Project description:To identify the direct targets of Zeb1 we performed ChIP-seq of wild type cDC1 cell line in unstimulated condition. cDC1 cell line was used for Chromatin Immunoprecipitation, it was then fixed and crosslinked and then fragmented and the fragmented DNA-protein was immunoprecipated using Zeb1 antibody. The chromatin sample was then used to prepare library using NEB kit following the manufacturer's protocol
Project description:To have a mechanistic insight how the Zeb1 KD CD8+cDC1 perturbs the immune response globally. to identify the genes that are regulated by Zeb1 RNA was isolated and check for quality, then we used NEB RNA library preparation kit to prepare the library and send for sequencing on Illumina Hi-seq 2500 platform
Project description:RNA-seq of the immune-suppressed cDC1 was done to look into the mechanism underlying TLR9. It was then compared with the inflammatory cDC1 DCs.
Project description:The expression of the XCR1 chemokine receptor univocally identifies all type 1 conventional dendritic cells (cDC1) throughout the body. The gene encoding its ligand, XCL1, is expressed constitutively by innate lymphoid cells such as natural killer (NK) cells. The evolutionary conservation of XCR1, XCL1 in vertebrates suggests that they play a critical, yet uncharacterized, role in immune responses. Here we showed using mouse cytomegalovirus (MCMV) infection, that the XCL1/XCR1 axis promoted the intra-splenic repositioning of cDC1 towards IFN--producing NK cells forming superclusters around infected cells. There, cDC1 and NK cells engaged into physical interactions enhancing their respective production of IL-12 and IFN-. This feed-forward mechanism also led to NK cell production of GM-CSF, which upregulated CCR7 on cDC1, instructing them to migrate into the T cell area for the priming of CD8+ T cells. In conclusion, we identified a novel mechanism through which NK cells boost the relay between innate and adaptive immunities by regulating the spatiotemporal functions of cDC1.
Project description:CD4 T cells are thought to help promote anti-tumour responses by ‘licensing’ antigen presenting cells (APCs) that activate CD8 T cells. Conventional type 1 dendritic cells (cDC1s) are responsible for cross-presentation of tumour-derived antigens to CD8 T cells. Prevailing models presume that the cDC1 is licensed by CD4 T cells that are themselves activated by a distinct cDC subset, the cDC2. The recent finding that neoantigens presented by major histocompatibility complex (MHC) class II molecules can promote rejection of tumours that lack MHC class II (MHC-II) surface expression is consistent with an indirect action of CD4 T cells, such as cDC1 licensing. However, no study has directly identified the APC that primes the CD4 T cells responsible for licensing or clearly identified the target of CD4 licensing in vivo. Here, we generated cDC1-specific Cre expressing mouse strain to inactivate or induce expression of MHC-I, MHC-II, or CD40 specifically within the cDC1 lineage. Using a tumour model that relies on CD8 T cells and CD4 T cells for rejection, we discovered that early priming of CD4 T cells against tumour-derived antigens, in contrast to soluble antigens, relied overwhelmingly on the cDC1 and not the cDC2. cDC1 do not simply transport antigen to lymph nodes for processing by cDC2, since lack of MHC-II expression on cDC1 prevented CD4 T cell priming. We also found that CD40 signaling not only affects licensing of cDC1 for CD8 T cell priming, but is also critical for the activation of CD4 T cells. Thus, in the setting of tumour-derived antigens, cDC1 can function as an autonomous platform, capable of priming both CD4 and CD8 T cells and orchestrating their cross-talk required for optimal anti-tumour immunity.
Project description:The efficacy of immunotherapies in metastatic melanoma depends on a robust T cell infiltration. Consistently, defining cancer cell intrinsic mechanisms mediating T cell exclusion and immune resistance is crucial. The EMT inducing transcription factor ZEB1 is a major regulator of melanoma cell plasticity, driving resistance to MAPK targeted therapies. Here, by analyzing the immune infiltrates of a cohort of melanoma patients, we demonstrate that high ZEB1 expression in tumor cells is associated with a decrease in CD8+ T lymphocyte infiltration, independently of beta-catenin pathway activation. Moreover, gain- or loss-of-function experiments in melanoma mouse models show that ZEB1 regulates tumor growth by controlling CD8+ T cell recruitment, via its negative action on the production of T cell attracting chemokines, and that its targeting improves the efficacy of anti-PD1 immunotherapy. Overall, the major role of ZEB1 in preventing T cell infiltration suggests it may constitute a new target in metastatic melanoma.
Project description:Here we performed a ChIP-seq experiment on a sample of adherent cultures of mouse neural stem cells (NS5 cell line) under normal growth conditions. This resulted in the generation of a genome-wide map of Zeb1 binding to chromatin.