ABSTRACT: Type I Interferon induces binding of STAT1 to Bcl6: Divergent Roles of STAT-family transcription factors in the T follicular helper cell genetic program
Project description:CD4+ T follicular helper cells (TFH) are critical for the formation and function of B cell responses to infection or immunization, but also play an important role in autoimmunity. The factors that contribute to the differentiation of this helper cell subset are incompletely understood, although several cytokines including IL-6, IL-21 and IL-12 can promote TFH cell formation. Yet, none of these factors, nor their downstream cognate STATs, have emerged as non-redundant, essential drivers of TFH cells. This suggests a model in which multiple factors can contribute to the phenotypic characteristics of TFH cells. As type I interferons (IFNs) are often generated in immune responses, we set out to investigate if these factors are relevant to TFH cell differentiation. Type I IFNs promote Th1 responses, thus one possibility was these factors antagonized TFH-expressed genes. However, we show that type I IFNs (IFN-α/β) induced Bcl6 expression, the master regulator transcription factor for TFH cells, and CXCR5 and PD-1 (encoded by Pdcd1), key surface molecules expressed by TFH cells. In contrast, type I IFNs failed to induce IL-21, the signature cytokine for TFH cells. The induction of Bcl6 was regulated directly by STAT1, which bound to the Bcl6, Cxcr5 and Pdcd1 loci. These data suggest that type I IFNs (IFN-α/β) and STAT1 can contribute to some features of TFH cells but are inadequate in inducing complete programming of this subset. The role of STAT1 in type I interferon treated CD4+ T cells was investigated by Chip-seq of STAT1.
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.
Project description:U3A cells stably expressing wild-type STAT1 or STAT1-CC were treated with interferon beta (10U/ml) or control for 24 hours to assess effects of stat1 modifications, interferon, and the interaction on gene expression. Keywords: interferon, STAT1, STAT1-CC, STAT1CC, STAT-1C, antiviral RNA was isolated from stable U3A-STAT1 lines stably expressing wild-type STAT1 or STAT1CC, after 24 hour treatment with interferon beta (10U/ml) or control.
Project description:T follicular helper (Tfh) cells play a pivotal role in germinal center reactions, which requires Bcl6 transcription factor. To analyze their relationships with other effector T cell lineages and their stability in vivo, we developed and analyzed a new Bcl6 reporter mouse alone or together with other lineage reporter systems. Assisted with genome-wide transcriptome analysis, we show substantial plasticity of T cell differentiation in the early phase of immune response. At this stage, CXCR5 appears to be expressed in a Bcl6-independent manner. Once Bcl6 is highly expressed, Tfh cells can persist in vivo and some of them develop into memory cells. Together, our results indicate Bcl6 as a bona fide marker for Tfh polarized program. Three group of samples, with 2 biological replicates within each group and total of 6 samples were analyzed.
Project description:Gene expression data from wild-type and Bcl6-/- naive CD4 T cells In order to find genes regulated by Bcl6 in follicular helper T cells
Project description:Gene expression data from wild-type and Bcl6-/- naive CD4 T cells In order to find genes regulated by Bcl6 in follicular helper T cells
Project description:Gene expression data from wild-type and Bcl6-/- naive CD4 T cells In order to find genes regulated by Bcl6 in follicular helper T cells Naïve CD4 T cells were sorted from wild-type (WT) and T cell-specific conditional Bcl6-/- (KO) mice-- 8 samples, 4 WT and 4 KO
Project description:Gene expression data from wild-type and Bcl6-/- naive CD4 T cells In order to find genes regulated by Bcl6 in follicular helper T cells Naïve CD4 T cells were sorted from wild-type (WT) and T cell-specific conditional Bcl6-/- (KO) mice-- 8 samples, 4 WT and 4 KO
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).