Project description:Tet2-mediated demethylation is a key component of epigenetic programing that promotes lineage specific gene expression and contributes to cellular differentiation and function. While the differentiation of CD4+ T cell subsets has been studied extensively, the epigenetic programs that regulate these processes remain unclear. We report that Tet2 acts to restrict the differentiation of T follicular helper (Tfh) cells in CD4+ T cells responding to viral infection. Tet2-deficient CD4+ T cells preferentially differentiated into highly functional germinal center (GC) Tfh cells that provided enhanced help for B cell responses. Using genome-wide expression and methylation analyses combined with Foxo1 ChIPseq analysis, we found that Tet2 coordinates with multiple transcription factors, including Foxo1, to mediate the demethylation and expression of their target genes following activation.
Project description:Tet2-mediated demethylation is a key component of epigenetic programing that promotes lineage specific gene expression and contributes to cellular differentiation and function. While the differentiation of CD4+ T cell subsets has been studied extensively, the epigenetic programs that regulate these processes remain unclear. We report that Tet2 acts to restrict the differentiation of T follicular helper (Tfh) cells in CD4+ T cells responding to viral infection. Tet2-deficient CD4+ T cells preferentially differentiated into highly functional germinal center (GC) Tfh cells that provided enhanced help for B cell responses. Using genome-wide expression and methylation analyses combined with Foxo1 ChIPseq analysis, we found that Tet2 coordinates with multiple transcription factors, including Foxo1, to mediate the demethylation and expression of their target genes following activation.
Project description:Tet2-mediated demethylation is a key component of epigenetic programing that promotes lineage specific gene expression and contributes to cellular differentiation and function. While the differentiation of CD4+ T cell subsets has been studied extensively, the epigenetic programs that regulate these processes remain unclear. We report that Tet2 acts to restrict the differentiation of T follicular helper (Tfh) cells in CD4+ T cells responding to viral infection. Tet2-deficient CD4+ T cells preferentially differentiated into highly functional germinal center (GC) Tfh cells that provided enhanced help for B cell responses. Using genome-wide expression and methylation analyses combined with Foxo1 ChIPseq analysis, we found that Tet2 coordinates with multiple transcription factors, including Foxo1, to mediate the demethylation and expression of their target genes following activation.
Project description:Following viral clearance, antigen-specific CD4+ T cells contract and form a pool of distinct Th1 and Tfh memory cells that possess unique epigenetic programs, allowing them to rapidly recall their specific effector functions upon rechallenge. DNA methylation programing mediated by the methylcytosine dioxygenase Tet2 contributes to balancing Th1 and Tfh cell differentiation during acute viral infection, however the role of Tet2 in CD4+ T cell memory formation and recall is unclear. Using adoptive transfer models of antigen-specific WT andTet2KO CD4+ T cells, we find that Tet2 is required for full commitment of CD4+ T cells to the Th1 lineage and that in the absence of Tet2, memory cells preferentially recall a Tfh like phenotype with enhanced expansion upon secondary challenge. These findings demonstrate an important role for Tet2 in enforcing lineage commitment and programing proliferation potential, and highlight the potential of targeting epigenetic programing to enhance adaptive immune responses.
Project description:Analysis of in vivo antigen-specific (LCMV-specific, SMARTA TCR transgenic) follicular helper CD4 T cells (CXCR5high),versus non-follicular helper CD4 T cells (CXCR5low), eight days after viral infection. A paper including data analysis of these experiments has been accepted for publication (Robert J. Johnston et al. Bcl6 and Blimp-1 are reciprocal and antagonistic regulators of follicular helper CD4 T cell differentiation). Experiment Overall Design: Analysis of in vivo antigen-specific (LCMV-specific, SMARTA TCR transgenic) follicular helper CD4 T cells (CXCR5high), versus non-follicular helper CD4 T cells (CXCR5low), eight days after viral infection.