Project description:The pleiotropic cytokine IL-27 is essential for the clearance of the persistent LCMV strain Clone 13, however the cellular sources of IL-27 during viral infection are incompletely mapped and their relative importance unknown. Here we utilised single-cell RNA-sequencing of splenocytes from IL27-p28-GFP mice infected with Clone 13 to quantify the temporal patterns of IL-27 p28 production. IL-27-p28-GFP+ and IL-27-p28-GFP- splenocytes were sorted at 4 timepoints during Clone 13 infection and analysed by 3' single-cell transcriptome sequencing. Dendritic cells were major producers of early IL-27 with macrophages and monocytes being the predominant IL-27 producers during acute and persistent phases of infection. Interestingly, we also identified activated B cells and plasma cells as a prominent subset of IL-27-producing splenocytes and through B-cell-specific deletion of IL-27-p28 demonstrated that B-cell derived IL-27 is essential for sustained function of CD4 T cells and eventual clearance of Clone 13.
Project description:Altered CD8 T cell differentiation and functional exhaustion prevent control of chronic virus infection and cancer. Yet, how fate commitment and exhaustion are determined and dynamically modulated throughout persistent infection are unclear. We compared the activation and differentiation of LCMV GP33-specific CD8 TCR transgenic cells (P14) primed at the onset versus in the midst of established persistent LCMV-Clone 13 viral infection. LCMV GP33-specific CD8 TCR transgenic (P14) cells were injected into naïve mice immediately infected with LCMV-Cl13 (Early priming) or into mice that had been infected 21 days earlier with LCMV-Cl13 (Late Priming). Sixty hours post-priming P14 cells were sorted from mice and subjected to RNA seq. We show early primed cells very rapidly exhibit a transcriptional profile of robust activation, effector differentiation and dysfunction, while late primed cells have increased expression of genes involved in memory differentiation and maintenance.
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.
Project description:We report the transcriptome of subsets of mouse splenic mesenchymal reticular cells and lymph node reticular cells obtained from healthy Ccl19-cre x R26R-EYFP mice on a C57BL/6 background. We also examine splenic reticular cells from these mice infected with lymphocytic choriomeningitis virus (LCMV) strain Armstrong (acute infection) or strain Clone 13 (chronic infection). Subsets of CD45- CD31- Ter119- reticular cells were analyzed including PDPN+ T zone reticular cells (TRC) and MAdCAM-1+ marginal reticular cells (MRC) from spleen and lymph nodes. Additionally from the spleen we analyzed PDPN+ CD140a- cells, PDPN+ EYFP- cells, and EYFP+ red pulp reticular cells (RPRC) in healthy mice. We analyzed TRC, MRC, PDPN+ EYFP- cells, and EYFP+ RPRC from mice infected with LCMV Armstrong or LCMV Clone-13 on day 8 or on day 30 after infection. Our study represents the first detailed analysis of splenic reticular cell transcriptomes in healthy and LCMV-infected mice, with biologic replicates, generated by RNA-sequencing. We find substantial differential gene expression across subsets of splenic and lymph node reticular cells. We reveal significant changes in gene expression induced after virus infection that differ markedly with disease.
Project description:LCMV Clone 13 is an arenavirus that results in a persistent viral infection in mice when delivered intravenously. It has been widely used to explore the impact of chronic viral infection on CD4 T cell responses and dissect mechanisms that regulate this. In this study we used mixed bone marrow chimeras from wildtype and cytokine reeptor deficient (gp130 or IL-6/IL-27R) mice to determine the role these cytokines on splenic CD4 T cell responses 30 days post infection
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.
Project description:CD4 T cells promote innate and adaptive immune responses, but how vaccine-elicited CD4 T cells contribute to immune protection remains unclear. Here we evaluated whether induction of virus-specific CD4 T cells by vaccination would protect mice against infection with chronic lymphocytic choriomeningitis virus (LCMV). Immunization with vaccines that selectively induced CD4 T cell responses resulted in catastrophic inflammation and mortality following challenge with a persistent form of LCMV. Immunopathology required antigen-specific CD4 T cells and was associated with a cytokine storm, generalized inflammation, and multi-organ system failure. Virus-specific CD8 T cells or antibodies abrogated the pathology. These data demonstrate that vaccine-elicited CD4 T cells in the absence of effective antiviral immune responses can trigger lethal immunopathology. Splenic GP66-specific CD4 T cells from mice immunized with either a LMwt vaccine (sham) or LMgp61 vaccine (CD4 vaccine) were purified by FACS on day 8 post-infection with LCMV clone 13
Project description:The experimental data indicate that during a persistent infection, lymphocytic choriomeningitis virus (LCMV) may both directly or indirectly modulate the regulatory cellular processes and alter the cellular functions that are not critical for the survival, but are needed for the homeostasis in the organism. Two-dimensional differential in-gel electrophoresis (2D-DIGE) and MALDI-TOF MS/MS analyses were used to determine the cellular proteome response of HeLa cell line to persistent LCMV infection. Quantitative analysis revealed 24 differentially abundant proteins, half of which were up-regulated and the rest down-regulated. Functional categorization showed that LCMV-responsive proteins were mainly involved in metabolism, stress and defense responses. Among identified proteins, significant changes were found for peroxiredoxins, family of antioxidant enzymes. Decreased amount of these antioxidant proteins was accompanied with the elevation of ROS content in infected cells.
Project description:To identify mechanisms behind immunosuppression during virus infections, we infected mice with LCMV-Armstrong and LCMV-Clone 13 expression patterns. LCMV-Armstrong induces a T-cell reaction that resolves infection within 8-10 days, while LCMV-Clone13 generates a persisten infection through immunosuppression. We used microarray to uncover splenic gene expression patterns specific to each LCMV infection at 5, 9, and 30 days C57BL6 mice, 6-10 weeks old, were infected with LCMV-Armstrong and LCMV-Clone 13 or left uninfected (naïve). At days 5, 9, and 30 whole spleens were harvested for RNA extraction and hybridization on Affymetric microarray.
Project description:To identify mechanisms behind immunosuppression during virus infections, we infected mice with LCMV-Armstrong and LCMV-Clone 13 expression patterns. LCMV-Armstrong induces a T-cell reaction that resolves infection within 8-10 days, while LCMV-Clone13 generates a persisten infection through immunosuppression. We used microarray to uncover splenic gene expression patterns specific to each LCMV infection at 5, 9, and 30 days