Single cell profiling of CD4+ T cells from human fetal intestine
ABSTRACT: The fetus is thought to be protected from exposure to foreign antigens, yet CD45RO+ T-cells reside in the fetal intestine. We combined functional assays with mass cytometry, single-cell RNA-sequencing, and high-throughput TCR-sequencing to characterize the fetal intestinal CD4+ T-cell compartment. We identified 22 CD4+ T-cell clusters, including naive-like, regulatory-like, and memory-like subpopulations, which were confirmed and further characterized at the transcriptional level. Memory-like cells expressed high levels of Ki-67, indicating cell division, and CD5, a surrogate marker of TCR-avidity, and produced IFN-γ and IL-2. Pathway analysis revealed a differentiation trajectory associated with cellular activation and proinflammatory effector functions, and TCR-repertoire analysis demonstrated clonal expansions, distinct repertoire characteristics, and interconnections between subpopulations of memory-like CD4+ T-cells. Imaging-mass cytometry further showed that memory-like CD4+ T-cells colocalized with antigen-presenting cells. Collectively, these results provided evidence for the generation of memory-like CD4+ T-cells in the human fetal intestine, consistent with exposure to foreign antigens. Overall design: Single, live, CD3+CD8a–TCRγδ–CD4+/– T-cells from one human fetal intestines were processed on the Chromium 3' single cell platform (10x Genomics) and sequenced on an Illumina HiSeq 4000.
Project description:In this study, we show that in addition to regulating DP thymocytes survival, RORgT also controls genes that regulate thymocyte migration, proliferation, and T cell receptor (TCR) selection. Strikingly, pharmacological inhibition of RORg skews TCR gene rearrangement, limits T cell repertoire diversity, and inhibits development of autoimmune encephalomyelitis. Thus, targeting RORgT not only inhibits Th17 cell development and function but also fundamentally alters thymic-emigrant recognition of self and foreign antigens. Overall design: Examination of RORgT-bound genomic sites in C57BL/6 mouse thymocytes.
Project description:The TCR repertoire of CD4+ T cells in human lymph nodes is a case-based analysis of the TCR repertoire of CD4+ T cells in human lymph nodes. The study aims to determine how HIV infection alters the repertoire complexity of follicular helper T cells (TFH) in relationship to other T cell subsets in the lymphoid compartment. This study performs TCR repertoire sequencing using Molecular Identifier Clustering-based Immune Repertoire Sequencing (MIDCIRS). We found TFH cells become clonally expanded and convergently selected in LNs from patients with chronic HIV infection.
Project description:The High dimensional analyses of CD4+ T cells in human lymph nodes is a case-based analysis of the TCR repertoire, transcriptome, and epigenetic signatures of various CD4+ T cells in human lymph nodes. The study aims to determine clonal overlap between phenotypically distinct CD4+ T cells and the similarities between these populations on transcriptional and epigenetic levels. This study performs TCR repertoire sequencing using Molecular Identifier Clustering-based Immune Repertoire Sequencing (MIDCIRS). We found clonal overlap between a population of CXCR5- T cells and Tfh cells. We also show epigenetic and transcriptional similarities between CXCR5-PD-1+ T cells and Tfh cells.
Project description:CD4 T follicular helper (Tfh) cells provide the required signals to B cells for germinal center reactions that are necessary for longlived antibody responses. However, it remains unclear whether there are CD4+ memory T cells committed to the Tfh lineage after antigen clearance. Using adoptive transfer of antigen-specific memory CD4+ subpopulations (based on CXCR5 and Ly6c expression)in the LCMV infection model, we found that there are distinct memory CD4+ T cell populations with commitment to the Tfh and Th1 lineages. Our conclusions are based on gene expression profiles, epigenetic studies and phenotypic and functional analysis. The gene expression profiles of virus-specific CD4 T cell subets at effector and memory stages is presented here. The SMARTA TCR transgenic / adptive transfer system was used to identify and sort subsets of antigen-specific CD4 T cells (based on their expression of Ly6c and CXCR5) elicited after acute infection with LCMV (Arm).
Project description:To investigate the influence of CNS3, a cis-regulatory element in the Foxp3 locus, on the selection of T cell antigen receptor (TCR) repertoire of regulator CD4+ T cells (Treg), we crossed Foxp3ΔCNS3-gfp or control Foxp3gfp mice to DO11.10 TCRβ transgene and Tcra-/+ background. We isolated Treg and conventional CD4+T cells from thymus, spleen and lymph nodes of Foxp3ΔCNS3-gfp DO11.10 TCRβ Tcra-/+ or Foxp3gfp DO11.10 TCRβ Tcra-/+ male littermates, and sequenced the TCRα chains. Analysis of the diversity of Complementary Determining Region 3 (CDR3) of TCRα showed a distinct clustering of CNS3-deficient Treg cells from the CNS3-sufficient ones. Overall design: DO11.10 TCRβ transgene inhibits the recombination of endogenous Tcrb loci thus restricting TCR repertoire to TCRα chains expressed by T cells. Further limitation of the TCR repertoire was achieved by the presence of one functional Tcra gene. With restricted TCR repertoire, mRNA of TCRα was extracted from Treg and conventional CD4+ T cells for library preparation and high throughput sequencing.
Project description:We designed a lineage tracing method to label a wave of T cells produced in the thymus of young. TCR repertoire analysis revealed that the lineage-tracked CD4 memory-like T cells and T regulatory cells exhibited age-dependent enrichment of shared clonotypes, indicating that antigen matched T regulatory cells are involved in maintaining the tolerant status of long-lived T cell clones. Furthermore, these shared clonotypes were found across different mice maintained in the same housing condition mice. Examination of antigen-specificity of aging-tracking T-cell subtype.
Project description:Ag recognition via the TCR is necessary for the expansion of specific T cells that then contribute to adaptive immunity as effector and memory cells. Because CD4+ and CD8+ T cells differ in terms of their priming APCs and MHC ligands we compared their requirements of Ag persistence during their expansion phase side by side. Proliferation and effector differentiation of TCR transgenic and polyclonal mouse T cells were thus analyzed after transient and continuous TCR signals. Following equally strong stimulation, CD4+ T cell proliferation depended on prolonged Ag presence, whereas CD8+ T cells were able to divide and differentiate into effector cells despite discontinued Ag presentation. CD4+ T cell proliferation was neither affected by Th lineage or memory differentiation nor blocked by coinhibitory signals or missing inflammatory stimuli. Continued CD8+ T cell proliferation was truly independent of self-peptide/MHC-derived signals. The subset divergence was also illustrated by surprisingly broad transcriptional differences supporting a stronger propensity of CD8+ T cells to programmed expansion. These T cell data indicate an intrinsic difference between CD4+ and CD8+ T cells regarding the processing of TCR signals for proliferation. We also found that the presentation of a MHC class II–restricted peptide is more efficiently prolonged by dendritic cell activation in vivo than a class I bound one. In summary, our data demonstrate that CD4+ T cells require continuous stimulation for clonal expansion, whereas CD8+ T cells can divide following a much shorter TCR signal. Overall design: Samples 1-12: Analysis on day 2. Purified CD4+ AND-TCR transgenic cells and CD8+ OT1-TCR transgenic cells were separately stimulated with anti-CD3 and anti-CD28 antibodies. 48 hours later, the cells were sorted again to a purity of >99 %. Extracted total RNA was amplified twice and hybridized on Affymetrix Mouse 430A2 microarrays. First, we analysed the changes of the CD4+ and CD8+ T cells after stimulation. Second, we compared the differences of the changes between the two cell types after stimulation. For each of the four groups (CD4+ and CD8+, stimulated and unstimulated), we analysed three independent biological replicates. Samples 13-28: Analysis on day 5. AND and OT1 TCR-transgenic T cells were prepared as described before, but transferred into mice that do not or do present their respective antigens. 72 hours later, the cells were FACS-sorted twice to >99 % purity, directly into Trizol. For each of the six groups (CD4+ and CD8+, unstimulated, transient (2 days) and continuous (5 days) stimulation), three independent biological replicates were analyzed, except for CD4+ unstimulated and CD4+ transient, with two replicates each.
Project description:Oral tolerance prevents pathological inflammatory responses towards innocuous foreign antigens via peripheral regulatory T cells (pTreg cells). However, whether a particular subset of antigen-presenting cells (APCs) is required during dietary antigen exposure to instruct naïve CD4+ T cells to differentiate into pTreg cells has not been defined. Using myeloid lineage-specific APC depletion in mice, we found that monocyte-derived APCs are dispensable, while classical dendritic cells (cDCs) are critical for pTreg cell induction and oral tolerance. CD11b¬– cDCs from the gut-draining lymph nodes efficiently induced pTreg cells, and conversely, loss of IRF8-dependent CD11b– cDCs impaired their polarization, although oral tolerance remained intact. These data reveal the hierarchy of cDC subsets in pTreg cell induction and their redundancy during oral tolerance development. Sorted naïve CD45.1 OT-II CD4 T cells were co-cultured with four dendritic cell subpopulations sorted from mouse mesenteric lymphnodes. 24h later OT-II cells were sorted again and compared in their gene expression profile.
Project description:CD8+T cells are immune cells that recognize foreign antigens on infected and tumor cells, leading to cytokine-dependent expansion and activation of cytotoxicity towards the targets. To identify Runx3 regulated genes, CD8+ T cells were isolated from spleen of WT and Runx3-/- mice . Six samples (3 WT and 3 Runx3-/-) of CD8+ T cells were separately obtained from individual mice, TCR activated and cultured for 4 days with IL-2.
Project description:Islet-reactive T cells found in peripheral blood of type 1 diabetes (T1D) subjects are thought to be involved in disease pathogenesis, but full understanding of their role is complicated by their presence also in blood of in healthy subjects. To elucidate their role in T1D, we have combined flow cytometry and single cell RNA sequencing (RNA-seq) techniques to link prior antigen exposure, inferred from expanded TCR clonotypes, and functional capacities of islet antigen-reactive CD4+ memory T cells. We find that cells activated by pooled peptides from immunodominant islet antigens showed significantly higher clonotype sharing within recent onset T1D subjects than in healthy individuals, consistent with in vivo T cell expansion during disease progression. There was no clonotype sharing between donors, indicating a predominance of TCRs with distinct or “private” specificities. Expanded clonotypes could be stable, as one was detected at repeat visits by spanning more than a year by one subject. We identified distinct IGRP peptides as the targets of expanded TCR clonotypes from two T1D subjects, thereby implicating this molecule as a trigger for CD4+ T cell expansion during T1D. Transcriptome profiles of cells from T1D and healthy subjects differed, particularly in cells having the most highly expanded TCR clonotypes. As a group, cells with the most highly expanded TCR clonotypes showed Th2-like phenotypes, but at the single cell level there was phenotypic heterogeneity within and between donors. Our findings demonstrate unique specificities and phenotypes of individual islet-reactive CD4+ memory T cells that have expanded during disease progression. Overall design: This project contains RNA-seq files from four cell types: 1) T cell clone (N=149 single cell profiles); 2) T cell clone (N=9 bulk cell profiles); 3) CD8+ influenza-reactive T cells (N=45 single cell profiles); and 4) CD4+ pooled islet antigen-reactive T cells (N=246 single cell profiles).