Project description:Inducible nitric oxide synthase (iNOS) plays a crucial role in controlling growth of mycobacteria, presumed to be via nitric oxide (NO) mediated killing. However, NOS enzymes can also signal through NO-independent pathways, and production of NO by NOS requires the cofactor tetrahydrobiopterin (BH4). We compared Nos2-/- mice to mice with macrophage BH4 deficiency (Gch1fl/flTie2cre), due to a leukocyte-specific deletion of Gch1, to uncover the specific contribution of NO-independent NOS functions to anti-mycobacterial immunity. We used microarrays to detail the global programme of gene expression in uninfected and BCG infected macrophages that were either deficient in iNOS (Nos2-/- vs C57bl6/J) or BH4/Gch1 (GCHfl/flTie2cre vs GCHfl/fl)
Project description:Analysis of the effects of targeting NOS2 at the gene expression level. Our studies demonstrated a role for NOS2 in glioma biology through the maintenance of the glioma stem cell phenotype. Microarray results provide novel targets of NOS2 and suggest mechanisms through which NOS2 contributes to glioma stem cell biology. Glioma stem cells isolated from two different human glioma xenografts were infected with a non-targeting control shRNA or two different shRNAs directed against NOS2 (each treatment in each tumor performed in technical duplicates).
Project description:New strategies are required to reduce the worldwide burden of tuberculosis. Intracellular survival and replication of Mycobacterium tuberculosis after macrophage phagocytosis is a fundamental step in the complex host-pathogen interactions that lead to granuloma formation and disease. Greater understanding of how the bacterium survives and thrives in these environments will inform novel drug and vaccine discovery programmes. Here, we use in-depth RNA sequencing of Mycobacterium bovis BCG from human THP-1 macrophages to describe the mycobacterial adaptations to the intracellular environment. We identify 329 significantly differentially regulated genes, highlighting cholesterol catabolism, methyl-citrate cycle and iron homeostasis as important for mycobacteria inside macrophages. Focused analysis of PE/PPE and cytochrome P450 gene families highlight additional pathways that are upregulated (35 and five respectively) 24h after infection. Comparison of the intracellular transcriptome to gene essentiality and immunogenicity studies identified 15 potential targets that are both required for intracellular survival and induced on infection, and eight genes upregulated that have been demonstrated to be immunogenic in TB patients. Further insight into these new and established targets will support drug and vaccine development efforts.
Project description:Analysis of the effects of targeting NOS2 at the gene expression level. Our studies demonstrated a role for NOS2 in glioma biology through the maintenance of the glioma stem cell phenotype. Microarray results provide novel targets of NOS2 and suggest mechanisms through which NOS2 contributes to glioma stem cell biology.
Project description:Radiation and BCG instillations are used clinically for treatment of urothelial carcinoma, but the precise mechanisms by which they activate an immune response remain elusive. The role of the cGAS-STING pathway has been implicated in both BCG and radiation-induced immune response however comparison of STING-pathway molecules and immune landscape following treatment in urothelial carcinoma has not be performed. We therefore comprehensively analyzed the local immune response in the bladder tumor microenvironment following radiotherapy and BCG instillations in a well-established spontaneous murine model of urothelial carcinoma to provide insight into activation of STING-mediated immune response. Mice were exposed to the oral carcinogen, BBN, for 12 weeks prior to treatment with a single 15Gy dose of radiation or 3 intravesical instillations of BCG (1x108 CFU). At sacrifice, tumors were staged by a urologic pathologist and effects of therapy on the immune microenvironment were measured using NanoString Myeloid Innate Immunity Panel and immunohistochemistry. Clinical relevance was established by measuring immune biomarker expression of cGAS and STING on a human tissue microarray consisting of BCG-treated non-muscle invasive urothelial carcinomas. BCG instillations in the murine model elevated STING and downstream STING-induced interferon and pro-inflammatory molecules, intratumoral M1 macrophage and T-cell accumulation, and complete tumor eradication. In contrast, radiotherapy caused no changes in STING pathway or innate immune gene expression; rather, it induced M2 macrophage accumulation and elevated FoxP3 expression characteristic of immunosuppression. In human non-muscle invasive bladder cancer, STING protein expression was elevated at baseline in patients who responded to BCG therapy and increased further after BCG therapy. Overall, these results show that STING pathway activation plays a key role in effective BCG-induced immune response and strongly indicate that the effects of BCG on the bladder cancer immune microenvironment are more beneficial than those induced by radiation.
Project description:This SuperSeries is composed of the following subset Series: GSE29192: Implication of Nos2 inactivation on the transcriptome of developing cerebellum and Ptch1+/- medulloblastomas (mRNA) GSE29199: Implication of Nos2 inactivation on genomic changes in Ptch1+/- medulloblastomas (array-CGH) Refer to individual Series