Project description:Cytotoxic T Lymphocytes (CTLs) are effector CD8+T cells that eradicate infected and malignant cells from organism. We analyze the role of the transcription factor NFATc1 in activation and cytotoxicity of murine CD8+ T lymphocytes
Project description:Cytotoxic T Lymphocytes (CTLs) are effector CD8+T cells that eradicate infected and malignant cells from organism. We analyze the role of the transcription factor NFATc1 in activation and cytotoxicity of murine CD8+ T lymphocytes
Project description:A plethora of data supports a major role of CD4+ and CD8+ T lymphocytes for the initiation, progression and maintenance of allergic contact dermatitis (ACD). However, in-depth understanding of the underlying molecular mechanisms is still limited. NFATc1 , a central component of the Ca++-Calcineurin-NFAT-signalling network, plays an essential role in T cell activation. We therefore investigated its impact on contact hypersensitivity (CHS), the mouse model for ACD. The CHS response to 2,4,6-trinitrochlorobenzene (TNCB) was diminished in Nfatc1fl/flxCd4-cre mice (Nfatc1-/-) as compared to wild-type (WT) animals and associated with a lower percentage of interleukin (IL)17-producing CD8+T (Tc17) cells in both inflamed skin and draining lymph nodes (dLN). In vitro Tc17 polarization assays revealed that Nfatc1-/- CD8+ T cells have a reduced capacity to polarize into Tc17 cells. Applying single-cell RNA sequencing, we realized that NFATc1 controls the T cell differentiation fate. In the absence of NFATc1, CD8+ T cells favour the development of Interferon (IFN)-g-secreting CD8+ T (Tc1) lymphocytes while in its presence they turn into Tc17 cells. Finally, we showed the adoptive transfer of TNCB-sensitized WT CD8+T cells rescued tThe CHS response could be rescued in naïve Nfatc1-/-mice by adoptive transfer of TNCB-sensitized WT CD8+T cells. Our data demonstrate that NFATc1 acts as a molecular switch controllcontrolsing the development of Tc17 cells and can be used as a target to alleviate surveilling CD8+T cell-mediated CHS responses.
Project description:In thymus hematopoietic precursor cells differentiate into αβ T cells, γδ T cells, mucosa-associated invariant T cells (MAIT), and natural killer T (NKT) cells. We show that both ablation of NFATc1 or its induction during the DN stages of thymocyte development leads to an almost normal thymocyte development but a marked increase in γδ T cells. The γδ cells deficient for NFATc1 acquire an NKT γδ cell phenotype that exhibits the expression of CD4 co-receptor, the NK1.1 marker, the augmented usage of the Vγ1.1 and Vδ6.3 segments, and an increased in IL4 and IFN-γ production.
Project description:In lymphocytes, NFATc1 is the most prominent NFAT transcription factor which play a crucial role in the fate and activity of peripheral T and B cells. NFATc1 is synthesized in two prominent isoforms, the inducible short isoform NFATc1/aA and the constitutively expressed long isoform NFATc1/C. Several lines of evidence suggested that both isoforms differ markedly in their function. It was speculated that NFATc1/aA supports the proliferation and survival of lymphocytes, whereas NFATc1/C should support apoptosis and anergy induction. To proof this hypothesis we established WEHI 231 B lymphoma cells that stably (over-) express either NFATc1/aA or NFATc1/C. In preliminary experiments we could should that WEHI cells overexpressing NFATc1/aA were protected against apoptosis induction, while cells overexpressing NFATc1/C should a higher apoptosis rate. Transcriptom analysis of WEHI-231 cells overexpressing either NFATc1/aA or NFATc1/C were performed, along with a control group of WEHI-231 cells overexpressing the E.coli enzyme BirA Ligase (which is also present in all target cell lines since for further molecular assays the NFATc1 proteins were expressed as chimeric protein containing C-terminal bio-tags. The experimental results obtained indicate that the both NFATc1 proteins, NFATc1/aA and NFATc1/C, differ tremendously in their transcriptional properties.
Project description:In thymus hematopoietic precursor cells differentiate into αβ T cells, γδ T cells, mucosa-associated invariant T cells (MAIT), and natural killer T (NKT) cells. We show that both ablation of NFATc1 or its induction during the DN stages of thymocyte development leads to an almost normal thymocyte development but a marked increase in γδ T cells. The γδ cells deficient for NFATc1 acquire an NKT γδ cell phenotype that exhibits the expression of CD4 co-receptor, the NK1.1 marker, the augmented usage of the Vγ1.1 and Vδ6.3 segments, and an increased in IL4 and IFN-γ production.
Project description:In thymus hematopoietic precursor cells differentiate into αβ T cells, γδ T cells, mucosa-associated invariant T cells (MAIT), and natural killer T (NKT) cells. We show that both ablation of NFATc1 or its induction during the DN stages of thymocyte development leads to an almost normal thymocyte development but a marked increase in γδ T cells. The γδ cells deficient for NFATc1 acquire an NKT γδ cell phenotype that exhibits the expression of CD4 co-receptor, the NK1.1 marker, the augmented usage of the Vγ1.1 and Vδ6.3 segments, and an increased in IL4 and IFN-γ production.
Project description:We performed the newly mapping of genome-wide NFATc1 binding events in VEGF-stimulated primary cultured endothelial cells, by chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq). Combined NFATc1 ChIP-seq profile and the epigenetic histone marks revealed that predominant NFATc1-occupied peaks were overlapped with promoter marking but not silencer marking. DNA microarrays with NFATc1 expression or knockdown indicated the predominant NFATc1 binding targets were correlated with induced patterns. To determine NFATc1-regulated genes, a total of 5 samples were derived from human umbilical vein endothelial cells (HUVECs) stimulated with or without 50ng/mL VEGF (VEGF 60min and 0min, respectively), pretreated with cyclosporine A (VEGF 60min plus CsA) and infected with adenovirus expressing the control or constitutively active NFATc1 (Ad-control and Ad-NFATc1).
Project description:We performed the newly mapping of genome-wide NFATc1 binding events in VEGF-stimulated primary cultured endothelial cells, by chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq). Combined NFATc1 ChIP-seq profile and the epigenetic histone marks revealed that predominant NFATc1-occupied peaks were overlapped with promoter marking but not silencer marking. DNA microarrays with NFATc1 expression or knockdown indicated the predominant NFATc1 binding targets were correlated with induced patterns.