Project description:RNA stress caused by the loss of RNaseT2, which is localized in lysosomes, leads to macrophage accumulation in the spleen and liver. However, the underlying mechanism remained unclear. Here, we demonstrated that cell proliferation in Rnaset2 -/- mice is dependent on TLR13, an RNA sensor. In both organs, TLR13 was found to induce cell proliferation and survival signals. Notably, in the liver, the most accumulated Ly6Clow macrophages were found to resemble wild-type Kupffer cells. These cells were shown to exert hepatoprotective effects through the LXR-CD5L axis.
Project description:Infantile-onset RNaseT2 deficient leukoencephalopathy is characterised by cystic brain lesions, multifocal white matter alterations, cerebral atrophy, and severe psychomotor impairment. The phenotype is indistinguishable from congenital cytomegalovirus brain infection and overlaps with typeI interferonopathies like Aicardi-Goutières syndrome, strongly suggesting a role for innate immunity in its pathophysiology. To date, pathophysiological studies have been hindered by the lack of mouse models recapitulating the neuroinflammatory encephalopathy found in patients. In this study, we generated Rnaset2-/- mice using CRISPR/Cas9-mediated genome editing. Strikingly, Rnaset2-/- mice revealed strong upregulation of interferon-stimulated genes and concurrent neuroinflammation, with infiltration of CD8+ effector memory T cells and inflammatory monocytes into the grey and white matter. Homeostatic dysfunctions in glia cells and neurons revealed by single nuclei RNA sequencing provides initial insights into the mechanism of hippocampal-accentuated brain atrophy and cognitive impairment. Thus, Rnaset2 -/- mice provide an important model, to develop therapies for inborn RNaseT2 deficiency, congenital viral brain infection and further type I interferonopathies.
Project description:RNASET2-deficient leukoencephalophathy is a severe leukodystrophy affecting children with psychomotor impairements in their forst year of life. We generated the first zebrafish model for a human leukodystrophy by targetting the ortholog rnaset2 gene using mutagenesis. This zebrafish mutant recapitulated the human clinical manisfestations and developed white matter defects detectable by MRI. Additionally, this zebrafish mutant identified this disease as a lysosomal storage disorders, with RNA accumulating in neurons. To understand how accumulation of RNA in neurons trigger white matter lesions, we undertook an unbiased approach and perfored microarray analysis. We identified differentially expressed genes in mutants and the immune system as a key pathway disregulated in the zebrafish rnaset2 mutant.
Project description:To investigate the molecular pathways underlying RNASET2-mediated tumor suppression in vivo, we investigated the gene expression profile of tumor samples obtained from control and RNASET2-silenced OVCAR3 xenografts, respectively. In order to evaluate the contribution of human cancer cells and the murine host stroma to RNASET2-mediated tumorigenesis responses, total RNA extracted from tumor xenografts derived from six independent OVCAR3 cell clones (three parental and three RNASET2-silenced clones) was fluorescently labeled and hybridized to human Agilent whole-genome microarrays.
Project description:To investigate the molecular pathways underlying RNASET2-mediated tumor suppression in vivo, we investigated the gene expression profile of tumor samples obtained from control and RNASET2-silenced OVCAR3 xenografts, respectively. In order to evaluate the contribution of human cancer cells and the murine host stroma to RNASET2-mediated tumorigenesis responses, total RNA extracted from tumor xenografts derived from six independent OVCAR3 cell clones (three parental and three RNASET2-silenced clones) was fluorescently labeled and hybridized to human Agilent whole-genome microarrays. Control and RNASET2-silenced OVCAR3 were injected subcutaneously into nude mice. After 39 days mice were sacrified, tumors were extracted and total RNA purified.
Project description:Hey3Met2 cells were stably transfected with plasmids encoding either wild-type RNASET2 or a catalytically dead form (whose cDNA has been previously mutagenized in the two CAS catalytic sites) or with the empty vector as a control. The control of ovarian tumorigenesis by RNASET2 occurs through modification of the cellular microenvironment and involvement of immunocompetent cells, thus providing evidence for specific modulations of cellular responses induced by RNASET2 that might underlay ovarian tumorigenesis. In order to get more inside on the effect of RNASET2 on the modulation of other genes, a whole genome expression has been run on Hey3Met2 cell transfected with wildtype or mutated RNASET2.
Project description:To investigate the role of Tet2 deficient immune cells in hepatic stellate cell activation, wild type or Tet2 deficient B cells, T cells, and hepatic macrophages were isolated and co-cultured with purified hepatic stellate cells. Gene expression profiling analysis of bulk hepatic stellate cell RNA was then performed.
Project description:Compared to typical endothelial cells (HUVEC) and splenic macrophages (CD14+CD45+), SLCs have phenotype closer to splenic macrophages.
Project description:Hey3Met2 cells were stably transfected with plasmids encoding either wild-type RNASET2 or a catalytically dead form (whose cDNA has been previously mutagenized in the two CAS catalytic sites) or with the empty vector as a control. The control of ovarian tumorigenesis by RNASET2 occurs through modification of the cellular microenvironment and involvement of immunocompetent cells, thus providing evidence for specific modulations of cellular responses induced by RNASET2 that might underlay ovarian tumorigenesis. In order to get more inside on the effect of RNASET2 on the modulation of other genes, a whole genome expression has been run on Hey3Met2 cell transfected with wildtype or mutated RNASET2. Hey3Met2 human ovarian cancer cells were transfected with espression vectors encoding either wild type or catalitycally dead mutant RNASET2. Clones transfected with the empty vectors were used as negative controls. Three independent clones were used for the each type of transfected plasmid.