Project description:The co-infection of hepatitis B (HBV) patients with the hepatitis D virus (HDV) causes the most severe form of viral hepatitis and thus drastically worsens the course of the disease. Therapy options for HBV/HDV patients are still limited. Here, we investigated the potential of natural killer (NK) cells that are crucial drivers of the innate immune response against viruses to target HDV-infected hepatocytes. We established in vitro co-culture models using HDV-infected hepatoma cell lines and human peripheral blood NK cells. We determined NK cell activation by flow cytometry, transcriptome analysis, bead-based cytokine immunoassays, and NK cell-mediated effects on T cells by flow cytometry. We validated the mechanisms using CRISPR/Cas9-mediated gene deletions. Moreover, we assessed the frequencies and phenotype of NK cells in peripheral blood of HBV and HDV superinfected patients. Upon co-culture with HDV-infected hepatic cell lines, NK cells upregulated activation markers, interferon-stimulated genes (ISGs) including the death receptor ligand tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), produced interferon (IFN)-gamma and eliminated HDV-infected cells via the TRAIL-TRAIL-R2 axis. We identified IFN-beta released by HDV-infected cells as an important enhancer of NK cell activity. In line with our in vitro data, we observed activation of peripheral blood NK cells from HBV/HDV co-infected, but not HBV mono-infected patients. Our data demonstrate NK cell activation in HDV infection and their potential to eliminate HDV-infected hepatoma cells via the TRAIL/TRAIL-R2 axis which implies a high relevance of NK cells for the design of novel anti-viral therapies.
Project description:Investigation of the change of the Trail-dependent NK cell transcriptome during short-term (24h) infection with lymphocytic choriomeningitis virus (LCMV). RNA sequencing-based transcriptomics analysis was performed in spleen-isolated (NK1.1+CD3-) NK cells from 3 naïve Trail+/+ mice, 3 naive Trail-/- mice, 4 LCMV-infected Trail+/+ mice, and 4 LCMV-infected Trail-/- mice.
Project description:The anti-leukemia activity of NK cells helps to prevent relapse during hematopoietic stem cell transplantation in leukemia patients. However, the factors that determine sensitivity or resistance of leukemia cells in the context of NK-mediated cytotoxicity are not well established. Here we performed a genome-wide CRIPSR screen in the human chronic-myelogenous-leukemia (CML) cell line K562 to identify genes that regulate vulnerability of leukemia cells to killing by primary human NK cells. Distribution of guide RNAs (gRNAs) in K562 cells that survived co-incubation with NK cells showed that loss of NCR3LG1, which encodes the ligand of the natural cytotoxicity receptor NKp30, protected K562 cells from killing. In contrast, loss of genes that regulate pathways for antigen-presentation and interferon-gamma-signaling increased the vulnerability of K562 cells. Addition of IFN-gamma neutralizing antibody increased the susceptibility of K562 cells to NK-mediated killing. Upregulation of MHC class I on K562 cells after co-incubation with NK cells was dependent on IFNGR2. Analysis of RNA-seq data from The Cancer Genome Atlas (TCGA) showed that low IFNGR2 expression in cancer tissues associated with improved overall survival in acute myeloid leukemia (AML) and Kidney Renal Clear Cell Carcinoma (KIRC) patients. Our results showing that upregulation of MHC class I by NK-derived IFN-gamma leads to resistance to NK cytotoxicity suggest that targeting IFN-gamma responses might be a promising approach to enhance NK cell anti-cancer efficacy.
Project description:Transcriptional activation of cultured mouse astrocytes in response to stimulation with CCM (complete cytokine mix: TNF-alpha, IL1-beta and IFN-gamma) at 4hr and 16hr time points.
Project description:Astrocytes are considered as an important contributor of the central nervous system (CNS) disorders, and particularly multiple sclerosis. Transcriptome of these cells is greatly affected by cytokines released by lymphocytes penetrating the blood-brain barrier, particularly classical pro-inflammatory cytokine interferon-gamma (IFN-gamma). We report here transcriptomal profiling of astrocytes treated by IFN-gamma and perspective remyelinization agent benztropine. Our findings indicate that expression of genes involved in antigen processing and presentation in astrocytes are significantly upregulated upon IFN-gamma exposure emphasizing critical role of this cytokine in redirecting of immune response towards self-antigens. Data reported herein support previous observations that IFN-gamma-induced JAK-STAT signaling pathway may be regarded as valuable target for the pharmaceutical intervention.
Project description:Natural killer (NK) cells are lymphocytes of the innate immune system that are involved in controlling tumors or microbial infections through the production of interferon gamma (IFN-γ). Granulocyte-colony stimulating factor (G-CSF) inhibits IFN-γ secretion by NK cells, but the mechanism underlying this effect remains unclear. Here, by comparing the multi-omics profiles of human NK cells before and after in vivo G-CSF treatment, we identified a pathway that was activated in response to G-CSF treatment, which suppressed IFN-γ secretion in NK cells. Specifically, our integrative genomic strategy revealed glucocorticoid receptor (GR) activation in NK cells that mediated the genomic response to G-CSF treatment. Activated GRs can inhibit secretion of IFN-γ by promoting interactions between suppressor of cytokine signaling 1 (SOCS1) promoter and enhancer, as well as increase the expression of SOCS1. Experiments in mice confirmed that G-CSF in vivo treatment significantly down-regulated IFN-γ secretion and up-regulated GR and SOCS1 expression in NK cells. In addition, GR blockade (RU486) significantly reversed the effects of G-CSF, demonstrating that GR up-regulates SOCS1 and inhibits the production of IFN-γ by NK cells.
Project description:Natural killer (NK) cells are lymphocytes of the innate immune system that are involved in controlling tumors or microbial infections through the production of interferon gamma (IFN-γ). Granulocyte-colony stimulating factor (G-CSF) inhibits IFN-γ secretion by NK cells, but the mechanism underlying this effect remains unclear. Here, by comparing the multi-omics profiles of human NK cells before and after in vivo G-CSF treatment, we identified a pathway that was activated in response to G-CSF treatment, which suppressed IFN-γ secretion in NK cells. Specifically, our integrative genomic strategy revealed glucocorticoid receptor (GR) activation in NK cells that mediated the genomic response to G-CSF treatment. Activated GRs can inhibit secretion of IFN-γ by promoting interactions between suppressor of cytokine signaling 1 (SOCS1) promoter and enhancer, as well as increase the expression of SOCS1. Experiments in mice confirmed that G-CSF in vivo treatment significantly down-regulated IFN-γ secretion and up-regulated GR and SOCS1 expression in NK cells. In addition, GR blockade (RU486) significantly reversed the effects of G-CSF, demonstrating that GR up-regulates SOCS1 and inhibits the production of IFN-γ by NK cells.
Project description:Natural killer (NK) cells are lymphocytes of the innate immune system that are involved in controlling tumors or microbial infections through the production of interferon gamma (IFN-γ). Granulocyte-colony stimulating factor (G-CSF) inhibits IFN-γ secretion by NK cells, but the mechanism underlying this effect remains unclear. Here, by comparing the multi-omics profiles of human NK cells before and after in vivo G-CSF treatment, we identified a pathway that was activated in response to G-CSF treatment, which suppressed IFN-γ secretion in NK cells. Specifically, our integrative genomic strategy revealed glucocorticoid receptor (GR) activation in NK cells that mediated the genomic response to G-CSF treatment. Activated GRs can inhibit secretion of IFN-γ by promoting interactions between suppressor of cytokine signaling 1 (SOCS1) promoter and enhancer, as well as increase the expression of SOCS1. Experiments in mice confirmed that G-CSF in vivo treatment significantly down-regulated IFN-γ secretion and up-regulated GR and SOCS1 expression in NK cells. In addition, GR blockade (RU486) significantly reversed the effects of G-CSF, demonstrating that GR up-regulates SOCS1 and inhibits the production of IFN-γ by NK cells.
Project description:Natural killer (NK) cells are lymphocytes of the innate immune system that are involved in controlling tumors or microbial infections through the production of interferon gamma (IFN-γ). Granulocyte-colony stimulating factor (G-CSF) inhibits IFN-γ secretion by NK cells, but the mechanism underlying this effect remains unclear. Here, by comparing the multi-omics profiles of human NK cells before and after in vivo G-CSF treatment, we identified a pathway that was activated in response to G-CSF treatment, which suppressed IFN-γ secretion in NK cells. Specifically, our integrative genomic strategy revealed glucocorticoid receptor (GR) activation in NK cells that mediated the genomic response to G-CSF treatment. Activated GRs can inhibit secretion of IFN-γ by promoting interactions between suppressor of cytokine signaling 1 (SOCS1) promoter and enhancer, as well as increase the expression of SOCS1. Experiments in mice confirmed that G-CSF in vivo treatment significantly down-regulated IFN-γ secretion and up-regulated GR and SOCS1 expression in NK cells. In addition, GR blockade (RU486) significantly reversed the effects of G-CSF, demonstrating that GR up-regulates SOCS1 and inhibits the production of IFN-γ by NK cells.