Project description:Human Naïve-like CD8 T cells induced by the Yellow Fever Vaccine 17D were compared to the conventional subsets in total CD8 T cells Samples originate from peripheral blood mononuclear cells (PBMC) from 8 different donors vaccinated with the YF-17D vaccine 1'000 cells from various CD8 T cells subsets were purified by flow cytometry, from 8 vaccinees (donors d1 to d8); the subsets (cell types) include: A2/NS4b tetramer positive CCR7+ CD45RA+ CD8 T cells (A2_NS4b Naïve-like), Total Naive (CCR7+ CD45RA+), Total Tscm (CCR7+ CD45RA+ CD58+ CD95+), Total CM (CCR7+ CD45RA-) and Total Effectors (CCR7 negative).
Project description:A plethora of data supports a major role of CD4+ and CD8+ T lymphocytes for the initiation, progression and maintenance of allergic contact dermatitis (ACD). However, in-depth understanding of the underlying molecular mechanisms is still limited. NFATc1 , a central component of the Ca++-Calcineurin-NFAT-signalling network, plays an essential role in T cell activation. We therefore investigated its impact on contact hypersensitivity (CHS), the mouse model for ACD. The CHS response to 2,4,6-trinitrochlorobenzene (TNCB) was diminished in Nfatc1fl/flxCd4-cre mice (Nfatc1-/-) as compared to wild-type (WT) animals and associated with a lower percentage of interleukin (IL)17-producing CD8+T (Tc17) cells in both inflamed skin and draining lymph nodes (dLN). In vitro Tc17 polarization assays revealed that Nfatc1-/- CD8+ T cells have a reduced capacity to polarize into Tc17 cells. Applying single-cell RNA sequencing, we realized that NFATc1 controls the T cell differentiation fate. In the absence of NFATc1, CD8+ T cells favour the development of Interferon (IFN)-g-secreting CD8+ T (Tc1) lymphocytes while in its presence they turn into Tc17 cells. Finally, we showed the adoptive transfer of TNCB-sensitized WT CD8+T cells rescued tThe CHS response could be rescued in naïve Nfatc1-/-mice by adoptive transfer of TNCB-sensitized WT CD8+T cells. Our data demonstrate that NFATc1 acts as a molecular switch controllcontrolsing the development of Tc17 cells and can be used as a target to alleviate surveilling CD8+T cell-mediated CHS responses.
Project description:Biomaterials induce an immune response and mobilization of macrophages, yet identification and phenotypic characterization of functional macrophage subsets in vivo remain limited. We performed single-cell RNA sequencing analysis on macrophages sorted from either a biologic matrix [urinary bladder matrix (UBM)] or synthetic biomaterial [polycaprolactone (PCL)]. Implantation of UBM promotes tissue repair through generation of a tissue environment characterized by a T helper 2 (Th2)/interleukin (IL)–4 immune profile, whereas PCL induces a standard foreign body response characterized by Th17/IL-17 and fibrosis. Unbiased clustering and pseudotime analysis revealed distinct macrophage subsets responsible for antigen presentation, chemoattraction, and phagocytosis, as well as a small population with expression profiles of both dendritic cells and skeletal muscle after UBM implantation. In the PCL tissue environment, we identified a CD9 hi+ IL-36y + macrophage subset that expressed Th17-associated molecules. These macrophages were virtually absent in mice lacking the IL-17 receptor, suggesting that they might be involved in IL-17–dependent immune and autoimmune responses. Identification and comparison of the unique phenotypical and functional macrophage subsets in mouse and human tissue samples suggest broad relevance of the new classification. These distinct macrophage subsets demonstrate previously unrecognized myeloid phenotypes involved in different tissue responses and provide targets for potential therapeutic modulation in tissue repair and pathology.
Project description:miRNA profiling of Db-GP33-41 specific murine CD8 T cells following infection with LCMV Armstrong Various in-vivo subsets of antigen-specific CD8 T cells were FACS sorted and analyzed for miRNA expression profiling. Samples were purified from either uninfected animals or after days 4.5, 9 and >60 post infection with LCMV Armstrong.
Project description:Transcriptional profiling and gene expression profiling analysis of sorted CD8+IL-10+ T cells compared to CD8+IL-10- T cells using IL-10-GFP(tiger) reporter mice Two sample, CD8+IL-10+ T cells vs CD8+IL-10- T cells. Three replicate per array.
Project description:Innate CD8+ T cells are a heterogeneous population with developmental pathways distinct from conventional CD8+ T cells. Their biology, classification and functions remain incompletely understood. We recently demonstrated the existence of distinct populations of innate CD8+ T cells based on CXCR3 expression. We characterized these subsets through gene expression profiling and identified effector molecules and pathways which mediate their function.
Project description:We propose a novel role for interleukin (IL) 6 in inducing rapid spontaneous proliferation (SP) of naive CD8(+) T cells, which is a crucial step in the differentiation of colitogenic CD8(+) T cells. Homeostasis of T cells is regulated by two distinct modes of cell proliferation: major histocompatibility complex/antigen-driven rapid SP and IL-7/IL-15-dependent slow homeostatic proliferation. Using our novel model of CD8(+) T cell-dependent colitis, we found that SP of naive CD8(+) T cells is essential for inducing pathogenic cytokine-producing effector T cells. The rapid SP was predominantly induced in mesenteric lymph nodes (LNs) but not in peripheral LNs under the influence of intestinal flora and IL-6. Indeed, this SP was markedly inhibited by treatment with anti-IL-6 receptor monoclonal antibody (IL-6R mAb) or antibiotic-induced flora depletion, but not by anti-IL-7R mAb and/or in IL-15-deficient conditions. Concomitantly with the inhibition of SP, anti-IL-6R mAb significantly inhibited the induction of CD8(+) T cell-dependent autoimmune colitis. Notably, the transfer of naive CD8(+) T cells derived from IL-17(-/-) mice did not induce autoimmune colitis. Thus, we conclude that IL-6 signaling is crucial for SP under lymphopenic conditions, which subsequently caused severe IL-17-producing CD8(+) T cell-mediated autoimmune colitis. We suggest that anti-IL-6R mAb may become a promising strategy for the therapy of colitis.
Project description:IL-17 cytokine family members have diverse biological functions, promoting protective immunity against many pathogens but also driving inflammatory pathology during infection and autoimmunity. IL-17A and IL-17F are produced by CD4+ and CD8+ T cells, γδ T cells, and various innate immune cell populations in response to IL-1β and IL-23, and they mediate protective immunity against fungi and bacteria by promoting neutrophil recruitment, antimicrobial peptide production and enhanced barrier function. IL-17-driven inflammation is normally controlled by regulatory T cells and the anti-inflammatory cytokines IL-10, TGFβ and IL-35. However, if dysregulated, IL-17 responses can promote immunopathology in the context of infection or autoimmunity. Moreover, IL-17 has been implicated in the pathogenesis of many other disorders with an inflammatory basis, including cardiovascular and neurological diseases. Consequently, the IL-17 pathway is now a key drug target in many autoimmune and chronic inflammatory disorders; therapeutic monoclonal antibodies targeting IL-17A, both IL-17A and IL-17F, the IL-17 receptor, or IL-23 are highly effective in some of these diseases. However, new approaches are needed to specifically regulate IL-17-mediated immunopathology in chronic inflammation and autoimmunity without compromising protective immunity to infection.
Project description:Human Naïve-like CD8 T cells induced by the Yellow Fever Vaccine 17D were compared to the conventional subsets in total CD8 T cells Samples originate from peripheral blood mononuclear cells (PBMC) from 8 different donors vaccinated with the YF-17D vaccine
Project description:CD25, the high affinity interleukin-2 (IL-2) receptor alpha-chain, is rapidly upregulated by antigen-specific CD8+ T cells after T cell receptor stimulation. We demonstrated that during an acute viral infection, CD25 expression was dynamic, and a subset of virus-specific CD8+ T cells sustained CD25 expression longer than the rest. Examination of the in vivo fate of effector CD8+ T cells exhibiting differential responsiveness to IL-2 revealed that CD25lo cells, which were relatively less sensitive to IL-2, preferentially upregulated CD127 and CD62L and gave rise to the functional long-lived memory pool. In contrast, CD25hi cells that accumulate enhanced IL-2 signals, proliferated more rapidly, were prone to apoptosis, exhibited a more pronounced effector phenotype, and appeared to be terminally differentiated. Sustained IL-2 receptor signaling resulted in increased CD8+ T cell proliferation, higher granzyme B expression and exaggerated contraction after antigen clearance. These data support the hypothesis that prolonged IL-2 signals during priming promote terminal effector differentiation of CD8+ T cells. Experiment Overall Design: An important question in memory development is understanding the differences between effector CD8 T cells that die versus effector cells that survive and give rise to memory cells. In this study we have performed genomic profiling of terminal effectors and memory precursors as defined by CD25 heterogeneity, towards better understanding the generation of these subsets. The two effector subsets were FACS purified based on the amount of cell surface CD25 expression into CD25lo and CD25hi subsets during the early expansion phase (Days 3-4 post-infection) and analyzed for their gene expression profiles (by genome-wide microarray analyses).