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Analysis of the host transcriptome from demyelinating spinal cord of murine coronavirus infected mice

ABSTRACT: We use transcriptome analysis to study the spinal cord transcriptome during MHV-induced demyelinating disease and find important biological pathways for demyelinating pathology. We find evidence of a Th1 cytokine response, ongoing antigen presentation and lymphocyte proliferation, lipid metabolism changes, and eicosanoid inflammation. In addition, we report several genes important for osteoclast function have augmented expression in the CNS during demyelination, suggesting a parallel between the osteoclast and microglial functions in maintaining homeostasis and the fidelity of specialized extracellular matrices in their respective compartments.

ORGANISM(S): Mus musculus

PROVIDER: GSE44333 | GEO | 2013/06/15

SECONDARY ACCESSION(S): PRJNA189553

REPOSITORIES: GEO

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Project description:Multiple Sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) characterized by demyelination and axonal loss. Demyelinating lesions are associated with infiltrating T lymphocytes, bone marrow-derived macrophages (BMDM), and activated resident microglia. Tissue damage is thought to be mediated by T cell produced cytokines and chemokines, which activate microglia and/or BMDM to both strip myelin and produce toxic factors, ultimately damaging axons and promoting disability. However, the relative contributions of BMDM and microglia to demyelinating pathology are unclear, as their identification in MS tissue is difficult due to similar morphology and indistinguishable surface markers when activated. The CD4 T cell-induced autoimmune murine model of MS, experimental autoimmune encephalitis (EAE), in which BMDM are essential for demyelination, has revealed pathogenic and repair-promoting phenotypes associated with BMDM and microglia, respectively. Using a murine model of demyelination induced by a gliatropic coronavirus, in which BMDM are redundant for demyelination, we herein characterize gene expression profiles of BMDM versus microglia associated with demyelination. While gene expression in CNS infiltrating BMDM was upregulated early following infection and subsequently sustained, microglia expressed a more dynamic gene profile with extensive mRNA upregulation coinciding with peak demyelination after viral control. This delayed microglia response comprised a highly pro-inflammatory and phagocytic profile. Furthermore, while BMDM exhibited a mixed phenotype of M1 and M2 markers, microglia repressed the vast majority of M2-markers. Overall, these data support a pro-inflammatory and pathogenic role of microglia temporally remote from viral control, whereas BMDM retained their gene expression profile independent of the changing environment. As demyelination is caused by multifactorial insults, our results highlight the plasticity of microglia in responding to distinct inflammatory settings, which may be relevant for MS pathogenesis.

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Analysis of the host transcriptome from demyelinating spinal cord of murine coronavirus infected mice

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