Project description:Antigen-specific effector CD8+ T cells deficient in Blimp-1 (Prdm1) do not acquire maximal effector functions, evade terminal differentiation, and more rapidly acquire some hallmark properties of memory CD8+ T cells. In this study, we compared the gene expression profiles of wildtype and Prdm1-/- LCMV-specific effector CD8+ T cells to better understand the molecular mechanisms underlying this striking phenotype. DNA microarray analysis was performed of DbGP33-41 and DbNP396-404 tetramer-positive effector CD8+ T cells FACS-sorted at day 8 post-LCMV infection from four independent samples of either Blimp-1 conditional knockout mice (CKO; Blimp-1flox/flox x GranzymeB-cre+) or wildtype (WT) littermate controls.
Project description:Antigen-specific effector CD8+ T cells deficient in Blimp-1 (Prdm1) do not acquire maximal effector functions, evade terminal differentiation, and more rapidly acquire some hallmark properties of memory CD8+ T cells. In this study, we compared the gene expression profiles of wildtype and Prdm1-/- LCMV-specific effector CD8+ T cells to better understand the molecular mechanisms underlying this striking phenotype.
Project description:Blimp-1 regulates the overall accumulation of virus-specific CD8+ T cells during acute viral infections. Increased proliferation and survival of Blimp-1-deficient CD8+ T cells is promoted by persistent cytokine responsiveness, resulting from sustained expression of CD25 and CD27. Knockdown of these genes reduced the Blimp-1-deficient CD8+ T cell response. Genome-wide ChIP-sequencing analysis identified CD25 and CD27 genes as direct targets of Blimp-1. At the peak of the anti-viral response, but not earlier, Blimp-1 recruited the histone modifying enzymes G9a and HDAC2 to the Il2ra and Cd27 loci, thereby repressing expression of these genes. In the absence of Blimp-1, the Il2ra and Cd27 genes exhibited enhanced histone H3-acetylation and reduced histone H3K9-trimethylation. These data elucidate a central mechanism by which Blimp-1 acts as an epigenetic regulator, enhancing the numbers of short-lived effector cells while suppressing the development of memory precursor CD8+ T cells. NaM-CM-/ve CD8+ T cells from OT-I TCR transgenic Rag1-/- mice were stimulated with anti-CD3 and anti-CD28 for three days in vitro, in the presence of IL-2 to up-regulate Blimp-1 protein. Genome-wide mapping of Blimp-1 binding in mouse CD8+ T cells was conducted.
Project description:Blimp-1 regulates the overall accumulation of virus-specific CD8+ T cells during acute viral infections. Increased proliferation and survival of Blimp-1-deficient CD8+ T cells is promoted by persistent cytokine responsiveness, resulting from sustained expression of CD25 and CD27. Knockdown of these genes reduced the Blimp-1-deficient CD8+ T cell response. Genome-wide ChIP-sequencing analysis identified CD25 and CD27 genes as direct targets of Blimp-1. At the peak of the anti-viral response, but not earlier, Blimp-1 recruited the histone modifying enzymes G9a and HDAC2 to the Il2ra and Cd27 loci, thereby repressing expression of these genes. In the absence of Blimp-1, the Il2ra and Cd27 genes exhibited enhanced histone H3-acetylation and reduced histone H3K9-trimethylation. These data elucidate a central mechanism by which Blimp-1 acts as an epigenetic regulator, enhancing the numbers of short-lived effector cells while suppressing the development of memory precursor CD8+ T cells.
Project description:At the peak of the CD8 T cell response to acture viral and bacterial infections, expression of the Interleukin-7 Receptor (IL-7R) marks Memory Precursor Effector CD8 T Cells (MPECs) from other Short-Lived Effector CD8 T cells (SLECs), which are IL-7Rlo. This study was designed to determine the gene expression differences between these two subsets of effector CD8 T cells. Experiment Overall Design: This study compared IL-7Rhi and IL-7Rlo LCMV-specific P14 Transgenic CD8 T cells, sorted from LCMV armstrong infected recipient mice 6/7 days after infection. Data includes 3 independent replicates for the IL-7Rhi and IL-7Rlo groups.
Project description:Comparison of transcriptome between early Tfh vs. early Th1 cells Blimp-1-YFP LCMV gp specific TCRtg Smarta cells were transferred into B6 mice, which were then infected with LCMV Armstrong. On day 3 after infection, splenocytes were stained to sort Blimp-1-YFP+IL-2Ra+ Th1 cells or Blimp-1-YFP-IL-2Ra- Tfh cells for RNAseq analysis. Contributor: LIAI RNAi center (LIAI)
Project description:The transcription factor BATF is required for Th17 and TFH differentiation. Here, we show that BATF also has a fundamental role in regulating effector CD8+ T cell differentiation. BATF-deficient CD8+ T cells show profound defects in effector expansion and undergo proliferative and metabolic catastrophe early after antigen encounter. BATF, together with IRF4 and Jun proteins, binds to and promotes early expression of genes encoding lineage-specific transcription-factors (T-bet and Blimp-1) and cytokine receptors, while paradoxically repressing genes encoding effector molecules (IFNg and granzyme B). Thus, BATF amplifies TCR-dependent transcription factor expression and augments inflammatory signal propagation but restrains effector gene expression. This checkpoint prevents irreversible commitment to an effector fate until a critical threshold of downstream transcriptional activity has been achieved. P14 TCR transgenic CD8+ T cells from wild-type or BATF-/- mice were examined either as naïve cells or after 3 days of in vitro stimulation with antibodies to CD3 and CD28 in the presence of IL-2
Project description:The transcription factor BATF is required for Th17 and TFH differentiation. Here, we show that BATF also has a fundamental role in regulating effector CD8+ T cell differentiation. BATF-deficient CD8+ T cells show profound defects in effector expansion and undergo proliferative and metabolic catastrophe early after antigen encounter. BATF, together with IRF4 and Jun proteins, binds to and promotes early expression of genes encoding lineage-specific transcription-factors (T-bet and Blimp-1) and cytokine receptors, while paradoxically repressing genes encoding effector molecules (IFNg and granzyme B). Thus, BATF amplifies TCR-dependent transcription factor expression and augments inflammatory signal propagation but restrains effector gene expression. This checkpoint prevents irreversible commitment to an effector fate until a critical threshold of downstream transcriptional activity has been achieved. This is an examination of 5 different transcription factors (TFs) with 5 different histone modifications in effector CD8+ T cells. Two of the TFs (BATF and IRF4) and the histone modifications were replicated. Appropriate control sequence files for ChIP input, IgG ChIP, and Total H3 are also included.
Project description:p38 MAPK is activated during CD8+ T cell primary response. p38 activation promotes effector CD8+ T cell terminal differentiation but represses MPEC formation. p38α/beta deficient mice possess a similar number of virus-specific effector CD8+ T cells as wildtype counterparts. Meanwhile p38α/beta deletion doesn’t influence the clearance of LCMV although it impairs the cytolytic activity of CD8+ T cells. Loss of p38α/beta significantly enhances IL-2-producing Tcm accumulation in mouse spleen with no impact on total memory CD8+ T cell numbers yet. And in line with this, more robust proliferation of memory CD8+ T cells in the secondary response and stronger antigen-specific killing ability in rechallenged mice are resulted from p38α/beta deficiency. These results establish a pivotal role for p38α/beta in skewing MPEC formation toward SLEC differentiation, as well as in suppressing Tcm formation, and thus affecting the recall response.
Project description:Microarray analyses was employed to determine the gene expression profiles of LCMV-specific p14 CD8+ effector T cells eight days after an acute LCMV Armstrong infection providing a framework to compare and contrast effector function potential of distinct immune cell subsets to CD8+ effector T cells.