humans. Despite clear evidence that forkhead box p3 (Foxp3) is expressed in conventional effector T cells, its function has remained unknown. To characterize allergen-specific TH2 cells in milk allergy, with particular focus on the expression of Foxp3. Twenty-one children with milk allergy and 11 children without milk allergy were studied. Peripheral blood mononuclear cells from subjects were stimulated with milk allergen for 6 hours and analyzed using multicolor flow cytometry to identify CD154(+) allergen-specific T-helper cells. Simultaneously, the expression of intracellular cytokines and Foxp3 was analyzed. The milk allergy group had significantly larger numbers of milk allergen-specific interleukin (IL)-4- and IL-5-producing CD4(+) T cells than the control group. Subjects in the milk allergy group had significantly more CD154(+)CD4(+) IL-10-producing cells and CD154(+)Foxp3(+)CD4(+) cells than those in the control group. In addition, the number of milk allergen-specific CD154(+)Foxp3(+)CD4(+) cells strongly correlated with that of CD154(+)IL4(+)CD4(+) cells. Bcl-2 expression in CD154(+)IL-4(+)Foxp3(+) T-helper cells was significantly lower compared with that in total CD4 cells. Increased numbers of IL-4-producing allergen-specific T-helper cells were found in patients with milk allergy. In addition, Foxp3 was coexpressed with IL-4 in allergen-specific TH2 cells from patients. This coexpression was associated with lower Bcl-2 levels and could contribute to the phenotype and function of TH2 cells. Copyright © 2015 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

[A multicenter study of correlation between peripheral lymphocyte counts and CD(+)4T cell counts in HIV/AIDS patients].

PubMed

Xie, Jing; Qiu, Zhifeng; Han, Yang; Li, Yanling; Song, Xiaojing; Li, Taisheng

2015-02-01

To evaluate the accuracy of lymphocyte count as a surrogate for CD(+)4T cell count in treatment-naїve HIV-infected adults. A total of 2 013 HIV-infected patients were screened at 23 sites in China. CD(+)4T cell counts were measured by flow cytometry. Correlation between CD(+)4T cell count and peripheral lymphocyte count were analyzed by spearman coefficient. AUCROC were used to evaluate the performance of lymphocyte count as a surrogate for CD(+)4T cell count. The lymphocyte count and CD(+)4T cell count of these 2 013 patients were (1 600 ± 670) × 10(6)/L and (244 ± 148) × 10(6)/L respectively. CD(+)4T cell count were positively correlated with lymphocyte count (r = 0.482, P < 0.000 1). AUCROC of lymphocyte count as a surrogate for CD(+)4T cell counts of <100×10(6)/L, <200×10(6)/L and <350×10(6)/L were 0.790 (95%CI 0.761-0.818, P < 0.000 1), 0.733 (95%CI 0.710-0.755, P < 0.000 1) and 0.732 (95%CI 0.706-0.758, P < 0.000 1) respectively. Lymphocyte count could be considerad as a potential surrogate marker for CD(+)4T cell count in HIV/AIDS patients not having access to T cell subset test by flowcytometry.

Foxp3-dependent transformation of human primary CD4+ T lymphocytes by the retroviral protein tax.

PubMed

Chen, Li; Liu, Dan; Zhang, Yang; Zhang, Huan; Cheng, Hua

2015-10-23

The retroviral Tax proteins of human T cell leukemia virus type 1 and 2 (HTLV-1 and -2) are highly homologous viral transactivators. Both viral proteins can immortalize human primary CD4+ memory T cells, but when expressed alone they rarely transform T cells. In the present study, we found that the Tax proteins displayed a differential ability to immortalize human CD4+Foxp3+ T cells with characteristic expression of CTLA-4 and GITR. Because epidermal growth factor receptor (EGFR) was reportedly expressed and activated in a subset of CD4+Foxp3+ T cells, we introduced an activated EGFR into Tax-immortalized CD4+Foxp3+ T cells. We observed that these modified cells were grown independently of exogenous IL-2, correlating with a T cell transformation phenotype. In Tax-immortalized CD4+Foxp3- T cells, ectopic expression of Foxp3 was a prerequisite for Tax transformation of T cells. Accordingly, treatment of the transformed T cells with erlotinib, a selective inhibitor of EGFR, induced degradation of EGFR in lysosome, consequently causing T cell growth inhibition. Further, we identified autophagy as a crucial cellular survival pathway for the transformed T cells. Silencing key autophagy molecules including Beclin1, Atg5 and PI3 kinase class III (PI3KC3) resulted in drastic impairment of T cell growth. Our data, therefore, unveiled a previously unidentified role of Foxp3 in T cell transformation, providing a molecular basis for HTLV-1 transformation of CD4+Foxp3+ T cells. Copyright © 2015 Elsevier Inc. All rights reserved.

Foxp3-dependent Transformation of Human Primary CD4+ T Lymphocytes by the Retroviral Protein Tax

PubMed Central

Chen, Li; Liu, Dan; Zhang, Yang; Zhang, Huan; Cheng, Hua

2015-01-01

The retroviral Tax proteins of human T cell leukemia virus type 1 and 2 (HTLV-1 and -2) are highly homologous viral transactivators. Both viral proteins can immortalize human primary CD4+ memory T cells, but when expressed alone they rarely transform T cells. In the present study, we found that the Tax proteins displayed a differential ability to immortalize human CD4+Foxp3+ T cells with characteristic expression of CTLA-4 and GITR. Because epidermal growth factor receptor (EGFR) was reportedly expressed and activated in a subset of CD4+Foxp3+ T cells, we introduced an activated EGFR into Tax-immortalized CD4+Foxp3+ T cells. We observed that these modified cells were grown independently of exogenous IL-2, correlating with a T cell transformation phenotype. In Tax-immortalized CD4+Foxp3- T cells, ectopic expression of Foxp3 was a prerequisite for Tax transformation of T cells. Accordingly, treatment of the transformed T cells with erlotinib, a selective inhibitor of EGFR, induced degradation of EGFR in lysosome, consequently causing T cell growth inhibition. Further, we identified autophagy as a crucial cellular survival pathway for the transformed T cells. Silencing key autophagy molecules including Beclin1, Atg5 and PI3 kinase class III (PI3KC3) resulted in drastic impairment of T cell growth. Our data, therefore, unveiled a previously unidentified role of Foxp3 in T cell transformation, providing a molecular basis for HTLV-1 transformation of CD4+Foxp3+ T cells. PMID:26381169

Low expression of CD39+/CD45RA+ on regulatory T cells (Treg) cells in type 1 diabetic children in contrast to high expression of CD101+/CD129+ on Treg cells in children with coeliac disease

PubMed Central

Åkesson, K; Tompa, A; Rydén, A; Faresjö, M

2015-01-01

Type 1 diabetes (T1D) and coeliac disease are both characterized by an autoimmune feature. As T1D and coeliac disease share the same risk genes, patients risk subsequently developing the other disease. This study aimed to investigate the expression of T helper (Th), T cytotoxic (Tc) and regulatory T cells (Treg) in T1D and/or coeliac disease children in comparison to healthy children. Subgroups of T cells (Th : CD4+ or Tc : CD8+); naive (CD27+CD28+CD45RA+CCR7+), central memory (CD27+CD28+CD45RA−CCR7+), effector memory (early differentiated; CD27+CD28+CD45RA−CCR7− and late differentiated; CD27−CD28−CD45RA−CCR7−), terminally differentiated effector cells (TEMRA; CD27−CD28−CD45RA+CCR7−) and Treg (CD4+CD25+FOXP3+CD127−) cells, and their expression of CD39, CD45RA, CD101 and CD129, were studied by flow cytometry in T1D and/or coeliac disease children or without any of these diseases (reference group). Children diagnosed with both T1D and coeliac disease showed a higher percentage of TEMRA CD4+ cells (P < 0·05), but lower percentages of both early and late effector memory CD8+ cells (P < 0·05) compared to references. Children with exclusively T1D had lower median fluorescence intensity (MFI) of forkhead box protein 3 (FoxP3) (P < 0·05) and also a lower percentage of CD39+ and CD45RA+ within the Treg population (CD4+CD25+FOXP3+CD127−) (P < 0·05). Children with exclusively coeliac disease had a higher MFI of CD101 (P < 0·01), as well as a higher percentage of CD129+ (P < 0·05), in the CD4+CD25hi lymphocyte population, compared to references. In conclusion, children with combined T1D and coeliac disease have a higher percentage of differentiated CD4+ cells compared to CD8+ cells. T1D children show signs of low CD39+/CD45RA+ Treg cells that may indicate loss of suppressive function. Conversely, children with coeliac disease show signs of CD101+/CD129+ Treg cells that may indicate suppressor activity. PMID:25421756

Allograft dendritic cell p40 homodimers activate donor-reactive memory CD8+ T cells

PubMed Central

Tsuda, Hidetoshi; Su, Charles A.; Tanaka, Toshiaki; Ayasoufi, Katayoun; Min, Booki; Valujskikh, Anna; Fairchild, Robert L.

2018-01-01

Recipient endogenous memory T cells with donor reactivity pose an important barrier to successful transplantation and costimulatory blockade–induced graft tolerance. Longer ischemic storage times prior to organ transplantation increase early posttransplant inflammation and negatively impact early graft function and long-term graft outcome. Little is known about the mechanisms enhancing endogenous memory T cell activation to mediate tissue injury within the increased inflammatory environment of allografts subjected to prolonged cold ischemic storage (CIS). Endogenous memory CD4+ and CD8+ T cell activation is markedly increased within complete MHC-mismatched cardiac allografts subjected to prolonged versus minimal CIS, and the memory CD8+ T cells directly mediate CTLA-4Ig–resistant allograft rejection. Memory CD8+ T cell activation within allografts subjected to prolonged CIS requires memory CD4+ T cell stimulation of graft DCs to produce p40 homodimers, but not IL-12 p40/p35 heterodimers. Targeting p40 abrogates memory CD8+ T cell proliferation within the allografts and their ability to mediate CTLA-4Ig–resistant allograft rejection. These findings indicate a critical role for memory CD4+ T cell–graft DC interactions to increase the intensity of endogenous memory CD8+ T cell activation needed to mediate rejection of higher-risk allografts subjected to increased CIS. PMID:29467328

Blocking the recruitment of naive CD4+ T cells reverses immunosuppression in breast cancer

PubMed Central

Su, Shicheng; Liao, Jianyou; Liu, Jiang; Huang, Di; He, Chonghua; Chen, Fei; Yang, LinBing; Wu, Wei; Chen, Jianing; Lin, Ling; Zeng, Yunjie; Ouyang, Nengtai; Cui, Xiuying; Yao, Herui; Su, Fengxi; Huang, Jian-dong; Lieberman, Judy; Liu, Qiang; Song, Erwei

2017-01-01

The origin of tumor-infiltrating Tregs, critical mediators of tumor immunosuppression, is unclear. Here, we show that tumor-infiltrating naive CD4+ T cells and Tregs in human breast cancer have overlapping TCR repertoires, while hardly overlap with circulating Tregs, suggesting that intratumoral Tregs mainly develop from naive T cells in situ rather than from recruited Tregs. Furthermore, the abundance of naive CD4+ T cells and Tregs is closely correlated, both indicating poor prognosis for breast cancer patients. Naive CD4+ T cells adhere to tumor slices in proportion to the abundance of CCL18-producing macrophages. Moreover, adoptively transferred human naive CD4+ T cells infiltrate human breast cancer orthotopic xenografts in a CCL18-dependent manner. In human breast cancer xenografts in humanized mice, blocking the recruitment of naive CD4+ T cells into tumor by knocking down the expression of PITPNM3, a CCL18 receptor, significantly reduces intratumoral Tregs and inhibits tumor progression. These findings suggest that breast tumor-infiltrating Tregs arise from chemotaxis of circulating naive CD4+ T cells that differentiate into Tregs in situ. Inhibiting naive CD4+ T cell recruitment into tumors by interfering with PITPNM3 recognition of CCL18 may be an attractive strategy for anticancer immunotherapy. PMID:28290464

T cells in chronic lymphocytic leukemia display dysregulated expression of immune checkpoints and activation markers.

PubMed

Palma, Marzia; Gentilcore, Giusy; Heimersson, Kia; Mozaffari, Fariba; Näsman-Glaser, Barbro; Young, Emma; Rosenquist, Richard; Hansson, Lotta; Österborg, Anders; Mellstedt, Håkan

2017-03-01

Chronic lymphocytic leukemia is characterized by impaired immune functions largely due to profound T-cell defects. T-cell functions also depend on co-signaling receptors, inhibitory or stimulatory, known as immune checkpoints, including cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and programmed death-1 (PD-1). Here we analyzed the T-cell phenotype focusing on immune checkpoints and activation markers in chronic lymphocytic leukemia patients (n=80) with different clinical characteristics and compared them to healthy controls. In general, patients had higher absolute numbers of CD3 + cells and the CD8 + subset was particularly expanded in previously treated patients. Progressive patients had higher numbers of CD4 + and CD8 + cells expressing PD-1 compared to healthy controls, which was more pronounced in previously treated patients ( P =0.0003 and P =0.001, respectively). A significant increase in antigen-experienced T cells was observed in patients within both the CD4 + and CD8 + subsets, with a significantly higher PD-1 expression. Higher numbers of CD4 + and CD8 + cells with intracellular CTLA-4 were observed in patients, as well as high numbers of proliferating (Ki67 + ) and activated (CD69 + ) CD4 + and CD8 + cells, more pronounced in patients with active disease. The numbers of Th1, Th2, Th17 and regulatory T cells were substantially increased in patients compared to controls ( P <0.05), albeit decreasing to low levels in pre-treated patients. In conclusion, chronic lymphocytic leukemia T cells display increased expression of immune checkpoints, abnormal subset distribution, and a higher proportion of proliferating cells compared to healthy T cells. Disease activity and previous treatment shape the T-cell profile of chronic lymphocytic leukemia patients in different ways. Copyright© Ferrata Storti Foundation.

Psychosocial factors and T lymphocyte counts in Brazilian peacekeepers.

PubMed

Silva, Angela M Monteiro da; Speranza, Francisco A B; Ishii, Solange Kiyoko; Hirata, Raphael; Mattos-Guaraldi, Ana Luíza; Milagres, Lucimar Gonçalves

2015-02-01

To investigate the associations between psychosocial factors and peripheral blood CD4 and CD8 T lymphocyte numbers in Brazilian peacekeepers. Venous blood was collected from 759 peacekeepers who had just returned from a peace mission in Haiti. Among the 759 soldiers, 642 individuals completed the psychosocial measures. CD4 and CD8 T lymphocyte counts were measured by flow cytometry using a commercially available kit. Psychosocial factors, including military peace force stressors, clinical stress, anxiety and depression, were recorded. As a reference for T lymphocyte numbers, we measured T lymphocyte counts in 75 blood donors from the Instituto de Biologia do Exército, Rio de Janeiro. The median numbers of CD4 and CD8 T lymphocytes in the blood donors were 819 cells/µl and 496 cells/µl, respectively, with a CD4:CD8 ratio of 1.6. Significantly (p<0.05) lower CD4 T cell counts (759 cells/µl) were recorded for peacekeepers, with similar CD8 levels (548 cells/µl) and smaller CD4:CD8 ratios (1.3, p<0.001) compared to blood donors. These differences were due to a group of 14 military personnel with CD4 and CD8 medians of 308 and 266 cells/µl, respectively. Only one (7.1%) of these 14 individuals was diagnosed with clinical stress compared with 13.5% of the individuals with normal levels of CD4 T lymphocytes. One individual out of 628 (0.16%) had a Lipp's Stress Symptom Inventory score of 3, indicating near exhaustion. The prevalence of psychological disorders was low and there were no associations with CD4 or CD8 T cell numbers.

Psychosocial factors and T lymphocyte counts in Brazilian peacekeepers

PubMed Central

Monteiro da Silva, Angela M; Speranza, Francisco A B; Ishii, Solange Kiyoko; Hirata, Raphael; Mattos-Guaraldi, Ana Luíza; Milagres, Lucimar Gonçalves

2015-01-01

OBJECTIVE: To investigate the associations between psychosocial factors and peripheral blood CD4 and CD8 T lymphocyte numbers in Brazilian peacekeepers. METHODS: Venous blood was collected from 759 peacekeepers who had just returned from a peace mission in Haiti. Among the 759 soldiers, 642 individuals completed the psychosocial measures. CD4 and CD8 T lymphocyte counts were measured by flow cytometry using a commercially available kit. Psychosocial factors, including military peace force stressors, clinical stress, anxiety and depression, were recorded. As a reference for T lymphocyte numbers, we measured T lymphocyte counts in 75 blood donors from the Instituto de Biologia do Exército, Rio de Janeiro. RESULTS: The median numbers of CD4 and CD8 T lymphocytes in the blood donors were 819 cells/µl and 496 cells/µl, respectively, with a CD4:CD8 ratio of 1.6. Significantly (p<0.05) lower CD4 T cell counts (759 cells/µl) were recorded for peacekeepers, with similar CD8 levels (548 cells/µl) and smaller CD4:CD8 ratios (1.3, p<0.001) compared to blood donors. These differences were due to a group of 14 military personnel with CD4 and CD8 medians of 308 and 266 cells/µl, respectively. Only one (7.1%) of these 14 individuals was diagnosed with clinical stress compared with 13.5% of the individuals with normal levels of CD4 T lymphocytes. One individual out of 628 (0.16%) had a Lipp's Stress Symptom Inventory score of 3, indicating near exhaustion. CONCLUSION: The prevalence of psychological disorders was low and there were no associations with CD4 or CD8 T cell numbers. PMID:25789525

Differential activation of human T cells to allogeneic endothelial cells, epithelial cells and fibroblasts in vitro

PubMed Central

2012-01-01

Background In the direct pathway, T cells recognize intact donor major histocompatability complexes and allogeneic peptide on the surface of donor antigen presenting cells (APCs). Indirect allorecognition results from the recognition of processed alloantigen by self MHC complexes on self APCs. In this study, we wished to evaluate the relative contribution of different intragraft cells to the alloactivation of nave and memory T cells though the direct and the indirect pathway of allorecognition. Methods The processing of membrane fragments from IFN-treated single donor endothelial cells (EC), fibroblasts or renal epithelial cells (RPTEC) was evaluated by DiOC labeling of each cell type and flow cytometry following interaction with PBMC. Direct pathway activation of nave CD45RA+ or memory CD45RO+ CD4+ T cells was evaluated following coculture with IFN-treated and MHC class II-expressing EC, fibroblasts or RPTEC. Indirect pathway activation was assessed using CD45RA+ or CD45RO+ CD4+ T cells cocultured with autologous irradiated APCs in the absence or presence of sonicates derived from IFN-treated allogeneic EC, fibroblasts or RPTEC. Activation of T cells was assessed by [3H]thymidine incorporation and by ELISpot assays. Results We find that CD14+ APCs readily acquire membrane fragments from fibroblasts and RPTEC, but fail to acquire membrane fragments from intact EC. However, APCs process membranes from EC undergoing apoptosis.There was a notable direct pathway alloproliferative response of CD45RO+ CD4+ T cells to IFN-treated EC, but not to fibroblasts or RPTEC. Also, there was a minimal direct pathway response of CD45RA+ CD4+ T cells to all cell types. In contrast, we found that both CD45RA+ and CD45RO+ CD4+ T cells proliferated following coculture with autologous APCs in the presence of sonicates derived from IFN-treated EC, fibroblasts or RPTEC. By ELISpot, we found that these T cells stimulated via the indirect pathway also produced the cytokines IFN, IL-2, IL-4 and IL-5. Conclusions Recipient APCs may readily process membrane fragments from allogeneic intragraft cells, but not from EC unless they are undergoing apoptosis. This processing is sufficient for indirect pathway alloactivation of both CD45RA+ and CD45RO+ CD4+ T cells. Only graft vascular EC mediate direct pathway reactivation of CD4+ T cells. PMID:23369287

Cutting Edge: 2B4-Mediated Coinhibition of CD4+ T Cells Underlies Mortality in Experimental Sepsis.

PubMed

Chen, Ching-Wen; Mittal, Rohit; Klingensmith, Nathan J; Burd, Eileen M; Terhorst, Cox; Martin, Greg S; Coopersmith, Craig M; Ford, Mandy L

2017-09-15

Sepsis is a leading cause of death in the United States, but the mechanisms underlying sepsis-induced immune dysregulation remain poorly understood. 2B4 (CD244, SLAM4) is a cosignaling molecule expressed predominantly on NK cells and memory CD8 + T cells that has been shown to regulate T cell function in models of viral infection and autoimmunity. In this article, we show that 2B4 signaling mediates sepsis lymphocyte dysfunction and mortality. 2B4 expression is increased on CD4 + T cells in septic animals and human patients at early time points. Importantly, genetic loss or pharmacologic inhibition of 2B4 significantly increased survival in a murine cecal ligation and puncture model. Further, CD4-specific conditional knockouts showed that 2B4 functions on CD4 + T cell populations in a cell-intrinsic manner and modulates adaptive and innate immune responses during sepsis. Our results illuminate a novel role for 2B4 coinhibitory signaling on CD4 + T cells in mediating immune dysregulation. Copyright © 2017 by The American Association of Immunologists, Inc.

TGF-β induces surface LAP expression on murine CD4 T cells independent of Foxp3 induction.

PubMed

Oida, Takatoku; Weiner, Howard L

2010-11-24

It has been reported that human FOXP3(+) CD4 Tregs express GARP-anchored surface latency-associated peptide (LAP) after activation, based on the use of an anti-human LAP mAb. Murine CD4 Foxp3(+) Tregs have also been reported to express surface LAP, but these studies have been hampered by the lack of suitable anti-mouse LAP mAbs. We generated anti-mouse LAP mAbs by immunizing TGF-β(-/-) animals with a mouse Tgfb1-transduced P3U1 cell line. Using these antibodies, we demonstrated that murine Foxp3(+) CD4 Tregs express LAP on their surface. In addition, retroviral transduction of Foxp3 into mouse CD4(+)CD25(-) T cells induced surface LAP expression. We then examined surface LAP expression after treating CD4(+)CD25(-) T cells with TGF-β and found that TGF-β induced surface LAP not only on T cells that became Foxp3(+) but also on T cells that remained Foxp3(-) after TGF-β treatment. GARP expression correlated with the surface LAP expression, suggesting that surface LAP is GARP-anchored also in murine T cells. Unlike human CD4 T cells, surface LAP expression on mouse CD4 T cells is controlled by Foxp3 and TGF-β. Our newly described anti-mouse LAP mAbs will provide a useful tool for the investigation and functional analysis of T cells that express LAP on their surface.

Expression of tyrosine hydroxylase in CD4+ T cells contributes to alleviation of Th17/Treg imbalance in collagen-induced arthritis.

PubMed

Wang, Xiao-Qin; Liu, Yan; Cai, Huan-Huan; Peng, Yu-Ping; Qiu, Yi-Hua

2016-12-01

Tyrosine hydroxylase (TH), a rate-limiting enzyme for the synthesis of catecholamines, is expressed in T lymphocytes. However, the role of T cell-expressed TH in rheumatoid arthritis (RA) is less clear. Herein, we aimed to show the contribution of TH expression by CD4 + T cells to alleviation of helper T (Th)17/regulatory T (Treg) imbalance in collagen-induced arthritis (CIA), a mouse model of RA. CIA was prepared by intradermal injection of collagen type II (CII) at tail base of DBA1/J mice. Expression of TH in the spleen and the ankle joints was measured by real-time polymerase chain reaction and Western blot analysis. Percentages of TH-expressing Th17 and Treg cells in splenic CD4 + T cells were determined by flow cytometry. Overexpression and knockdown of TH gene in CD4 + T cells were taken to evaluate effects of TH on Th17 and Treg cells in CIA. TH expression was upregulated in both the inflamed tissues (spleen and ankle joints) and the CD4 + T cells of CIA mice. In splenic CD4 + T cells, the cells expressing TH were increased during CIA. These cells that expressed more TH in CIA were mainly Th17 cells rather than Treg cells. TH gene overexpression in CD4 + T cells from CIA mice reduced Th17 cell percentage as well as Th17-related transcription factor and cytokine expression and secretion, whereas TH gene knockdown enhanced the Th17 cell activity. In contrast, TH gene overexpression increased Treg-related cytokine expression and secretion in CD4 + T cells of CIA mice, while TH gene knockdown decreased the Treg cell changes. Collectively, these findings show that CIA induces TH expression in CD4 + T cells, particularly in Th17 cells, and suggest that the increased TH expression during CIA represents an anti-inflammatory mechanism.

Pivotal Advance: Heme oxygenase 1 expression by human CD4+ T cells is not sufficient for their development of immunoregulatory capacity.

PubMed

Biburger, Markus; Theiner, Gabi; Schädle, Mirjam; Schuler, Gerold; Tiegs, Gisa

2010-02-01

HO-1 is the only inducible one of three isoenzymes that catalyzes the oxidative degradation of heme. HO-1 is inducible by various cellular stress factors and exerts cytoprotective and immunomodulatory effects. Recent publications demonstrated that HO-1 is constitutively expressed by CD4(+)CD25(+) T(regs) and induced in CD4(+)CD25(-) T cells upon FoxP3 transfection. Here, we investigated whether HO-1 was essential and sufficient for human T(regs) to exert immunosuppression in vitro. PGJ(2) induced pronounced expression of HO-1 in CD4(+)CD25(-) T cells without accompanying FoxP3 induction. Treatment of CD4(+)CD25(-) T cells with PGJ(2) decreased their proliferation, whereas the HO-1 inhibitor SnPP enhanced the proliferation of HO-1-expressing T(regs), suggesting that HO-1 may modulate the proliferative capacity of T lymphocytes. HO-1 modulation by SnPP treatment of T(regs) or PGJ(2) treatment of CD4(+)CD25(-) T cells neither suppressed nor induced immune-modulatory function in these cells, respectively, as measured by responder-cell proliferation and/or IL-2 production. In summary, these data suggest that HO-1 expression by T(regs) might contribute to their typical reluctance to proliferate but does not account independently for their suppressive functions.

Minimally Activated CD8 Autoreactive T Cells Specific for IRBP Express a High Level of Foxp3 and Are Functionally Suppressive

PubMed Central

Peng, Yong; Shao, Hui; Ke, Yan; Zhang, Ping; Han, Gencheng; Kaplan, Henry J.; Sun, Deming

2008-01-01

Purpose Results in previous reports have demonstrated that immunization of the EAU-prone B6 mouse activates both CD4 and CD8 IRBP-specific T cells. The purpose of this study was to investigate structural and functional differences between CD4 and CD8 autoreactive T cells activated by the uveitogenic peptide. Methods Purified CD4 and CD8 isolated from B6 mice immunized with an uveitogenic peptide, interphotoreceptor retin-oid-binding protein (IRBP)1-20, were stimulated in vitro with various doses of immunizing peptide. The activated T cells were determined for cytokine production, expression of Foxp3, and suppressor activity. Results CD4 autoreactive T cells underwent full activation when stimulated with high or medium concentrations of immunizing peptide, whereas a high dose of antigenic peptide resulted in only modest activation of CD8 autoreactive T cells. When stimulated by a low dose (<0.1 μg/mL) of antigen or by of a high dose of antigen and a small amount of TGF-β1, the minimally activated CD8 T cells expressed a high level of Foxp3 and gained suppressor function. Conclusions Minimally activated CD8 autoreactive T cells can be functionally suppressive and may neutralize the tissue-damaging effect of the CD4 autoreactive T cells. PMID:17460277

FOXP3-expressing CD4(+) T-cell numbers increase in areas of duodenal gastric metaplasia and are associated to CD4(+) T-cell aggregates in the duodenum of Helicobacter pylori-infected duodenal ulcer patients.

PubMed

Kindlund, Bert; Sjöling, Asa; Hansson, Malin; Edebo, Anders; Hansson, Lars-Erik; Sjövall, Henrik; Svennerholm, Ann-Mari; Lundin, B Samuel

2009-06-01

We have previously demonstrated that Helicobacter pylori infection is associated with an increased number of CD4(+)CD25(high) regulatory T cells in the gastric and duodenal mucosa. In this study, we determined the number and localization of CD4(+) cells expressing the regulatory T-cell-specific transcription factor FOXP3 in the antrum and duodenum of duodenal ulcer patients, asymptomatic carriers, and uninfected individuals. We also determined gene expression levels of FOXP3 as well as anti- and proinflammatory cytokines before and after H. pylori eradication. Cellular FOXP3 expression was studied by immunofluorescence and flow cytometry, and transcription levels of FOXP3, interleukin (IL)-10, transforming growth factor-beta, CD4, and interferon-gamma were analyzed by real-time reverse transcription-polymerase chain reaction. We found an increased (6-fold) frequency of CD4(+)FOXP3(+) T cells in H. pylori-infected gastric mucosa; interestingly 26% of these cells did not co-express CD25. The increase of FOXP3-expressing T cells in the antrum of infected individuals was dependent on the presence of H. pylori, since eradication therapy resulted in 4-fold lower levels of FOXP3 and IL-10 mRNA in the antrum. Furthermore, higher numbers of CD4(+)FOXP3(+) T cells were found in areas of duodenal gastric metaplasia in the duodenum of duodenal ulcer patients compared to duodenal gastric metaplasia of asymptomatic individuals and healthy mucosa in both patient groups. In duodenal ulcer patients, the CD4(+)FOXP3(+) T cells were more highly associated to aggregates in the duodenal mucosa. The numbers of CD4(+)FOXP3(+) T cells are increased and localized in CD4(+) T-cell aggregates in areas of duodenal gastric metaplasia in duodenal ulcer patients.

Split T Cell Tolerance against a Self/Tumor Antigen: Spontaneous CD4+ but Not CD8+ T Cell Responses against p53 in Cancer Patients and Healthy Donors

PubMed Central

Tsuji, Takemasa; Matsuzaki, Junko; Ritter, Erika; Miliotto, Anthony; Ritter, Gerd; Odunsi, Kunle; Old, Lloyd J.; Gnjatic, Sacha

2011-01-01

Analyses of NY-ESO-1-specific spontaneous immune responses in cancer patients revealed that antibody and both CD4+ and CD8+ T cell responses were induced together in cancer patients. To explore whether such integrated immune responses are also spontaneously induced for other tumor antigens, we have evaluated antibody and T cell responses against self/tumor antigen p53 in ovarian cancer patients and healthy individuals. We found that 21% (64/298) of ovarian cancer patients but no healthy donors showed specific IgG responses against wild-type p53 protein. While none of 12 patients with high titer p53 antibody showed spontaneous p53-specific CD8+ T cell responses following a single in vitro sensitization, significant p53-specific IFN-γ producing CD4+ T cells were detected in 6 patients. Surprisingly, similar levels of p53-specific CD4+ T cells but not CD8+ T cells were also detected in 5/10 seronegative cancer patients and 9/12 healthy donors. Importantly, p53-specific CD4+ T cells in healthy donors originated from a CD45RA− antigen-experienced T cell population and recognized naturally processed wild-type p53 protein. These results raise the possibility that p53-specific CD4+ T cells reflect abnormalities in p53 occurring in normal individuals and that they may play a role in processes of immunosurveillance or immunoregulation of p53-related neoplastic events. PMID:21858191

Low Antigen Dose in Adjuvant-Based Vaccination Selectively Induces CD4 T Cells with Enhanced Functional Avidity and Protective Efficacy

PubMed Central

Wang, Yichuan; Solaymani-Mohammadi, Shahram; Frey, Blake; Kulkarni, Shweta; Andersen, Peter; Agger, Else Marie; Sui, Yongjun

2017-01-01

T cells with high functional avidity can sense and respond to low levels of cognate Ag, a characteristic that is associated with more potent responses against tumors and many infections, including HIV. Although an important determinant of T cell efficacy, it has proven difficult to selectively induce T cells of high functional avidity through vaccination. Attempts to induce high-avidity T cells by low-dose in vivo vaccination failed because this strategy simply gave no response. Instead, selective induction of high-avidity T cells has required in vitro culturing of specific T cells with low Ag concentrations. In this study, we combined low vaccine Ag doses with a novel potent cationic liposomal adjuvant, cationic adjuvant formulation 09, consisting of dimethyldioctadecylammonium liposomes incorporating two immunomodulators (monomycolyl glycerol analog and polyinosinic-polycytidylic acid) that efficiently induces CD4 Th cells, as well as cross-primes CD8 CTL responses. We show that vaccination with low Ag dose selectively primes CD4 T cells of higher functional avidity, whereas CD8 T cell functional avidity was unrelated to vaccine dose in mice. Importantly, CD4 T cells of higher functional avidity induced by low-dose vaccinations showed higher cytokine release per cell and lower inhibitory receptor expression (PD-1, CTLA-4, and the apoptosis-inducing Fas death receptor) compared with their lower-avidity CD4 counterparts. Notably, increased functional CD4 T cell avidity improved antiviral efficacy of CD8 T cells. These data suggest that potent adjuvants, such as cationic adjuvant formulation 09, render low-dose vaccination a feasible and promising approach for generating high-avidity T cells through vaccination. PMID:28348274

PKM2-dependent metabolic reprogramming in CD4+ T cells is crucial for hyperhomocysteinemia-accelerated atherosclerosis.

PubMed

Lü, Silin; Deng, Jiacheng; Liu, Huiying; Liu, Bo; Yang, Juan; Miao, Yutong; Li, Jing; Wang, Nan; Jiang, Changtao; Xu, Qingbo; Wang, Xian; Feng, Juan

2018-06-01

Inflammation mediated by activated T cells plays an important role in the initiation and progression of hyperhomocysteinemia (HHcy)-accelerated atherosclerosis in ApoE -/- mice. Homocysteine (Hcy) activates T cells to secrete proinflammatory cytokines, especially interferon (IFN)-γ; however, the precise mechanisms remain unclear. Metabolic reprogramming is critical for T cell inflammatory activation and effector functions. Our previous study demonstrated that Hcy regulates T cell mitochondrial reprogramming by enhancing endoplasmic reticulum (ER)-mitochondria coupling. In this study, we further explored the important role of glycolysis-mediated metabolic reprogramming in Hcy-activated CD4 + T cells. Mechanistically, Hcy-activated CD4 + T cell increased the protein expression and activity of pyruvate kinase muscle isozyme 2 (PKM2), the final rate-limiting enzyme in glycolysis, via the phosphatidylinositol 3-kinase/AKT/mechanistic target of rapamycin signaling pathway. Knockdown of PKM2 by small interfering RNA reduced Hcy-induced CD4 + T cell IFN-γ secretion. Furthermore, we generated T cell-specific PKM2 knockout mice by crossing LckCre transgenic mice with PKM2 fl/fl mice and observed that Hcy-induced glycolysis and oxidative phosphorylation were both diminished in PKM2-deficient CD4 + T cells with reduced glucose and lipid metabolites, and subsequently reduced IFN-γ secretion. T cell-depleted apolipoprotein E-deficient (ApoE -/- ) mice adoptively transferred with PKM2-deficient CD4 + T cells, compared to mice transferred with control cells, showed significantly decreased HHcy-accelerated early atherosclerotic lesion formation. In conclusion, this work indicates that the PKM2-dependent glycolytic-lipogenic axis, a novel mechanism of metabolic regulation, is crucial for HHcy-induced CD4 + T cell activation to accelerate early atherosclerosis in ApoE -/- mice. Metabolic reprogramming is crucial for Hcy-induced CD4 + T cell inflammatory activation. Hcy activates the glycolytic-lipogenic pathway in CD4 + T cells via PKM2. Targeting PKM2 attenuated HHcy-accelerated early atherosclerosis in ApoE -/- mice in vivo.

CD4 T cells promote rather than control tuberculosis in the absence of PD-1-mediated inhibition.

PubMed

Barber, Daniel L; Mayer-Barber, Katrin D; Feng, Carl G; Sharpe, Arlene H; Sher, Alan

2011-02-01

Although CD4 T cells are required for host resistance to Mycobacterium tuberculosis, they may also contribute to pathology. In this study, we examine the role of the inhibitory receptor PD-1 and its ligand PD-L1 during M. tuberculosis infection. After aerosol exposure, PD-1 knockout (KO) mice develop high numbers of M. tuberculosis-specific CD4 T cells but display markedly increased susceptibility to infection. Importantly, we show that CD4 T cells themselves drive the increased bacterial loads and pathology seen in infected PD-1 KO mice, and PD-1 deficiency in CD4 T cells is sufficient to trigger early mortality. PD-L1 KO mice also display enhanced albeit less severe susceptibility, indicating that T cells are regulated by multiple PD ligands during M. tuberculosis infection. M. tuberculosis-specific CD8 T cell responses were normal in PD-1 KO mice, and CD8 T cells only had a minor contribution to the exacerbated disease in the M. tuberculosis-infected PD-1 KO and PD-L1 KO mice. Thus, in the absence of the PD-1 pathway, M. tuberculosis benefits from CD4 T cell responses, and host resistance requires inhibition by PD-1 to prevent T cell-driven exacerbation of the infection.

A short CD3/CD28 costimulation combined with IL-21 enhance the generation of human memory stem T cells for adoptive immunotherapy.

PubMed

Alvarez-Fernández, C; Escribà-Garcia, L; Vidal, S; Sierra, J; Briones, J

2016-07-19

Immunotherapy based on the adoptive transfer of gene modified T cells is an emerging approach for the induction of tumor-specific immune responses. Memory stem T cells, due to their enhanced antitumor and self-renewal capacity, have become potential candidate for adoptive T cell therapy of cancer. Methods to generate memory stem T cells ex vivo rely on CD3/CD28 costimulation and the use of cytokines such as IL-7 and IL-15 during the entire culture period. However, a strong costimulation may induce differentiation of memory stem T cells to effector memory T cells. Here we show that manipulation of the length of the costimulation and addition of IL-21 enhance the ex vivo expansion of memory stem T cells. Purified naïve T cells from healthy donors were cultured in the presence of anti-CD3/CD28 coated beads, IL-7, IL-15 and/or IL-21 (25 ng/ml). T cells phenotype from the different memory and effector subpopulations were analyzed by multiparametric flow cytometry. A short anti-CD3/CD28 costimulation of naïve T cells, combined with IL-7 and IL-15 significantly increased the frequencies of CD4(+) and CD8(+) memory stem T cells ex vivo, compared to a prolonged costimulation (34.6 ± 4.4 % vs 15.6 ± 4.24 % in CD4(+); p = 0.008, and 20.5 ± 4.00 % vs 7.7 ± 2.53 % in CD8(+); p = 0.02). Moreover, the addition of IL-21 to this condition further enhanced the enrichment and expansion of CD4(+) and CD8(+) memory stem T cells with an increase in the absolute numbers (0.7 × 10(6) ± 0.1 vs 0.26 × 10(6) ± 0.1 cells for CD4(+); p = 0.002 and 1.1 × 10(6) ± 0.1 vs 0.27 × 10(6) ± 0.1 cells for CD8(+); p = 0.0002; short + IL-21 vs long). These new in vitro conditions increase the frequencies and expansion of memory stem T cells and may have relevant clinical implications for the generation of this memory T cell subset for adoptive cell therapy of patients with cancer.

CD4+ T cells are important mediators of oxidative stress that cause hypertension in response to placental ischemia.

PubMed

Wallace, Kedra; Cornelius, Denise C; Scott, Jeremy; Heath, Judith; Moseley, Janae; Chatman, Krystal; LaMarca, Babbette

2014-11-01

Preeclampsia is associated with oxidative stress, which is suspected to play a role in hypertension, placental ischemia, and fetal demise associated with the disease. Various cellular sources of oxidative stress, such as neutrophils, monocytes, and CD4(+) T cells have been suggested as culprits in the pathophysiology of preeclampsia. The objective of this study was to examine a role of circulating and placental CD4(+) T cells in oxidative stress in response to placental ischemia during pregnancy. CD4(+) T cells and oxidative stress were measured in preeclamptic and normal pregnant women, placental ischemic and normal pregnant rats, and normal pregnant recipient rats of placental ischemic CD4(+) T cells. Women with preeclampsia had significantly increased circulating (P=0.02) and placental CD4(+) T cells (P=0.0001); lymphocyte secretion of myeloperoxidase (P=0.004); and placental reactive oxygen species (P=0.0004) when compared with normal pregnant women. CD4(+) T cells from placental ischemic rats cause many facets of preeclampsia when injected into normal pregnant recipient rats on gestational day 13. On gestational day 19, blood pressure increased in normal pregnant recipients of placental ischemic CD4(+) T cells (P=0.002) compared with that in normal pregnant rats. Similar to preeclamptic patients, CD4(+) T cells from placental ischemic rats secreted significantly more myeloperoxidase (P=0.003) and induced oxidative stress in cultured vascular cells (P=0.003) than normal pregnant rat CD4(+)Tcells. Apocynin, a nicotinamide adenine dinucleotide phosphate inhibitor, attenuated hypertension and all oxidative stress markers in placental ischemic and normal pregnant recipient rats of placental ischemic CD4(+)Tcells (P=0.05). These data demonstrate an important role for CD4(+) T cells in mediating another factor, oxidative stress, to cause hypertension during preeclampsia. © 2014 American Heart Association, Inc.

HIV Controllers Exhibit Enhanced Frequencies of Major Histocompatibility Complex Class II Tetramer+ Gag-Specific CD4+ T Cells in Chronic Clade C HIV-1 Infection

PubMed Central

Laher, Faatima; Ranasinghe, Srinika; Porichis, Filippos; Mewalal, Nikoshia; Pretorius, Karyn; Ismail, Nasreen; Buus, Søren; Stryhn, Anette; Carrington, Mary; Walker, Bruce D.; Ndung'u, Thumbi

2017-01-01

ABSTRACT Immune control of viral infections is heavily dependent on helper CD4+ T cell function. However, the understanding of the contribution of HIV-specific CD4+ T cell responses to immune protection against HIV-1, particularly in clade C infection, remains incomplete. Recently, major histocompatibility complex (MHC) class II tetramers have emerged as a powerful tool for interrogating antigen-specific CD4+ T cells without relying on effector functions. Here, we defined the MHC class II alleles for immunodominant Gag CD4+ T cell epitopes in clade C virus infection, constructed MHC class II tetramers, and then used these to define the magnitude, function, and relation to the viral load of HIV-specific CD4+ T cell responses in a cohort of untreated HIV clade C-infected persons. We observed significantly higher frequencies of MHC class II tetramer-positive CD4+ T cells in HIV controllers than progressors (P = 0.0001), and these expanded Gag-specific CD4+ T cells in HIV controllers showed higher levels of expression of the cytolytic proteins granzymes A and B. Importantly, targeting of the immunodominant Gag41 peptide in the context of HLA class II DRB1*1101 was associated with HIV control (r = −0.5, P = 0.02). These data identify an association between HIV-specific CD4+ T cell targeting of immunodominant Gag epitopes and immune control, particularly the contribution of a single class II MHC-peptide complex to the immune response against HIV-1 infection. Furthermore, these results highlight the advantage of the use of class II tetramers in evaluating HIV-specific CD4+ T cell responses in natural infections. IMPORTANCE Increasing evidence suggests that virus-specific CD4+ T cells contribute to the immune-mediated control of clade B HIV-1 infection, yet there remains a relative paucity of data regarding the role of HIV-specific CD4+ T cells in shaping adaptive immune responses in individuals infected with clade C, which is responsible for the majority of HIV infections worldwide. Understanding the contribution of HIV-specific CD4+ T cell responses in clade C infection is particularly important for developing vaccines that would be efficacious in sub-Saharan Africa, where clade C infection is dominant. Here, we employed MHC class II tetramers designed to immunodominant Gag epitopes and used them to characterize CD4+ T cell responses in HIV-1 clade C infection. Our results demonstrate an association between the frequency of HIV-specific CD4+ T cell responses targeting an immunodominant DRB1*11-Gag41 complex and HIV control, highlighting the important contribution of a single class II MHC-peptide complex to the immune response against HIV-1 infections. PMID:28077659

Acid sphingomyelinase mediates human CD4+ T-cell signaling: potential roles in T-cell responses and diseases

PubMed Central

Bai, Aiping; Guo, Yuan

2017-01-01

Acid sphingomyelinase (ASM) is a lipid hydrolase. By generating ceramide, ASM had been reported to have an important role in regulating immune cell functions inclusive of macrophages, NK cells, and CD8+ T cells, whereas the role of ASM bioactivity in regulation of human CD4+ T-cell functions remained uncertain. Recent studies have provided novel findings in this field. Upon stimulation of CD3 and/or CD28, ASM-dependent ceramide signaling mediates intracellular downstream signal cascades of CD3 and CD28, and regulates CD4+ T-cell activation and proliferation. Meanwhile, CD39 and CD161 have direct interactions with ASM, which mediates downstream signals inclusive of STAT3 and mTOR and thus defines human Th17 cells. Intriguingly, ASM mediates Th1 responses, but negatively regulates Treg functions. In this review, we summarized the pivotal roles of ASM in regulation of human CD4+ T-cell activation and responses. ASM/sphingolipid signaling may be a novel target for the therapy of human autoimmune diseases. PMID:28749465

Cytokines and the regulation of fungus-specific CD4 T cell differentiation

PubMed Central

Espinosa, Vanessa; Rivera, Amariliz

2011-01-01

CD4 T cells play important and non-redundant roles in protection against infection with diverse fungi. Distinct CD4 T cell subsets can mediate protection against fungal disease where Th1 and Th17 CD4 T cell subsets have been found to promote fungal clearance and protective immunity against diverse fungal pathogens. The differentiation of naïve CD4 T cells into Th1 or Th17 cells is crucially controlled by their interaction with dendritic cells and instructed by cytokines. IL-12 and IFN-γ promote Th1 differentiation while TGF-β, IL-6, IL-1, IL-21 and IL-23 promote Th17 differentiation and maintenance. The production of these cytokines by DCs is in turn regulated by innate receptors triggered in response to fungal infection. In this review we will discuss the contributions of cytokines found to influence fungus-specific CD4 T cell differentiation and their role in defense against fungal disease. We will also highlight the contributions of innate receptors involved in recognition of fungi and how they shape cytokine secretion and CD4 T cell differentiation. PMID:22133343

CMV drives the expansion of highly functional memory T cells expressing NK-cell receptors in renal transplant recipients.

PubMed

Makwana, Nandini; Foley, Bree; Fernandez, Sonia; Lee, Silvia; Irish, Ashley; Pircher, Hanspeter; Price, Patricia

2017-08-01

Cytomegalovirus (CMV) is a common opportunistic infection encountered in renal transplant recipients (RTRs) and may be reactivated without symptoms at any time post-transplant. We describe how active and latent CMV affect T-cell subsets in RTRs who are stable on maintenance therapy. T-cell responses to CMV were assessed in RTRs (n = 54) >2 years post-transplant, and healthy controls (n = 38). Seven RTRs had CMV DNA detectable in plasma. CMV antibody and DNA aligned with increased proportions of CD8 + T cells and reduced CD4/CD8 ratios. This paralleled an expansion of effector memory T-cell (T EM ), terminally differentiated T-cell (T EMRA ) and CD57 + T EMRA cell populations. Expression of NK-cell receptors, LIR-1 and KLRG1 on CD4 + and CD8 + CD57 + T EM and T EMRA cells correlated with elevated interferon-γ and cytotoxic responses to anti-CD3 and increased cytotoxic responses to CMV phosphoprotein (pp) 65 in RTRs who carried CMV DNA. CD8 + T cells from all CMV seropositive RTRs responded efficiently to CMV immediate early (IE) -1 peptides. The data show that latent and active CMV infection can alter T-cell subsets in RTRs many years after transplantation, and up-regulate T-cell expression of NK-cell receptors. This may enhance effector responses of CD4 + and CD8 + T cells against CMV. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

OX62+OX6+OX35+ rat dendritic cells are unable to prime CD4+ T cells for an effective immune response following acute burn injury.

PubMed

Fazal, Nadeem

2013-01-01

Co-stimulatory molecules expressed on Dendritic Cells (DCs) function to coordinate an efficient immune response by T cells in the peripheral lymph nodes. We hypothesized that CD4+ T cell-mediated immune suppression following burn injury may be related to dysfunctional DCs residing in gut associated lymphoid tissues (GALT), such as Mesenteric Lymph Nodes (MLN). Therefore, we studied co-stimulatory molecules expressed on burn rat MLN DCs as an index of functional DCs that would mount an effective normal CD4+ T cell immune response. In a rat model of 30% Total Body Surface Area (TBSA) scald burn, OX62+OX6+OX35+ DCs and CD4+ T cells were isolated from MLN of day 3 post-burn and sham control rats. DCs were tested for their expression of co-stimulatory molecules, and prime CD4+ T cell (DC:CD4+T cell co-culture assays) to determine an effector immune response such as CD4+ T cell proliferation. The surface receptor expressions of MLN DCs co-stimulatory molecules, i.e., MHC-II, CD40, CD80 (B7-1), and CD86 (B7-2) were determined by Flow cytometry (quantitatively) and confocal microscopy (qualitatively). Tritiated thymidine and CFDA-SE determined CD4+ T cell proliferation following co-incubation with DCs. Cytokine milieu of MLN (IL-12 and IL-10) was assessed by mRNA determination by RT-PCR. The results showed down-regulated expressions of co-stimulatory markers (CD80, CD86, CD40 and MHC-II) of MLN DCs obtained from burn-injured rats, as well as lack of ability of these burn-induced DCs to stimulate CD4+ T cell proliferation in co-culture assays, as compared to the sham rats. Moreover, anti-CD40 stimulation of affected burn MLN DCs did not reverse this alteration. Furthermore, a marked up-regulation of mRNA IL-10 and down-regulation of mRNA IL-12 in burn MLN as compared to sham animals was also observed. To surmise, the data indicated that dysfunctional OX62+OX6+OX35+ rat MLN DCs may contribute to CD4+ T-cell-mediated immune suppression observed following acute burn injury.

OX62+OX6+OX35+ rat dendritic cells are unable to prime CD4+ T cells for an effective immune response following acute burn injury☆

PubMed Central

Fazal, Nadeem

2013-01-01

Co-stimulatory molecules expressed on Dendritic Cells (DCs) function to coordinate an efficient immune response by T cells in the peripheral lymph nodes. We hypothesized that CD4+ T cell-mediated immune suppression following burn injury may be related to dysfunctional DCs residing in gut associated lymphoid tissues (GALT), such as Mesenteric Lymph Nodes (MLN). Therefore, we studied co-stimulatory molecules expressed on burn rat MLN DCs as an index of functional DCs that would mount an effective normal CD4+ T cell immune response. In a rat model of 30% Total Body Surface Area (TBSA) scald burn, OX62+OX6+OX35+ DCs and CD4+ T cells were isolated from MLN of day 3 post-burn and sham control rats. DCs were tested for their expression of co-stimulatory molecules, and prime CD4+ T cell (DC:CD4+T cell co-culture assays) to determine an effector immune response such as CD4+ T cell proliferation. The surface receptor expressions of MLN DCs co-stimulatory molecules, i.e., MHC-II, CD40, CD80 (B7-1), and CD86 (B7-2) were determined by Flow cytometry (quantitatively) and confocal microscopy (qualitatively). Tritiated thymidine and CFDA-SE determined CD4+ T cell proliferation following co-incubation with DCs. Cytokine milieu of MLN (IL-12 and IL-10) was assessed by mRNA determination by RT-PCR. The results showed down-regulated expressions of co-stimulatory markers (CD80, CD86, CD40 and MHC-II) of MLN DCs obtained from burn-injured rats, as well as lack of ability of these burn-induced DCs to stimulate CD4+ T cell proliferation in co-culture assays, as compared to the sham rats. Moreover, anti-CD40 stimulation of affected burn MLN DCs did not reverse this alteration. Furthermore, a marked up-regulation of mRNA IL-10 and down-regulation of mRNA IL-12 in burn MLN as compared to sham animals was also observed. To surmise, the data indicated that dysfunctional OX62+OX6+OX35+ rat MLN DCs may contribute to CD4+ T-cell-mediated immune suppression observed following acute burn injury. PMID:24600560

FoxP3+CD4+CD25+ T cells with regulatory properties can be cultured from colonic mucosa of patients with Crohn's disease

PubMed Central

Kelsen, J; Agnholt, J; Hoffmann, H J; Rømer, J L; Hvas, C L; Dahlerup, J F

2005-01-01

CD4+CD25+ regulatory T cells (Tregs) are involved in the maintenance of peripheral tolerance and ensure a balanced immune response competent of fighting pathogens and at the same time recognizing commensals as harmless. This feature is lost in Crohn's disease (CD). The forkhead/winged helix transcription factor FoxP3 is a master gene for Treg function and defects in the FoxP3 gene lead to a clinical picture similar to inflammatory bowel disease (IBD). Murine colitis can be cured by adoptive transfer of Tregs and ex vivo-generated gut-specific Tregs represent an attractive option for therapy in CD. Thus, defective Tregs could contribute to the development of CD. We cultured biopsies of colonic mucosa in the presence of high concentrations of interleukin (IL)-2 and IL-4 to overcome the anergic nature of naturally occurring CD4+CD25+ Tregs in the mucosa. We investigated the expression of FoxP3 and regulatory potential of gut-derived CD4+CD25+ T cells cultured from patients with CD and healthy individuals. The FoxP3 expression was analysed by reverse transcriptase polymerase chain reaction (RT-PCR), and the suppressive effect of FoxP3+CD4+CD25+ T cells on proliferation and cytokine production of autologous CD4+ T cells was assessed by flow cytometry. Cultured gut-derived T cells with CD4+CD25+ phenotype expressed FoxP3 and were able as the freshly isolated Tregs from peripheral blood to suppress proliferation and cytokine production of autologous CD4+ T cells. Thus, we demonstrate that FoxP3+CD4+CD25+ T cells with regulatory properties can be propagated in vitro from inflamed mucosa of CD patients, which may be of interest in adoptive immunotherapy. PMID:16045746

CD26 expression and adenosine deaminase activity in regulatory T cells (Treg) and CD4+ T effector cells in patients with head and neck squamous cell carcinoma

PubMed Central

Mandapathil, Magis; Szczepanski, Miroslaw; Harasymczuk, Malgorzata; Ren, Jin; Cheng, Dongmei; Jackson, Edwin K.; Gorelik, Elieser; Johnson, Jonas; Lang, Stephan; Whiteside, Theresa L

2012-01-01

Adenosine deaminase (ADA) is responsible for the deamination of immunosuppressive adenosine to inosine. In human T lymphocytes, ADA is associated with dipeptidyl peptidase IV (CD26). ADA expression and activity were evaluated in regulatory T cells (Treg) and CD4+ T effector cells (Teff) of patients with head and neck squamous cell cancer (HNSCC). CD4+CD39+ and CD4+CD39neg T cells were isolated by single-cell sorting from the peripheral blood of 15 HNSCC patients and 15 healthy donors (NC). CD26/ADA expression in these cells was studied by multicolor flow cytometry, confocal microscopy, RT-PCR and immunohistochemistry in tumor tissues. ADA activity was evaluated by mass spectrometry, suppression of Teff proliferation in CFSE assays and cytokine production by Luminex. CD4+CD39+ Treg had low and CD4+CD39neg Teff high CD26/ADA expression and ADA activity in NC or HNSCC. The frequency and suppressor activity of CD39+CD26neg Treg were elevated in patients relative to NC (p < 0.01). However, ADA activity in patients’ CD4+CD39neg Teff was decreased (p < 0.05), resulting in extracellular adenosine accumulation. Also, patients’ Teff were more sensitive to inhibitory signals delivered via adenosine receptors. IL-2, IL12 and INFγ upregulated ADA expression and activity in CD4+CD39neg Teff, whereas IL-10, PGE2 and CADO downregulated it. The differentially expressed CD26/ADA can serve as surface markers for functionally-active CD39+CD26neg Treg. PMID:22934258

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

PubMed

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

2011-11-01

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

Roles of lymphatic endothelial cells expressing peripheral tissue antigens in CD4 T-cell tolerance induction.

PubMed

Rouhani, Sherin J; Eccles, Jacob D; Riccardi, Priscila; Peske, J David; Tewalt, Eric F; Cohen, Jarish N; Liblau, Roland; Mäkinen, Taija; Engelhard, Victor H

2015-04-10

Lymphatic endothelial cells (LECs) directly express peripheral tissue antigens and induce CD8 T-cell deletional tolerance. LECs express MHC-II molecules, suggesting they might also tolerize CD4 T cells. We demonstrate that when β-galactosidase (β-gal) is expressed in LECs, β-gal-specific CD8 T cells undergo deletion via the PD-1/PD-L1 and LAG-3/MHC-II pathways. In contrast, LECs do not present endogenous β-gal in the context of MHC-II molecules to β-gal-specific CD4 T cells. Lack of presentation is independent of antigen localization, as membrane-bound haemagglutinin and I-Eα are also not presented by MHC-II molecules. LECs express invariant chain and cathepsin L, but not H2-M, suggesting that they cannot load endogenous antigenic peptides onto MHC-II molecules. Importantly, LECs transfer β-gal to dendritic cells, which subsequently present it to induce CD4 T-cell anergy. Therefore, LECs serve as an antigen reservoir for CD4 T-cell tolerance, and MHC-II molecules on LECs are used to induce CD8 T-cell tolerance via LAG-3.

Roles of lymphatic endothelial cells expressing peripheral tissue antigens in CD4 T-cell tolerance induction

PubMed Central

Rouhani, Sherin J.; Eccles, Jacob D.; Riccardi, Priscila; Peske, J. David; Tewalt, Eric F.; Cohen, Jarish N.; Liblau, Roland; Mäkinen, Taija; Engelhard, Victor H.

2015-01-01

Lymphatic endothelial cells (LECs) directly express peripheral tissue antigens and induce CD8 T-cell deletional tolerance. LECs express MHC-II molecules, suggesting they might also tolerize CD4 T cells. We demonstrate that when β-galactosidase (β-gal) is expressed in LECs, β-gal-specific CD8 T cells undergo deletion via the PD-1/PD-L1 and LAG-3/MHC-II pathways. In contrast, LECs do not present endogenous β-gal in the context of MHC-II molecules to β-gal-specific CD4 T cells. Lack of presentation is independent of antigen localization, as membrane-bound haemagglutinin and I-Eα are also not presented by MHC-II molecules. LECs express invariant chain and cathepsin L, but not H2-M, suggesting that they cannot load endogenous antigenic peptides onto MHC-II molecules. Importantly, LECs transfer β-gal to dendritic cells, which subsequently present it to induce CD4 T-cell anergy. Therefore, LECs serve as an antigen reservoir for CD4 T-cell tolerance, and MHC-II molecules on LECs are used to induce CD8 T-cell tolerance via LAG-3. PMID:25857745

Cutting edge: the relative distribution of T cells responding to chemically dominant or minor epitopes of lysozyme is not affected by CD40-CD40 ligand and B7-CD28-CTLA-4 costimulatory pathways.

PubMed

DiPaolo, Richard J; Unanue, Emil R

2002-09-15

We examined the frequencies and specificities of the CD4+ T cell responses to the protein hen egg white lysozyme in mice deficient in the CD40-CD40 ligand or B7-CD28 costimulatory pathways. The frequency of T cells was decreased by between 3- and 4-fold in CD40-/- mice, and 12-fold in B7-1/B7-2-/- mice, but surprisingly, the relative distribution of T cells responding to peptides that were presented at levels that differed by >250-fold was similar. We also examined the CD4 response after blocking the regulatory molecule CTLA-4 during immunization. We observed no difference in either the frequency or specificity of the CD4+ T cell response if CTLA-4 was blocking during priming. Thus, the T cell response was generated toward the constellation of chemically dominant and subdominant epitopes as a whole, and did not discriminate among them based on their relative abundance.

Hoxb4 overexpression in CD4 memory phenotype T cells increases the central memory population upon homeostatic proliferation.

PubMed

Frison, Héloïse; Giono, Gloria; Thébault, Paméla; Fournier, Marilaine; Labrecque, Nathalie; Bijl, Janet J

2013-01-01

Memory T cell populations allow a rapid immune response to pathogens that have been previously encountered and thus form the basis of success in vaccinations. However, the molecular pathways underlying the development and maintenance of these cells are only starting to be unveiled. Memory T cells have the capacity to self renew as do hematopoietic stem cells, and overlapping gene expression profiles suggested that these cells might use the same self-renewal pathways. The transcription factor Hoxb4 has been shown to promote self-renewal divisions of hematopoietic stem cells resulting in an expansion of these cells. In this study we investigated whether overexpression of Hoxb4 could provide an advantage to CD4 memory phenotype T cells in engrafting the niche of T cell deficient mice following adoptive transfer. Competitive transplantation experiments demonstrated that CD4 memory phenotype T cells derived from mice transgenic for Hoxb4 contributed overall less to the repopulation of the lymphoid organs than wild type CD4 memory phenotype T cells after two months. These proportions were relatively maintained following serial transplantation in secondary and tertiary mice. Interestingly, a significantly higher percentage of the Hoxb4 CD4 memory phenotype T cell population expressed the CD62L and Ly6C surface markers, characteristic for central memory T cells, after homeostatic proliferation. Thus Hoxb4 favours the maintenance and increase of the CD4 central memory phenotype T cell population. These cells are more stem cell like and might eventually lead to an advantage of Hoxb4 T cells after subjecting the cells to additional rounds of proliferation.

T cell responses in senior patients with community-acquired pneumonia related to disease severity.

PubMed

Bian, Lu-Qin; Bi, Ying; Zhou, Shao-Wei; Chen, Zi-Dan; Wen, Jun; Shi, Jin; Mao, Ling; Wang, Ling

2017-12-01

Senior individuals older than 65 years of age are at a disproportionally higher risk of developing pneumonia. Impaired capacity to defend against airway infections may be one of the reasons. It is generally believed that weaker regulatory T cell responses may be beneficial to host defense against pathogens. In senior patients with community-acquired bacterial pneumonia, we investigated the frequencies and functions of regulatory T cells. Interestingly, we found that compared to age- and sex-matched healthy controls, senior pneumonia patients presented lower frequencies of Foxp3-expressing and Helios-expressing CD4 + T cells. The quantity of Foxp3 and Helios being expressed, measured by their mRNA transcription levels, was also lower in CD4 + T cells from pneumonia patients. Furthermore, following TCR and TGF-β stimulation, pneumonia patients presented impaired capacity to upregulate Foxp3 and Helios. Functional analyses revealed that CD4 + T cells from pneumonia patients secreted lower amounts of IL-10 and TGF-β, two cytokines critical to regulatory T cell-mediated suppression. Also, the expression of granzyme B and perforin, which were cytolytic molecules potentially utilized by regulatory T cells to mediate the elimination of antigen-presenting cells and effector T cells, were reduced in CD4 + CD25 + T cells from senior pneumonia patients. In addition, the CD4 + CD25 + T cells from senior pneumonia patients presented reduced capacity to suppress effector CD4 + and CD8 + T cell proliferation. Moreover, the value of pneumonia severity index was inversely correlated with several parameters of regulatory T cell function. Together, our results demonstrated that senior pneumonia patients presented a counterintuitive impairment in regulatory T cell responses that was associated with worse prognosis. Copyright © 2017 Elsevier Inc. All rights reserved.

Peripheral T-cell lymphomas of follicular helper T-cell type frequently display an aberrant CD3(-/dim)CD4(+) population by flow cytometry: an important clue to the diagnosis of a Hodgkin lymphoma mimic.

PubMed

Alikhan, Mir; Song, Joo Y; Sohani, Aliyah R; Moroch, Julien; Plonquet, Anne; Duffield, Amy S; Borowitz, Michael J; Jiang, Liuyan; Bueso-Ramos, Carlos; Inamdar, Kedar; Menon, Madhu P; Gurbuxani, Sandeep; Chan, Ernest; Smith, Sonali M; Nicolae, Alina; Jaffe, Elaine S; Gaulard, Philippe; Venkataraman, Girish

2016-10-01

Nodal follicular helper T-cell-derived lymphoproliferations (specifically the less common peripheral T-cell lymphomas of follicular type) exhibit a spectrum of histologic features that may mimic reactive hyperplasia or Hodgkin lymphoma. Even though angioimmunoblastic T-cell lymphoma and peripheral T-cell lymphoma of follicular type share a common biologic origin from follicular helper T-cells and their morphology has been well characterized, flow cytometry of peripheral T-cell lymphomas of follicular type has not been widely discussed as a tool for identifying this reactive hyperplasia/Hodgkin lymphoma mimic. We identified 10 peripheral T-cell lymphomas of follicular type with available flow cytometry data from five different institutions, including two cases with peripheral blood evaluation. For comparison, we examined flow cytometry data for 8 classical Hodgkin lymphomas (including 1 lymphocyte-rich classical Hodgkin lymphoma), 15 nodular lymphocyte predominant Hodgkin lymphomas, 15 angioimmunoblastic T-cell lymphomas, and 26 reactive nodes. Lymph node histology and flow cytometry data were reviewed, specifically for the presence of a CD3(-/dim)CD4(+) aberrant T-cell population (described in angioimmunoblastic T-cell lymphomas), besides other T-cell aberrancies. Nine of 10 (90%) peripheral T-cell lymphomas of follicular type showed a CD3(-/dim)CD4(+) T-cell population constituting 29.3% (range 7.9-62%) of all lymphocytes. Five of 10 (50%) had nodular lymphocyte predominant Hodgkin lymphoma or lymphocyte-rich classical Hodgkin lymphoma-like morphology with scattered Hodgkin-like cells that expressed CD20, CD30, CD15, and MUM1. Three cases had a nodular growth pattern and three others exhibited a perifollicular growth pattern without Hodgkin-like cells. Epstein-Barr virus was positive in 1 of 10 cases (10%). PCR analysis showed clonal T-cell receptor gamma gene rearrangement in all 10 peripheral T-cell lymphomas of follicular type. By flow cytometry, 11 of 15 (73.3%) angioimmunoblastic T-cell lymphomas showed the CD3(-/dim)CD4(+) population (mean: 19.5%, range: 3-71.8%). Using a threshold of 3% for CD3(-/dim)CD4(+) T cells, all 15 nodular lymphocyte predominant Hodgkin lymphoma controls and 8 classical Hodgkin lymphomas were negative (Mann-Whitney P=0.01, F-PTCL vs Hodgkin lymphomas), as were 25 of 26 reactive lymph nodes. The high frequency of CD3(-/dim)CD4(+) aberrant T cells is similar in angioimmunoblastic T-cell lymphomas and peripheral T-cell lymphomas of follicular type, and is a useful feature in distinguishing peripheral T-cell lymphomas of follicular type from morphologic mimics such as reactive hyperplasia or Hodgkin lymphoma.

Third-party CD4+ invariant natural killer T cells protect from murine GVHD lethality

PubMed Central

Schneidawind, Dominik; Baker, Jeanette; Pierini, Antonio; Buechele, Corina; Luong, Richard H.; Meyer, Everett H.

2015-01-01

Graft-versus-host disease (GVHD) is driven by extensive activation and proliferation of alloreactive donor T cells causing significant morbidity and mortality following allogeneic hematopoietic cell transplantation (HCT). Invariant natural killer T (iNKT) cells are a potent immunoregulatory T-cell subset in both humans and mice. Here, we explored the role of adoptively transferred third-party CD4+ iNKT cells for protection from lethal GVHD in a murine model of allogeneic HCT across major histocompatibility barriers. We found that low numbers of CD4+ iNKT cells from third-party mice resulted in a significant survival benefit with retained graft-versus-tumor effects. In vivo expansion of alloreactive T cells was diminished while displaying a T helper cell 2-biased phenotype. Notably, CD4+ iNKT cells from third-party mice were as protective as CD4+ iNKT cells from donor mice although third-party CD4+ iNKT cells were rejected early after allogeneic HCT. Adoptive transfer of third-party CD4+ iNKT cells resulted in a robust expansion of donor CD4+CD25+FoxP3+ regulatory T cells (Tregs) that were required for protection from lethal GVHD. However, in vivo depletion of myeloid-derived suppressor cells abrogated both Treg expansion and protection from lethal GVHD. Despite the fact that iNKT cells are a rare cell population, the almost unlimited third-party availability and feasibility of in vitro expansion provide the basis for clinical translation. PMID:25795920

Antifibrotic Therapy in Simian Immunodeficiency Virus Infection Preserves CD4+ T-Cell Populations and Improves Immune Reconstitution With Antiretroviral Therapy

PubMed Central

Estes, Jacob D.; Reilly, Cavan; Trubey, Charles M.; Fletcher, Courtney V.; Cory, Theodore J.; Piatak, Michael; Russ, Samuel; Anderson, Jodi; Reimann, Thomas G.; Star, Robert; Smith, Anthony; Tracy, Russell P.; Berglund, Anna; Schmidt, Thomas; Coalter, Vicky; Chertova, Elena; Smedley, Jeremy; Haase, Ashley T.; Lifson, Jeffrey D.; Schacker, Timothy W.

2015-01-01

Even with prolonged antiretroviral therapy (ART), many human immunodeficiency virus-infected individuals have <500 CD4+ T cells/µL, and CD4+ T cells in lymphoid tissues remain severely depleted, due in part to fibrosis of the paracortical T-cell zone (TZ) that impairs homeostatic mechanisms required for T-cell survival. We therefore used antifibrotic therapy in simian immunodeficiency virus-infected rhesus macaques to determine whether decreased TZ fibrosis would improve reconstitution of peripheral and lymphoid CD4+ T cells. Treatment with the antifibrotic drug pirfenidone preserved TZ architecture and was associated with significantly larger populations of CD4+ T cells in peripheral blood and lymphoid tissues. Combining pirfenidone with an ART regimen was associated with greater preservation of CD4+ T cells than ART alone and was also associated with higher pirfenidone concentrations. These data support a potential role for antifibrotic drug treatment as adjunctive therapy with ART to improve immune reconstitution. PMID:25246534

Glycosylphosphatidylinositol-Anchored Anti-HIV scFv Efficiently Protects CD4 T Cells from HIV-1 Infection and Deletion in hu-PBL Mice

PubMed Central

Ye, Chaobaihui; Wang, Weiming; Cheng, Liang; Li, Guangming; Wen, Michael; Wang, Qi; Zhang, Qing; Li, Dan

2016-01-01

ABSTRACT Despite success in viral inhibition and CD4 T cell recovery by highly active antiretroviral treatment (HAART), HIV-1 is still not curable due to the persistence of the HIV-1 reservoir during treatment. One patient with acute myeloid leukemia who received allogeneic hematopoietic stem cell transplantation from a homozygous CCR5 Δ32 donor has had no detectable viremia for 9 years after HAART cessation. This case has inspired a field of HIV-1 cure research focusing on engineering HIV-1 resistance in permissive cells. Here, we employed a glycosylphosphatidylinositol (GPI)-scFv X5 approach to confer resistance of human primary CD4 T cells to HIV-1. We showed that primary CD4 T cells expressing GPI-scFv X5 were resistant to CCR5 (R5)-, CXCR4 (X4)-, and dual-tropic HIV-1 and had a survival advantage compared to control cells ex vivo. In a hu-PBL mouse study, GPI-scFv X5-transduced CD4 T cells were selected in peripheral blood and lymphoid tissues upon HIV-1 infection. Finally, GPI-scFv X5-transduced CD4 T cells, after being cotransfused with HIV-infected cells, showed significantly reduced viral loads and viral RNA copy numbers relative to CD4 cells in hu-PBL mice compared to mice with GPI-scFv AB65-transduced CD4 T cells. We conclude that GPI-scFv X5-modified CD4 T cells could potentially be used as a genetic intervention against both R5- and X4-tropic HIV-1 infections. IMPORTANCE Blocking of HIV-1 entry is one of most promising approaches for therapy. Genetic disruption of the HIV-1 coreceptor CCR5 by nucleases in T cells is under 2 clinical trials and leads to reduced viremia in patients. However, the emergence of viruses using the CXCR4 coreceptor is a concern for therapies applying single-coreceptor disruption. Here, we report that HIV-1-permissive CD4 T cells engineered with GPI-scFv X5 are resistant to R5-, X4-, or dual-tropic virus infection ex vivo. In a preclinical study using hu-PBL mice, we show that CD4 T cells were protected and that GPI-scFv X5-transduced cells were selected in HIV-1-infected animals. Moreover, we show that GPI-scFv X5-transduced CD4 T cells exerted a negative effect on virus replication in vivo. We conclude that GPI-scFv X5-modified CD4 T cells could potentially be used as a genetic intervention against both R5- and X4-tropic HIV-1 infections. PMID:27881659

IL-6-mediated environmental conditioning of defective Th1 differentiation dampens antitumour immune responses in old age.

PubMed

Tsukamoto, Hirotake; Senju, Satoru; Matsumura, Keiko; Swain, Susan L; Nishimura, Yasuharu

2015-04-07

Decline in immune function and inflammation concomitantly develop with ageing. Here we focus on the impact of this inflammatory environment on T cells, and demonstrate that in contrast to successful tumour elimination in young mice, replenishment of tumour-specific CD4(+) T cells fails to induce tumour regression in aged hosts. The impaired antitumour effect of CD4(+) T cells with their defective Th1 differentiation in an aged environment is restored by interleukin (IL)-6 blockade or IL-6 deficiency. IL-6 blockade also restores the impaired ability of CD4(+) T cells to promote CD8(+) T-cell-dependent tumour elimination in aged mice, which requires IFN-γ. Furthermore, IL-6-stimulated production of IL-4/IL-21 through c-Maf induction is responsible for impaired Th1 differentiation. IL-6 also contributes to IL-10 production from CD4(+) T cells in aged mice, causing attenuated responses of CD8(+) T cells. These findings suggest that IL-6 serves as an extrinsic factor counteracting CD4(+) T-cell-mediated immunity against tumour in old age.

Comparative magnitude and kinetics of human cytomegalovirus-specific CD4⁺ and CD8⁺ T-cell responses in pregnant women with primary versus remote infection and in transmitting versus non-transmitting mothers: Its utility for dating primary infection in pregnancy.

PubMed

Fornara, Chiara; Furione, Milena; Arossa, Alessia; Gerna, Giuseppe; Lilleri, Daniele

2016-07-01

To discriminate between primary (PI) and remote (RI) human cytomegalovirus (HCMV) infection, several immunological parameters were monitored for a 2-year period in 53 pregnant women with PI, and 33 pregnant women experiencing HCMV PI at least 5 years prior. Cytokine (IFN-γ and IL-2) production by and phenotype (effector/memory CD45RA(+)) of HCMV-specific CD4(+) and CD8(+) T-cells as well as the lymphoproliferative responses (LPR) were evaluated, with special reference to the comparison between a group of women transmitting (T) and a group of non-transmitting (NT) the infection to fetus. While HCMV-specific CD4(+) T-cells reached at 90 days post-infection (p.i.) values comparable to RI, CD8(+) T-cells reached at 60 days p.i. levels significantly higher and persisting throughout the entire follow-up. Instead, IL-2 production and lymphoproliferative responses were lower in PI than RI for the entire follow-up period. Effector memory CD45RA(+) CD4(+) and CD8(+) HCMV-specific T-cells increased until 90 days p.i., reaching and maintaining levels higher than RI. The comparison between T and NT women showed that, at 30 days p.i., in NT women there was a significantly higher IL-2 production by HCMV-specific CD4(+) T-cells, and at 60 days p.i. a significantly higher frequency of both specific CD4(+) and CD8(+) CD45RA(+) T-cells. HCMV T-cell response appears to correlate with virus transmission to fetus and some parameters (CD4(+) lymphoproliferation, and frequency of HCMV-specific CD8(+) IL2(+) T-cells) may help in dating PI during pregnancy. © 2015 Wiley Periodicals, Inc.

Comparative study of CD4 and CD45RO T cells and CD20 B cells in cerebrospinal fluid of syphilitic meningitis and tuberculous meningitis patients.

PubMed

Yu, Nian; Zhang, Qiao-Quan; Zhang, Kang; Xie, Yuan; Zhu, Hai-Qing; Lin, Xing-Jian; Di, Qing

2016-09-01

This study was to investigate the differences of lymphocyte in the cerebrospinal fluid (CSF) of patients with syphilis meningitis (SM) and tuberculous meningitis (TBM) for new diagnostic insights. Totally, 79 cases of SM and 45 cases of TBM were enrolled. In the CSF, the CD4, CD45RO or CD20 positive lymphocytes were detected by immunohistochemistry. The proportion of CD4 T cells in the CSF lymphocytes in patients with SM was significantly higher than that in patients with TBM (p < 0.05). After medical therapy, there was a significantly decline trend of the CD4 T-cell proportion in both groups (p < 0.05). The proportion of CD45RO T cells in CSF lymphocytes of patients with SM was less than that of patients with TBM (p < 0.05). After medical therapy, the positive ratio of CD45RO T cells was increased in the CSF of both group patients (p < 0.05). The proportion of CD20B cells in the CSF lymphocytes was not obviously different between the two groups during every stage. In conclusion, there are strong differences of CD4 and CD45RO T-cell ratio, but not the CD20 B cells in the meningitis. CD4 and CD45RO T cells in CSF are a useful complement in differentially diagnosing SM and TBM; it contributes to further understand the pathogenesis and prognosis of SM and TBM. © 2016 APMIS. Published by John Wiley & Sons Ltd.

Dectin-1 diversifies Aspergillus fumigatus–specific T cell responses by inhibiting T helper type 1 CD4 T cell differentiation

PubMed Central

Hohl, Tobias M.; Collins, Nichole; Leiner, Ingrid; Gallegos, Alena; Saijo, Shinobu; Coward, Jesse W.; Iwakura, Yoichiro

2011-01-01

Pulmonary infection of mice with Aspergillus fumigatus induces concurrent T helper type 1 (Th1) and Th17 responses that depend on Toll-like receptor/MyD88 and Dectin-1, respectively. However, the mechanisms balancing Th1 and Th17 CD4 T cell populations during infection remain incompletely defined. In this study, we show that Dectin-1 deficiency disproportionally increases Th1 responses and decreases Th17 differentiation after A. fumigatus infection. Dectin-1 signaling in A. fumigatus–infected wild-type mice reduces IFN-γ and IL-12p40 expression in the lung, thereby decreasing T-bet expression in responding CD4 T cells and enhancing Th17 responses. Absence of IFN-γ or IL-12p35 in infected mice or T-bet in responding CD4 T cells enhances Th17 differentiation, independent of Dectin-1 expression, in A. fumigatus–infected mice. Transient deletion of monocyte-derived dendritic cells also reduces Th1 and boosts Th17 differentiation of A. fumigatus–specific CD4 T cells. Our findings indicate that Dectin-1–mediated signals alter CD4 T cell responses to fungal infection by decreasing the production of IL-12 and IFN-γ in innate cells, thereby decreasing T-bet expression in A. fumigatus–specific CD4 T cells and enabling Th17 differentiation. PMID:21242294

Strategies to target non-T-cell HIV reservoirs.

PubMed

Sacha, Jonah B; Ndhlovu, Lishomwa C

2016-07-01

A central question for the HIV cure field is to determine new ways to target clinically relevant, latently and actively replicating HIV-infected cells beyond resting memory CD4 T cells, particularly in anatomical areas of low drug penetrability. HIV eradication strategies being positioned for targeting HIV for extinction in the CD4 T-cell compartment may also show promise in non-CD4 T-cells reservoirs. Furthermore, several exciting novel therapeutic approaches specifically focused on HIV clearance from non-CD4 T-cell populations are being developed. Although reservoir validity in these non-CD4 T cells continues to remain debated, this review will highlight recent advances and make an argument as to their clinical relevancy as we progress towards an HIV cure.

Local and Systemic CD4+ T Cell Exhaustion Reverses with Clinical Resolution of Pulmonary Sarcoidosis

PubMed Central

Hawkins, Charlene; Shaginurova, Guzel; Shelton, D. Auriel; Herazo-Maya, Jose D.; Oswald-Richter, Kyra A.; Young, Anjuli; Celada, Lindsay J.; Kaminski, Naftali; Sevin, Carla

2017-01-01

Investigation of the Th1 immune response in sarcoidosis CD4+ T cells has revealed reduced proliferative capacity and cytokine expression upon TCR stimulation. In other disease models, such cellular dysfunction has been associated with a step-wise, progressive loss of T cell function that results from chronic antigenic stimulation. T cell exhaustion is defined by decreased cytokine production upon TCR activation, decreased proliferation, increased expression of inhibitory cell surface receptors, and increased susceptibility to apoptosis. We characterized sarcoidosis CD4+ T cell immune function in systemic and local environments among subjects undergoing disease progression compared to those experiencing disease resolution. Spontaneous and TCR-stimulated Th1 cytokine expression and proliferation assays were performed in 53 sarcoidosis subjects and 30 healthy controls. PD-1 expression and apoptosis were assessed by flow cytometry. Compared to healthy controls, sarcoidosis CD4+ T cells demonstrated reductions in Th1 cytokine expression, proliferative capacity (p < 0.05), enhanced apoptosis (p < 0.01), and increased PD-1 expression (p < 0.001). BAL-derived CD4+ T cells also demonstrated multiple facets of T cell exhaustion (p < 0.05). Reversal of CD4+ T cell exhaustion was observed in subjects undergoing spontaneous resolution (p < 0.05). Sarcoidosis CD4+ T cells exhibit loss of cellular function during progressive disease that follows the archetype of T cell exhaustion. PMID:29234685

HIV-Infected Individuals with Low CD4/CD8 Ratio despite Effective Antiretroviral Therapy Exhibit Altered T Cell Subsets, Heightened CD8+ T Cell Activation, and Increased Risk of Non-AIDS Morbidity and Mortality

PubMed Central

Serrano-Villar, Sergio; Sainz, Talia; Lee, Sulggi A.; Hunt, Peter W.; Sinclair, Elizabeth; Shacklett, Barbara L.; Ferre, April L.; Hayes, Timothy L.; Somsouk, Ma; Hsue, Priscilla Y.; Van Natta, Mark L.; Meinert, Curtis L.; Lederman, Michael M.; Hatano, Hiroyu; Jain, Vivek; Huang, Yong; Hecht, Frederick M.; Martin, Jeffrey N.; McCune, Joseph M.; Moreno, Santiago; Deeks, Steven G.

2014-01-01

A low CD4/CD8 ratio in elderly HIV-uninfected adults is associated with increased morbidity and mortality. A subset of HIV-infected adults receiving effective antiretroviral therapy (ART) fails to normalize this ratio, even after they achieve normal CD4+ T cell counts. The immunologic and clinical characteristics of this clinical phenotype remain undefined. Using data from four distinct clinical cohorts and three clinical trials, we show that a low CD4/CD8 ratio in HIV-infected adults during otherwise effective ART (after CD4 count recovery above 500 cells/mm3) is associated with a number of immunological abnormalities, including a skewed T cell phenotype from naïve toward terminally differentiated CD8+ T cells, higher levels of CD8+ T cell activation (HLADR+CD38+) and senescence (CD28− and CD57+CD28−), and higher kynurenine/tryptophan ratio. Changes in the peripheral CD4/CD8 ratio are also reflective of changes in gut mucosa, but not in lymph nodes. In a longitudinal study, individuals who initiated ART within six months of infection had greater CD4/CD8 ratio increase compared to later initiators (>2 years). After controlling for age, gender, ART duration, nadir and CD4 count, the CD4/CD8 ratio predicted increased risk of morbidity and mortality. Hence, a persistently low CD4/CD8 ratio during otherwise effective ART is associated with increased innate and adaptive immune activation, an immunosenescent phenotype, and higher risk of morbidity/mortality. This ratio may prove useful in monitoring response to ART and could identify a unique subset of individuals needed of novel therapeutic interventions. PMID:24831517

A colitogenic memory CD4+ T cell population mediates gastrointestinal graft-versus-host disease

PubMed Central

Zhou, Vivian; Agle, Kimberle; Chen, Xiao; Beres, Amy; Komorowski, Richard; Belle, Ludovic; Taylor, Carolyn; Zhu, Fenlu; Haribhai, Dipica; Williams, Calvin B.; Verbsky, James; Blumenschein, Wendy; Sadekova, Svetlana; Bowman, Eddie; Ballantyne, Christie; Weaver, Casey; Serody, David A.; Vincent, Benjamin; Serody, Jonathan; Cua, Daniel J.; Drobyski, William R.

2016-01-01

Damage to the gastrointestinal tract is a major cause of morbidity and mortality in graft-versus-host disease (GVHD) and is attributable to T cell–mediated inflammation. In this work, we identified a unique CD4+ T cell population that constitutively expresses the β2 integrin CD11c and displays a biased central memory phenotype and memory T cell transcriptional profile, innate-like properties, and increased expression of the gut-homing molecules α4β7 and CCR9. Using several complementary murine GVHD models, we determined that adoptive transfer and early accumulation of β2 integrin–expressing CD4+ T cells in the gastrointestinal tract initiated Th1-mediated proinflammatory cytokine production, augmented pathological damage in the colon, and increased mortality. The pathogenic effect of this CD4+ T cell population critically depended on coexpression of the IL-23 receptor, which was required for maximal inflammatory effects. Non–Foxp3-expressing CD4+ T cells produced IL-10, which regulated colonic inflammation and attenuated lethality in the absence of functional CD4+Foxp3+ T cells. Thus, the coordinate expression of CD11c and the IL-23 receptor defines an IL-10–regulated, colitogenic memory CD4+ T cell subset that is poised to initiate inflammation when there is loss of tolerance and breakdown of mucosal barriers. PMID:27500496

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

PubMed Central

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

1996-01-01

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

Novel mode of action of the calcium antagonist mibefradil (Ro 40-5967): potent immunosuppression by inhibition of T-cell infiltration through allogeneic endothelium.

PubMed Central

Blaheta, R A; Hailer, N P; Brude, N; Wittig, B; Oppermann, E; Leckel, K; Harder, S; Scholz, M; Weber, S; Encke, A; Markus, B H

1998-01-01

Cyclosporin A reduces the mitotic activity of allosensitized lymphocytes, but fails to limit emigration of these cells into the donor organ. However, the modulation of both lymphocyte proliferation and infiltration are desirable characteristics of immunosuppressive therapy. The calcium-channel blocker, verapamil, has recently been shown to effectively prevent the transmigration of CD4+ and CD8+ T cells through allogeneic endothelium. Mibefradil (Ro 40-5967) represents a new generation of calcium antagonists with high potency and long-term activity. To evaluate the immunosuppressive potential of this drug, the influence of mibefradil on lymphocyte adhesion to, horizontal locomotion along, and penetration through allogeneic endothelium (HUVEC) was performed. When lymphocytes were prestimulated for 24 hr with mibefradil, adhesion and penetration were dose-dependently reduced. The adhesion ID50 values were 3.4 microM (CD4+ T cells) versus 9.2 microM (CD8+ T cells) and 2.1 microM (CD4+ T cells) versus 3.9 microM (CD8+ T cells) with regard to penetration. Mibefradil also effectively blocked horizontal locomotion. Specific down-regulation of T-cell binding to the P-selection receptor (ID50: CD4+ T cells, 0.8 microM: CD8+ T cells, 1.2 microM) and to the intracellular adhesion molecule-1 (ICAM-1) receptor (ID50: CD4+ T cells, 1.9 microM; CD8+ T cells, 1.5 microM) by mibefradil seems to be responsible for the decreased adhesion and penetration rates. Reduction of intracellular F-actin in T lymphocytes could diminish cell locomotion. In conclusion, the potent suppressive properties of mibefradil support its use as a co-medication in cyclosporin A-based immunosuppressive therapy. PMID:9741343

Novel mode of action of the calcium antagonist mibefradil (Ro 40-5967): potent immunosuppression by inhibition of T-cell infiltration through allogeneic endothelium.

PubMed

Blaheta, R A; Hailer, N P; Brude, N; Wittig, B; Oppermann, E; Leckel, K; Harder, S; Scholz, M; Weber, S; Encke, A; Markus, B H

1998-06-01

Cyclosporin A reduces the mitotic activity of allosensitized lymphocytes, but fails to limit emigration of these cells into the donor organ. However, the modulation of both lymphocyte proliferation and infiltration are desirable characteristics of immunosuppressive therapy. The calcium-channel blocker, verapamil, has recently been shown to effectively prevent the transmigration of CD4+ and CD8+ T cells through allogeneic endothelium. Mibefradil (Ro 40-5967) represents a new generation of calcium antagonists with high potency and long-term activity. To evaluate the immunosuppressive potential of this drug, the influence of mibefradil on lymphocyte adhesion to, horizontal locomotion along, and penetration through allogeneic endothelium (HUVEC) was performed. When lymphocytes were prestimulated for 24 hr with mibefradil, adhesion and penetration were dose-dependently reduced. The adhesion ID50 values were 3.4 microM (CD4+ T cells) versus 9.2 microM (CD8+ T cells) and 2.1 microM (CD4+ T cells) versus 3.9 microM (CD8+ T cells) with regard to penetration. Mibefradil also effectively blocked horizontal locomotion. Specific down-regulation of T-cell binding to the P-selection receptor (ID50: CD4+ T cells, 0.8 microM: CD8+ T cells, 1.2 microM) and to the intracellular adhesion molecule-1 (ICAM-1) receptor (ID50: CD4+ T cells, 1.9 microM; CD8+ T cells, 1.5 microM) by mibefradil seems to be responsible for the decreased adhesion and penetration rates. Reduction of intracellular F-actin in T lymphocytes could diminish cell locomotion. In conclusion, the potent suppressive properties of mibefradil support its use as a co-medication in cyclosporin A-based immunosuppressive therapy.

HIV infection impairs Th1 and Th17 Mycobacterium tuberculosis-specific T cell responses

PubMed Central

Murray, Lyle W; Satti, Iman; Meyerowitz, Jodi; Jones, Matthew; Willberg, Christian B; Ussher, James E; Goedhals, Dominique; Hurst, Jacob; Phillips, Rodney E; McShane, Helen

2018-01-01

Background HIV-infected individuals have a higher risk of developing active tuberculosis than HIV-uninfected individuals, but the mechanisms underpinning this are unclear. We hypothesized that depletion of specific components of Mycobacterium tuberculosis (M.tb)-specific CD4+ and CD8+ T cell responses contributed to this increased risk. Methods M.tb-specific T cell responses in 147 HIV-infected and 44 HIV-uninfected control subjects in a TB-endemic setting in Bloemfontein, South Africa were evaluated. Using a whole-blood flow cytometry assay, we measured expression of IFNγ, TNFα, IL-2 and IL-17 in CD4+ and CD8+ T cells in response to M.tb antigens (PPD, ESAT-6/CFP-10 (EC) and DosR regulon-encoded α-crystallin (Rv2031c)). Results Fewer HIV-infected individuals had detectable CD4+ and CD8+ T cell responses to PPD and Rv2031c than HIV-uninfected subjects. M.tb-specific T cells showed distinct patterns of cytokine expression comprising both Th1 (CD4 and CD8) and Th17 (CD4) cytokines, the latter at highest frequency for Rv2031c. Th17 antigen-specific responses to all antigens tested were specifically impaired in HIV-infected individuals. Conclusions HIV-associated impairment of CD4+ and CD8+ M.tb-specific T cell responses is antigen-specific, particularly impacting responses to PPD and Rv2031c. Preferential depletion of Th17 cytokine-expressing CD4+ T cells suggests this T cell subset may be key to TB susceptibility in HIV-infected individuals. PMID:29546381

CD40L+ CD4+ memory T cells migrate in a CD62P-dependent fashion into reactive lymph nodes and license dendritic cells for T cell priming

PubMed Central

Martín-Fontecha, Alfonso; Baumjohann, Dirk; Guarda, Greta; Reboldi, Andrea; Hons, Miroslav; Lanzavecchia, Antonio; Sallusto, Federica

2008-01-01

There is growing evidence that the maturation state of dendritic cells (DCs) is a critical parameter determining the balance between tolerance and immunity. We report that mouse CD4+ effector memory T (TEM) cells, but not naive or central memory T cells, constitutively expressed CD40L at levels sufficient to induce DC maturation in vitro and in vivo in the absence of antigenic stimulation. CD4+ TEM cells were excluded from resting lymph nodes but migrated in a CD62P-dependent fashion into reactive lymph nodes that were induced to express CD62P, in a transient or sustained fashion, on high endothelial venules. Trafficking of CD4+ TEM cells into chronic reactive lymph nodes maintained resident DCs in a mature state and promoted naive T cell responses and experimental autoimmune encephalomyelitis (EAE) to antigens administered in the absence of adjuvants. Antibodies to CD62P, which blocked CD4+ TEM cell migration into reactive lymph nodes, inhibited DC maturation, T cell priming, and induction of EAE. These results show that TEM cells can behave as endogenous adjuvants and suggest a mechanistic link between lymphocyte traffic in lymph nodes and induction of autoimmunity. PMID:18838544

Ablation of SLP-76 signaling after T cell priming generates memory CD4 T cells impaired in steady-state and cytokine-driven homeostasis.

PubMed

Bushar, Nicholas D; Corbo, Evann; Schmidt, Michelle; Maltzman, Jonathan S; Farber, Donna L

2010-01-12

The intracellular signaling mechanisms regulating the generation and long-term persistence of memory T cells in vivo remain unclear. In this study, we used mouse models with conditional deletion of the key T cell receptor (TCR)-coupled adaptor molecule SH2-domain-containing phosphoprotein of 76 kDa (SLP-76), to analyze signaling mechanisms for memory CD4 T cell generation, maintenance, and homeostasis. We found that ablation of SLP-76 expression after T cell priming did not inhibit generation of phenotypic effector or memory CD4 T cells; however, the resultant SLP-76-deficient memory CD4 T cells could not produce recall cytokines in response to TCR-mediated stimulation and showed decreased persistence in vivo. In addition, SLP-76-deficient memory CD4 T cells exhibited reduced steady-state homeostasis and were impaired in their ability to homeostatically expand in vivo in response to the gamma(c) cytokine IL-7, despite intact proximal signaling through the IL-7R-coupled JAK3/STAT5 pathway. Direct in vivo deletion of SLP-76 in polyclonal memory CD4 T cells likewise led to impaired steady-state homeostasis as well as impaired homeostatic responses to IL-7. Our findings demonstrate a dominant role for SLP-76-dependent TCR signals in regulating turnover and perpetuation of memory CD4 T cells and their responses to homeostatic cytokines, with implications for the selective survival of memory CD4 T cells following pathogen exposure, vaccination, and aging.

Antigen-specific and non-specific CD4{sup +} T cell recruitment and proliferation during influenza infection

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

Chapman, Timothy J.; Castrucci, Maria R.; Padrick, Ryan C.

To track epitope-specific CD4{sup +} T cells at a single-cell level during influenza infection, the MHC class II-restricted OVA{sub 323-339} epitope was engineered into the neuraminidase stalk of influenza/A/WSN, creating a surrogate viral antigen. The recombinant virus, influenza A/WSN/OVA{sub II}, replicated well, was cleared normally, and stimulated both wild-type and DO11.10 or OT-II TCR transgenic OVA-specific CD4{sup +} T cells. OVA-specific CD4 T cells proliferated during infection only when the OVA epitope was present. However, previously primed (but not naive) transgenic CD4{sup +} T cells were recruited to the infected lung both in the presence and absence of the OVA{submore » 323-339} epitope. These data show that, when primed, CD4{sup +} T cells may traffic to the lung in the absence of antigen, but do not proliferate. These results also document a useful tool for the study of CD4 T cells in influenza infection.« less

Granulysin-Expressing CD4+ T Cells as Candidate Immune Marker for Tuberculosis during Childhood and Adolescence

PubMed Central

Mueller, Henrik; Faé, Kellen C.; Magdorf, Klaus; Ganoza, Christian A.; Wahn, Ulrich; Guhlich, Ute; Feiterna-Sperling, Cornelia; Kaufmann, Stefan H. E.

2011-01-01

Background Granulysin produced by cytolytic T cells directly contributes to immune defense against tuberculosis (TB). We investigated granulysin as a candidate immune marker for childhood and adolescent TB. Methods Peripheral blood mononuclear cells (PBMC) from children and adolescents (1–17 years) with active TB, latent TB infection (LTBI), nontuberculous mycobacteria (NTM) infection and from uninfected controls were isolated and restimulated in a 7-day restimulation assay. Intracellular staining was then performed to analyze antigen-specific induction of activation markers and cytotoxic proteins, notably, granulysin in CD4+ CD45RO+ memory T cells. Results CD4+ CD45RO+ T cells co-expressing granulysin with specificity for Mycobacterium tuberculosis (Mtb) were present in high frequency in TB-experienced children and adolescents. Proliferating memory T cells (CFSElowCD4+CD45RO+) were identified as main source of granulysin and these cells expressed both central and effector memory phenotype. PBMC from study participants after TB drug therapy revealed that granulysin-expressing CD4+ T cells are long-lived, and express several activation and cytotoxicity markers with a proportion of cells being interferon-gamma-positive. In addition, granulysin-expressing T cell lines showed cytolytic activity against Mtb-infected target cells. Conclusions Our data suggest granulysin expression by CD4+ memory T cells as candidate immune marker for TB infection, notably, in childhood and adolescence. PMID:22216262

Identifying the Target Cell in Primary Simian Immunodeficiency Virus (SIV) Infection: Highly Activated Memory CD4+ T Cells Are Rapidly Eliminated in Early SIV Infection In Vivo

PubMed Central

Veazey, Ronald S.; Tham, Irene C.; Mansfield, Keith G.; DeMaria, MaryAnn; Forand, Amy E.; Shvetz, Daniel E.; Chalifoux, Laura V.; Sehgal, Prabhat K.; Lackner, Andrew A.

2000-01-01

It has recently been shown that rapid and profound CD4+ T-cell depletion occurs almost exclusively within the intestinal tract of simian immunodeficiency virus (SIV)-infected macaques within days of infection. Here we demonstrate (by three- and four-color flow cytometry) that this depletion is specific to a definable subset of CD4+ T cells, namely, those having both a highly and/or acutely activated (CD69+ CD38+ HLA-DR+) and memory (CD45RA− Leu8−) phenotype. Moreover, we demonstrate that this subset of helper T cells is found primarily within the intestinal lamina propria. Viral tropism for this particular cell type (which has been previously suggested by various studies in vitro) could explain why profound CD4+ T-cell depletion occurs in the intestine and not in peripheral lymphoid tissues in early SIV infection. Furthermore, we demonstrate that an acute loss of this specific subset of activated memory CD4+ T cells may also be detected in peripheral blood and lymph nodes in early SIV infection. However, since this particular cell type is present in such small numbers in circulation, its loss does not significantly affect total CD4+ T cell counts. This finding suggests that SIV and, presumably, human immunodeficiency virus specifically infect, replicate in, and eliminate definable subsets of CD4+ T cells in vivo. PMID:10590091

Intraepithelial Attack Rather than Intratumorally Infiltration of CD8+T Lymphocytes is a Favorable Prognostic Indicator in Pancreatic Ductal Adenocarcinoma.

PubMed

Zhang, J; Wang, Y F; Wu, B; Zhong, Z X; Wang, K X; Yang, L Q; Wang, Y Q; Li, Y Q; Gao, J; Li, Z S

2017-01-01

Tumor-infiltrating lymphocytes (TILs) are one of the major participants in the tumor microenvironment of pancreatic ductal adenocarcinoma (PDAC). However, the mechanism of interaction between TILs and tumors is complex and remains unclear. To evaluate the state of immunoreactions in PDAC tissues, and explore the prognostic value of these markers in a large sample, to provide a new theoretical basis for PDAC immunotherapy. Immunohistochemical staining of CD4+ and CD8+T cells was performed in a tissue microarray (TMA) of 143 cases of PDAC. Two major variables for the spatial distributions of CD4+T and CD8+T cells in PDAC tissues, intraepithelial attack and intratumoral infiltration, were used to evaluate the state of immunoreactions, and the interrelationships with the clinicopathological variables were analyzed. Our data showed that both the intraepithelial CD4+T and CD8+T attack were less frequent than the intratumoral infiltration. CD8+T intraepithelial attack and intratumoral infiltration were more intense than CD4+T. CD8+T intraepithelial attack was an independent favorable prognostic factor for overall survival, correlating negatively with vascular invasion and positively with CD4+T and CD8+T high intratumoral infiltration. CD8+T high intratumoral infiltration without CD8+T intraepithelial attack was a poor prognostic factor. CD8+T high intratumoral infiltration was accompanied by T stage progression. Conclusively, in PDAC progression, imbalances of T cells occurred in CD4+ and CD8+ immunoreactions. The CD8+T intraepithelial attack was an independent favorable prognostic indicator, however the intraepithelial attack of CD4+T and the both intratumoral infiltration of CD8+T and CD4+T played an ambiguous role. Our data suggested that it is a potential approach to increasing the number of intraepithelial attacking CD8+T cells for tumor immunotherapy, and exploring a new mechanism for immunosuppression in a tumor microenvironment with high T cell infiltration without attack. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

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.

Colorectal cancer cells suppress CD4+ T cells immunity through canonical Wnt signaling.

PubMed

Sun, Xuan; Liu, Suoning; Wang, Daguang; Zhang, Yang; Li, Wei; Guo, Yuchen; Zhang, Hua; Suo, Jian

2017-02-28

Understanding how colorectal cancer escapes from immunosurveillance and immune attack is important for developing novel immunotherapies for colorectal cancer. In this study we evaluated the role of canonical Wnt signaling in the regulation of T cell function in a mouse colorectal cancer model. We found that colorectal cancer cells expressed abundant Wnt ligands, and intratumoral T cells expressed various Frizzled proteins. Meanwhile, both active β-catenin and total β-catenin were elevated in intratumoral T cells. In vitro study indicated that colorectal cancer cells suppressed IFN-γ expression and increased IL-17a expression in activated CD4+ T cells. However, the cytotoxic activity of CD8+ T cells was not altered by colorectal cancer cells. To further evaluate the importance of Wnt signaling for CD4+ T cell-mediated cancer immunity, β-catenin expression was enforced in CD4+ T cells using lentiviral transduction. In an adoptive transfer model, enforced expression of β-catenin in intratumoral CD4+ T cells increased IL-17a expression, enhanced proliferation and inhibited apoptosis of colorectal cancer cells. Taken together, our study disclosed a new mechanism by which colorectal cancer impairs T cell immunity.

Characterisation of cell functions and receptors in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME).

PubMed

Hardcastle, Sharni Lee; Brenu, Ekua Weba; Johnston, Samantha; Nguyen, Thao; Huth, Teilah; Wong, Naomi; Ramos, Sandra; Staines, Donald; Marshall-Gradisnik, Sonya

2015-06-02

Abnormal immune function is often an underlying component of illness pathophysiology and symptom presentation. Functional and phenotypic immune-related alterations may play a role in the obscure pathomechanism of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME). The objective of this study was to investigate the functional ability of innate and adaptive immune cells in moderate and severe CFS/ME patients. The 1994 Fukuda criteria for CFS/ME were used to define CFS/ME patients. CFS/ME participants were grouped based on illness severity with 15 moderately affected (moderate) and 12 severely affected (severe) CFS/ME patients who were age and sex matched with 18 healthy controls. Flow cytometric protocols were used for immunological analysis of dendritic cells, monocytes and neutrophil function as well as measures of lytic proteins and T, natural killer (NK) and B cell receptors. CFS/ME patients exhibited alterations in NK receptors and adhesion markers and receptors on CD4(+)T and CD8(+)T cells. Moderate CFS/ME patients had increased CD8(+) CD45RA effector memory T cells, SLAM expression on NK cells, KIR2DL5(+) on CD4(+)T cells and BTLA4(+) on CD4(+)T central memory cells. Moderate CFS/ME patients also had reduced CD8(+)T central memory LFA-1, total CD8(+)T KLRG1, naïve CD4(+)T KLRG1 and CD56(dim)CD16(-) NK cell CD2(+) and CD18(+)CD2(+). Severe CFS/ME patients had increased CD18(+)CD11c(-) in the CD56(dim)CD16(-) NK cell phenotype and reduced NKp46 in CD56(bright)CD16(dim) NK cells. This research accentuated the presence of immunological abnormalities in CFS/ME and highlighted the importance of assessing functional parameters of both innate and adaptive immune systems in the illness.

Chronic exposure to trichloroethylene increases DNA methylation of the Ifng promoter in CD4+ T cells.

PubMed

Gilbert, Kathleen M; Blossom, Sarah J; Erickson, Stephen W; Broadfoot, Brannon; West, Kirk; Bai, Shasha; Li, Jingyun; Cooney, Craig A

2016-10-17

CD4 + T cells in female MRL+/+ mice exposed to solvent and water pollutant trichloroethylene (TCE) skew toward effector/memory CD4 + T cells, and demonstrate seemingly non-monotonic alterations in IFN-γ production. In the current study we examined the mechanism for this immunotoxicity using effector/memory and naïve CD4 + T cells isolated every 6 weeks during a 40 week exposure to TCE (0.5mg/ml in drinking water). A time-dependent effect of TCE exposure on both Ifng gene expression and IFN-γ protein production was observed in effector/memory CD4 + T cells, with an increase after 22 weeks of exposure and a decrease after 40 weeks of exposure. No such effect of TCE was observed in naïve CD4 + T cells. A cumulative increase in DNA methylation in the CpG sites of the promoter of the Ifng gene was observed in effector/memory, but not naïve, CD4 + T cells over time. Also unique to the Ifng promoter was an increase in methylation variance in effector/memory compared to naïve CD4 + T cells. Taken together, the CpG sites of the Ifng promoter in effector/memory CD4 + T cells were especially sensitive to the effects of TCE exposure, which may help explain the regulatory effect of the chemical on this gene. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Requirement for CD4 T Cell Help in Generating Functional CD8 T Cell Memory

NASA Astrophysics Data System (ADS)

Shedlock, Devon J.; Shen, Hao

2003-04-01

Although primary CD8 responses to acute infections are independent of CD4 help, it is unknown whether a similar situation applies to secondary responses. We show that depletion of CD4 cells during the recall response has minimal effect, whereas depletion during the priming phase leads to reduced responses by memory CD8 cells to reinfection. Memory CD8 cells generated in CD4+/+ mice responded normally when transferred into CD4-/- hosts, whereas memory CD8 cells generated in CD4-/- mice mounted defective recall responses in CD4+/+ adoptive hosts. These results demonstrate a previously undescribed role for CD4 help in the development of functional CD8 memory.

CD4+CD25+ regulatory T cells suppress allograft rejection mediated by memory CD8+ T cells via a CD30-dependent mechanism.

PubMed

Dai, Zhenhua; Li, Qi; Wang, Yinong; Gao, Ge; Diggs, Lonnette S; Tellides, George; Lakkis, Fadi G

2004-01-01

CD4(+)CD25(+) regulatory T (Treg) cells suppress naive T cell responses, prevent autoimmunity, and delay allograft rejection. It is not known, however, whether Treg cells suppress allograft rejection mediated by memory T cells, as the latter mount faster and stronger immune responses than their naive counterparts. Here we show that antigen-induced, but not naive, Treg cells suppress allograft rejection mediated by memory CD8(+) T cells. Suppression was allospecific, as Treg cells induced by third-party antigens did not delay allograft rejection. In vivo and in vitro analyses revealed that the apoptosis of allospecific memory CD8(+) T cells is significantly increased in the presence of antigen-induced Treg cells, while their proliferation remains unaffected. Importantly, neither suppression of allograft rejection nor enhanced apoptosis of memory CD8(+) T cells was observed when Treg cells lacked CD30 or when CD30 ligand-CD30 interaction was blocked with anti-CD30 ligand Ab. This study therefore provides direct evidence that pathogenic memory T cells are amenable to suppression in an antigen-specific manner and identifies CD30 as a molecule that is critical for the regulation of memory T cell responses.

CD4+CD25+ regulatory T cells suppress allograft rejection mediated by memory CD8+ T cells via a CD30-dependent mechanism

PubMed Central

Dai, Zhenhua; Li, Qi; Wang, Yinong; Gao, Ge; Diggs, Lonnette S.; Tellides, George; Lakkis, Fadi G.

2004-01-01

CD4+CD25+ regulatory T (Treg) cells suppress naive T cell responses, prevent autoimmunity, and delay allograft rejection. It is not known, however, whether Treg cells suppress allograft rejection mediated by memory T cells, as the latter mount faster and stronger immune responses than their naive counterparts. Here we show that antigen-induced, but not naive, Treg cells suppress allograft rejection mediated by memory CD8+ T cells. Suppression was allospecific, as Treg cells induced by third-party antigens did not delay allograft rejection. In vivo and in vitro analyses revealed that the apoptosis of allospecific memory CD8+ T cells is significantly increased in the presence of antigen-induced Treg cells, while their proliferation remains unaffected. Importantly, neither suppression of allograft rejection nor enhanced apoptosis of memory CD8+ T cells was observed when Treg cells lacked CD30 or when CD30 ligand–CD30 interaction was blocked with anti–CD30 ligand Ab. This study therefore provides direct evidence that pathogenic memory T cells are amenable to suppression in an antigen-specific manner and identifies CD30 as a molecule that is critical for the regulation of memory T cell responses. PMID:14722622

What happens in the thymus does not stay in the thymus: how T cells recycle the CD4+-CD8+ lineage commitment transcriptional circuitry to control their function

PubMed Central

Vacchio, Melanie S.; Bosselut, Rémy

2016-01-01

MHC-restricted CD4+ and CD8+ T cell are at the core of most adaptive immune responses. Although these cells carry distinct functions, they arise from a common precursor during thymic differentiation, in a developmental sequence that matches CD4 and CD8 expression and functional potential with MHC restriction. While the transcriptional control of CD4+-CD8+ lineage choice in the thymus is now better understood, less was known about what maintains the CD4+- and CD8+-lineage integrity of mature T cells. In this review, we discuss the mechanisms that establish in the thymus, and maintain in post-thymic cells, the separation of these lineages. We focus on recent studies that address the mechanisms of epigenetic control of Cd4 expression and emphasize how maintaining a transcriptional circuitry nucleated around Thpok and Runx proteins, the key architects of CD4+-CD8+ lineage commitment in the thymus, is critical for CD4+ T cell helper functions. PMID:27260768

A pathway of costimulation that prevents anergy in CD28- T cells: B7- independent costimulation of CD1-restricted T cells

PubMed Central

1995-01-01

A class of molecules that is expressed on antigen presenting cells, exemplified by CD80 (B7), has been found to provide a necessary costimulatory signal for T cell activation and proliferation. CD28 and CTLA4 are the B7 counterreceptors and are expressed on the majority of human CD4+ T cells and many CD8+ T cells. The signal these molecules mediate is distinguished from other costimulatory signals by the finding that T cell recognition of antigen results in a prolonged state of T cell unresponsiveness or anergy, unless these costimulatory molecules are engaged. However, nearly half of the CD8+ and CD4-CD8- T cells lack CD28, and the costimulatory signals required for the activation of such cells are unknown. To understand the pathways of activation used by CD28- T cells, we have examined the costimulatory requirements of antigen-specific CD4-CD8- TCR(+)-alpha/beta circulating T cells that lack the expression of CD28. We have characterized two T cell lines, DN1 and DN6, that recognize a mycobacterial antigen, and are restricted not by major histocompatibility complex class I or II, but by CD1b or CD1c, two members of a family of major histocompatibility complex-related molecules that have been recently implicated in a distinct pathway for antigen presentation. Comparison of antigen-specific cytolytic responses of the DN1 and DN6 T cell lines against antigen-pulsed CD1+ monocytes or CD1+ B lymphoblastoid cell lines (B-LCL) demonstrated that these T cells recognized antigen presented by both types of cells. However, T cell proliferation occurred only when antigen was presented by CD1+ monocytes, indicating that the CD1+ monocytes expressed a costimulatory molecule that the B- LCL transfectants lacked. This hypothesis was confirmed by demonstrating that the T cells became anergic when incubated with the CD1(+)-transfected B-LCL in the presence of antigen, but not in the absence of antigen. The required costimulatory signal occurred by a CD28-independent mechanism since both the CD1+ monocytes and CD1+ B-LCL transfectants expressed B7-1 and B7-2, and DN1 and DN6 lacked surface expression of CD28. We propose that these data define a previously unrecognized pathway of costimulation for T cells distinct from that involving CD28 and its counterreceptors. We suggest that this B7- independent pathway plays a crucial role in the activation and maintenance of tolerance of at least a subset of CD28- T cells. PMID:7500046

High-throughput epitope discovery reveals frequent recognition of neo-antigens by CD4+ T cells in human melanoma.

PubMed

Linnemann, Carsten; van Buuren, Marit M; Bies, Laura; Verdegaal, Els M E; Schotte, Remko; Calis, Jorg J A; Behjati, Sam; Velds, Arno; Hilkmann, Henk; Atmioui, Dris El; Visser, Marten; Stratton, Michael R; Haanen, John B A G; Spits, Hergen; van der Burg, Sjoerd H; Schumacher, Ton N M

2015-01-01

Tumor-specific neo-antigens that arise as a consequence of mutations are thought to be important for the therapeutic efficacy of cancer immunotherapies. Accumulating evidence suggests that neo-antigens may be commonly recognized by intratumoral CD8+ T cells, but it is unclear whether neo-antigen-specific CD4+ T cells also frequently reside within human tumors. In view of the accepted role of tumor-specific CD4+ T-cell responses in tumor control, we addressed whether neo-antigen-specific CD4+ T-cell reactivity is a common property in human melanoma.

A Novel Epitope from CD22 Regulates Th1 and Th17 Cell Function in Systemic Lupus Erythematosus

PubMed Central

Chen, Xiao; Zhang, Li-Hua; Song, You; Cheng, Xiang; Zhou, Zi-Hua; Wang, Min; Guo, He-Ping; Du, Rong; Liao, Yu-Hua

2013-01-01

The published antibodies (Abs) against CD22 on B cells including Epratuzumab could inhibit B cell activation mainly through binding to C2-set Ig domain of CD22, but they are rarely reported to modulate the pathogenic CD4+ T cell function in systemic lupus erythematosus (SLE). Recently, it was proved that the extracellular amino-terminal V-set Ig domain of CD22 might mediate the interaction of B and T cells, but for now the exact effect of this domain on CD4+ T cell biology have not been identified. Thus, in this study, we screened out a peptide termed B2285 from this V-set Ig domain, developed the novel specific anti-B2285 Abs in rabbits, and investigated their effects in MRL/lpr mice with spontaneous SLE. The results showed that anti-B2285 Abs could ameliorate the disease severity obviously in spontaneous SLE mice with the decreased differentiations of Th1 and Th17 cells and no changes of Th2 and Treg cells. In co-cultured B cells and CD4+ T cells, this specific anti-CD22 Abs was observed to inhibit the anti-dsDNA Abs production, CD4+ T cells proliferation, the protein levels of T-bet and RORγt, and the mRNA levels of TNF-α, IFN-γ, IL-6 and IL-17 in CD4+ T cells. Moreover, the expression of CD45RO on CD4+ T cells could be also apparently diminished by this novel Abs. The data suggested that anti-B2285 Abs could slow SLE progression significantly by regulating Th1 and Th17 cells function via B-T cell interaction and the cytokine network regulation. The treatment against V-set Ig domain of CD22 would be a valuable therapeutic method for SLE and other autoimmune diseases. PMID:23704998

A novel epitope from CD22 regulates Th1 and Th17 cell function in systemic lupus erythematosus.

PubMed

Yuan, Jing; Yu, Miao; Cao, Ai-Lin; Chen, Xiao; Zhang, Li-Hua; Song, You; Cheng, Xiang; Zhou, Zi-Hua; Wang, Min; Guo, He-Ping; Du, Rong; Liao, Yu-Hua

2013-01-01

The published antibodies (Abs) against CD22 on B cells including Epratuzumab could inhibit B cell activation mainly through binding to C2-set Ig domain of CD22, but they are rarely reported to modulate the pathogenic CD4(+) T cell function in systemic lupus erythematosus (SLE). Recently, it was proved that the extracellular amino-terminal V-set Ig domain of CD22 might mediate the interaction of B and T cells, but for now the exact effect of this domain on CD4(+) T cell biology have not been identified. Thus, in this study, we screened out a peptide termed B2285 from this V-set Ig domain, developed the novel specific anti-B2285 Abs in rabbits, and investigated their effects in MRL/lpr mice with spontaneous SLE. The results showed that anti-B2285 Abs could ameliorate the disease severity obviously in spontaneous SLE mice with the decreased differentiations of Th1 and Th17 cells and no changes of Th2 and Treg cells. In co-cultured B cells and CD4(+) T cells, this specific anti-CD22 Abs was observed to inhibit the anti-dsDNA Abs production, CD4(+) T cells proliferation, the protein levels of T-bet and RORγt, and the mRNA levels of TNF-α, IFN-γ, IL-6 and IL-17 in CD4(+) T cells. Moreover, the expression of CD45RO on CD4(+) T cells could be also apparently diminished by this novel Abs. The data suggested that anti-B2285 Abs could slow SLE progression significantly by regulating Th1 and Th17 cells function via B-T cell interaction and the cytokine network regulation. The treatment against V-set Ig domain of CD22 would be a valuable therapeutic method for SLE and other autoimmune diseases.

Equine CD4+ CD25high T cells exhibit regulatory activity by close contact and cytokine-dependent mechanisms in vitro

PubMed Central

Hamza, Eman; Gerber, Vinzenz; Steinbach, Falko; Marti, Eliane

2011-01-01

Horses are particularly prone to allergic and autoimmune diseases, but little information about equine regulatory T cells (Treg) is currently available. The aim of this study therefore was to investigate the existence of CD4+ Treg cells in horses, determine their suppressive function as well as their mechanism of action. Freshly isolated peripheral blood mononuclear cells (PBMC) from healthy horses were examined for CD4, CD25 and forkhead box P3 (FoxP3) expression. We show that equine FoxP3 is expressed constitutively by a population of CD4+ CD25+ T cells, mainly in the CD4+ CD25high subpopulation. Proliferation of CD4+ CD25− sorted cells stimulated with irradiated allogenic PBMC was significantly suppressed in co-culture with CD4+ CD25high sorted cells in a dose-dependent manner. The mechanism of suppression by the CD4+ CD25high cell population is mediated by close contact as well as interleukin (IL)-10 and transforming growth factor-β1 (TGF-β1) and probably other factors. In addition, we studied the in vitro induction of CD4+ Treg and their characteristics compared to those of freshly isolated CD4+ Treg cells. Upon stimulation with a combination of concanavalin A, TGF-β1 and IL-2, CD4+ CD25+ T cells which express FoxP3 and have suppressive capability were induced from CD4+ CD25− cells. The induced CD4+ CD25high express higher levels of IL-10 and TGF-β1 mRNA compared to the freshly isolated ones. Thus, in horses as in man, the circulating CD4+ CD25high subpopulation contains natural Treg cells and functional Treg can be induced in vitro upon appropriate stimulation. Our study provides the first evidence of the regulatory function of CD4+ CD25+ cells in horses and offers insights into ex vivo manipulation of Treg cells. PMID:21977999

Cord blood derived CD4+ CD25(high) T cells become functional regulatory T cells upon antigen encounter.

PubMed

Mayer, Elisabeth; Bannert, Christina; Gruber, Saskia; Klunker, Sven; Spittler, Andreas; Akdis, Cezmi A; Szépfalusi, Zsolt; Eiwegger, Thomas

2012-01-01

Upon antigen exposure, cord blood derived T cells respond to ubiquitous environmental antigens by high proliferation. To date it remains unclear whether these "excessive" responses relate to different regulatory properties of the putative T regulatory cell (Treg) compartment or even expansion of the Treg compartment itself. Cord blood (>37 week of gestation) and peripheral blood (healthy controls) were obtained and different Treg cell subsets were isolated. The suppressive potential of Treg populations after antigen exposure was evaluated via functional inhibition assays ([(3)H]thymidine incorporation assay and CFSE staining) with or without allergen stimulation. The frequency and markers of CD4(+)CD25(high)FoxP3(+) T cells were characterized by mRNA analysis and flow cytometry. Cord blood derived CD4(+)CD25(high) cells did not show substantial suppressor capacity upon TCR activation, in contrast to CD4(+)CD25(high) cells freshly purified from adult blood. This could not be explained by a lower frequency of FoxP3(+)CD4(+)CD25(high)cells or FOXP3 mRNA expression. However, after antigen-specific stimulation in vitro, these cells showed strong proliferation and expansion and gained potent suppressive properties. The efficiency of their suppressive capacity can be enhanced in the presence of endotoxins. If T-cells were sorted according to their CD127 expression, a tiny subset of Treg cells (CD4(+)CD25(+)CD127(low)) is highly suppressive even without prior antigen exposure. Cord blood harbors a very small subset of CD4(+)CD25(high) Treg cells that requires antigen-stimulation to show expansion and become functional suppressive Tregs.

BAFF induces spleen CD4{sup +} T cell proliferation by down-regulating phosphorylation of FOXO3A and activates cyclin D2 and D3 expression

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

Ji, Fang; Chen, Rongjing; Liu, Baojun

2012-09-07

Highlights: Black-Right-Pointing-Pointer Firstly analyze the mechanism of BAFF and anti-CD3 co-stimulation on purified mouse splenic CD4{sup +} T cells. Black-Right-Pointing-Pointer Carrying out siRNA technology to study FOXO3A protein function. Black-Right-Pointing-Pointer Helpful to understand the T cell especially CD4{sup +} T cell's role in immunological reaction. -- Abstract: The TNF ligand family member 'B cell-activating factor belonging to the TNF family' (BAFF, also called BLyS, TALL-1, zTNF-4, and THANK) is an important survival factor for B and T cells. In this study, we show that BAFF is able to induce CD4{sup +} spleen T cell proliferation when co-stimulated with anti-CD3. Expressionmore » of phosphorylated FOXO3A was notably down-regulated and cyclins D2 and D3 were up-regulated and higher in the CD4{sup +} T cells when treated with BAFF and anti-CD3, as assessed by Western blotting. Furthermore, after FOXO3A was knocked down, expression of cyclin D1 was unchanged, compared with control group levels, but the expression of cyclins D2 and D3 increased, compared with the control group. In conclusion, our results suggest that BAFF induced CD4{sup +} spleen T cell proliferation by down-regulating the phosphorylation of FOXO3A and then activating cyclin D2 and D3 expression, leading to CD4{sup +} T cell proliferation.« less

Circulating gluten-specific FOXP3+CD39+ regulatory T cells have impaired suppressive function in patients with celiac disease.

PubMed

Cook, Laura; Munier, C Mee Ling; Seddiki, Nabila; van Bockel, David; Ontiveros, Noé; Hardy, Melinda Y; Gillies, Jana K; Levings, Megan K; Reid, Hugh H; Petersen, Jan; Rossjohn, Jamie; Anderson, Robert P; Zaunders, John J; Tye-Din, Jason A; Kelleher, Anthony D

2017-12-01

Celiac disease is a chronic immune-mediated inflammatory disorder of the gut triggered by dietary gluten. Although the effector T-cell response in patients with celiac disease has been well characterized, the role of regulatory T (Treg) cells in the loss of tolerance to gluten remains poorly understood. We sought to define whether patients with celiac disease have a dysfunction or lack of gluten-specific forkhead box protein 3 (FOXP3) + Treg cells. Treated patients with celiac disease underwent oral wheat challenge to stimulate recirculation of gluten-specific T cells. Peripheral blood was collected before and after challenge. To comprehensively measure the gluten-specific CD4 + T-cell response, we paired traditional IFN-γ ELISpot with an assay to detect antigen-specific CD4 + T cells that does not rely on tetramers, antigen-stimulated cytokine production, or proliferation but rather on antigen-induced coexpression of CD25 and OX40 (CD134). Numbers of circulating gluten-specific Treg cells and effector T cells both increased significantly after oral wheat challenge, peaking at day 6. Surprisingly, we found that approximately 80% of the ex vivo circulating gluten-specific CD4 + T cells were FOXP3 + CD39 + Treg cells, which reside within the pool of memory CD4 + CD25 + CD127 low CD45RO + Treg cells. Although we observed normal suppressive function in peripheral polyclonal Treg cells from patients with celiac disease, after a short in vitro expansion, the gluten-specific FOXP3 + CD39 + Treg cells exhibited significantly reduced suppressive function compared with polyclonal Treg cells. This study provides the first estimation of FOXP3 + CD39 + Treg cell frequency within circulating gluten-specific CD4 + T cells after oral gluten challenge of patients with celiac disease. FOXP3 + CD39 + Treg cells comprised a major proportion of all circulating gluten-specific CD4 + T cells but had impaired suppressive function, indicating that Treg cell dysfunction might be a key contributor to disease pathogenesis. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Generation of TCR-Expressing Innate Lymphoid-like Helper Cells that Induce Cytotoxic T Cell-Mediated Anti-leukemic Cell Response.

PubMed

Ueda, Norihiro; Uemura, Yasushi; Zhang, Rong; Kitayama, Shuichi; Iriguchi, Shoichi; Kawai, Yohei; Yasui, Yutaka; Tatsumi, Minako; Ueda, Tatsuki; Liu, Tian-Yi; Mizoro, Yasutaka; Okada, Chihiro; Watanabe, Akira; Nakanishi, Mahito; Senju, Satoru; Nishimura, Yasuharu; Kuzushima, Kiyotaka; Kiyoi, Hitoshi; Naoe, Tomoki; Kaneko, Shin

2018-06-05

CD4 + T helper (Th) cell activation is essential for inducing cytotoxic T lymphocyte (CTL) responses against malignancy. We reprogrammed a Th clone specific for chronic myelogenous leukemia (CML)-derived b3a2 peptide to pluripotency and re-differentiated the cells into original TCR-expressing T-lineage cells (iPS-T cells) with gene expression patterns resembling those of group 1 innate lymphoid cells. CD4 gene transduction into iPS-T cells enhanced b3a2 peptide-specific responses via b3a2 peptide-specific TCR. iPS-T cells upregulated CD40 ligand (CD40L) expression in response to interleukin-2 and interleukin-15. In the presence of Wilms tumor 1 (WT1) peptide, antigen-specific dendritic cells (DCs) conditioned by CD4-modified CD40L high iPS-T cells stimulated WT1-specific CTL priming, which eliminated WT1 peptide-expressing CML cells in vitro and in vivo. Thus, CD4 modification of CD40L high iPS-T cells generates innate lymphoid helper-like cells inducing bcr-abl-specific TCR signaling that mediates effectiveanti-leukemic CTL responses via DC maturation, showing potential for adjuvant immunotherapy against leukemia. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Circulating CXCR5+CD4+ T cells assist in the survival and growth of primary diffuse large B cell lymphoma cells through interleukin 10 pathway

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

Cha, Zhanshan; Qian, Guangfang; Zang, Yan

Diffuse large B cell lymphoma (DLBCL) is a common and aggressive cancer caused by the malignant transformation of B cells. Although it has been established that the follicular helper T (Tfh) cells play a central role in B cell development, little information is available on their involvement in DLBCL pathogenesis. We studied the role of the peripheral Tfh equivalent, the CXCR5{sup +} CD4{sup +} T cells, in DLBCL. Data showed that compared to CXCR5{sup -} CD4{sup +} T cells, CXCR5{sup +} CD4{sup +} T cells were significantly more effective at promoting the proliferation as well as inhibiting the apoptosis ofmore » primary autologous DLBCL tumor cells. Surprisingly, we found that at equal cell numbers, CXCR5{sup +} CD4{sup +} T cells in DLBCL patients secreted significantly less interleukin (IL)-21 than CXCR5{sup -} CD4{sup +} T cells, while the level of IL-10 secretion was significant elevated in the CXCR5{sup +} compartment compared to the CXCR5{sup -} compartment. Neutralization of IL-10 in the primary DLBCL-CXCR5{sup +} CD4{sup +} T cell coculture compromised the CXCR5{sup +} CD4{sup +} T cell-mediated pro-tumor effects, in a manner that was dependent on the concentration of anti-IL-10 antibodies. The CXCR5{sup +} compartment also contained significantly lower frequencies of cytotoxic CD4{sup +} T cells than the CXCR5{sup -} compartment. In conclusion, our investigations discovered a previously unknown pro-tumor role of CXCR5-expressing circulating CD4{sup +} T cells, which assisted the survival and proliferation of primary DLBCL cells through IL-10. - Highlights: • We studied the role of the peripheral Tfh in DLBCL. • Tfh were effective at promoting the proliferation of primary DLBCL tumor cells. • Tfh were effective at inhibiting the apoptosis of primary DLBCL tumor cells. • IL-10 secretion in Tfh was significant elevated in DLBCL. • Neutralization of IL-10 compromised Tfh-mediated pro-tumor effects.« less

Selective CD28 blockade attenuates CTLA-4–dependent CD8+ memory T cell effector function and prolongs graft survival

PubMed Central

Liu, Danya; Badell, I. Raul; Ford, Mandy L.

2018-01-01

Memory T cells pose a significant problem to successful therapeutic control of unwanted immune responses during autoimmunity and transplantation, as they are differentially controlled by cosignaling receptors such as CD28 and CTLA-4. Treatment with abatacept and belatacept impede CD28 signaling by binding to CD80 and CD86, but they also have the unintended consequence of blocking the ligands for CTLA-4, a process that may inadvertently boost effector responses. Here, we show that a potentially novel anti-CD28 domain antibody (dAb) that selectively blocks CD28 but preserves CTLA-4 coinhibition confers improved allograft survival in sensitized recipients as compared with CTLA-4 Ig. However, both CTLA-4 Ig and anti-CD28 dAb similarly and significantly reduced the accumulation of donor-reactive CD8+ memory T cells, demonstrating that regulation of the expansion of CD8+ memory T cell populations is controlled in part by CD28 signals and is not significantly impacted by CTLA-4. In contrast, selective CD28 blockade was superior to CTLA-4 Ig in inhibiting IFN-γ, TNF, and IL-2 production by CD8+ memory T cells, which in turn resulted in reduced recruitment of innate CD11b+ monocytes into allografts. Importantly, this superiority was CTLA-4 dependent, demonstrating that effector function of CD8+ memory T cells is regulated by the balance of CD28 and CTLA-4 signaling. PMID:29321374

Increased CD127+ and decreased CD57+ T cell expression levels in HIV-infected patients on NRTI-sparing regimens.

PubMed

Gonzalez-Serna, A; Ferrando-Martinez, S; Tarancon-Diez, L; De Pablo-Bernal, R S; Dominguez-Molina, B; Jiménez, J L; Muñoz-Fernández, M Á; Leal, M; Ruiz-Mateos, E

2017-12-20

NRTIs-sparing regimens exert favourable profiles on T-cell homeostasis associated parameters. Our aim was to analyze the effect of NRTIs sparing regimen (NRTI-sparing-cART) vs NRTIs-containing regimen (NRTI-cART), on T-cell homeostasis associated parameters in naive HIV-infected patients. Biomarkers of cell survival (CD127) and replicative senescence (CD57), were measured by multiparametric flow cytometry for T-cell phenotyping on peripheral blood mononuclear cells (PBMCs) samples just before (baseline) and after 48 weeks of undetectable viral load in patients on NRTI-sparing-cART (N = 13) and NRTI-cART (N = 14). After 48 weeks a subgroup of patients (n = 5) on NRTI-cART switched to NRTI-sparing-cART for another additional 48 weeks. In vitro assays were performed on PBMCs from HIV-uninfected healthy donors exposed or not to HIV. To analyze the independent factors associated with type of cART bivariate and stepwise multivariate analysis were performed after adjusting for basal CD4+, CD8+ and nadir CD4+ T-cell counts. After 48 weeks of a NRTI-sparing-cART vs NRTI-cART patients have higher effector memory (EM) CD4+ CD127+ T-cell levels, lower EM CD4+ CD57+ T-cell levels, higher CD8+ CD127+ T-cell levels, lower CD8+ CD57+ T-cell levels and higher memory CD8+ T-cell levels. This effect was confirmed in the subgroup of patients who switched to NRTI-sparing-cART. In vitro assays confirmed that the deleterious effect of a NRTIs-containing regimen was due to NRTIs. The implementation of NRTI-sparing regimens, with a favourable profile in CD127 and CD57 T-cell expression, could benefit cART-patients. These results could have potential implications in a decrease in the number of Non-AIDS events.

RGC-32 is a novel regulator of the T-lymphocyte cell cycle.

PubMed

Tegla, Cosmin A; Cudrici, Cornelia D; Nguyen, Vinh; Danoff, Jacob; Kruszewski, Adam M; Boodhoo, Dallas; Mekala, Armugam P; Vlaicu, Sonia I; Chen, Ching; Rus, Violeta; Badea, Tudor C; Rus, Horea

2015-06-01

We have previously shown that RGC-32 is involved in cell cycle regulation in vitro. To define the in vivo role of RGC-32, we generated RGC-32 knockout mice. These mice developed normally and did not spontaneously develop overt tumors. To assess the effect of RGC-32 deficiency on cell cycle activation in T cells, we determined the proliferative rates of CD4(+) and CD8(+) T cells from the spleens of RGC-32(-/-) mice, as compared to wild-type (WT, RGC-32(+/+)) control mice. After stimulation with anti-CD3/anti-CD28, CD4(+) T cells from RGC-32(-/-) mice displayed a significant increase in [(3)H]-thymidine incorporation when compared to WT mice. In addition, both CD4(+) and CD8(+) T cells from RGC-32(-/-) mice displayed a significant increase in the proportion of proliferating Ki67(+) cells, indicating that in T cells, RGC-32 has an inhibitory effect on cell cycle activation induced by T-cell receptor/CD28 engagement. Furthermore, Akt and FOXO1 phosphorylation induced in stimulated CD4(+) T-cells from RGC-32(-/-) mice were significantly higher, indicating that RGC-32 inhibits cell cycle activation by suppressing FOXO1 activation. We also found that IL-2 mRNA and protein expression were significantly increased in RGC-32(-/-) CD4(+) T cells when compared to RGC-32(+/+) CD4(+) T cells. In addition, the effect of RGC-32 on the cell cycle and IL-2 expression was inhibited by pretreatment of the samples with LY294002, indicating a role for phosphatidylinositol 3-kinase (PI3K). Thus, RGC-32 is involved in controlling the cell cycle of T cells in vivo, and this effect is mediated by IL-2 in a PI3K-dependent fashion. Copyright © 2015 Elsevier Inc. All rights reserved.

IL-4 and IL-13 mediated down-regulation of CD8 expression levels can dampen anti-viral CD8⁺ T cell avidity following HIV-1 recombinant pox viral vaccination.

PubMed

Wijesundara, Danushka K; Jackson, Ronald J; Tscharke, David C; Ranasinghe, Charani

2013-09-23

We have shown that mucosal HIV-1 recombinant pox viral vaccination can induce high, avidity HIV-specific CD8(+) T cells with reduced interleukin (IL)-4 and IL-13 expression compared to, systemic vaccine delivery. In the current study how these cytokines act to regulate anti-viral CD8(+) T, cell avidity following HIV-1 recombinant pox viral prime-boost vaccination was investigated. Out of a panel of T cell avidity markers tested, only CD8 expression levels were found to be enhanced on, KdGag197-205 (HIV)-specific CD8(+) T cells obtained from IL-13(-/-), IL-4(-/-) and signal transducer and, activator of transcription of 6 (STAT6)(-/-) mice compared to wild-type (WT) controls following, vaccination. Elevated CD8 expression levels in this instance also correlated with polyfunctionality, (interferon (IFN)-γ, tumour necorsis factor (TNF)-α and IL-2 production) and the avidity of HIVspecific CD8(+) T cells. Furthermore, mucosal vaccination and vaccination with the novel adjuvanted IL-13 inhibitor (i.e. IL-13Rα2) vaccines significantly enhanced CD8 expression levels on HIV-specific CD8(+), T cells, which correlated with avidity. Using anti-CD8 antibodies that blocked CD8 availability on CD8(+), T cells, it was established that CD8 played an important role in increasing HIV-specific CD8(+) T cell avidity and polyfunctionality in IL-4(-/-), IL-13(-/-) and STAT6(-/-) mice compared to WT controls, following vaccination. Collectively, our data demonstrate that IL-4 and IL-13 dampen CD8 expression levels on anti-viral CD8(+) T cells, which can down-regulate anti-viral CD8(+) T cell avidity and, polyfunctionality following HIV-1 recombinant pox viral vaccination. These findings can be exploited to, design more efficacious vaccines not only against HIV-1, but many chronic infections where high, avidity CD8(+) T cells help protection. Copyright © 2013 Elsevier Ltd. All rights reserved.

CD147 blockade as a potential and novel treatment of graft rejection

PubMed Central

Luan, Jing; Zhao, Yu; Zhang, Yang; Miao, Jinlin; Li, Jia; Chen, Zhi-Nan; Zhu, Ping

2017-01-01

Cluster of differentiation (CD)147 is highly involved in the T cell activation process. High CD147 expression is observed on the surfaces of activated T cells, particularly CD4+ T cells. In organ transplantation, it is important to prevent graft rejection resulting from the excessive activation of T cells, particularly CD4+ T cells, which exhibit a key role in amplifying the immune response. The present study aimed to investigate the effects of CD147 blockade in vitro and in vivo and used a transplant rejection system to assess the feasibility of utilizing CD147 antibody-based immunosuppressant drugs for the treatment of graft rejection. The effects of CD147 antibodies were evaluated on lymphocyte proliferation stimulated by phytohemagglutinin or CD3/CD28 magnetic beads and in a one-way mixed lymphocyte reaction (MLR) system in vitro. For the in vivo analysis, an allogeneic skin transplantation mouse model was used. CD147 antibodies were effective against lymphocytes, particularly CD4+T lymphocytes, and were additionally effective in the one-way MLR system. In the allogeneic skin transplantation mouse model, the survival of transplanted skin was extended in the CD147 antibody-treated group. Furthermore, the level of inflammatory cell infiltration in transplanted skin was reduced. CD147 blockade decreased the serum levels of interleukin (IL)-17 and the proportions of peripheral blood CD4+ and CD8+ memory T cells. The data demonstrated that CD147 blockade suppressed skin graft rejection, primarily by suppressing CD4+T and memory T cell proliferation, indicating that CD147 exhibits great potential as a target of immunosuppressant drugs. PMID:28849101

Scrutinizing the Expression and Blockade of Inhibitory Molecules Expressed on T Cells from Acute Myeloid Leukemia Patients.

PubMed

Abdolmaleki, Mohsen; Mojtabavi, Nazanin; Zavvar, Mahdi; Vaezi, Mohammad; Noorbakhsh, Farshid; Nicknam, Mohammad Hossein

2018-06-01

T cell exhaustion is an immunosuppressive mechanism which occurs in chronic viral infections, solid tumors and hematologic malignancies. Exhausted T cell has increased the expression of inhibitory receptors, and functional impairment. In this study, we investigated the expression from some of those inhibitory receptors being Programmed death 1 (PD-1), T cell immunoglobulin and mucin domain containing molecules 3 (TIM-3) and CD244 on T cells from Iranian acute myeloid leukemia (AML) patients. Peripheral blood samples were collected from Iranian newly diagnosed AML patients and flow cytometric analysis was accomplished for cell surface expression of PD-1, TIM-3, and CD244 on T lymphocytes. Functionality and proliferation assay were done in the presence of anti-PD-1 and anti-CD244 blocking antibodies. Immunophenotyping of T cells showed a significant increase of PD-1 and CD244 expression on CD4+ and CD8+ T cells of AML patients. Whereas blockade of PD1 and CD244 increased the proliferation of CD4+ and CD8+ T lymphocytes of AML patients but IFN-γ production was not significantly increased. In conclusion, our data indicate that CD4+ and CD8+ T cells from AML patients appeared to be exhausted and blockade of some immune checkpoints can improve the proliferation of those cells.

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

CD4 T cell-mediated masking effects of the immunogenicity of tumor-associated antigens are qualitatively and quantitatively different depending on the individual antigens.

PubMed

Okano, Shinji; Matsumoto, Yoshihiro; Yoshiya, Shohei; Yamashita, Yo-ichi; Harimoto, Norifumi; Ikegami, Toru; Shirabe, Ken; Harada, Mamoru; Yoshikai, Yasunobu; Maehara, Yoshihiko

2013-01-01

The use of cancer immunotherapy as part of multidisciplinary therapies for cancer is a promising strategy for the cure of advanced cancer patients. In cancer immunotherapy, the effective priming of tumor-associated antigen (TAA)-specific CD8+ T cells is essential, and therefore, the appropriate selection of the best peptide for targeting the cancer is a most important concern. One criticism in the selection of a TAA is the immunogenicity of the TAA, the vaccination of which effectively elicits clinical responses. However, the critical basic immunological factors that affect the differences in the immunogenicity of TAAs remain to be elucidated. Here we found that CD4 T-cell responses suppressed the immunogenicity of the concomitant TAA in a murine melanoma model in which intratumoral activated dendritic therapy (ITADT) was used for treatment of the established cancer, and we observed that the antitumor effects were largely dependent on the CD8 T-cell response. CD4 T-cell depletion simply enhanced the tyrosinase-related protein (TRP)-2(180-188) peptide-specific cytotoxic T-cell (CTL) responses, and CD4 T-cell depletion provided immunogenicity for mgp100(25-33) peptide, to which a CTL response could not be detected at all in CD4 T-cell-intact mice in the early therapeutic phase. Further, the mgp100(25-33) peptide-specific CTL response again became undetectable after the recovery of CD4 T cells in previously CD4-depleted, tumor-eradicated mice, whereas the TRP-2(180-188) peptide-specific CTL response was still much stronger in CD4-depleted mice than in CD4-intact mice. These findings suggest that the CD4 T cell-mediated masking effects of the immunogenicity of tumor-associated antigens are qualitatively and quantitatively different depending on the individual antigens.

Recognition of prostate-specific antigenic peptide determinants by human CD4 and CD8 T cells.

PubMed

Corman, J M; Sercarz, E E; Nanda, N K

1998-11-01

It is now becoming accepted that one is not tolerant to all the determinants of self proteins: the T cell repertoire directed to some sequences in self proteins is intact and can be activated. When a self protein is exclusively expressed by tumour cells, the T cell repertoire directed to the particular self antigen can potentially be activated to attack the tumour: this would amount to induction of a beneficial autoimmune response. Prostate cancer offers a unique opportunity for activation of a tumour-specific immune response owing to the exclusive synthesis of prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSM) by prostatic tissue and prostate tumour cells. In this study we examine the CD4 and CD8 T cell repertoires specific for peptides of PSA and PSM in normal human male individuals, using short-term, peptide antigen-driven CD4 and CD8 T cell lines. We show that short-term, CD4 T cell lines derived from six HLA-DR4 individuals showed strong proliferative responses to six of 10 tested peptides of PSA, selected as to contain a DR4 binding motif. Short-term, CD8 T cell lines from three HLA-A1 individuals showed specific cytolytic activity for autologous targets loaded with five of five tested peptides of PSA and PSM, selected to possess an HLA-A1 binding motif. One of the peptides chosen is termed a 'dual-motif' peptide, as it encodes determinants for both CD4 and CD8 T cells. These results, indicating the existence of CD4 and CD8 T cells against determinants of the self proteins, PSA and PSM, in healthy male individuals reveal the potential of the T cell repertoire from the typical prostate cancer patient to eradicate prostate tumours upon being appropriately activated.

CXCL16 and CXCR6 are upregulated in psoriasis and mediate cutaneous recruitment of human CD8+ T cells.

PubMed

Günther, Claudia; Carballido-Perrig, Nicole; Kaesler, Susanne; Carballido, José M; Biedermann, Tilo

2012-03-01

Psoriatic skin lesions are characterized by an inflammatory infiltrate, consisting of dendritic cells, monocytes, and both CD4(+) and CD8(+) T lymphocytes. Although the chemokines involved in the migration of CD4(+) T cells into psoriatic skin are well characterized, those regulating CD8(+) T-cell recruitment are less understood. We found that the percentages of peripheral blood CD8(+) T cells expressing CXCR6 were higher in psoriatic patients than in healthy or atopic individuals. In addition, CXCR6 expression in psoriatic patients was more abundant in the CD8(+) than in the CD4(+) T-cell compartment. CXCR6 mRNA expression was also stronger in skin CD8(+) T cells than in the corresponding blood-derived counterparts. Immunofluorescence analysis revealed profound upregulation of the CXCR6 ligand CXCL16 by monocytes, keratinocytes, and dendritic cells in psoriatic skin compared with healthy or atopic dermatitis skin. In line with this, CXCR6(+) CD8(+) T cells also were most prevalent in psoriatic skin. Furthermore, CXCL16 induced Ca(2+) influx and chemotactic migration of psoriatic skin-derived CD8(+) T cells in vitro. Most importantly, CXCL16 potently recruited human CD8(+) T cells to human skin grafts previously transplanted onto SCID mice in vivo. These investigations indicate that CXCL16-CXCR6 interactions mediate homing of CD8(+) T cells into human skin, and thereby contribute to psoriasis pathogenesis.

Differential endocytosis of CD4 in lymphocytic and nonlymphocytic cells

PubMed Central

1991-01-01

The endocytosis of the T cell differentiation antigen CD4 has been investigated in CD4-transfected HeLa cells, the promyelocytic HL-60 cell line, and in a number of leukemia- or lymphoma-derived T cell lines. CD4 internalization was followed using radioiodinated antibodies in an acid-elution endocytosis assay, or by covalently modifying cell surface proteins with biotin and analyzing CD4 distributions by immunoprecipitation; both approaches gave equivalent results. The assays demonstrated that in transfected HeLa cells and in HL-60 cells CD4 was constitutively internalized and recycled in the absence of ligand. Immunogold labeling and electron microscopy demonstrated that CD4 enters cells through coated pits. In contrast to the nonlymphocytic cells, T cell lines showed very little endocytosis of CD4. Measurements of fluid phase endocytosis and morphometric analysis of the endosome compartment indicated that the endocytic capacities of HeLa and lymphoid cells are equivalent and suggested that the low level of CD4 uptake in lymphocytic cells is due to exclusion of CD4 from coated pits. This conclusion was supported by experiments using truncated CD4 molecules, lacking the bulk of the cytoplasmic domain, which were internalized equally efficiently in both transfected lymphocytes and HeLa cells. Together, these results indicate that the cytoplasmic domain of CD4 mediates the different interactions with the endocytic apparatus in lymphoid and nonlymphoid cells. We suggest that the CD4- associated lymphocyte-specific protein tyrosine kinase p56lck may be involved in preventing CD4 endocytosis in T cells. PMID:1900077

MIF: a down-regulator of early T cell-dependent IFN-γ responses in Plasmodium chabaudi adami (DK) infected mice

PubMed Central

Tshikudi Malu, Diane; Bélanger, Benoit; Desautels, François; Kelendji, Karine; Dalko, Esther; Sanchez-Dardon, Jaime; Leng, Lin; Bucala, Richard; Satoskar, Abhay; Scorza, Tatiana

2012-01-01

Neutralization of macrophage migration inhibitory factor (MIF) increases anti-tumor cytotoxic T cell responses in vivo and IFN-γ responses in vitro, suggesting a plausible regulatory role for MIF in T cell activation. Considering that IFN-γ production by CD4+ T cells is pivotal to resolve murine malaria and that secretion of MIF is induced by Plasmodium chabaudi adami parasites, we investigated the effect of MIF deficiency on the infection with this pathogen. Infections with P.c. adami DK parasites were more efficiently controlled in MIF-neutralized and MIF-deficient (KO) BALB/c mice. The reduction in parasitemia was associated with reduced production of IL-4 by non-T/non-B cells throughout patent infection. At day 4 post-infection, higher numbers of activated CD4+ cells were measured in MIF KO mice, which secreted more IFN-γ, less IL-4 and less IL-10 than CD4+ T cells from WT mice. Enhanced IFN-γ and decreased IL-4 responses also were measured in MIF KO CD4+ T cells stimulated with or without IL-12 and anti-IL-4 blocking antibody to induce Th1 polarization. However, MIF KO CD4+ T cells efficiently acquired a Th2 phenotype when stimulated in the presence of IL-4 and anti-IL-12 antibody, indicating normal responsiveness to IL-4/STAT6 signaling. These results suggest that by promoting IL-4 responses in cells other than T/B cells during early P.c. adami infection, MIF decreases IFN-γ secretion in CD4+ T cells and in addition, has the intrinsic ability to render CD4+ T cells less capable of acquiring a robust Th1 phenotype when stimulated in the presence of IL-12. PMID:21518974

Reduction in CD4 central memory T-cell subset in costimulation modulator abatacept-treated patients with recent-onset type 1 diabetes is associated with slower C-peptide decline.

PubMed

Orban, Tihamer; Beam, Craig A; Xu, Ping; Moore, Keith; Jiang, Qi; Deng, Jun; Muller, Sarah; Gottlieb, Peter; Spain, Lisa; Peakman, Mark

2014-10-01

We previously reported that continuous 24-month costimulation blockade by abatacept significantly slows the decline of β-cell function after diagnosis of type 1 diabetes. In a mechanistic extension of that study, we evaluated peripheral blood immune cell subsets (CD4, CD8-naive, memory and activated subsets, myeloid and plasmacytoid dendritic cells, monocytes, B lymphocytes, CD4(+)CD25(high) regulatory T cells, and invariant NK T cells) by flow cytometry at baseline and 3, 6, 12, 24, and 30 months after treatment initiation to discover biomarkers of therapeutic effect. Using multivariable analysis and lagging of longitudinally measured variables, we made the novel observation in the placebo group that an increase in central memory (CM) CD4 T cells (CD4(+)CD45R0(+)CD62L(+)) during a preceding visit was significantly associated with C-peptide decline at the subsequent visit. These changes were significantly affected by abatacept treatment, which drove the peripheral contraction of CM CD4 T cells and the expansion of naive (CD45R0(-)CD62L(+)) CD4 T cells in association with a significantly slower rate of C-peptide decline. The findings show that the quantification of CM CD4 T cells can provide a surrogate immune marker for C-peptide decline after the diagnosis of type 1 diabetes and that costimulation blockade may exert its beneficial therapeutic effect via modulation of this subset. © 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

The role of 9-O-acetylated ganglioside D3 (CD60) and α4β1 (CD49d) expression in predicting the survival of patients with Sézary syndrome

PubMed Central

Scala, Enrico; Abeni, Damiano; Pomponi, Debora; Narducci, Maria Grazia; Lombardo, Giuseppe Alfonso; Mari, Adriano; Frontani, Marina; Picchio, Maria Cristina; Pilla, Maria Antonietta; Caprini, Elisabetta; Russo, Giandomenico

2010-01-01

Background Sézary syndrome is a rare and very aggressive leukemic variant of cutaneous T-cell lymphoma characterized by extensive skin involvement and a malignant circulating CD4+ T-cell clone which homes to the skin, over-expresses CD60, and lacks CD7, CD26 and CD49d. So far prognostic markers in this disease are limited to treatment with systemic steroids, age, serum lactate dehydrogenase, and a white blood cell count of 20×109/L or higher: no other biological marker with prognostic value, especially related to malignant cells, has been described. Design and Methods We used flow activated cell sorting analysis to compare the distribution of the T-cell receptor-Vβ repertoire and several surface molecules (CD7, CD26, CD49d and CD60) within the circulating CD4+ T-cell population in 62 patients with Sézary syndrome, 180 with mycosis fungoides, 6 with B-cell lymphomas, and 19 with chronic eczema. We calculated the 5-year overall survival of patients with Sézary syndrome after first hospital admission using Kaplan–Meier product–limit estimates and hazard ratios from the Cox proportional hazards model. Results We found that both higher number of CD60+ and lower number of CD49d+ cells within circulating CD4+ T cells at disease presentation were significantly associated with a lower probability of survival. An exceedingly high risk of death was observed for patients with a combination of a high proportion of CD4+CD60+ cells (≥ 0.5×109/L) and low proportion of CD4+CD49d+ cells (<0.5×109/L) (hazard ratio = 12.303, 95% confidence interval 1.5–95.9; P<0.02). In addition, a skewed usage of T-cell receptor-Vβ subfamilies was observed in the circulating T-cell clone for 61.9% of all patients with Sézary syndrome, T-cell receptor-Vβ 2 and 5.1 subfamilies being the most frequently represented (42.8%), followed by T-cell receptor-Vβ 12 and 13.1. Conclusions In this study we showed that up-regulation of CD60 and down-regulation of CD49d on circulating CD4+ T cells are two useful markers for predicting a very poor outcome in patients with Sézary syndrome. PMID:20663947

Transient expansion of activated CD8+ T cells characterizes tuberculosis-associated immune reconstitution inflammatory syndrome in patients with HIV: a case control study

PubMed Central

2013-01-01

Background CD4+ T cell activation indicators have been reported to be a common phenomenon underlying diverse manifestations of immune reconstitution inflammatory syndrome (IRIS). However, we have found that a high frequency of circulating CD8+ T cells is a specific risk factor for mycobacterial IRIS. Therefore, we investigated whether CD8+ T cells from patients who develop TB IRIS were specifically activated. Methods We obtained PBMCs from HIV+ patients prior to and 4, 8, 12, 24, 52 and 104 weeks after initiating antiretroviral therapy. CD38 and HLADR expression on naive, central memory and effector memory CD8+ and CD4+ T cells were determined by flow cytometry. Absolute counts and frequencies of CD8+ T cell subsets were compared between patients who developed TB IRIS, who developed other IRIS forms and who remained IRIS-free. Results TB IRIS patients showed significantly higher counts of naive CD8+ T cells than the other groups at most time points, with a contraction of the effector memory subpopulation occurring later in the follow-up period. Activated (CD38+ HLADR+) CD8+ T cells from all groups decreased with treatment but transiently peaked in TB IRIS patients. This increase was due to an increase in activated naive CD8+ T cell counts during IRIS. Additionally, the CD8+ T cell subpopulations of TB IRIS patients expressed HLADR without CD38 more frequently and expressed CD38 without HLADR less frequently than cells from other groups. Conclusions CD8+ T cell activation is specifically relevant to TB IRIS. Different IRIS forms may involve different alterations in T cell subsets, suggesting different underlying inflammatory processes. PMID:23688318

Circulating rotavirus-specific T cells have a poor functional profile

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

Parra, Miguel; Herrera, Daniel; Jácome, María Fernanda

Frequencies of circulating T cells producing IFN-γ, TNF-α, and IL-2, and percentages of T cells proliferating after stimulation with rotavirus (RV), tetanus toxoid, and influenza were evaluated in PBMC derived from healthy adults and children. In addition, the potential anergic state of RV-specific T cells was analyzed by stimulation of PBMC with RV antigen in the presence of three anergy inhibitors (rIL-2, rIL-12, or DGKα-i). The quality and magnitude of RV-T cell responses were significantly lower than those of tetanus toxoid and influenza antigens. RV-CD4 T cell response was enriched in monofunctional IFN-γ{sup +} cells, while influenza-CD4 and tetanus toxoid-CD4more » T cell responses were enriched in multifunctional T cells. Moreover, rIL-2 – unlike rIL-12 or DGKα-i – increased the frequencies of RV-CD4 TNF-α{sup +}, CD4 IFN-γ{sup +}, and CD8 IFN-γ{sup +} cells. Thus, circulating RV-T cells seem to have a relatively poor functional profile that may be partially reversed in vitro by the addition of rIL-2. - Highlights: • The quality and magnitude of circulating RV-T cell responses are relatively poor. • Circulating RV-CD4 T cells are enriched in monofunctional IFN-γ+ cells. • Treatment with rIL-2 increased the frequencies of cytokine secreting RV-T cells.« less

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

PubMed Central

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

2011-01-01

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

Virus-induced dysfunction of CD4+CD25+ T cells in patients with HTLV-I-associated neuroimmunological disease.

PubMed

Yamano, Yoshihisa; Takenouchi, Norihiro; Li, Hong-Chuan; Tomaru, Utano; Yao, Karen; Grant, Christian W; Maric, Dragan A; Jacobson, Steven

2005-05-01

CD4(+)CD25(+) Tregs are important in the maintenance of immunological self tolerance and in the prevention of autoimmune diseases. As the CD4(+)CD25(+) T cell population in patients with human T cell lymphotropic virus type I-associated (HTLV-I-associated) myelopathy/tropical spastic paraparesis (HAM/TSP) has been shown to be a major reservoir for this virus, it was of interest to determine whether the frequency and function of CD4(+)CD25(+) Tregs in HAM/TSP patients might be affected. In these cells, both mRNA and protein expression of the forkhead transcription factor Foxp3, a specific marker of Tregs, were lower than those in CD4(+)CD25(+) T cells from healthy individuals. The virus-encoded transactivating HTLV-I tax gene was demonstrated to have a direct inhibitory effect on Foxp3 expression and function of CD4(+)CD25(+) T cells. This is the first report to our knowledge demonstrating the role of a specific viral gene product (HTLV-I Tax) on the expression of genes associated with Tregs (in particular, foxp3) resulting in inhibition of Treg function. These results suggest that direct human retroviral infection of CD4(+)CD25(+) T cells may be associated with the pathogenesis of HTLV-I-associated neurologic disease.

Toll like Receptor 2 engagement on CD4+ T cells promotes TH9 differentiation and function.

PubMed

Karim, Ahmad Faisal; Reba, Scott M; Li, Qing; Boom, W Henry; Rojas, Roxana E

2017-09-01

We have recently demonstrated that mycobacterial ligands engage Toll like receptor 2 (TLR2) on CD4 + T cells and up-regulate T-cell receptor (TCR) triggered Th1 responses in vitro and in vivo. To better understand the role of T-cell expressed TLR2 on CD4 + T-cell differentiation and function, we conducted a gene expression analysis of murine naïve CD4 + T-cells stimulated in the presence or absence of TLR2 co-stimulation. Unexpectedly, naïve CD4 + T-cells co-stimulated via TLR2 showed a significant up-regulation of Il9 mRNA compared to cells co-stimulated via CD28. Under TH9 differentiation, we observed up-regulation of TH9 differentiation, evidenced by increases in both percent of IL-9 secreting cells and IL-9 in culture supernatants in the presence of TLR2 agonist both in polyclonal and Ag85B cognate peptide specific stimulations. Under non-polarizing conditions, TLR2 engagement on CD4 + T-cells had minimal effect on IL-9 secretion and TH9 differentiation, likely due to a prominent effect of TLR2 signaling on IFN-γ secretion and TH1 differentiation. We also report that, TLR2 signaling in CD4 + T cells increased expression of transcription factors BATF and PU.1, known to positively regulate TH9 differentiation. These results reveal a novel role of T-cell expressed TLR2 in enhancing the differentiation and function of TH9 T cells. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Transcriptional network profile on synovial fluid T cells in psoriatic arthritis.

PubMed

Fiocco, Ugo; Martini, Veronica; Accordi, Benedetta; Caso, Francesco; Costa, Luisa; Oliviero, Francesca; Scanu, Anna; Facco, Monica; Boso, Daniele; Gatto, Mariele; Felicetti, Mara; Frallonardo, Paola; Ramonda, Roberta; Piva, Lucia; Zambello, Renato; Agostini, Carlo; Scarpa, Raffaele; Basso, Giuseppe; Semenzato, Gianpietro; Dayer, Jean-Michel; Punzi, Leonardo; Doria, Andrea

2015-09-01

The objective of the study was to quantify the transcriptional profile, as the main T cell lineage-transcription factors on synovial fluid (SF) T cells, in relation to SF cytokines and T cell frequencies (%) of psoriatic arthritis (PsA) patients. Reverse phase protein array was employed to identify interleukin (IL)-23Rp19-, FOXP3- and related orphan receptor gamma T (RORγt)- protein and Janus associated tyrosine kinases 1 (JAK1), signal transducer and activator and transcription 1 (STAT1), STAT3 and STAT5 phosphoproteins in total T cell lysates from SF of PsA patients. IL-1β, IL-2, IL-6, IL-21 and interferon (INF)-γ were measured using a multiplex bead immunoassay in SF from PsA patients and peripheral blood (PB) from healthy controls (HC). Frequencies of CD4(+)CD25(-), CD4(+)CD25(high) FOXP3(+) and CD4(+)CD25(high) CD127(low) Treg, and either mean fluorescence intensity (MFI) of FOXP3(+) on CD4(+) Treg or MFI of classic IL-6 receptor (IL-6R) α expression on CD4(+)CD25(-) helper/effector T cells (Th/eff) and Treg cells, were quantified in SF of PsA patients and in PB from HC by flow cytometry (FC). In PsA SF samples, IL-2, IL-21 and IFN-γ were not detectable, whereas IL-6 and IL-1β levels were higher than in SF of non-inflammatory osteoarthritis patients. Higher levels of IL-23R-, FOXP3- and RORγt proteins and JAK1, STAT1, STAT3 and STAT5 were found in total T cells from SF of PsA patients compared with PB from HC. Direct correlations between JAK1 Y1022/Y1023 and STAT5 Y694, and STAT3 Y705 and IL6, were found in SF of PsA patients. Increased proportion of CD4(+)CD25(high) FOXP3(+) and CD4(+)CD25(high) CD127(low) Treg cells and brighter MFI of IL-6Rα were observed both on CD4(+)CD25(high)- and CD4(+)CD25(-) T cells in PsA SF. The study showed a distinctive JAK1/STAT3/STAT5 transcriptional network on T cells in the joint microenvironment, outlining the interplay of IL-6, IL-23, IL-1β and γC cytokines in the polarization and plasticity of Th17 and Treg cells, which might participate in the perpetuation of joint inflammation in PsA patients.

Homeostasis of naive and memory CD4+ T cells: IL-2 and IL-7 differentially regulate the balance between proliferation and Fas-mediated apoptosis.

PubMed

Jaleco, Sara; Swainson, Louise; Dardalhon, Valérie; Burjanadze, Maryam; Kinet, Sandrina; Taylor, Naomi

2003-07-01

Cytokines play a crucial role in the maintenance of polyclonal naive and memory T cell populations. It has previously been shown that ex vivo, the IL-7 cytokine induces the proliferation of naive recent thymic emigrants (RTE) isolated from umbilical cord blood but not mature adult-derived naive and memory human CD4(+) T cells. We find that the combination of IL-2 and IL-7 strongly promotes the proliferation of RTE, whereas adult CD4(+) T cells remain relatively unresponsive. Immunological activity is controlled by a balance between proliferation and apoptotic cell death. However, the relative contributions of IL-2 and IL-7 in regulating these processes in the absence of MHC/peptide signals are not known. Following exposure to either IL-2 or IL-7 alone, RTE, as well as mature naive and memory CD4(+) T cells, are rendered only minimally sensitive to Fas-mediated cell death. However, in the presence of the two cytokines, Fas engagement results in a high level of caspase-dependent apoptosis in both RTE as well as naive adult CD4(+) T cells. In contrast, equivalently treated memory CD4(+) T cells are significantly less sensitive to Fas-induced cell death. The increased susceptibility of RTE and naive CD4(+) T cells to Fas-induced apoptosis correlates with a significantly higher IL-2/IL-7-induced Fas expression on these T cell subsets than on memory CD4(+) T cells. Thus, IL-2 and IL-7 regulate homeostasis by modulating the equilibrium between proliferation and apoptotic cell death in RTE and mature naive and memory T cell subsets.

Regulation of allergic airway inflammation by adoptive transfer of CD4+ T cells preferentially producing IL-10.

PubMed

Matsuda, Masaya; Doi, Kana; Tsutsumi, Tatsuya; Fujii, Shinya; Kishima, Maki; Nishimura, Kazuma; Kuroda, Ikue; Tanahashi, Yu; Yuasa, Rino; Kinjo, Toshihiko; Kuramoto, Nobuyuki; Mizutani, Nobuaki; Nabe, Takeshi

2017-10-05

Anti-inflammatory pharmacotherapy for asthma has mainly depended on the inhalation of glucocorticoids, which non-specifically suppress immune responses. If the anti-inflammatory cytokine interleukin (IL)-10 can be induced by a specific antigen, asthmatic airway inflammation could be suppressed when individuals are exposed to the antigen. The purpose of this study was to develop cellular immunotherapeutics for atopic diseases using IL-10-producing CD4 + T cells. Spleen cells isolated from ovalbumin (OVA)-sensitized mice were cultured with the antigen, OVA and growth factors, IL-21, IL-27 and TGF-β for 7 days. After the 7-day culture, the CD4 + T cells were purified using a murine CD4 magnetic beads system. When the induced CD4 + T cells were stimulated by OVA in the presence of antigen-presenting cells, IL-10 was preferentially produced in vitro. When CD4 + T cells were adoptively transferred to OVA-sensitized mice followed by intratracheal OVA challenges, IL-10 was preferentially produced in the serum and bronchoalveolar lavage fluid in vivo. IL-10 production coincided with the inhibition of eosinophilic airway inflammation and epithelial mucus plugging. Most of the IL-10-producing CD4 + T cells were negative for Foxp3 and GATA-3, transcription factors of naturally occurring regulatory T cells and Th2 cells, respectively, but double positive for LAG-3 and CD49b, surface markers of inducible regulatory T cells, Tr1 cells. Collectively, most of the induced IL-10-producing CD4 + T cells could be Tr1 cells, which respond to the antigen to produce IL-10, and effectively suppressed allergic airway inflammation. The induced Tr1 cells may be useful for antigen-specific cellular immunotherapy for atopic diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

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

PubMed Central

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

2016-01-01

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

An epitope-specific DerG-PG70 LEAPS vaccine modulates T cell responses and suppresses arthritis progression in two related murine models of rheumatoid arthritis.

PubMed

Mikecz, Katalin; Glant, Tibor T; Markovics, Adrienn; Rosenthal, Kenneth S; Kurko, Julia; Carambula, Roy E; Cress, Steve; Steiner, Harold L; Zimmerman, Daniel H

2017-07-13

Rheumatoid arthritis (RA) is an autoimmune joint disease maintained by aberrant immune responses involving CD4+ T helper (Th)1 and Th17 cells. In this study, we tested the therapeutic efficacy of Ligand Epitope Antigen Presentation System (LEAPS™) vaccines in two Th1 cell-driven mouse models of RA, cartilage proteoglycan (PG)-induced arthritis (PGIA) and PG G1-domain-induced arthritis (GIA). The immunodominant PG peptide PG70 was attached to a DerG or J immune cell binding peptide, and the DerG-PG70 and J-PG70 LEAPS vaccines were administered to the mice after the onset of PGIA or GIA symptoms. As indicated by significant decreases in visual and histopathological scores of arthritis, the DerG-PG70 vaccine inhibited disease progression in both PGIA and GIA, while the J-PG70 vaccine was ineffective. Splenic CD4+ cells from DerG-PG70-treated mice were diminished in Th1 and Th17 populations but enriched in Th2 and regulatory T (Treg) cells. In vitro spleen cell-secreted and serum cytokines from DerG-PG70-treated mice demonstrated a shift from a pro-inflammatory to an anti-inflammatory/regulatory profile. DerG-PG70 peptide tetramers preferentially bound to CD4+ T-cells of GIA spleen cells. We conclude that the DerG-PG70 vaccine (now designated CEL-4000) exerts its therapeutic effect by interacting with CD4+ cells, which results in an antigen-specific down-modulation of pathogenic T-cell responses in both the PGIA and GIA models of RA. Future studies will need to determine the potential of LEAPS vaccination to provide disease suppression in patients with RA. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Combined influence of adjuvant therapy and interval after surgery on peripheral CD4+ T lymphocytes in patients with esophageal squamous cell carcinoma

PubMed Central

LING, YANG; FAN, LIEYING; DONG, CHUNLEI; ZHU, JING; LIU, YONGPING; NI, YAN; ZHU, CHANGTAI; ZHANG, CHANGSONG

2010-01-01

The aim of this study was to investigate possible differences in cellular immunity between chemo- and/or radiotherapy groups during a long interval after surgery in esophageal squamous cell carcinoma (ESCC) patients. Cellular immunity was assessed as peripheral lymphocyte subsets in response to chemotherapy (CT), radiotherapy (RT) and CT+RT by flow cytometric analysis. There were 139 blood samples obtained at different time points relative to surgery from 73 patients with ESCC. The changes in the absolute and relative proportions of lymphocyte phenotypes were significant among the adjuvant therapy groups. There were significant differences in the absolute counts of CD4+ and CD8+ T cells among the interval groups, and a lower CD4/CD8 ratio was found in patients following a prolonged interval. RT alone had a profound effect on the absolute counts of CD3+, CD4+ and CD8+ T cells compared with the other groups. CD4+ T cells exhibited a decreasing trend during a long interval, leading to a prolonged T-cell imbalance after surgery. Univariate analysis revealed that the interaction of the type of adjuvant therapy and the interval after surgery was correlated only with the percentage of CD4+ T cells. The percentage of CD4+ T cells can be used as an indicator of the cellular immunity after surgery in ESCC patients. However, natural killer cells consistently remained suppressed in ESCC patients following adjuvant therapy after surgery. These findings confirm an interaction between adjuvant therapy and the interval after surgery on peripheral CD4+ T cells, and implies that adjuvant therapy may have selective influence on the cellular immunity of ESCC patients after surgery. PMID:23136603

Collaboration between tumor-specific CD4+ T cells and B cells in anti-cancer immunity.

PubMed

Guy, Thomas V; Terry, Alexandra M; Bolton, Holly A; Hancock, David G; Zhu, Erhua; Brink, Robert; McGuire, Helen M; Shklovskaya, Elena; Fazekas de St. Groth, Barbara

2016-05-24

The role of B cells and antibodies in anti-tumor immunity is controversial, with both positive and negative effects reported in animal models and clinical studies. We developed a murine B16.F10 melanoma model to study the effects of collaboration between tumor-specific CD4+ T cells and B cells on tumor control. By incorporating T cell receptor transgenic T cells and B cell receptor isotype switching B cells, we were able to track the responses of tumor-reactive T and B cells and the development of anti-tumor antibodies in vivo. In the presence of tumor-specific B cells, the number of tumor-reactive CD4+ T cells was reduced in lymphoid tissues and the tumor itself, and this correlated with poor tumor control. B cells had little effect on the Th1 bias of the CD4+ T cell response, and the number of induced FoxP3+ regulatory cells (iTregs) generated from within the original naive CD4+ T cell inoculum was unrelated to the degree of B cell expansion. In response to CD4+ T cell help, B cells produced a range of isotype-switched anti-tumor antibodies, principally IgG1, IgG2a/c and IgG2b. In the absence of CD4+ T cells, B cells responded to agonistic anti-CD40 administration by switching to production of IgG2a/c and, to a lesser extent, IgG1, IgG3, IgA and IgE, which reduced the number of lung metastases after i.v. tumor inoculation but had no effect on the growth of subcutaneous tumors.

Polyfunctional response by ImmTAC (IMCgp100) redirected CD8+ and CD4+ T cells.

PubMed

Boudousquie, Caroline; Bossi, Giovanna; Hurst, Jacob M; Rygiel, Karolina A; Jakobsen, Bent K; Hassan, Namir J

2017-11-01

The success of immune system-based cancer therapies depends on a broad immune response engaging a range of effector cells and mechanisms. Immune mobilizing monoclonal T cell receptors (TCRs) against cancer (ImmTAC™ molecules: fusion proteins consisting of a soluble, affinity enhanced TCR and an anti-CD3 scFv antibody) were previously shown to redirect CD8 + and CD4 + T cells against tumours. Here we present evidence that IMCgp100 (ImmTAC recognizing a peptide derived from the melanoma-specific protein, gp100, presented by HLA-A*0201) efficiently redirects and activates effector and memory cells from both CD8 + and CD4 + repertoires. Using isolated subpopulations of T cells, we find that both terminally differentiated and effector memory CD8 + T cells redirected by IMCgp100 are potent killers of melanoma cells. Furthermore, CD4 + effector memory T cells elicit potent cytotoxic activity leading to melanoma cell killing upon redirection by IMCgp100. The majority of T cell subsets belonging to both the CD8 + and CD4 + repertoires secrete key pro-inflammatory cytokines (tumour necrosis factor-α, interferon-γ, interleukin-6) and chemokines (macrophage inflammatory protein-1α-β, interferon-γ-inducible protein-10, monocyte chemoattractant protein-1). At an individual cell level, IMCgp100-redirected T cells display a polyfunctional phenotype, which is a hallmark of a potent anti-cancer response. This study demonstrates that IMCgp100 induces broad immune responses that extend beyond the induction of CD8 + T cell-mediated cytotoxicity. These findings are of particular importance because IMCgp100 is currently undergoing clinical trials as a single agent or in combination with check point inhibitors for patients with malignant melanoma. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd.

Acute and chronic T cell dynamics in the livers of simian immunodeficiency virus-infected macaques.

PubMed

Ahsan, Muhammad H; Gill, Amy F; Lackner, Andrew A; Veazey, Ronald S

2012-05-01

The mucosal immune system, particularly the gastrointestinal tract, is critically involved in the pathogenesis of human immunodeficiency virus (HIV) infection. Since the liver drains most of the substances coming from the intestinal tract, it may also play a role in the pathogenesis of HIV infection. Here we examined the percentages and absolute numbers of T cell subsets in the liver in normal and simian immunodeficiency virus (SIV)-infected macaques. Most of the T cells in the liver were CD8(+) memory cells, and most of these had an effector memory (CD95(+) CD28(-)) phenotype. CD4(+) T cells constituted approximately 20% of the liver T cell population, but the vast majority of these were also memory (CD95(+)) CCR5(+) cells, suggesting they were potential targets for viral infection. After SIV infection, CD4(+) T cells were markedly reduced, and increased proliferation and absolute numbers of CD8(+) T cells were detected in the liver. These data suggest that the liver is a major source of antigenic stimulation for promoting CD8(+) T cells and possibly a source for early CD4(+) T cell infection and destruction.

Acute and Chronic T Cell Dynamics in the Livers of Simian Immunodeficiency Virus-Infected Macaques

PubMed Central

Ahsan, Muhammad H.; Gill, Amy F.; Lackner, Andrew A.

2012-01-01

The mucosal immune system, particularly the gastrointestinal tract, is critically involved in the pathogenesis of human immunodeficiency virus (HIV) infection. Since the liver drains most of the substances coming from the intestinal tract, it may also play a role in the pathogenesis of HIV infection. Here we examined the percentages and absolute numbers of T cell subsets in the liver in normal and simian immunodeficiency virus (SIV)-infected macaques. Most of the T cells in the liver were CD8+ memory cells, and most of these had an effector memory (CD95+ CD28−) phenotype. CD4+ T cells constituted approximately 20% of the liver T cell population, but the vast majority of these were also memory (CD95+) CCR5+ cells, suggesting they were potential targets for viral infection. After SIV infection, CD4+ T cells were markedly reduced, and increased proliferation and absolute numbers of CD8+ T cells were detected in the liver. These data suggest that the liver is a major source of antigenic stimulation for promoting CD8+ T cells and possibly a source for early CD4+ T cell infection and destruction. PMID:22379078

Phase I clinical trial of costimulated, IL-4 polarized donor CD4+ T cells as augmentation of allogeneic hematopoietic cell transplantation.

PubMed

Fowler, Daniel H; Odom, Jeanne; Steinberg, Seth M; Chow, Catherine K; Foley, Jason; Kogan, Yelena; Hou, Jeannie; Gea-Banacloche, Juan; Sportes, Claude; Pavletic, Steven; Leitman, Susan; Read, Elizabeth J; Carter, Charles; Kolstad, Arne; Fox, Rebecca; Beatty, Gregory L; Vonderheide, Robert H; Levine, Bruce L; June, Carl H; Gress, Ronald E; Bishop, Michael R

2006-11-01

The primary objective of this clinical trial was to evaluate the safety, feasibility, and biologic effects of administering costimulated, interleukin (IL)-4 polarized donor CD4(+) T cells in the setting of HLA-matched sibling, T cell-replete allogeneic hematopoietic cell transplantation (HCT). Forty-seven subjects with hematologic malignancy received granulocyte colony-stimulating factor-mobilized allogeneic hematopoietic cell transplants and cyclosporine graft-versus-host disease (GVHD) prophylaxis after reduced intensity conditioning. Initial subjects received no additional cells (n = 19); subsequent subjects received additional donor CD4(+) T cells generated ex vivo by CD3/CD28 costimulation in medium containing IL-4 and IL-2 (administered day 1 after HCT at 5, 25, or 125 x 10(6) cells/kg). Studies after HCT included measurement of monocyte IL-1alpha and tumor necrosis factor alpha, detection of T cells with antitumor specificity, and characterization of T cell cytokine phenotype. The culture method generated donor CD4(+) T cells that secreted increased T helper 2 (Th2) cytokines and decreased T helper 1 (Th1) cytokines. Such Th2-like cells were administered without infusional or dose-limiting toxicity. The Th2 cohort had accelerated lymphocyte reconstitution; both cohorts had rapid hematopoietic recovery and alloengraftment. Acute GVHD and overall survival were similar in the Th2 and non-Th2 cohorts. Th2 cell recipients tended to have increased monocyte IL-1alpha and had increased tumor necrosis factor alpha secretion. CD8(+) T cells with antitumor specificity were observed in Th2 and non-Th2 cohorts. Post-transplantation T cells from Th2 cell recipients secreted IL-4 and IL-10 (Th2 cytokines) and IL-2 and interferon gamma (Th1 cytokines). Allograft augmentation with costimulated, IL-4-polarized donor CD4(+) T cells resulted in activated Th1, Th2, and inflammatory cytokine pathways without an apparent increase in GVHD.

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

Primary Murine CD4+ T Cells Fail to Acquire the Ability to Produce Effector Cytokines When Active Ras Is Present during Th1/Th2 Differentiation

PubMed Central

Janardhan, Sujit V.; Marks, Reinhard; Gajewski, Thomas F.

2014-01-01

Constitutive Ras signaling has been shown to augment IL-2 production, reverse anergy, and functionally replace many aspects of CD28 co-stimulation in CD4+ T cells. These data raise the possibility that introduction of active Ras into primary T cells might result in improved functionality in pathologic situations of T cell dysfunction, such as cancer or chronic viral infection. To test the biologic effects of active Ras in primary T cells, CD4+ T cells from Coxsackie-Adenovirus Receptor Transgenic mice were transduced with an adenovirus encoding active Ras. As expected, active Ras augmented IL-2 production in naive CD4+ T cells. However, when cells were cultured for 4 days under conditions to promote effector cell differentiation, active Ras inhibited the ability of CD4+ T cells to acquire a Th1 or Th2 effector cytokine profile. This differentiation defect was not due to deficient STAT4 or STAT6 activation by IL-12 or IL-4, respectively, nor was it associated with deficient induction of T-bet and GATA-3 expression. Impaired effector cytokine production in active Ras-transduced cells was associated with deficient demethylation of the IL-4 gene locus. Our results indicate that, despite augmenting acute activation of naïve T cells, constitutive Ras signaling inhibits the ability of CD4+ T cells to properly differentiate into Th1/Th2 effector cytokine-producing cells, in part by interfering with epigenetic modification of effector gene loci. Alternative strategies to potentiate Ras pathway signaling in T cells in a more regulated fashion should be considered as a therapeutic approach to improve immune responses in vivo. PMID:25397617

Hierarchy Low CD4+/CD8+ T-Cell Counts and IFN-γ Responses in HIV-1+ Individuals Correlate with Active TB and/or M.tb Co-Infection.

PubMed

Shao, Lingyun; Zhang, Xinyun; Gao, Yan; Xu, Yunya; Zhang, Shu; Yu, Shenglei; Weng, Xinhua; Shen, Hongbo; Chen, Zheng W; Jiang, Weimin; Zhang, Wenhong

2016-01-01

Detailed studies of correlation between HIV-M.tb co-infection and hierarchy declines of CD8+/CD4+ T-cell counts and IFN-γ responses have not been done. We conducted case-control studies to address this issue. 164 HIV-1-infected individuals comprised of HIV-1+ATB, HIV-1+LTB and HIV-1+TB- groups were evaluated. Immune phenotyping and complete blood count (CBC) were employed to measure CD4+ and CD8+ T-cell counts; T.SPOT.TB and intracellular cytokine staining (ICS) were utilized to detect ESAT6, CFP10 or PPD-specific IFN-γ responses. There were significant differences in median CD4+ T-cell counts between HIV-1+ATB (164/μL), HIV-1+LTB (447/μL) and HIV-1+TB- (329/μL) groups. Hierarchy low CD4+ T-cell counts (<200/μL, 200-500/μL, >500/μL) were correlated significantly with active TB but not M.tb co-infection. Interestingly, hierarchy low CD8+ T-cell counts were not only associated significantly with active TB but also with M.tb co-infection (P<0.001). Immunologically, HIV-1+ATB group showed significantly lower numbers of ESAT-6-/CFP-10-specific IFN-γ+ T cells than HIV-1+LTB group. Consistently, PPD-specific IFN-γ+CD4+/CD8+ T effector cells in HIV-1+ATB group were significantly lower than those in HIV-1+LTB group (P<0.001). Hierarchy low CD8+ T-cell counts and effector function in HIV-1-infected individuals are correlated with both M.tb co-infection and active TB. Hierarchy low CD4+ T-cell counts and Th1 effector function in HIV-1+ individuals are associated with increased frequencies of active TB, but not M.tb co-infection.

Mechanisms involved in synergistic anticancer immunity of anti-4-1BB and anti-CD4 therapy.

PubMed

Choi, Beom K; Kim, Young H; Kang, Woo J; Lee, Sun K; Kim, Kwang H; Shin, Su M; Yokoyama, Wayne M; Kim, Tae Y; Kwon, Byoung S

2007-09-15

Anti-4-1BB-mediated anticancer effects were potentiated by depletion of CD4+ cells in B16F10 melanoma-bearing C57BL/6 mice. Anti-4-1BB induced the expansion and differentiation of polyclonal tumor-specific CD8+ T cells into IFN-gamma-producing CD11c+CD8+ T cells. The CD4+ cell depletion was responsible for facilitating immune cell infiltration into tumor tissues and removing some regulatory barriers such as T regulatory and indoleamine-2,3-dioxygenase (IDO)+ dendritic cells. Both monoclonal antibodies (mAb) contributed to the efficient induction of MHC class I molecules on the tumor cells in vivo. The effectors that mediated the anti-4-1BB effect were NKG2D+KLRG1+CD11c+CD8+ T cells that accumulated preferentially in the tumor tissues. Blocking NKG2D reduced the therapeutic effect by 20% to 26%, which may indicate that NKG2D contributes partially to tumor killing by the differentiated CD8+ T cells. Our results indicate that the combination of the two mAbs, agonistic anti-4-1BB and depleting anti-CD4, results in enhanced production of efficient tumor-killing CTLs, facilitation of their infiltration, and production of a susceptible tumor microenvironment.

Immunophenotyping of rheumatoid arthritis reveals a linkage between HLA-DRB1 genotype, CXCR4 expression on memory CD4(+) T cells, and disease activity.

PubMed

Nagafuchi, Yasuo; Shoda, Hirofumi; Sumitomo, Shuji; Nakachi, Shinichiro; Kato, Rika; Tsuchida, Yumi; Tsuchiya, Haruka; Sakurai, Keiichi; Hanata, Norio; Tateishi, Shoko; Kanda, Hiroko; Ishigaki, Kazuyoshi; Okada, Yukinori; Suzuki, Akari; Kochi, Yuta; Fujio, Keishi; Yamamoto, Kazuhiko

2016-07-07

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease that leads to destructive arthritis. Although the HLA class II locus is the strongest genetic risk factor for rheumatoid arthritis, the relationship between HLA class II alleles and lymphocyte activation remains unclear. We performed immunophenotyping of peripheral blood mononuclear cells on 91 HLA-DRB1-genotyped RA patients and 110 healthy donors. The frequency of memory CXCR4(+)CD4(+) T cells, and not Th1 and Th17 cells, was significantly associated with disease severity by multiple linear regression analysis. RA patients with one or more susceptible HLA-DR haplotypes (shared epitope: SE) displayed a significantly higher frequency of memory CXCR4(+)CD4(+) T cells. Moreover, the frequency of memory CXCR4(+)CD4(+) T cells significantly correlated with the expression level of HLA-DR on B cells, which was elevated in RA patients with SE. In vitro analysis and transcriptomic pathway analysis suggested that the interaction between HLA-DR and T cell receptors is an important regulator of memory CXCR4(+)CD4(+) T cells. Clinically, a higher frequency of memory CXCR4(+)CD4(+) T cells predicted a better response to CTLA4-Ig. Memory CXCR4(+)CD4(+) T cells may serve as a powerful biomarker for unraveling the linkage between HLA-DRB1 genotype and disease activity in RA.

HIV Controllers Exhibit Enhanced Frequencies of Major Histocompatibility Complex Class II Tetramer+ Gag-Specific CD4+ T Cells in Chronic Clade C HIV-1 Infection.

PubMed

Laher, Faatima; Ranasinghe, Srinika; Porichis, Filippos; Mewalal, Nikoshia; Pretorius, Karyn; Ismail, Nasreen; Buus, Søren; Stryhn, Anette; Carrington, Mary; Walker, Bruce D; Ndung'u, Thumbi; Ndhlovu, Zaza M

2017-04-01

Immune control of viral infections is heavily dependent on helper CD4 + T cell function. However, the understanding of the contribution of HIV-specific CD4 + T cell responses to immune protection against HIV-1, particularly in clade C infection, remains incomplete. Recently, major histocompatibility complex (MHC) class II tetramers have emerged as a powerful tool for interrogating antigen-specific CD4 + T cells without relying on effector functions. Here, we defined the MHC class II alleles for immunodominant Gag CD4 + T cell epitopes in clade C virus infection, constructed MHC class II tetramers, and then used these to define the magnitude, function, and relation to the viral load of HIV-specific CD4 + T cell responses in a cohort of untreated HIV clade C-infected persons. We observed significantly higher frequencies of MHC class II tetramer-positive CD4 + T cells in HIV controllers than progressors ( P = 0.0001), and these expanded Gag-specific CD4 + T cells in HIV controllers showed higher levels of expression of the cytolytic proteins granzymes A and B. Importantly, targeting of the immunodominant Gag41 peptide in the context of HLA class II DRB1*1101 was associated with HIV control ( r = -0.5, P = 0.02). These data identify an association between HIV-specific CD4 + T cell targeting of immunodominant Gag epitopes and immune control, particularly the contribution of a single class II MHC-peptide complex to the immune response against HIV-1 infection. Furthermore, these results highlight the advantage of the use of class II tetramers in evaluating HIV-specific CD4 + T cell responses in natural infections. IMPORTANCE Increasing evidence suggests that virus-specific CD4 + T cells contribute to the immune-mediated control of clade B HIV-1 infection, yet there remains a relative paucity of data regarding the role of HIV-specific CD4 + T cells in shaping adaptive immune responses in individuals infected with clade C, which is responsible for the majority of HIV infections worldwide. Understanding the contribution of HIV-specific CD4 + T cell responses in clade C infection is particularly important for developing vaccines that would be efficacious in sub-Saharan Africa, where clade C infection is dominant. Here, we employed MHC class II tetramers designed to immunodominant Gag epitopes and used them to characterize CD4 + T cell responses in HIV-1 clade C infection. Our results demonstrate an association between the frequency of HIV-specific CD4 + T cell responses targeting an immunodominant DRB1*11-Gag41 complex and HIV control, highlighting the important contribution of a single class II MHC-peptide complex to the immune response against HIV-1 infections. Copyright © 2017 American Society for Microbiology.

Pregnancy persistently affects memory T cell populations.

PubMed

Kieffer, Tom E C; Faas, Marijke M; Scherjon, Sicco A; Prins, Jelmer R

2017-02-01

Pregnancy is an immune challenge to the maternal immune system. The effects of pregnancy on maternal immunity and particularly on memory T cells during and after pregnancy are not fully known. This observational study aims to show the short term and the long term effects of pregnancy on the constitution, size and activation status of peripheral human memory T-lymphocyte populations. Effector memory (EM) and central memory (CM) T-lymphocytes were analyzed using flow cytometry of peripheral blood from 14 nulligravid, 12 primigravid and 15 parous women that were on average 18 months postpartum. The short term effects were shown by the significantly higher CD4+ EM cell and activated CD4+ memory cell proportions in primigravid women compared to nulligravid women. The persistent effects found in this study were the significantly higher proportions of CD4+ EM, CD4+ CM and activated memory T cells in parous women compared to nulligravid women. In contrast to CD4+ cells, activation status of CD8+ memory cells did not differ between the groups. This study shows that pregnancy persistently affects the pre-pregnancy CD4+ memory cell pool in human peripheral blood. During pregnancy, CD4+ T-lymphocytes might differentiate into EM cells followed by persistent higher proportions of CD4+ CM and EM cells postpartum. The persistent effects of pregnancy on memory T cells found in this study support the hypothesis that memory T cells are generated during pregnancy and that these cells could be involved in the lower complication risks in multiparous pregnancies in humans. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

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

PubMed

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

1996-08-01

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

Distinct CD4+-T-cell responses to live and heat-inactivated Aspergillus fumigatus conidia.

PubMed

Rivera, Amariliz; Van Epps, Heather L; Hohl, Tobias M; Rizzuto, Gabrielle; Pamer, Eric G

2005-11-01

Aspergillus fumigatus is an important fungal pathogen that causes invasive pulmonary disease in immunocompromised hosts. Respiratory exposure to A. fumigatus spores also causes allergic bronchopulmonary aspergillosis, a Th2 CD4+-T-cell-mediated disease that accompanies asthma. The microbial factors that influence the differentiation of A. fumigatus-specific CD4+ T lymphocytes into Th1 versus Th2 cells remain incompletely defined. We therefore examined CD4+-T-cell responses of immunologically intact mice to intratracheal challenge with live or heat-inactivated A. fumigatus spores. Live but not heat-inactivated fungal spores resulted in recruitment of gamma interferon (IFN-gamma)-producing, fungus-specific CD4+ T cells to lung airways, achieving A. fumigatus-specific frequencies exceeding 5% of total CD4+ T cells. While heat-inactivated spores did not induce detectable levels of IFN-gamma-producing, A. fumigatus-specific CD4+ T cells in the airways, they did prime CD4+ T-cell responses in draining lymph nodes that produced greater amounts of interleukin 4 (IL-4) and IL-13 than T cells responding to live conidia. While immunization with live fungal spores induced antibody responses, we found a marked decrease in isotype-switched, A. fumigatus-specific antibodies in sera of mice following immunization with heat-inactivated spores. Our studies demonstrate that robust Th1 T-cell and humoral responses are restricted to challenge with fungal spores that have the potential to germinate and cause invasive infection. How the adaptive immune system distinguishes between metabolically active and inactive fungal spores remains an important question.

Manipulating memory CD8 T cell numbers by timed enhancement of IL-2 signals1

PubMed Central

Kim, Marie T.; Kurup, Samarchith P.; Starbeck-Miller, Gabriel R.; Harty, John T.

2016-01-01

Due to the growing burden of tumors and chronic infections, manipulating CD8 T cell responses for clinical use has become an important goal for immunologists. Here, we show that dendritic cell (DC) immunization coupled with relatively early (days 1–3) or late (days 4–6) administration of enhanced IL-2-signals both increase peak effector CD8 T cell numbers, but only early IL-2 signals enhance memory numbers. IL-2 signals delivered at relatively late time points drive terminal differentiation, marked Bim mediated contraction and do not increase memory T cell numbers. In contrast, early IL-2 signals induce effector cell metabolic profiles more conducive to memory formation. Of note, down-regulation of CD80 and CD86 was observed on DCs in vivo following early IL-2 treatment. Mechanistically, early IL-2 treatment enhanced CTLA-4 expression on regulatory T (Treg) cells, and CTLA-4 blockade alongside IL-2 treatment in vivo prevented the decrease in CD80 and CD86, supporting a cell-extrinsic role of CTLA-4 in down-regulating B7-ligand expression on DCs. Finally, DC immunization followed by early IL-2 treatment and αCTLA-4 blockade resulted in lower memory CD8 T cell numbers compared to the DC + early IL-2 treatment group. These data suggest that curtailed signaling through the B7-CD28 co-stimulatory axis during CD8 T cell activation limits terminal differentiation and preserves memory CD8 T cell formation and thus, should be considered in future T cell vaccination strategies. PMID:27439516

Heat shock protein 70 (Hsp70) interacts with the Notch1 intracellular domain and contributes to the activity of Notch signaling in myelin-reactive CD4 T cells.

PubMed

Juryńczyk, Maciej; Lewkowicz, Przemysław; Domowicz, Małgorzata; Mycko, Marcin P; Selmaj, Krzysztof W

2015-10-15

Notch receptors (Notch1-4) are involved in the differentiation of CD4 T cells and the development of autoimmunity. Mechanisms regulating Notch signaling in CD4 T cells are not fully elucidated. In this study we investigated potential crosstalk between Notch pathway molecules and heat shock protein 70 (Hsp70), the major intracellular chaperone involved in the protein transport during immune responses and other stress conditions. Using Hsp70(-/-) mice we found that Hsp70 is critical for up-regulation of NICD1 and induction of Notch target genes in Jagged1- and Delta-like1-stimulated CD4 T cells. Co-immunoprecipitation analysis of wild-type CD4 T cells stimulated with either Jagged1 or Delta-like1 showed a direct interaction between NICD1 and Hsp70. Both molecules co-localized within the nucleus of CD4 T cells stimulated with Notch ligands. Molecular interaction and nuclear colocalization of NICD1 and Hsp70 were also detected in CD4 T cells reactive against myelin oligodendrocyte glycoprotein (MOG)35-55, which showed Hsp70-dependent up-regulation of both NICD1 and Notch target genes. In conclusion, we demonstrate for the first time that Hsp70 interacts with NICD1 and contributes to the activity of Notch signaling in CD4 T cells. Interaction between Hsp70 and NICD1 may represent a novel mechanism regulating Notch signaling in activated CD4 T cells. Copyright © 2015 Elsevier B.V. All rights reserved.

Evidence for a stepwise program of extrathymic T cell development within the human tonsil

PubMed Central

McClory, Susan; Hughes, Tiffany; Freud, Aharon G.; Briercheck, Edward L.; Martin, Chelsea; Trimboli, Anthony J.; Yu, Jianhua; Zhang, Xiaoli; Leone, Gustavo; Nuovo, Gerard; Caligiuri, Michael A.

2012-01-01

The development of a broad repertoire of T cells, which is essential for effective immune function, occurs in the thymus. Although some data suggest that T cell development can occur extrathymically, many researchers remain skeptical that extrathymic T cell development has an important role in generating the T cell repertoire in healthy individuals. However, it may be important in the setting of poor thymic function or congenital deficit and in the context of autoimmunity, cancer, or regenerative medicine. Here, we report evidence that a stepwise program of T cell development occurs within the human tonsil. We identified 5 tonsillar T cell developmental intermediates: (a) CD34+CD38dimLin– cells, which resemble multipotent progenitors in the bone marrow and thymus; (b) more mature CD34+CD38brightLin– cells; (c) CD34+CD1a+CD11c– cells, which resemble committed T cell lineage precursors in the thymus; (d) CD34–CD1a+CD3–CD11c– cells, which resemble CD4+CD8+ double-positive T cells in the thymus; and (e) CD34–CD1a+CD3+CD11c– cells. The phenotype of each subset closely resembled that of its thymic counterpart. The last 4 populations expressed RAG1 and PTCRA, genes required for TCR rearrangement, and all 5 subsets were capable of ex vivo T cell differentiation. TdT+ cells found within the tonsillar fibrous scaffold expressed CD34 and/or CD1a, indicating that this distinct anatomic region contributes to pre–T cell development, as does the subcapsular region of the thymus. Thus, we provide evidence of a role for the human tonsil in a comprehensive program of extrathymic T cell development. PMID:22378041

Relative Contributions of B Cells and Dendritic Cells from Lupus-Prone Mice to CD4+ T Cell Polarization.

PubMed

Choi, Seung-Chul; Xu, Zhiwei; Li, Wei; Yang, Hong; Roopenian, Derry C; Morse, Herbert C; Morel, Laurence

2018-05-01

Mouse models of lupus have shown that multiple immune cell types contribute to autoimmune disease. This study sought to investigate the involvement of B cells and dendritic cells in supporting the expansion of inflammatory and regulatory CD4 + T cells that are critical for lupus pathogenesis. We used lupus-prone B6.NZM2410.Sle1.Sle2.Sle3 (TC) and congenic C57BL/6J (B6) control mice to investigate how the genetic predisposition of these two cell types controls the activity of normal B6 T cells. Using an allogeneic in vitro assay, we showed that TC B1-a and conventional B cells expanded Th17 cells significantly more than their B6 counterparts. This expansion was dependent on CD86 and IL-6 expression and mapped to the Sle1 lupus-susceptibility locus. In vivo, TC B cells promoted greater differentiation of CD4 + T cells into Th1 and follicular helper T cells than did B6 B cells, but they limited the expansion of Foxp3 regulatory CD4 + T cells to a greater extent than did B6 B cells. Finally, when normal B6 CD4 + T cells were introduced into Rag1 -/- mice, TC myeloid/stromal cells caused their heightened activation, decreased Foxp3 regulatory CD4 + T cell differentiation, and increased renal infiltration of Th1 and Th17 cells in comparison with B6 myeloid/stromal cells. The results show that B cells from lupus mice amplify inflammatory CD4 + T cells in a nonredundant manner with myeloid/stromal cells. Copyright © 2018 by The American Association of Immunologists, Inc.

T cells establish and maintain CNS viral infection in HIV-infected humanized mice.

PubMed

Honeycutt, Jenna B; Liao, Baolin; Nixon, Christopher C; Cleary, Rachel A; Thayer, William O; Birath, Shayla L; Swanson, Michael D; Sheridan, Patricia; Zakharova, Oksana; Prince, Francesca; Kuruc, JoAnn; Gay, Cynthia L; Evans, Chris; Eron, Joseph J; Wahl, Angela; Garcia, J Victor

2018-06-04

The human brain is an important site of HIV replication and persistence during antiretroviral therapy (ART). Direct evaluation of HIV infection in the brains of otherwise healthy individuals is not feasible; therefore, we performed a large-scale study of bone marrow/liver/thymus (BLT) humanized mice as an in vivo model to study HIV infection in the brain. Human immune cells, including CD4+ T cells and macrophages, were present throughout the BLT mouse brain. HIV DNA, HIV RNA, and/or p24+ cells were observed in the brains of HIV-infected animals, regardless of the HIV isolate used. HIV infection resulted in decreased numbers of CD4+ T cells, increased numbers of CD8+ T cells, and a decreased CD4+/CD8+ T cell ratio in the brain. Using humanized T cell-only mice (ToM), we demonstrated that T cells establish and maintain HIV infection of the brain in the complete absence of human myeloid cells. HIV infection of ToM resulted in CD4+ T cell depletion and a reduced CD4+/CD8+ T cell ratio. ART significantly reduced HIV levels in the BLT mouse brain, and the immune cell populations present were indistinguishable from those of uninfected controls, which demonstrated the effectiveness of ART in controlling HIV replication in the CNS and returning cellular homeostasis to a pre-HIV state.

IL-17+ regulatory T cells in the microenvironments of chronic inflammation and cancer.

PubMed

Kryczek, Ilona; Wu, Ke; Zhao, Ende; Wei, Shuang; Vatan, Linhua; Szeliga, Wojciech; Huang, Emina; Greenson, Joel; Chang, Alfred; Roliński, Jacek; Radwan, Piotr; Fang, Jingyuan; Wang, Guobin; Zou, Weiping

2011-04-01

Foxp3(+)CD4(+) regulatory T (Treg) cells inhibit immune responses and temper inflammation. IL-17(+)CD4(+) T (Th17) cells mediate inflammation of autoimmune diseases. A small population of IL-17(+)Foxp3(+)CD4(+) T cells has been observed in peripheral blood in healthy human beings. However, the biology of IL-17(+)Foxp3(+)CD4(+) T cells remains poorly understood in humans. We investigated their phenotype, cytokine profile, generation, and pathological relevance in patients with ulcerative colitis. We observed that high levels of IL-17(+)Foxp3(+)CD4(+) T cells were selectively accumulated in the colitic microenvironment and associated colon carcinoma. The phenotype and cytokine profile of IL-17(+)Foxp3(+)CD4(+) T cells was overlapping with Th17 and Treg cells. Myeloid APCs, IL-2, and TGF-β are essential for their induction from memory CCR6(+) T cells or Treg cells. IL-17(+)Foxp3(+)CD4(+) T cells functionally suppressed T cell activation and stimulated inflammatory cytokine production in the colitic tissues. Our data indicate that IL-17(+)Foxp3(+) cells may be "inflammatory" Treg cells in the pathological microenvironments. These cells may contribute to the pathogenesis of ulcerative colitis through inducing inflammatory cytokines and inhibiting local T cell immunity, and in turn may mechanistically link human chronic inflammation to tumor development. Our data therefore challenge commonly held beliefs of the anti-inflammatory role of Treg cells and suggest a more complex Treg cell biology, at least in the context of human chronic inflammation and associated carcinoma.

Evaluation of the Immunologic Impact of RAF Inhibitors to Guide Optimal Combination of RAF Inhibitors and Immunotherapy for the Treatment of Advanced Melanoma

DTIC Science & Technology

2016-03-01

TILS (Vehicle) Fr eq o f P ar en t CD4+ T cells CD4+CD25+Foxp3+ CD8+ CD8+PD1+ CD8+GrzB...PDL1+ CD 4+ T ce lls CD 4+ CD 25 +F ox p3 + CD 8+ CD 8+ PD 1+ CD 8+ Gr zB + CD 8+ Ki6 7+ 0 10 20 30 40 Day 5 - TILS (BRAFi) Fr eq o f P ar en t...ce lls CD 4+ CD 25 +F ox p3 + CD 8+ CD 8+ PD 1+ CD 8+ Gr zB + CD 8+ Ki6 7+ 0 10 20 30 40 Day 2 - TILS (Vehicle) Fr eq o f P ar en t CD4+ T cells

Dissection of a circulating CD3+ CD20+ T cell subpopulation in patients with psoriasis.

PubMed

Niu, J; Zhai, Z; Hao, F; Zhang, Y; Song, Z; Zhong, H

2018-05-01

CD3 + CD20 + T cells are a population of CD3 + T cells that express CD20 and identified in healthy donors and autoimmune diseases. However, the nature and role of these cells in patients with psoriasis remain unclear. In this study, we aimed to investigate the level, phenotype, functional and clinical relevance of CD3 + CD20 + T cells in the peripheral blood of patients with psoriasis. We found that a small subset of CD3 + T cells expressed CD20 molecule in the peripheral blood of patients with psoriasis, and their levels were similar to those in healthy donors. Circulating CD3 + CD20 + T cells in patients with psoriasis were enriched in CD4 + cells and displayed an activated effector phenotype, as these cells contained fewer CD45RA + -naive and CCR7 + cells with increased activity than those of CD3 + T cells lacking CD20. In addition, compared with healthy donors, circulating CD3 + CD20 + T cells in patients with psoriasis produced more cytokines, interleukin (IL)-17A, tumour necrosis factor (TNF)-α and IL-21, but not IL-4 and IFN-γ. Furthermore, a significantly positive correlation was found between the levels of IL-17A, TNF-α and IL-21-production CD3 + CD20 + T cells with Psoriasis Area and Severity Index scores. Our findings suggest that CD3 + CD20 + T cells may play a role in the pathogenesis of psoriasis. © 2018 British Society for Immunology.

Mycobacterium tuberculosis Specific CD8+ T Cells Rapidly Decline with Antituberculosis Treatment

PubMed Central

Nyendak, Melissa R.; Park, Byung; Null, Megan D.; Baseke, Joy; Swarbrick, Gwendolyn; Mayanja-Kizza, Harriet; Nsereko, Mary; Johnson, Denise F.; Gitta, Phineas; Okwera, Alphonse; Goldberg, Stefan; Bozeman, Lorna; Johnson, John L.; Boom, W. Henry; Lewinsohn, Deborah A.; Lewinsohn, David M.

2013-01-01

Rationale Biomarkers associated with response to therapy in tuberculosis could have broad clinical utility. We postulated that the frequency of Mycobacterium tuberculosis (Mtb) specific CD8+ T cells, by virtue of detecting intracellular infection, could be a surrogate marker of response to therapy and would decrease during effective antituberculosis treatment. Objectives: We sought to determine the relationship of Mtb specific CD4+ T cells and CD8+ T cells with duration of antituberculosis treatment. Materials and Methods We performed a prospective cohort study, enrolling between June 2008 and August 2010, of HIV-uninfected Ugandan adults (n = 50) with acid-fast bacillus smear-positive, culture confirmed pulmonary TB at the onset of antituberculosis treatment and the Mtb specific CD4+ and CD8+ T cell responses to ESAT-6 and CFP-10 were measured by IFN-γ ELISPOT at enrollment, week 8 and 24. Results There was a significant difference in the Mtb specific CD8+ T response, but not the CD4+ T cell response, over 24 weeks of antituberculosis treatment (p<0.0001), with an early difference observed at 8 weeks of therapy (p = 0.023). At 24 weeks, the estimated Mtb specific CD8+ T cell response decreased by 58%. In contrast, there was no significant difference in the Mtb specific CD4+ T cell during the treatment. The Mtb specific CD4+ T cell response, but not the CD8+ response, was negatively impacted by the body mass index. Conclusions Our data provide evidence that the Mtb specific CD8+ T cell response declines with antituberculosis treatment and could be a surrogate marker of response to therapy. Additional research is needed to determine if the Mtb specific CD8+ T cell response can detect early treatment failure, relapse, or to predict disease progression. PMID:24324704

Tonic LAT-HDAC7 Signals Sustain Nur77 and Irf4 Expression to Tune Naive CD4 T Cells.

PubMed

Myers, Darienne R; Lau, Tannia; Markegard, Evan; Lim, Hyung W; Kasler, Herbert; Zhu, Minghua; Barczak, Andrea; Huizar, John P; Zikherman, Julie; Erle, David J; Zhang, Weiguo; Verdin, Eric; Roose, Jeroen P

2017-05-23

CD4 + T cells differentiate into T helper cell subsets in feedforward manners with synergistic signals from the T cell receptor (TCR), cytokines, and lineage-specific transcription factors. Naive CD4 + T cells avoid spontaneous engagement of feedforward mechanisms but retain a prepared state. T cells lacking the adaptor molecule LAT demonstrate impaired TCR-induced signals yet cause a spontaneous lymphoproliferative T helper 2 (T H 2) cell syndrome in mice. Thus, LAT constitutes an unexplained maintenance cue. Here, we demonstrate that tonic signals through LAT constitutively export the repressor HDAC7 from the nucleus of CD4 + T cells. Without such tonic signals, HDAC7 target genes Nur77 and Irf4 are repressed. We reveal that Nur77 suppresses CD4 + T cell proliferation and uncover a suppressive role for Irf4 in T H 2 polarization; halving Irf4 gene-dosage leads to increases in GATA3 + and IL-4 + cells. Our studies reveal that naive CD4 + T cells are dynamically tuned by tonic LAT-HDAC7 signals. Published by Elsevier Inc.

CXCL4 is a novel inducer of human Th17 cells and correlates with IL‐17 and IL‐22 in psoriatic arthritis

PubMed Central

Affandi, Alsya J.; Silva‐Cardoso, Sandra C.; Garcia, Samuel; Leijten, Emmerik F. A.; van Kempen, Tessa S.; Marut, Wioleta; van Roon, Joel A. G.

2018-01-01

Abstract CXCL4 regulates multiple facets of the immune response and is highly upregulated in various Th17‐associated rheumatic diseases. However, whether CXCL4 plays a direct role in the induction of IL‐17 production by human CD4+ T cells is currently unclear. Here, we demonstrated that CXCL4 induced human CD4+ T cells to secrete IL‐17 that co‐expressed IFN‐γ and IL‐22, and differentiated naïve CD4+ T cells to become Th17‐cytokine producing cells. In a co‐culture system of human CD4+ T cells with monocytes or myeloid dendritic cells, CXCL4 induced IL‐17 production upon triggering by superantigen. Moreover, when monocyte‐derived dendritic cells were differentiated in the presence of CXCL4, they orchestrated increased levels of IL‐17, IFN‐γ, and proliferation by CD4+ T cells. Furthermore, the CXCL4 levels in synovial fluid from psoriatic arthritis patients strongly correlated with IL‐17 and IL‐22 levels. A similar response to CXCL4 of enhanced IL‐17 production by CD4+ T cells was also observed in patients with psoriatic arthritis. Altogether, we demonstrate that CXCL4 boosts pro‐inflammatory cytokine production especially IL‐17 by human CD4+ T cells, either by acting directly or indirectly via myeloid antigen presenting cells, implicating a role for CXCL4 in PsA pathology. PMID:29193036

Cytomegalovirus Infection Leads to Development of High Frequencies of Cytotoxic Virus-Specific CD4+ T Cells Targeted to Vascular Endothelium

PubMed Central

Begum, Jusnara; Lal, Neeraj; Zuo, Jianmin; Beggs, Andrew; Moss, Paul

2016-01-01

Cytomegalovirus (CMV) infection elicits a very strong and sustained intravascular T cell immune response which may contribute towards development of accelerated immune senescence and vascular disease in older people. Virus-specific CD8+ T cell responses have been investigated extensively through the use of HLA-peptide tetramers but much less is known regarding CMV-specific CD4+ T cells. We used a range of HLA class II-peptide tetramers to investigate the phenotypic and transcriptional profile of CMV-specific CD4+ T cells within healthy donors. We show that such cells comprise an average of 0.45% of the CD4+ T cell pool and can reach up to 24% in some individuals (range 0.01–24%). CMV-specific CD4+ T cells display a highly differentiated effector memory phenotype and express a range of cytokines, dominated by dual TNF-α and IFN-γ expression, although substantial populations which express IL-4 were seen in some donors. Microarray analysis and phenotypic expression revealed a profile of unique features. These include the expression of CX3CR1, which would direct cells towards fractalkine on activated endothelium, and the β2-adrenergic receptor, which could permit rapid response to stress. CMV-specific CD4+ T cells display an intense cytotoxic profile with high level expression of granzyme B and perforin, a pattern which increases further during aging. In addition CMV-specific CD4+ T cells demonstrate strong cytotoxic activity against antigen-loaded target cells when isolated directly ex vivo. PD-1 expression is present on 47% of cells but both the intensity and distribution of the inhibitory receptor is reduced in older people. These findings reveal the marked accumulation and unique phenotype of CMV-specific CD4+ T cells and indicate how such T cells may contribute to the vascular complications associated with CMV in older people. PMID:27606804

Osthole promotes anti-tumor immune responses in tumor-bearing mice with hepatocellular carcinoma.

PubMed

Zhang, Lurong; Jiang, Guorong; Yao, Fei; Liang, Guoqiang; Wang, Fei; Xu, Heng; Wu, Yan; Yu, Xiao; Liu, Haiyan

2015-06-01

Osthole, a natural coumarin derivative, has been shown to have anti-tumor and anti-inflammatory activity. However, the effect of osthole on anti-tumor immune responses in tumor-bearing mice has not yet been reported. In the present study, osthole treatment did not affect the weight and the coefficient of thymus and spleen in tumor-bearing mice with hepatocellular carcinoma (HCC). However, osthole administration significantly elevated the proportion and number of the splenic CD8(+) T cells, the proportion of CD4(+) T and CD8(+) T cells in tumor tissues, and the levels of IL-2 and TNF-α in the serum of HCC tumor-bearing mice. Our results suggested that osthole could promote the activation of the tumor-infiltrating CD4(+) T and CD8(+) T cells, and elevate the proportion of CD4(+) and CD8(+) effector T cells. Osthole treatment also significantly decreased the proportion of CD4(+)CD25(+)Foxp3(+) regulatory T cells in the spleen. Taken together, osthole could enhance the T cell mediated anti-tumor immune responses in the tumor-bearing mice with HCC.

Diverse Epitope Specificity, Immunodominance Hierarchy, and Functional Avidity of Effector CD4 T Cells Established During Priming Is Maintained in Lung After Influenza A Virus Infection.

PubMed

Richards, Katherine A; DiPiazza, Anthony T; Rattan, Ajitanuj; Knowlden, Zackery A G; Yang, Hongmei; Sant, Andrea J

2018-01-01

One of the major contributions to protective immunity to influenza viruses that is provided by virus-specific CD4 T cells is delivery of effector function to the infected lung. However, there is little known about the selection and breadth of viral epitope-specific CD4 T cells that home to the lung after their initial priming. In this study, using a mouse model of influenza A infection and an unbiased method of epitope identification, the viral epitope-specific CD4 T cells elicited after infection were identified and quantified. We found that a very diverse specificity of CD4 T cells is primed by infection, including epitopes from hemagglutinin, neuraminidase, matrix protein, nucleoprotein, and non-structural protein-1. Using peptide-specific cytokine EliSpots, the diversity and immunodominance hierarchies established in the lung-draining lymph node were compared with specificities of CD4 T cells that home to the lung. Our studies revealed that CD4 T cells of all epitope specificities identified in peripheral lymphoid tissue home back to the lung and that most of these lung-homing cells are localized within the tissue rather than the pulmonary vasculature. There is a striking shift of CD4 T cell functionality that enriches for IFN-γ production as cells are primed in the lymph node, enter the lung vasculature, and finally establish residency in the tissue, but with no apparent shifts in their functional avidity. We conclude that CD4 T cells of broad viral epitope specificity are recruited into the lung after influenza infection, where they then have the opportunity to encounter infected or antigen-bearing antigen-presenting cells.

The Distinctive Sensitivity to Microgravity of Immune Cell Subpopulations

NASA Astrophysics Data System (ADS)

Chen, Hui; Luo, Haiying; Liu, Jing; Wang, Peng; Dong, Dandan; Shang, Peng; Zhao, Yong

2015-11-01

Immune dysfunction in astronauts is well documented after spaceflights. Microgravity is one of the key factors directly suppressing the function of immune system. However, it is unclear which subpopulations of immune cells including innate and adaptive immune cells are more sensitive to microgravity We herein investigated the direct effects of modeled microgravity (MMg) on different immune cells in vitro. Mouse splenocytes, thymocytes and bone marrow cells were exposed to MMg for 16 hrs. The survival and the phenotypes of different subsets of immune cells including CD4+T cells, CD8+T cells, CD4+Foxp3+ regulatory T cells (Treg), B cells, monocytes/macrophages, dendritic cells (DCs), natural killer cells (NK) were determined by flow cytometry. After splenocytes were cultured under MMg for 16h, the cell frequency and total numbers of monocytes, macrophages and CD4+Foxp3+T cells were significantly decreased more than 70 %. MMg significantly decreased the cell numbers of CD8+ T cells, B cells and neutrophils in splenocytes. The cell numbers of CD4+T cells and NK cells were unchanged significantly when splenocytes were cultured under MMg compared with controls. However, MMg significantly increased the ratio of mature neutrophils to immature neutrophils in bone marrow and the cell number of DCs in splenocytes. Based on the cell survival ability, monocytes, macrophages and CD4+Foxp3+Treg cells are most sensitive to microgravity; CD4+T cells and NK cells are resistant to microgravity; CD8+T cells and neutrophils are impacted by short term microgravity exposure. Microgravity promoted the maturation of neutrophils and development of DCs in vitro. The present studies offered new insights on the direct effects of MMg on the survival and homeostasis of immune cell subsets.

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

PubMed

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

2018-05-09

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

Dendritic cells rapidly undergo apoptosis in vitro following culture with activated CD4+ Vα24 natural killer T cells expressing CD40L

PubMed Central

Nieda, M; Kikuchi, A; Nicol, A; Koezuka, Y; Ando, Y; Ishihara, S; Lapteva, N; Yabe, T; Tokunaga, K; Tadokoro, K; Juji, T

2001-01-01

Human Vα24 natural killer T (Vα24NKT) cells are activated by α-glycosylceramide-pulsed dendritic cells (DCs) in a CD1d-dependent and T-cell receptor-mediated manner. There are two major subpopulations of Vα24NKT cells, CD4– CD8– Vα24NKT and CD4+ Vα24NKT cells. We have recently shown that activated CD4– CD8– Vα24NKT cells have cytotoxic activity against DCs, but knowledge of the molecules responsible for cytotoxicity of Vα24NKT cells is currently limited. We aimed to investigate whether CD4+ Vα24NKT cells also have cytotoxic activity against DCs and to determine the mechanisms underlying any observed cytotoxic activity. We demonstrated that activated CD4+ Vα24NKT cells [CD40 ligand (CD40L) -positive] have cytotoxic activity against DCs (strongly CD40-positive), but not against monocytes (weakly CD40-positive) or phytohaemagglutinin blast T cells (CD40-negative), and that apoptosis of DCs significantly contributes to the observed cytotoxicity. The apoptosis of DCs following culture with activated CD4+ Vα24NKT cells, but not with resting CD4+ Vα24NKT cells (CD40L-negative), was partially inhibited by anti-CD40L mAb. Direct ligation of CD40 on the DCs by the anti-CD40 antibody also induced apoptosis of DCs. Our results suggest that CD40–CD40L interaction plays an important role in the induction of apoptosis of DCs following culture with activated CD4+ Vα24NKT cells. The apoptosis of DCs from normal donors, triggered by the CD40–CD40L interaction, may contribute to the homeostatic regulation of the normal human immune system, preventing the interminable activation of activated CD4+ Vα24NKT cells by virtue of apoptosis of DCs. PMID:11260318

Atorvastatin reduces T-cell activation and exhaustion among HIV-infected cART-treated suboptimal immune responders in Uganda: a randomised crossover placebo-controlled trial.

PubMed

Nakanjako, Damalie; Ssinabulya, Isaac; Nabatanzi, Rose; Bayigga, Lois; Kiragga, Agnes; Joloba, Moses; Kaleebu, Pontiano; Kambugu, Andrew D; Kamya, Moses R; Sekaly, Rafick; Elliott, Alison; Mayanja-Kizza, Harriet

2015-03-01

T-cell activation independently predicts mortality, poor immune recovery and non-AIDS illnesses during combination antiretroviral therapy (cART). Atorvastatin showed anti-immune activation effects among HIV-infected cART-naïve individuals. We investigated whether adjunct atorvastatin therapy reduces T-cell activation among cART-treated adults with suboptimal immune recovery. A randomised double-blind placebo-controlled crossover trial, of atorvastatin 80 mg daily vs. placebo for 12 weeks, was conducted among individuals with CD4 increase <295 cells/μl after seven years of suppressive cART. Change in T-cell activation (CD3 + CD4 + /CD8 + CD38 + HLADR+) and in T-cell exhaustion (CD3 + CD4 + /CD8 + PD1 + ) was measured using flow cytometry. Thirty patients were randomised, 15 to each arm. Atorvastatin resulted in a 28% greater reduction in CD4 T-cell activation (60% reduction) than placebo (32% reduction); P = 0.001. Atorvastatin also resulted in a 35% greater reduction in CD8-T-cell activation than placebo (49% vs. 14%, P = 0.0009), CD4 T-cell exhaustion (27% vs. 17% in placebo), P = 0.001 and CD8 T-cell exhaustion (27% vs. 16%), P = 0.004. There was no carry-over/period effect. Expected adverse events were comparable in both groups, and no serious adverse events were reported. Atorvastatin reduced T-cell immune activation and exhaustion among cART-treated adults in a Ugandan cohort. Atorvastatin adjunct therapy should be explored as a strategy to improve HIV treatment outcomes among people living with HIV in sub-Saharan Africa. © 2014 John Wiley & Sons Ltd.

HIV-1 DNA burden dynamics in CD4 T cells and monocytes in patients undergoing a transient therapy interruption.

PubMed

Garbuglia, Anna Rosa; Calcaterra, Silvia; D'Offizi, Gianpiero; Topino, Simone; Narciso, Pasquale; Lillo, Flavia; Girardi, Enrico; Capobianchi, Maria Rosaria

2004-11-01

Replication-competent HIV, as well as HIV-1 DNA, has been detected in CD4 T cells and in monocytes during antiretroviral therapy (ART), indicating that these cells could represent an important viral reservoir. We measured HIV-1 DNA in monocytes and CD4 T cells in patients undergoing transient therapy interruption (TTI), to establish the dynamic of HIV-1 DNA burden and to find possible correlations with immune restoration and re-establishment of virological control after ART resumption. In most patients CD4 depletion and viral load rebound followed TTI. Rapid resumption of virological and immunological control was achieved after ART reintroduction. After TTI, in most cases a transient increase of both monocyte and CD4 HIV-1 DNA burden was observed. After ART reintroduction, both CD4 T cell and monocyte HIV-1 DNA copy number decreased, reaching baseline levels at the end of observation. At this time monocyte HIV-1 DNA burden was always undetectable, while CD4 T cell HIV-1 DNA burden was lower than at baseline. As CD4 T cell HIV-1 DNA values are independently associated with CD4 depletion, the increase of HIV-1 DNA burden in these cells after TTI is presumably due to acute infection, causing cell death. This is also supported by the pattern of 2-LTR appearance in these cells after TTI. HIV-1 DNA burden in monocytes and CD4 T cells show high correlation, suggesting reciprocal re-feeding of two cell populations. Repopulation by HIV these cells after TTI is temporary, and no significant changes of HIV-1 DNA burden were observed after ART resumption respect to pre-TTI period.

DJ-1/Park7 Sensitive Na+ /H+ Exchanger 1 (NHE1) in CD4+ T Cells.

PubMed

Zhou, Yuetao; Shi, Xiaolong; Chen, Hong; Zhang, Shaqiu; Salker, Madhuri S; Mack, Andreas F; Föller, Michael; Mak, Tak W; Singh, Yogesh; Lang, Florian

2017-11-01

DJ-1/Park7 is a redox-sensitive chaperone protein counteracting oxidation and presumably contributing to the control of oxidative stress responses and thus inflammation. DJ-1 gene deletion exacerbates the progression of Parkinson's disease presumably by augmenting oxidative stress. Formation of reactive oxygen species (ROS) is paralleled by activation of the Na + /H + exchanger 1 (NHE1). ROS formation in CD4 + T cells plays a decisive role in regulating inflammatory responses. In the present study, we explored whether DJ-1 is expressed in CD4 + T cells, and affects ROS production as well as NHE1 in those cells. To this end, DJ-1 and NHE1 transcript, and protein levels were quantified by qRT-PCR and Western blotting, respectively, intracellular pH (pH i ) utilizing bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein (BCECF) fluorescence, NHE activity from realkalinization after an ammonium pulse, and ROS production utilizing 2',7' -dichlorofluorescin diacetate (DCFDA) fluorescence. As a result DJ-1 was expressed in CD4 + T cells. ROS formation, NHE1 transcript levels, NHE1 protein, and NHE activity were higher in CD4 + T cells from DJ-1 deficient mice than in CD4 + T cells from wild type mice. Antioxidant N-acetyl-cysteine (NAC) and protein tyrosine kinase (PTK) inhibitor staurosporine decreased the NHE activity in DJ-1 deficient CD4 + T cells, and blunted the difference between DJ-1 -/- and DJ-1 +/+ CD4 + T cells, an observation pointing to a role of ROS in the up-regulation of NHE1 in DJ-1 -/- CD4 + T cells. In conclusion, DJ-1 is a powerful regulator of ROS production as well as NHE1 expression and activity in CD4 + T cells. J. Cell. Physiol. 232: 3050-3059, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

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

PubMed

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

2017-09-15

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

HIV-DNA content in different CD4+ T-cell subsets correlates with CD4+ cell :  CD8+ cell ratio or length of efficient treatment.

PubMed

Gibellini, Lara; Pecorini, Simone; De Biasi, Sara; Bianchini, Elena; Digaetano, Margherita; Pinti, Marcello; Carnevale, Gianluca; Borghi, Vanni; Guaraldi, Giovanni; Mussini, Cristina; Cossarizza, Andrea; Nasi, Milena

2017-06-19

HIV establishes a latent infection at different degrees within naïve (TN) or central (TCM) and effector memory (TEM) CD4 T cell. Studying patients in whom HIV production was suppressed by combined antiretroviral therapy, our main aim was to find which factors are related or can influence intracellular viral reservoir in different CD4 T-cell subsets. We enrolled 32 HIV patients successfully treated for more than 2 years, with a CD4 T-cell count more than 500 cells/μl and plasma viremia undetectable from at least 1 year. Proviral HIV-DNA, the amount of cells expressing signal-joint T-cell receptor rearrangement excision circles and telomere length were quantified by droplet digital PCR in highly purified, sorted CD4 T-cell subsets; plasma IL-7 and IL-15 were measured by ELISA. HIV-DNA was significantly lower in TN cells compared with TCM or to TEM. Conversely, TN cells contained more signal-joint T-cell receptor rearrangement excision circles compared with TCM or to TEM; no appreciable changes were observed in telomere length. HIV-DNA content was significantly higher in TN and TCM cells, but not in TEM, from patients with shorter time of treatment, or in those with lower CD4 : CD8 ratio. Length of treatment or recovery of CD4 : CD8 ratio significantly influences viral reservoir in both TN and TCM. Measuring HIV-DNA in purified lymphocyte populations allows a better monitoring of HIV reservoir and could be useful for designing future eradication strategies.

Nanostructure and force spectroscopy analysis of human peripheral blood CD4+ T cells using atomic force microscopy.

PubMed

Hu, Mingqian; Wang, Jiongkun; Cai, Jiye; Wu, Yangzhe; Wang, Xiaoping

2008-09-12

To date, nanoscale imaging of the morphological changes and adhesion force of CD4(+) T cells during in vitro activation remains largely unreported. In this study, we used atomic force microscopy (AFM) to study the morphological changes and specific binding forces in resting and activated human peripheral blood CD4(+) T cells. The AFM images revealed that the volume of activated CD4(+) T cells increased and the ultrastructure of these cells also became complex. Using a functionalized AFM tip, the strength of the specific binding force of the CD4 antigen-antibody interaction was found to be approximately three times that of the unspecific force. The adhesion forces were not randomly distributed over the surface of a single activated CD4(+) T cell, indicated that the CD4 molecules concentrated into nanodomains. The magnitude of the adhesion force of the CD4 antigen-antibody interaction did not change markedly with the activation time. Multiple bonds involved in the CD4 antigen-antibody interaction were measured at different activation times. These results suggest that the adhesion force involved in the CD4 antigen-antibody interaction is highly selective and of high affinity.

Limited immune surveillance in lymphoid tissue by cytolytic CD4+ T cells during health and HIV disease

PubMed Central

McLane, Laura M.; Steblyanko, Maria; Anikeeva, Nadia; Ablanedo-Terrazas, Yuria; Demers, Korey; Eller, Michael A.; Streeck, Hendrik; Jansson, Marianne; Sönnerborg, Anders; Canaday, David H.; Naji, Ali; Wherry, E. John; Robb, Merlin L.; Reyes-Teran, Gustavo; Sykulev, Yuri; Betts, Michael R.

2018-01-01

CD4+ T cells subsets have a wide range of important helper and regulatory functions in the immune system. Several studies have specifically suggested that circulating effector CD4+ T cells may play a direct role in control of HIV replication through cytolytic activity or autocrine β-chemokine production. However, it remains unclear whether effector CD4+ T cells expressing cytolytic molecules and β-chemokines are present within lymph nodes (LNs), a major site of HIV replication. Here, we report that expression of β-chemokines and cytolytic molecules are enriched within a CD4+ T cell population with high levels of the T-box transcription factors T-bet and eomesodermin (Eomes). This effector population is predominately found in peripheral blood and is limited in LNs regardless of HIV infection or treatment status. As a result, CD4+ T cells generally lack effector functions in LNs, including cytolytic capacity and IFNγ and β-chemokine expression, even in HIV elite controllers and during acute/early HIV infection. While we do find the presence of degranulating CD4+ T cells in LNs, these cells do not bear functional or transcriptional effector T cell properties and are inherently poor to form stable immunological synapses compared to their peripheral blood counterparts. We demonstrate that CD4+ T cell cytolytic function, phenotype, and programming in the peripheral blood is dissociated from those characteristics found in lymphoid tissues. Together, these data challenge our current models based on blood and suggest spatially and temporally dissociated mechanisms of viral control in lymphoid tissues. PMID:29652923