Project description:Acute graft versus host disease is a serious condition caused by allo-reactive donor CD4+ T cells from allogenic hematopoietic stem cell transplantation. To understand the developmental relationships between T-helper states in mesenteric lymph nodes (mLN), TCR transgenic CD4+ T cells specific for a single allo-peptide (TEa cells) from mice were recovered at Days 0, 1, 2, 3, and 4 from mLN, and Day 5 from the gut and underwent processing to generate scRNA-seq dataset. TEa cells were also recovered at Day 5 from mLN and were either treated with and without IEL-isolation pre-digestion buffer as controls.
Project description:Plasmodium-specific CD4+ T cells from mice infected with Plasmodium chabaudi chabaudi AS parasites were recovered at Days 0, 7, and 28 to undergo processing and generate scRNA-seq dataset. At Day 28, mice were administered with either saline or artesunate (intermittent artesunate therapy - IAT). scRNA-seq dataset was analysed to investigate transcriptome dynamics of CD4+ T cells from effector to memory states.
Project description:Plasmodium-specific CD4+ T cells from mice infected with Plasmodium chabaudi chabaudi AS parasites were recovered at Days 0, 7, 10, 14, 17, 21, 28 to undergo processing and generate scRNA-seq dataset. From Day 10 onwards, mice were administered with either saline or artesunate (intermittent artesunate therapy - IAT). scRNA-seq dataset was analysed to investigate transcriptome dynamics of CD4+ T cells from effector to memory states.
Project description:The contribution of CD4+ T cells to protective or pathogenic immune responses to SARS-CoV-2 infection remains unknown. Here, we present a large-scale single-cell transcriptomic analysis of viral antigen-reactive CD4+ T cells from 40 COVID-19 patients. In hospitalized patients compared to non-hospitalized patients, we found increased proportions of cytotoxic follicular helper (TFH) cells and cytotoxic T helper cells (CD4-CTLs) responding to SARS-CoV-2, and reduced proportion of SARS-CoV-2-reactive regulatory T cells (TREG). Importantly, in hospitalized COVID-19 patients, a strong cytotoxic TFH response was observed early in the illness which correlated negatively with antibody levels to SARS-CoV-2 spike protein. Polyfunctional T helper (TH)1 and TH17 cell subsets were underrepresented in the repertoire of SARS-CoV-2-reactive CD4+ T cells compared to influenza-reactive CD4+ T cells. Together, our analyses provide so far unprecedented insights into the gene expression patterns of SARS-CoV-2-reactive CD4+ T cells in distinct disease severities.
Project description:scRNA-seq was performed and data generated to examine the transcriptomic differences between PD-1/CTLA4 double-positive and double-negative CD4+ T cells in HIV patients.
Project description:The transcription factor T Cell Factor-1 encoded by (TCF-7) is critical for T cell development. However, the role of TCF-7 on peripheral CD4 T cells mediated allo-immunity was not known. In this report using a clinically relevant model we presented novel finding of how TCF-7 regulates CD4 T cells functions, including CD4 T cells activation, proliferation, differentiation and impacts effector and central memory formation. We uncovered how TCF-7 regulates chemokine receptor which are essential for CD4 T cells migration to the site of inflammation. Our data uncovered how TCF-7 plays critical role in CD4 T cells survival, apoptosis. Using in vivo allo-immunity models and in-vitro studies we demonstrated how TCF-7 plays central role in CD4 T cells mediated damaged to organs like liver, skin and small intestine. We provided both molecular and biochemical and transcriptomic evidence how TCF-7 functionally regulates CD4 T cells mediated apoptosis and cell death, T cell mediated processes, pro-inflammatory and anti-inflammatory cytokines productions in both basal level and after allo-activation. These findings novel findings represent a stem forward to designing target specific approach for CD4 T cells mediated diseases while understand molecular mechanism the role of CD4 T cells in allo-immunity.
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.