scholarly journals Direct Expansion of Functional CD25+ CD4+ Regulatory T Cells by Antigen-processing Dendritic Cells

2003 ◽  
Vol 198 (2) ◽  
pp. 235-247 ◽  
Author(s):  
Sayuri Yamazaki ◽  
Tomonori Iyoda ◽  
Kristin Tarbell ◽  
Kara Olson ◽  
Klara Velinzon ◽  
...  

An important pathway for immune tolerance is provided by thymic-derived CD25+ CD4+ T cells that suppress other CD25− autoimmune disease–inducing T cells. The antigen-presenting cell (APC) requirements for the control of CD25+ CD4+ suppressor T cells remain to be identified, hampering their study in experimental and clinical situations. CD25+ CD4+ T cells are classically anergic, unable to proliferate in response to mitogenic antibodies to the T cell receptor complex. We now find that CD25+ CD4+ T cells can proliferate in the absence of added cytokines in culture and in vivo when stimulated by antigen-loaded dendritic cells (DCs), especially mature DCs. With high doses of DCs in culture, CD25+ CD4+ and CD25− CD4+ populations initially proliferate to a comparable extent. With current methods, one third of the antigen-reactive T cell receptor transgenic T cells enter into cycle for an average of three divisions in 3 d. The expansion of CD25+ CD4+ T cells stops by day 5, in the absence or presence of exogenous interleukin (IL)-2, whereas CD25− CD4+ T cells continue to grow. CD25+ CD4+ T cell growth requires DC–T cell contact and is partially dependent upon the production of small amounts of IL-2 by the T cells and B7 costimulation by the DCs. After antigen-specific expansion, the CD25+ CD4+ T cells retain their known surface features and actively suppress CD25− CD4+ T cell proliferation to splenic APCs. DCs also can expand CD25+ CD4+ T cells in the absence of specific antigen but in the presence of exogenous IL-2. In vivo, both steady state and mature antigen-processing DCs induce proliferation of adoptively transferred CD25+ CD4+ T cells. The capacity to expand CD25+ CD4+ T cells provides DCs with an additional mechanism to regulate autoimmunity and other immune responses.

Blood ◽  
2008 ◽  
Vol 111 (4) ◽  
pp. 2053-2061 ◽  
Author(s):  
Laura Crompton ◽  
Naeem Khan ◽  
Rajiv Khanna ◽  
Laxman Nayak ◽  
Paul A. H. Moss

Antigen-specific CD8+ cytotoxic T cells often demonstrate extreme conservation of T-cell receptor (TCR) usage between different individuals, but similar characteristics have not been documented for CD4+ T cells. CD4+ T cells predominantly have a helper immune role, but a cytotoxic CD4+ T-cell subset has been characterized, and we have studied the cytotoxic CD4+ T-cell response to a peptide from human cytomegalovirus glycoprotein B presented through HLA-DRB*0701. We show that this peptide elicits a cytotoxic CD4+ T-cell response that averages 3.6% of the total CD4+ T-cell repertoire of cytomegalovirus-seropositive donors. Moreover, CD4+ cytotoxic T-cell clones isolated from different individuals exhibit extensive conservation of TCR usage, which indicates strong T-cell clonal selection for peptide recognition. Remarkably, this TCR sequence was recently reported in more than 50% of cases of CD4+ T-cell large granular lymphocytosis. Immunodominance of cytotoxic CD4+ T cells thus parallels that of CD8+ subsets and suggests that cytotoxic effector function is critical to the development of T-cell clonal selection, possibly from immune competition secondary to lysis of antigen-presenting cells. In addition, these TCR sequences are highly homologous to those observed in HLA-DR7+ patients with CD4+ T-cell large granular lymphocytosis and implicate cytomegalovirus as a likely antigenic stimulus for this disorder.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3110-3110
Author(s):  
Erwan R. Piriou ◽  
Christine Jansen ◽  
Karel van Dort ◽  
Iris De Cuyper ◽  
Nening M. Nanlohy ◽  
...  

Abstract Objective: EBV-specific CD8+ T cells have been extensively studied in various settings, and appear to play a major role in the control of EBV-related malignancies. In contrast, it is still unclear whether EBV-specific CD4+ T cells play a role in vivo. To study this question, an assay was developed to measure the CD4+ T-cell response towards two EBV antigens, in both healthy (n=14) and HIV-infected subjects (n=23). In addition, both HAART-treated (n=12) and untreated HIV+ individuals (n=14) - including progressors to EBV-related lymphoma - were studied longitudinally. Methods: EBV-specific CD4+ T cells were stimulated with peptide pools from latent protein EBNA1 and lytic protein BZLF1, and detected by measurement of IFNg-production. Results: After direct ex vivo stimulation, EBNA1 or BZLF1-specific IFNg- (and/or IL2) producing CD4+ T cell numbers were low, and measurable in less than half of the subjects studied (either HIV- and HIV+). Therefore, PBMC were cultured for 12 days in the presence of peptides and IL2 (from day 3), and then restimulated with peptides, allowing specific and reproducible expansion of EBV-specific CD4+ T cells, independent of HLA type and ex vivo antigen processing. Interestingly, numbers of EBV-specific CD4+ T cells inversely correlated with EBV viral load, implying an important role for EBV-specific CD4+ T cells in the control of EBV in vivo. Untreated HIV-infected individuals had a lower CD4+ T cell response to EBNA1 and BZLF1 as compared to healthy EBV carriers and HAART-treated HIV+ subjects. In longitudinal samples, EBNA1-specific, but not BZLF1-specific T-cell numbers increased after HAART, while EBV load was not affected by treatment. In all the progressors to EBV-related lymphoma, EBV-specific CD4+ T cells were lost at least 24 months before lymphoma diagnosis. Conclusions: Both cross-sectional and longitudinal data suggest an important role for EBV-specific CD4+ T cells in the control of EBV-related malignancies. Furthermore, it seems that HAART treatment leads to recovery of EBNA1-specific, but not BZLF1-specific CD4+ T-cell responses, implying changes in the latency pattern of EBV, despite an unaltered cell-associated EBV DNA load. Thus, early HAART treatment might prevent loss of specific CD4+ T-cell help and progression to NHL.


2014 ◽  
Vol 211 (3) ◽  
pp. 529-543 ◽  
Author(s):  
Julio Gomez-Rodriguez ◽  
Elizabeth A. Wohlfert ◽  
Robin Handon ◽  
Françoise Meylan ◽  
Julie Z. Wu ◽  
...  

A proper balance between Th17 and T regulatory cells (Treg cells) is critical for generating protective immune responses while minimizing autoimmunity. We show that the Tec family kinase Itk (IL2-inducible T cell kinase), a component of T cell receptor (TCR) signaling pathways, influences this balance by regulating cross talk between TCR and cytokine signaling. Under both Th17 and Treg cell differentiation conditions, Itk−/− CD4+ T cells develop higher percentages of functional FoxP3+ cells, associated with increased sensitivity to IL-2. Itk−/− CD4+ T cells also preferentially develop into Treg cells in vivo. We find that Itk-deficient T cells exhibit reduced TCR-induced phosphorylation of mammalian target of rapamycin (mTOR) targets, accompanied by downstream metabolic alterations. Surprisingly, Itk−/− cells also exhibit reduced IL-2–induced mTOR activation, despite increased STAT5 phosphorylation. We demonstrate that in wild-type CD4+ T cells, TCR stimulation leads to a dose-dependent repression of Pten. However, at low TCR stimulation or in the absence of Itk, Pten is not effectively repressed, thereby uncoupling STAT5 phosphorylation and phosphoinositide-3-kinase (PI3K) pathways. Moreover, Itk-deficient CD4+ T cells show impaired TCR-mediated induction of Myc and miR-19b, known repressors of Pten. Our results demonstrate that Itk helps orchestrate positive feedback loops integrating multiple T cell signaling pathways, suggesting Itk as a potential target for altering the balance between Th17 and Treg cells.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 1417-1417
Author(s):  
Patrick Adair ◽  
Yong Chan Kim ◽  
Kathleen P. Pratt ◽  
David W Scott

Abstract Engineered T cells are a vital component in the armamentarium of cellular therapies. In this presentation, we examine how human CD4+ T cells, genetically engineered to express a T-cell receptor (TCR) specific for a C2 domain epitope of the coagulation protein cofactor FVIII, can be skewed or polarized to different T-helper subsets. Two TCRs were cloned from Th2 and Th17/Th1 phenotyped CD4+ T cells isolated via a tetramer guided epitope mapping (TGEM) technique from a hemophilia A subject after clinical diagnosis of an inhibitor (neutralizing antibody) to FVIII given as replacement therapy. The two TCRs were cloned using a 5’ RACE with semi-nested PCR and transduced via a retroviral vector into healthy non-hemophilia A human donor CD4+ T cells. Based on proliferation and HLA class II tetramer staining data, engineered CD4+ T cells expressing the different cloned TCRs exhibited different avidities for the same C2 peptide (containing the epitope) over a dose titration curve, despite similar levels of TCR expression on the CD4 T-cell surface. IFN-γ, TNF-α, IL-6, and IL-10 cytokine production levels following stimulation with C2 peptide and DR1 antigen presenting cells, as measured by cytokine bead analysis, were significantly greater for the higher avidity TCR, which was cloned from a “Th2” phenotyped CD4+ T-cell clone. Interestingly, neither the engineered CD4+ T cells expressing the Th2 TCR nor the cells expressing the Th17/Th1 TCR produced cytokines characteristic of their respective original parental clones. Rather, they reflected the cytokine profiles of the donor populations used for transduction. These preliminary data led us to investigate how the different avidities of the two cloned TCRs can modulate the T-helper subset skewing/differentiation potential of engineered CD4+T cells. We hypothesized that the TCR is merely a switch that can activate or direct engineered CD4+ T cells to an antigen-specific response that would be skewed to the T-helper phenotypes of the cells prior to TCR transduction. We further hypothesized that this response could be modulated after TCR transduction according to the apparent tetramer avidity of the engineered cells. We successfully skewed the engineered human T-helper cells to Th1, Th2 and Th17 lineages, based on T-helper signature cytokine expression and the transcription factors T-bet, Gata3 and RORγt. Moreover, we observed that TCR transduction into naïve human CD4+ T cells did not itself affect the T-helper subset skewing of the cells. Preliminary experiments showed a trend toward Th2 skewing for the high avidity Th2 CD4+ T cells having an engineered TCR when they were cultured under either Th1 or Th2 polarizing conditions and stimulated with the C2 peptide, compared to the phenotypes obtained following stimulation of polyclonal CD4 T cells with anti-CD3. These studies will improve our designing of engineered TCRs for CD4+T-cell therapy, especially when concerns of T-helper effector function and plasticity are important to clinical outcomes. Supported by NIH RO1-HL061883 (DWS), funding from Bayer and CSL Behring (KPP) and intramural support from NIAID (EMS). We thank Dr. Arthur Thompson (Puget Sound Blood Center) for enrolling patients and we thank all blood donors. Disclosures No relevant conflicts of interest to declare.


2020 ◽  
Author(s):  
Shiyu Wang ◽  
Longlong Wang ◽  
Ya Liu

AbstractCD4+ T cells are key components of adaptive immunity. The cell differentiation equips CD4+ T cells with new functions. However, the effect of cell differentiation on T cell receptor (TCR) repertoire is not investigated. Here, we examined the features of TCR beta (TCRB) repertoire of the top clones within naïve, memory and regular T cell (Treg) subsets: repertoire structure, gene usage, length distribution and sequence composition. First, we found that memory subsets and Treg would be discriminated from naïve by the features of TCRB repertoire. Second, we found that the correlations between the features of memory subsets and naïve were positively related to differentiation levels of memory subsets. Third, we found that public clones presented a reduced proportion and a skewed sequence composition in differentiated subsets. Furthermore, we found that public clones led naïve to recognize a broader spectrum of antigens than other subsets. Our findings suggest that TCRB repertoire of CD4+ T cell subsets is skewed in a differentiation-depended manner. Our findings show that the variations of public clones contribute to these changes. Our findings indicate that the reduce of public clones in differentiation trim the antigen specificity of CD4+ T cells. The study unveils the physiological effect of memory formation and facilitates the selection of proper CD4+ subset for cellular therapy.


2001 ◽  
Vol 194 (6) ◽  
pp. 719-732 ◽  
Author(s):  
Saied Mirshahidi ◽  
Ching-Tai Huang ◽  
Scheherazade Sadegh-Nasseri

Induction of tolerance in self-reactive memory T cells is an important process in the prevention of autoimmune responses against peripheral self-antigens in autoimmune diseases. Although naive T cells can readily be tolerized, memory T cells are less susceptible to tolerance induction. Recently, we demonstrated that low avidity engagement of T cell receptor (TCR) by low densities of agonist peptides induced anergy in T cell clones. Since memory T cells are more responsive to lower antigenic stimulation, we hypothesized that a low avidity TCR engagement may induce tolerance in memory T cells. We have explored two antigenic systems in two transgenic mouse models, and have tracked specific T cells that are primed and show memory phenotype. We demonstrate that memory CD4+ T cells can be rendered anergic by presentation of low densities of agonist peptide–major histocompatibility complex complexes in vivo. We rule out other commonly accepted mechanisms for induction of T cell tolerance in vivo, such as deletion, ignorance, or immunosuppression. Anergy is the most likely mechanism because addition of interleukin 2–reversed anergy in specific T cells. Moreover, cytotoxic T lymphocyte antigen (CTLA)-4 plays a critical role in the induction of anergy because we observed that there was increased surface expression of CTLA-4 on anergized T cells, and that injection of anti–CTLA-4 blocking antibody restored anergy in vivo.


Blood ◽  
2011 ◽  
Vol 117 (4) ◽  
pp. 1218-1227 ◽  
Author(s):  
Xiongfei Xu ◽  
Zhenhong Guo ◽  
Xueyu Jiang ◽  
Yushi Yao ◽  
Qiangguo Gao ◽  
...  

Abstract The heterogeneity and mechanisms for the generation of CD4 memory T (CD4 Tm) cells remain elusive. Distinct subsets of dendritic cells (DCs) have been found to regulate a distinct T-helper (Th)–cell subset differentiation by influencing cytokine cues around CD4 T cells; however, whether and how the regulatory DC subset can regulate Tm-cell differentiation remains unknown. Further, there is no ideal in vitro experimental system with which to mimic the 3 phases of the CD4 T-cell immune response (expansion, contraction, memory generation) and/or to culture CD4 Tm cells for more than a month. By analyzing CD4 T cells programmed by long-term coculture with regulatory DCs, we identified a population of long-lived CD4 T cells with a CD44hiCD62L−CCR7− effector memory phenotype and rapid, preferential secretion of the Th2 cytokines interleukin-4 (IL-4), IL-5, IL-10, and IL-13 after antigenic stimulation. These regulatory DC-programmed Tm cells suppress CD4 T-cell activation and proliferation in vitro via IL-10 and inhibit the delayed-type hypersensitivity response once infused in vivo. We also identify their natural counterpart, which is up-regulated by regulatory DC transfusion and negatively regulates the recall response in vivo. Different from interferon-γ–producing conventional Tm cells, these IL-4–producing CD4 Tm cells act as alternative Tm cells with a regulatory function, suggesting a new way of negative immune regulation by memory T cells.


2020 ◽  
Author(s):  
Menghua Lyu ◽  
Shiyu Wang ◽  
Kai Gao ◽  
Longlong Wang ◽  
Bin Li ◽  
...  

AbstractCD4 T cell is crucial in CMV infection, but its role is still unclear during this process. Here, we present a single-cell RNA-seq together with T cell receptor (TCR) sequencing to screen the heterogenicity and potential function of CMV pp65 reactivated CD4+ T cell subsets from human peripheral blood, and unveil their potential interactions. Notably, Treg composed the major part of these reactivated cells. Treg gene expression data revealed multiple transcripts of both inflammatory and inhibitory functions. Additionally, we describe the detailed phenotypes of CMV-reactivated effector-memory (Tem), cytotoxic T (CTL), and naïve T cells at the single-cell resolution, and implied the direct derivation of CTL from naïve CD4+ T cells. By analyzing the TCR repertoire, we identified a clonality in stimulated Tem and CTLs, and a tight relationship of Tem and CTL showing a large share in TCR. This study provides clues for understanding the function of CD4+ T cells subsets and unveils their interaction in CMV infection, and may promote the development of CMV immunotherapy.


Blood ◽  
1998 ◽  
Vol 92 (10) ◽  
pp. 3737-3744 ◽  
Author(s):  
Johan Grunewald ◽  
Eva Halapi ◽  
Jan Wahlström ◽  
Ricardo Giscombe ◽  
Soniya Nityanand ◽  
...  

T lymphocytes are implicated in the pathogenesis of systemic vasculitis such as Wegener’s granulomatosis (WG) and polyarteritis nodosa (PAN). In the present study, we have characterized in detail the T-cell receptor (TCR) of peripheral blood T cells from eight vasculitis patients of known HLA class II genotypes. We used flow cytometry to outline the exact TCR V gene expression, complementarity determining region 3 (CDR3) fragment analysis to estimate the degree of clonality and cDNA sequencing to define the exact TCR  or β chain sequences. The TCR CDR3 region interacts with antigenic peptides presented by HLA molecules, and it is normally immensely diverse. It was therefore of particular interest to identify a common dominating TCR BV8-F/L-G-G-A/Q-G-J2S3 β chain sequence in the CD4+T cells of four unrelated vasculitis patients. Furthermore, this BV8-associated CDR3 motif was linked to the HLA-DRB1*0401 allele, as well as to active disease and/or an established BV8+ CD4+ T-cell expansion. In contrast, age- and HLA-matched patients with rheumatoid arthritis did not harbor the described BV8 motif. These results strongly suggest that BV8+ CD4+ T cells with the described CDR3 motif recognize a specific antigen presented by DR4 molecules, indicating the existence of a common vasculitis-associated antigen.


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