Project description:Following an infection, CD4+ lymphocytes can differentiate into long-lived memory T cells, some of which circulate through the secondary lymphoid organs (SLOs) while a population lodges in non-lymphoid tissues. While CD4+ T cells in SLOs have been examined, the developmental origins and transcriptional regulation of tissue-resident memory T cells (TRM) remain largely undefined. Here, we investigated the phenotypic, functional, and transcriptional profile of virus-specific CD4+ TRM in the small intestine (SI) following acute lymphocytic choriomeningitis virus (LCMV) infection. LCMV-specific CD4+ TRM at day 7 of infection shared a gene-expression program and chromatin profile with TH1 cells and progressively acquired a mature TRM program by day 21 memory time point, supporting a developmental relationship between TRM and TH1 subsets. Furthermore, we demonstrated that TRM cells expressed genes associated with both effector and memory T cell fates, including the transcriptional regulators Blimp1, Id2, and Bcl6 which were necessary for CD4+ TRM differentiation. TH1-associated Blimp1 and Id2 were both required for early TRM formation, while TFH-associated Bcl6 initially inhibited TRM differentiation but was critical for development of long-lived TRM cells. Our results identify new significance for TFs previously associated with circulating CD4+ T cell populations and their roles in driving SI CD4+ TRM differentiation.
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:Following an infection, CD4+ lymphocytes can differentiate into long-lived memory T cells, some of which circulate through the secondary lymphoid organs (SLOs) while a population lodges in non-lymphoid tissues. While CD4+ T cells in SLOs have been examined, the developmental origins and transcriptional regulation of tissue-resident memory T cells (TRM) remain largely undefined. Here, we investigated the phenotypic, functional, and transcriptional profile of virus-specific CD4+ TRM in the small intestine (SI) following acute lymphocytic choriomeningitis virus (LCMV) infection. LCMV-specific CD4+ TRM at day 7 of infection shared a gene-expression program and chromatin profile with TH1 cells and progressively acquired a mature TRM program by day 21 memory time point, supporting a developmental relationship between TRM and TH1 subsets. Furthermore, we demonstrated that TRM cells expressed genes associated with both effector and memory T cell fates, including the transcriptional regulators Blimp1, Id2, and Bcl6 which were necessary for CD4+ TRM differentiation. TH1-associated Blimp1 and Id2 were both required for early TRM formation, while TFH-associated Bcl6 initially inhibited TRM differentiation but was critical for development of long-lived TRM cells. Our results identify new significance for TFs previously associated with circulating CD4+ T cell populations and their roles in driving SI CD4+ TRM differentiation.
Project description:Following an infection, CD4+ lymphocytes can differentiate into long-lived memory T cells, some of which circulate through the secondary lymphoid organs (SLOs) while a population lodges in non-lymphoid tissues. While CD4+ T cells in SLOs have been examined, the developmental origins and transcriptional regulation of tissue-resident memory T cells (TRM) remain largely undefined. Here, we investigated the phenotypic, functional, and transcriptional profile of virus-specific CD4+ TRM in the small intestine (SI) following acute lymphocytic choriomeningitis virus (LCMV) infection. LCMV-specific CD4+ TRM at day 7 of infection shared a gene-expression program and chromatin profile with TH1 cells and progressively acquired a mature TRM program by day 21 memory time point, supporting a developmental relationship between TRM and TH1 subsets. Furthermore, we demonstrated that TRM cells expressed genes associated with both effector and memory T cell fates, including the transcriptional regulators Blimp1, Id2, and Bcl6 which were necessary for CD4+ TRM differentiation. TH1-associated Blimp1 and Id2 were both required for early TRM formation, while TFH-associated Bcl6 initially inhibited TRM differentiation but was critical for development of long-lived TRM cells. Our results identify new significance for TFs previously associated with circulating CD4+ T cell populations and their roles in driving SI CD4+ TRM differentiation.
Project description:CD4 and CD8 T cells display functional defects during chronic infection such as loss of certain cytokines. Recent studies have suggested that CD4 T cells may actually gain other functions, however. Here, we analyzed gene expression profiles from LCMV-specific CD4 and CD8 T cells throughout the response to either acute LCMV or chronic LCMV infection. This alllowed us to identify CD4-specific changes during chronic infection compared to acute infection but also revealed shared core regulators between CD4 and CD8 T cells. LCMV-specific CD4 and CD8 T cells were isolated 6, 8, 15 and 30 days post infection with LCMV Armstrong or LCMV clone 13. Naïve CD4 and CD8 T cells were also isolated from naïve mice as comparisons. Four replicates of each sample were hybridized. The only exception is LCMV-specific CD4 T cells isolated 6 days post infection with LCMV-Arm where only three replicates were hybridized.