TCR signal strength controls thymic differentiation of discrete proinflammatory γδT cell subsetsistinct TCR signal strength requirements in the thymus
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ABSTRACT: The murine thymus produces discrete γδ T cell subsets making either IFN-γ or IL-17, but the role of the TCR in this developmental process remains controversial. Here we generated a non-transgenic and polyclonal model of reduced TCR expression and signal strength selectively on γδ T cells. Mice haploinsufficient for both CD3γ and CD3δ (CD3DH) showed normal αβ thymocyte subsets but specific defects in γδ T cell development, namely impaired differentiation of IL-17-producing embryonic Vγ6+ (but not adult Vγ4+) γδ T cells and a marked depletion of IFN-γ-producing CD122+ NK1.1+ (Vγ1-biased) γδ T cells throughout life. As result, adult CD3DH mice showed defective peripheral IFN-γ responses and were resistant to experimental cerebral malaria. Thus, strong TCR signaling is required within specific developmental windows with distinct Vγ usage and differential cytokine production by effector γδ T cell subsets. We investigated the transcriptional changes associated with reduced TCRγδ signaling in the CD3DH model. Transcriptome-wide analysis of FACS-purified CD3DH or WT γδ thymocytes from E18 or 6-week was carried looking for patterns of gene expression during ontogeny
Project description:The murine thymus produces discrete γδ T cell subsets making either IFN-γ or IL-17, but the role of the TCR in this developmental process remains controversial. Here we generated a non-transgenic and polyclonal model of reduced TCR expression and signal strength selectively on γδ T cells. Mice haploinsufficient for both CD3γ and CD3δ (CD3DH) showed normal αβ thymocyte subsets but specific defects in γδ T cell development, namely impaired differentiation of IL-17-producing embryonic Vγ6+ (but not adult Vγ4+) γδ T cells and a marked depletion of IFN-γ-producing CD122+ NK1.1+ (Vγ1-biased) γδ T cells throughout life. As result, adult CD3DH mice showed defective peripheral IFN-γ responses and were resistant to experimental cerebral malaria. Thus, strong TCR signaling is required within specific developmental windows with distinct Vγ usage and differential cytokine production by effector γδ T cell subsets.
Project description:Glioblastoma multiforme (GBM) is clinically highly aggressive as a result of evolutionary dynamics induced by cross-talk between cancer cells and a heterogeneous group of immune cells in tumor microenvironment. The brain harbors limited numbers of immune cells with few lymphocytes and macrophages; thus, innateâ€like lymphocytes, such as γδ T cells, have important roles in antitumor immunity. Here, we characterized GBMâ€infiltrating γδ T cells, which may have roles in regulating the GBM tumor microenvironment and cancer cell gene expression. V(D)J repertoires of tumorâ€infiltrating and bloodâ€circulating γδ T cells from four patients were analyzed by next-generation sequencing-based T-cell receptor (TCR) sequencing in addition to mutation and immune profiles in four GBM cases. In all tumor tissues, abundant innate and effector/memory lymphocytes were detected, accompanied by large numbers of tumorâ€associated macrophages and closely located tumorâ€infiltrating γδ T cells, which appear to have anti-tumor activity. The immune-related gene expression analysis using the TCGA database showed that the signature gene expression extent of γδ T cells were more associated with those of cytotoxic T and Th1 cells and M1 macrophages than those of Th2 cells and M2 macrophages. Although the most abundant γδ T cells were Vγ9Vδ2 T cells in both tumor tissues and blood, the repertoire of intratumoral Vγ9Vδ2 T cells was distinct from that of peripheral blood Vγ9Vδ2 T cells and was dominated by Vγ9Jγ2 sequences, not by canonical Vγ9JγP sequences that are mostly commonly found in blood γδ T cells. Collectively, unique GBMâ€specific TCR clonotypes were identified by comparing TCR repertoires of peripheral blood and intraâ€tumoral γδ T cells. These findings will be helpful for the elucidation of tumor-specific antigens and development of anticancer immunotherapies using tumor-infiltrating γδ T cells.
Project description:Coupling immunity and development is essential to ensure survival despite changing internal conditions in the organism. The metamorphosis of the fruit fly represents a striking example of drastic and systemic physiological changes that need to be integrated with the innate immune system. However, the mechanisms that coordinate development and immune cell activity in the transition from larva to adult in Drosophila remain to elucidate. The steroid hormone ecdysone is known to act as a key coordinator of metamorphosis. This hormone activates a nuclear receptor, the Ecdysone Receptor (EcR), which acts as a heterodimer with its partner Ultraspiracle (USP). Together, they activate the transcription of primary response genes, which in turn activate the transcription of a battery of late response genes. We have revealed that regulation of macrophage-like cells (hemocytes) by the steroid hormone ecdysone is essential for an effective innate immune response over metamorphosis. We have shown that in response to ecdysone signalling, hemocytes rapidly up regulate actin dynamics, motility and phagocytosis of apoptotic corpses, and acquire the ability to chemotax to damaged epithelia. Most importantly, individuals lacking ecdysone-activated hemocytes are defective in bacterial phagocytosis and are fatally susceptible to infection by bacteria ingested at larval stages, despite the normal systemic production of antimicrobial peptides. This decrease in survival is comparable to the one observed in pupae lacking immune cells altogether, indicating that ecdysone-regulation is essential to hemocyte immune functions and survival after infection. To better understand the ecdysone regulation of hemocyte activities, we have performed gene expression analysis. In order to identify the genes which expression change at the onset of metamorphosis, we have sorted hemocytes from 3rd instar larvae and from young prepupae and compared their gene expression. Moreover, and in order to identify which genes are regulated by the ecdysone signalling, we have used individuals expressing a dominant negative form of the Ecdysone Receptor specifically in their hemocytes. We have sorted hemocytes from 3rd instar and young prepupae of this genotype to compare their gene expression to the gene expression in larvae and prepupae from the control individuals. Hemocytes were isolated by FACS from selected 3rd instar larvae (at the late feeding stage) and prepupae (from 1h to 2h after puparium formation - APF) corresponding to two different genotypes: individuals w;HmlDeltaGal4, UAS-GFP/+ that express GFP specifically in hemocytes (genotype control), and individuals w;HmlDeltaGal4; UAS-GFP/UAS-EcRB1DN W650A which hemocytes express an Ecdysone Receptor Dominant Negative construct in addition to the GFP (EcRDN). For each of the four conditions we performed three biological replicates.
Project description:The biological effects of TTR proteins in the vasculature remain unknown. We used microarrays to detail the modulation of gene expression on HUVECs by V30M TTR when compared to cells exposed to WT TTR. HUVECs (passage 7) were cultured in the presence of WT or V30M TTR at 4M-BM-5M for 3 hours. RNA was extracted and hybridized on Affymetrix microarrays. We sought to obtain differentially expressed genes modulated by V30M TTR protein.
Project description:The approval of genetically modified (GM) crops is preceded by years of intensive research to demonstrate safety to humans and environment. We recently showed that in vitro culture stress is the major factor influencing proteomic differences of GM vs. non-GM plants. This made us question the number of generations needed to erase such memory. We also wondered about the relevance of alterations promoted by transgenesis as compared to environment-induced ones. Here we followed three rice lines (1-control- C, 1-transgenic- Ta and 1-negative segregant- NSb) throughout eight generations after transgenesis, and further analyzed their response to salinity stress on the F6 generation. Three pools of 10 whole fifteen days-old rice seedlings (Oryza sativa L. ssp. japonica cv. Nipponbare) were selected from each line at F4, F6 and F8 generations. Because salinity stress was imposed on half of the seedlings (C, Ta and NSb) in F6 generation, from this generation onwards we worked with six rice lines (C, Csalt, Ta, Tasalt, NSb, NSbsalt).
Project description:The SnRK1 protein kinase, the plant ortholog of mammalian AMPK and yeast Snf1, is activated by the energy depletion caused by adverse environmental conditions. Upon activation, SnRK1 triggers extensive transcriptional changes to restore homeostasis and promote stress tolerance and survival partly through the inhibition of anabolism and the activation of catabolism. Despite the identification of a few bZIP transcription factors as downstream effectors, the mechanisms underlying gene regulation, and in particular gene repression by SnRK1, remain mostly unknown. microRNAs (miRNAs) are 20-24nt RNAs that regulate gene expression post-transcriptionally by driving the cleavage and/or translation attenuation of complementary mRNA targets. In addition to the well-established role of miRNAs as regulators of plant development, mounting evidence implicates miRNAs in the response to environmental stress. Given the involvement of miRNAs in stress responses and the fact that some of the SnRK1-regulated genes are miRNA targets, we postulated that miRNAs drive part of the transcriptional reprogramming triggered by SnRK1 activation. To test this we have performed comparative analyses of the transcriptional response to energy deprivation between WT and dcl1-9, a mutant deficient in miRNA biogenesis. To assess the impact of miRNA deficiency on the starvation response we performed transcriptomics analyses of WT and dcl1-9 plants by subjecting leaves to 6h of light (control) or darkness (starvation)
Project description:mRNA profiles generated from primary fibroblast upon treatment with miR-211, miR-302 or melanoma melanosomes. Abstract: Melanoma originates in the epidermis and enters the metastatic and lethal phase upon invasion into the dermis. However, the interactions between melanoma cells and the dermis prior to this invasion have been poorly studied. Here we uncover that melanoma cells directly affect the formation of the dermal tumor niche by microRNA (miRNA) trafficking prior to invading the dermis. Melanocytes, the cells of melanoma origin, are specialized in trafficking of pigment vesicles, termed melanosomes and, interestingly, melanoma cells retain this trafficking ability. In melanoma in-situ specimens, we found melanosome markers in distal fibroblasts prior to the invasion of melanoma cells into the dermis. Melanoma-derived melanosomes carry miRNAs into primary fibroblasts that trigger changes in the fibroblasts, including increased proliferation, migration, and expression of pro-inflammatory genes, all known features of cancer-associated fibroblasts (CAFs). Specifically, we found that melanosomal miRNA-211 directly targets IGF2R and leads to MAPK signaling activation in fibroblasts, which reciprocally encourages melanoma growth. Treatment of melanoma cells with a melanosome release-inhibitor prevented CAF formation. Since the first interaction of melanoma cells with blood vessels occurs in the dermis, our data suggest a promising opportunity to block melanoma cell invasion by preventing the formation of the dermal tumor niche. In the paper we showed the 10% of most differentially expressed mRNA upon miR-211, miR-320c and melanosomes treatment and overlap of 2000 downregulated mRNA upon miR-211 and melanosomes treatment with predicted target gene miR-211 and CAFs related genes Expresssion profiling was performed for primary fibroblasts transfected with miRNA-211 mimic and miRNA-320c mimic.
Project description:Attempts to establish a tissue bank from autopsy samples have led to uncovering of the secrets of many diseases. Here, we examined the length of time that the RNA from postmortem tissues is available for microarray analysis and reported the gene expression profile for up- and down-regulated genes during the postmortem interval (PMI). We extracted RNA from fresh-frozen (FF) and formalin-fixed paraffin-embedded (FFPE) brains and livers of three different groups of mice: 1) mice immediately after death, 2) mice that were stored at room temperature for 3 h after death, and 3) mice that were stored at 4°C for 18 h after death, as this storage resembles the human autopsy process in Japan. Based on the microarray analysis, we selected genes that were altered by >1.3-fold or <0.77-fold and classified these genes using hierarchical cluster analysis following DAVID (database for annotation, visualization, and integrated discovery) gene ontology analysis. These studies revealed that cytoskeleton-related genes were enriched in the set of up-regulated genes, while serine protease inhibitors were enriched in the set of down-regulated genes. Interestingly, although the RNA quality was maintained, up-regulated genes were not validated by quantitative PCR, suggesting that these genes may become fragmented or modified by an unknown mechanism. We extracted RNA from fresh-frozen (FF) brains and livers from mice under three different conditions: 1) mice just after death as a control, 2) mice that were stored at room temperature for 3 h after death, and 3) mice that were stored at 4°C for 18 h after death to resemble the human autopsy process. We also created formalin-fixed paraffin-embedded (FFPE) tissue blocks at the same time using mouse organs obtained under the three conditions described above. We then purified RNA from the FFPE tissue blocks. Furthermore, we performed microarray analysis to examine changes in the gene expression profiles during the postmortem interval in FF samples and to compare ene expression profiles between FF and FFPE samples at three different postmortem times as described for the FF samples.
Project description:Several recombinat viruses of porcine circovirus type 2 (PCV2),including P1, P2, ZJ-R, VL258, and VL264, have been found. The PK15 cells were transfected by the molecular clones of the abovementioned viruses, where specific sets of genes are up-regulated or down-regulated. We used microarrays to detail the global programme of gene expression and identified distinct functions of viruses or viral proteins. PK15 cells were selected at 12 hours post-transfection for RNA extraction and hybridization on Affymetrix microarrays. We sought to obtain the gene expression patterns of PK15 cells transfected with different molecular clones of the viruses.
Project description:Phenotypic variability in cultured mammalian cell lines has long been recognized and known to be driven by passaging and culture conditions. Yet, the effect these variations have on the production of gene therapy viral vectors has been largely overlooked. In this work we evaluated the impact of using MDCK parental cells from ATCC or ECACC for the production of canine adenoviral vectors type 2 (CAV-2) in adherent and suspension cultures. Additionally, we conducted whole-genome transcriptome analysis to further explore the differences between cells. Our results indicate that ECACC parental cells are a less heterogeneous population, relatively to ATCC’s, more difficult to adapt to suspension and serum-free culture conditions, but more permissive to CAV-2 replication progression enabling higher yields. Transcriptome data indicates that this increased permissiveness is due to a general down-regulation of biological networks of innate immunity in ECACC cells.