Project description:Poor immune reconstitution following haematopoietic stem cell transplantation (HSCT) can cause unwanted and harmful sequelae in recipients with chronic cytomegalovirus (CMV) infection. To understand the molecular mechanisms underlying poor reconstitution, we profiled the transcriptome-chromatin accessibility landscape of CMV-specific CD8+ memory lymphocytes from HCST recipients with different reconstitution efficiencies. Although the transcriptional and epigenomic signatures in non-reactive lymphocytes were not naïve or classic ‘exhaustion’ profiles, some gene expression was common to lymphocytes from other non-resolving infections. Reactive lymphocytes expressed higher levels of interferon/defence response and cell cycle genes in an interconnected network involving PI3KCG, STAT5B, NFAT, RBPJ, and NR3C1, increasing chromatin accessibility at the enhancer regions of immune and T cell receptor signalling pathway genes. We propose that increased HDAC6 expression in non-reactive lymphocytes decreases accessibility at particular enhancers including PI3KCG. Non-reactive cells also expressed higher levels of EGR and KLF factors that, along with lower expression of JARID2, maintained higher accessibility at promoter and CpG-rich regions of genes associated with apoptosis. Together, transcription factors and chromatin modulators create a different chromatin accessibility landscape in reactive and non-reactive cells that not only affects immediate gene expression but differentially primes the cells for responses to additional signals.
Project description:Circulating tumor-reactive lymphocytes (CTRL) present in blood circulation at a very low frequency. We efficiently isolated them based on high-performance microfluidics and MHC multimer binding assay. Using an ultra-low input bulk RNAseq workflow, we systematically characterize the transcriptomic profile of tumor-reactive lymphocytes and identified novel biomarkers for multimer-free isolation. Two animal models were studied - B16 melanoma model and CT-26 colon cancer model.
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:The subject of this study is the adoptive transfer of selected autologous tumor infiltrating lymphocytes (TIL) after in vitro expansion for the treatment of solid tumor malignancies. The TIL selection process is based on evidence showing that CD8+ TIL which co-express both CD39 and CD103 harbor the bulk of tumor-reactivity and that the remaining CD8 TIL is mainly composed of non-tumor reactive bystander cells. All of the expanded TIL that are produced (1-40 billion are expected) will be delivered in the form of a cell suspension to the participants by intravenous infusion. It is proposed that these selected TIL will produce a more potent and efficacious treatment of late-stage cancer.
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.
Project description:The purpose of this microarray study is to characterize molecular and functional differences between CD4+CD300a+ vs CD4+CD300a- T lymphocytes, and between CD8+CD300a+ vs CD8+CD300a- T lymphocytes, respectively.
Project description:Comparison of the transcriptome of naive (CD45RA+ CD27+) and differentiated (CD27-CD28-) CD4+ lymphocytes from newborns with congenital human cytomegalovirus infection (cord blood samples) and pregnant women diagnosed with primary CMV infection. Naive cells from HCMV uninfected newborns were used as a control.