Project description:We compared CD8 T cells specific for a CMV epitope (pp65495-503) and an influenza A virus (IAV) epitope (M158-66) of the same healthy adults and identified genes whose expression are altered in CMV-specific compared to IAV-specific TCM cells
Project description:We compared CD8 TCM cells specific for a CMV epitope (pp65495-503) and an influenza A virus (IAV) epitope (M158-66) of the same healthy adults and identified genes whose expression are altered in CMV-specific compared to IAV-specific TCM cells.
Project description:Reconstitution of cytomegalovirus (CMV)-specific immunity following transplant remains a primary clinical objective to prevent CMV disease, and adoptive immunotherapy of CMV-specific T cells can be an effective therapeutic approach. Due to the persistence of CMV, most CMV-specific CD8+ T cells become terminally differentiated effector cells (TEFF). However, a minor subset retains a memory phenotype (TM). Interestingly, recent studies suggest that CMV-specific CD8+ T cells with different phenotypes may have different abilities to reconstitute sustained immunity following transfer. The immunology of human CMV (HCMV) infections is reflected in the mouse model of MCMV infection. We found that HCMV- and MCMV-specific T cells displayed shared genetic programs, validating the MCMV model for studies of CMV-specific T cells in vivo. After transfer, the proliferative capacity of MCMV-specific TM cells was vastly superior to TEFF cells. Strikingly, TM cells expanded and established sustained and diverse T cell populations even after multiple challenges. Although both TEFF and TM cells could protect Rag-/- mice, only TM cells could consistently survive after transfer into immune replete, latently infected recipients and respond if recipient immunity was lost. These data show that CMV-specific TM cells retain memory function during persistent infection and can re-establish CMV immunity when necessary. C57BL/6 mice were infected intraperitoneally (i.p.) with MCMV strain MW97.01 between 6-16 weeks of age. Splenocytes were isolated from chronically-infected mice and co-stained with three PE-conjugated tetramers loaded with the antigenic peptides from M38, m139 and IE3, all of which promote memory inflation. Cells were then stained with fluorescently conjugated antibodies and sorted on a MoFlo cell sorter. Naïve CD8+ cells were identified as CD44lo. MCMV-specific T cells were identified as CD8+, CD44hi and tetramer binding and then further segregated into memory and effector cells subsets by their expression of KLRG1 and CD127.
Project description:Reconstitution of cytomegalovirus (CMV)-specific immunity following transplant remains a primary clinical objective to prevent CMV disease, and adoptive immunotherapy of CMV-specific T cells can be an effective therapeutic approach. Due to the persistence of CMV, most CMV-specific CD8+ T cells become terminally differentiated effector cells (TEFF). However, a minor subset retains a memory phenotype (TM). Interestingly, recent studies suggest that CMV-specific CD8+ T cells with different phenotypes may have different abilities to reconstitute sustained immunity following transfer. The immunology of human CMV (HCMV) infections is reflected in the mouse model of MCMV infection. We found that HCMV- and MCMV-specific T cells displayed shared genetic programs, validating the MCMV model for studies of CMV-specific T cells in vivo. After transfer, the proliferative capacity of MCMV-specific TM cells was vastly superior to TEFF cells. Strikingly, TM cells expanded and established sustained and diverse T cell populations even after multiple challenges. Although both TEFF and TM cells could protect Rag-/- mice, only TM cells could consistently survive after transfer into immune replete, latently infected recipients and respond if recipient immunity was lost. These data show that CMV-specific TM cells retain memory function during persistent infection and can re-establish CMV immunity when necessary.
Project description:Here we studied the transcriptional profile of virus specific CD8 T cells to gain molecular insights in CD8 T cell functionality in HIV infection. HIV- and CMV-specific CD8 T cells were isolated from HIV infected individuals participating in the Amsterdam Cohort Studies (HIV progressors, long-term non-progressors (LTNP; HLA-B*57 and non-HLA-B*57) and individuals carrying the MAVS minor genotype) and CMV seropositive blood donors (BD). The transcription profile of HIV-specific CD8 T cells of LTNP groups was associated with increased protein/RNA metabolism pathways, indicating that immune control of HIV infection in these individuals is associated with increased functionality. In contrast, CMV-specific CD8 T cells from progressors showed increased expression of genes related to effector functions and suggests recent CMV reactivation. Our study provides novel insights into molecular mechanisms involved in HIV and CMV control in chronic HIV infection.
Project description:We introduced single-chain trimer (SCT) technologies into a high throughput platform for pMHC library generation that can be used for screening antigen specific CD8+ T cells. We compared the diversity of T cell receptor repertoire captured by SCT and folded peptide-MHC multimer presenting HLA-A02:01 restricted CMV peptide. We then constructed SCT libraries designed to capture SARS-CoV-2 spike specific CD8+ T cells from COVID-19 participants and healthy donors. TCR sequencing with antigen specificity was analyzed. The immunogenicity of these epitopes was validated by functional assays of T cells with cloned TCRs captured using SCT libraries.
Project description:The liver is an immunologically unique organ in terms of the regulation of immuno-tolerance and immune responses. Recently, non-recirculating tissue-resident memory T (TRM) cells expressing CD69 were found in various peripheral organs. In humans, a large population of CD69+CD8+ memory T cells residing in liver sinusoids shows reduced cytotoxicity. However, the trascriptional characteristics of human liver CD8+ T cells are still unknown. Therefore, we performed a microarray analysis to screen the gene expression profile in liver sinusoidal CD8+ T cells using CMV-specific CD8+ T cells from human peripheral blood and liver sinusoid.
Project description:The CD8+ T cell compartment of human cytomegalovirus (CMV) seropositive individuals characteristically contains a high proportion of cells that expresses Natural Killer Cell Receptors (NKR) which may contribute to the surveillance of virus-infected cells. To test if this enhanced expression is a direct and immediate result of CMV infection we used DNA microarrays to analyse putative changes in RNA-expression level of 39 NKRs in CMV-specific CD8+ T cells of renal transplant recipients experiencing primary CMV infection. Already in the acute phase of infection 29 NKRs were induced of which 19 remained high 1 year after cessation of viral replication. Activating and inhibitory NKRs were induced to a similar extent. Detailed longitudinal flowcytometric analyses confirmed NKR changes at the protein level. Strikingly, a strong induction of CD94 on CD3+ T cells was observed with surface expression of activating CD94dimNKG2C dimers appearing before inhibitory CD94brightNKG2A ones. After the acute phase of infection, the balance between inhibitory and activating receptors did not change. Thus, CMV infection induces a rapid and lasting change in the expression of NK receptors on human CD8+ T cells. Keywords: primary cytomegalovirus infection, human, CD8+ T cells, NKR, latent infection, chronic infection CMV-specific CD8+ T cells were isolated at three different stages (peak, 1 year p.i, latent) from three CMV seropositive individuals. Total RNA for each stage was pooled and compared with pooled RNA of naive CD8+ T-cells from healthy controls. For quality control naive CD8+ T-cells were compared with naive CD8+ T-cells. The experiment was performed in dye-swap.