Project description:Numerous lymphocytes seed the body surfaces of metazoans promoting tissue protection and integrity. These tissue-resident populations differ substantially from circulating lymphocytes, as they adopt a unique phenotype and do not recirculate. They span the innate-adaptive continuum, ranging from innate lymphoid cells (ILCs) to unconventional T cells (NKT, MAIT, γδT cells and IELs) and tissue-resident memory (TRM) T cells, and while differ in the particulars of their biology, all contribute to barrier immunity, tissue homeostasis, and immune regulation. Although they share the same microenvironment, little is known about how these tissue-resident lymphocyte populations interact with each other and with the non-lymphoid cellular environment. As such, there is an emerging view of tissues as varied ‘‘ ecosystems ’’, whereby protection against inflammatory challenges is orchestrated through the interplay between tissue-resident and infiltrating-lymphocyte subtypes. In mice, barrier tissues are populated during early life by innate-like γδT lymphocytes. These cells provide tissue protection, including limiting conventional T cell-driven inflammation. Therefore, elucidating the contributions of tissue-resident T cells, particularly γδT cells, to the basic pathophysiology of tissue function and protection against infection, inflammation, and cancer is a priority. To this aim, we have induced allergic contact dermatitis in the back skin of different strains and we analyzed the behavior of γδT cells
Project description:We report the application of single cell RNA sequencing for profiling the fingerprints of γδT cells of hepatocellular carcinoma compared with healthy donors. By comparing the transcriptome and TCR clonality of γδT cells from 3 HCC patients and expanded γδT cells from 3 healthy donors, we found that expanded γδ T cells derived from different donors shared great transcriptomic similarity and we found higher enrichments of major γδ TCRs in expanded γδ T cells compared to infiltrated but not peripheral ones in HCC. Analysis of differentiation trajectory demonstrated a branched structure in expanded γδ T cells, implying functional and differentiation stage diversity, and γδ T cells from HCC patients are localized to the far end of the trajectory. Furthermore, GVSA analyses made on metabolic pathways demonstrated strong enrichments in major metabolic pathways such as OXPHOS, glycolysis, and fatty acid metabolism in expanded γδ T cells versus peripheral ones of HCC. The comparison indicated higher cytotoxicity score of expanded γδ T cells compared to infiltrated or peripheral ones of HCC. The successful application of allogeneic γδ T cells immunotherapy in late-stage liver cancer patients was supported by our current scRNA transcriptomic analyses, which suggested strong anti-tumor functional complementation by the ex-vivo expanded γδ T cells.
Project description:IL17-producing γδ T cells (γδ T17) mainly develop in the prenatal phase and persist as long-living self-renewing effector cell in all kind of tissues. They express polyclonal T-cell receptors (TCR), comprising public Vγ4+ and Vγ6+ TCRs with germline-like rearrangements. In particular, Vγ6+ T cells have recently been found in a variety of tissues including enthesis, gingiva or skin. However, their exchange between tissues and the mechanisms of tissue-specific adaptation and residency remain poorly understood. Here, we profiled Vγ6+ T cells isolated from thymus, peripheral lymph nodes (pLN) and skin through single-cell RNA-seq technology and compared those to Vγ4+ T cells. Our data demonstrated that Vγ6+ T cells formed highly homogenous cell populations that could be separated by tissue-specific gene expression signatures.
Project description:The goal of this study was to compare gene expressions on the single cell level in (i) freshly isolated PBMCs (no stimulation and no sorting), (ii) PBγδT cells; PBMCs were stimulated with HMBPP in vitro and CD3(+) γδTCR(+) cells were sorted and (iii) iγδT cells; differentiated cells from γδT-iPSC clone were stimulated with HMBPP and CD3(+) γδTCR(+) cells were sorted or not sorted.
Project description:An in-depth examination of the TCRγ locus in ILC2s and γδT cells was performed to assess the functionality of rearranged TCRγ locus.
Project description:Fresh human HCC tissue and paired pertumor liver tissue were acquired, isolation of the infiltrating lymphocytes was conducted by discontinous density gradient centrifugation in Percoll. After removal of dead cells and incubation with components of TCRγ/δ isolation kit (Mitenyi Biotec), γδ T cells were positively selected from the single-cell suspension using autoMACS Separator (Miltenyi Biotec) with recommended programs. Then we employed whole genome microarray expression profiling as a discovery platform to indentify genes which are differentially expressed between HCC-derived and paired peritumor-derived γδT cells.
Project description:The spatial organization of cells within tissues is tightly linked to their biological function. Yet, methods to probe the entire transcriptome of multiple native tissue microenvironments at single cell resolution are lacking. Here, we introduce fragment-sequencing, a method that enables the transcriptomic characterization of single cells within spatially distinct tissue niches. Fragment-sequencing of the mouse metastatic liver revealed previously uncharacterized zonated genes and ligand-receptor interactions enriched in the different hepatic microenvironments and the metastatic niche.