Distinct Gene Profiles of Bone Marrow-Derived Macrophages and Microglia During Neurotropic Coronavirus-Induced Demyelination
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA885480 | ENA |
REPOSITORIES: ENA
Similar Datasets
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.
2022-10-02 | GSE214472 | GEO
Project description:Microglia are considered both pathogenic and protective during recovery from demyelination, but their precise role remains ill-defined. Here, using an inhibitor of colony stimulating factor 1 receptor (CSF1R), PLX5622, and mice infected with a neurotropic coronavirus (mouse hepatitis virus, strain JHMV), we show that depletion of microglia after clearance of virus infection resulted in impaired myelin repair and prolonged clinical disease. Microglia were required only during the early stages of remyelination. Notably, large deposits of extracellular vesiculated myelin and cellular debris were detected in the spinal cords of PLX5622-treated and not control mice, which correlated with decreased numbers of oligodendrocytes in demyelinating lesions in drug-treated mice. Further, gene expression analyses demonstrated differential expression of genes involved in myelin debris clearance, lipid and cholesterol recycling, and promotion of oligodendrocyte function. The results also demonstrate that microglial function could not be compensated by infiltrating macrophages. Together, these results demonstrate key roles for microglia in debris clearance and the initiation of remyelination following infection with a neurotropic coronavirus but are not necessary during later stages of remyelination.
2020-02-07 | GSE144911 | GEO
Project description:The present study examines functional contributions of microglia in host defense, demyelination, and remyelination following infection of susceptible mice with a neurotropic coronavirus. Treatment with PLX5622, an inhibitor of colony stimulating factor 1 receptor (CSF1R) that efficiently depletes microglia, prior to infection of the central nervous system (CNS) with the neurotropic JHM strain of mouse hepatitis virus (JHMV) resulted in increased mortality compared with control mice that correlated with impaired control of viral replication. Single cell RNA sequencing (scRNASeq) of CD45+ cells isolated from the CNS revealed that PLX5622 treatment resulted in muted CD4+ T cell activation profile that was associated with decreased expression of transcripts encoding MHC class II and CD86 in macrophages but not dendritic cells. Evaluation of spinal cord demyelination revealed a marked increase in white matter damage in PLX5622‐treated mice that corresponded with elevated expression of transcripts encoding disease‐associated proteins Osteopontin (Spp1), Apolipoprotein E (Apoe), and Triggering receptor expressed on myeloid cells 2 (Trem2) that were enriched within macrophages. In addition, PLX5622 treatment dampened expression of Cystatin F (Cst7), Insulin growth factor 1 (Igf1), and lipoprotein lipase (Lpl) within macrophage populations which have been implicated in promoting repair of damaged nerve tissue and this was associated with impaired remyelination. Collectively, these findings argue that microglia tailor the CNS microenvironment to enhance control of coronavirus replication as well as dampen the severity of demyelination and influence repair.
2022-10-21 | GSE215887 | GEO
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.
| S-EPMC6004766 | biostudies-literature
Project description:Triggering receptor expressed on myeloid cells 2 (TREM2) plays a protective role in neurodegenerative diseases, including Alzheimer’s and demyelinating diseases. However, Trem2 functions can exacerbate tissue damage during viral respiratory or liver infections. We therefore investigated the role of TREM2 in a viral encephalomyelitis model associated with prominent Th1 responses and demyelination. To address our hypothesis, Wild type (WT) and Trem2-/- mice were infected with a sublethal glia tropic murine coronavirus (MHV-JHM) was intracranially. Disease progression and survival were monitored daily. Immune response and demyelination in the spinal cord (SC) were determined by flow cytometry and immunofluorescences analysis. Expression of Inflammatory cytokines was measured with RT-PCR. Differential gene expression in sorted SC-derived microglia and infiltrated bone marrow-derived macrophages (BMDM) were determined by Nanostring, nCounter system, which directly captures and counts individual mRNA transcripts thereby omitting cDNA-based amplification. Upon infection, BMDM highly upregulated Trem2 mRNA compared to microglia, which showed a delayed increase coincident with demyelination. Although TREM2 deficiency did not alter disease onset and severity, it impaired clinical recovery during establishment of viral persistence associated with demyelination. Disease progression in Trem2-/- mice was not associated with altered virus control, leukocyte recruitment or overall inflammatory responses in the SC. However, there was a significant increase in degenerated myelin not associated with the myeloid markers IBA1 and/or CD68 in the lesions. Gene expression profiles of SC-derived microglia and BMDM using the Nanostring platform revealed that TREM2 deficiency resulted in the failure to upregulate genes associated with phagocytosis, including LPL and CD36. Overall our data using a virus infection model show that TREM2 deficiency does not affect viral control or T cell immunity but leads to impaired expression of select phagocytic pathway factors, ultimately resulting in failure to remove damaged myelin in demyelinated lesions. The results support that TREM2 dependent removal of damaged myelin is independent of the initial insult or the inflammatory milieu, but rather regulated by sensing a dysregulated lipid environment.
2022-11-09 | GSE206942 | GEO
Project description:Trem2 deficiency does not alter virus control but impairs phagocytic activity during neurotropic coronavirus induced demyelination
| PRJNA852802 | ENA
Project description:We examined the role of TREM2 on microglia responses to demyelination Microglia were FACS-purified from WT or Trem2-/- mice fed with 0.2% cuprizone diet.
2015-04-22 | E-GEOD-66926 | biostudies-arrayexpress
Project description:Background: Cystatin F is a secreted lysosomal cysteine protease inhibitor that has been implicated in affecting the severity of demyelination and enhancing remyelination in pre-clinical models of immune-mediated demyelination. How cystatin F impacts neurologic disease severity following viral infection of the central nervous system (CNS) has not been well characterized and was the focus of this study. We used cystatin F null-mutant mice (Cst7-/-) with a well-established model of murine coronavirus-induced neurologic disease to evaluate the contributions of cystatin F in host defense, demyelination and remyelination. Methods: Wildtype controls and Cst7-/- mice were intracranially (i.c.) infected with a sublethal dose of the neurotropic JHM strain of mouse hepatitis virus (JHMV), with disease progression and survival monitored daily. Immune cell infiltration into the brain and spinal cord was determined by flow cytometry. Spinal cord demyelination was determined by luxol fast blue (LFB) and Hematoxylin/Eosin (H&E) staining and remyelination evaluated by electron microscopy (EM) and calculation of g-ratios. Immune cell infiltration into the CNS and microglia activation were determined by flow cytometry and 10X genomics chromium 3’ single cell RNA sequencing (scRNAseq). Results: JHMV-infected Cst7-/- mice were able to control viral replication within the CNS, indicating that cystatin F is not essential for an effective Th1 anti-viral immune response. Infiltration of T cells and monocytes/macrophages into the spinal cords of JHMV-infected Cst7-/- mice was increased compared to infected controls, and this correlated with amplified demyelination and impaired remyelination. Single-cell RNA-seq of CD45+ cells enriched from spinal cords of infected Cst7-/- and control mice at day 21 post-infection (p.i.) revealed enhanced expression of transcripts encoding macrophage chemoattractant, Ccl2, and T cell chemoattractants, Cxcl9 and Cxcl10, combined with elevated expression of interferon-g (Ifng) transcripts and activation markers in CD8+ T cells from Cst7-/- mice compared to controls. Conclusions: Cystatin F is not required for immune-mediated control of JHMV replication within the CNS. However, JHMV-infected Cst7-/- mice exhibited more severe clinical disease associated with increased demyelination and impaired remyelination. The increase in disease severity was associated with elevated expression of macrophage and T cell chemoattractant chemokines, concurrent with increased neuroinflammation. These findings support the theory that one mechanism by which cystatin F affects chronic disease in mice persistently infected with JHMV is through regulating expression of pro-inflammatory molecules that impact neuroinflammation and neurologic disease.
2024-10-07 | GSE244656 | GEO
Project description:Microglia are considered both pathogenic and protective during recovery from demyelination, but their precise role remains ill defined. Here, using an inhibitor of colony stimulating factor 1 receptor (CSF1R), PLX5622, and mice infected with a neurotropic coronavirus (mouse hepatitis virus [MHV], strain JHMV), we show that depletion of microglia during the time of JHMV clearance resulted in impaired myelin repair and prolonged clinical disease without affecting the kinetics of virus clearance. Microglia were required only during the early stages of remyelination. Notably, large deposits of extracellular vesiculated myelin and cellular debris were detected in the spinal cords of PLX5622-treated and not control mice, which correlated with decreased numbers of oligodendrocytes in demyelinating lesions in drug-treated mice. Furthermore, gene expression analyses demonstrated differential expression of genes involved in myelin debris clearance, lipid and cholesterol recycling, and promotion of oligodendrocyte function. The results also demonstrate that microglial functions affected by depletion could not be compensated by infiltrating macrophages. Together, these results demonstrate that microglia play key roles in debris clearance and in the initiation of remyelination following infection with a neurotropic coronavirus but are not necessary during later stages of remyelination.
| S-EPMC7533697 | biostudies-literature
Project description:Goal: Determine the role of microglia in the antiviral response during neurotropic picornavirus infection of C57BL/6J and SJL/J mice and whether absence of microglia would affect CD4 and CD8 T cell functions. Methods: Brains from C57BL/6J and SJL/J mice treated with PLX5622 (to deplete microlgia) or control diet were harvested at 6 days post TMEV-infection. CD4+ T cells and CD8+ T cells were obtained using Easy Sep Mouse CD4+ T cell isolation Kit and Easy Sep Mouse CD8+ T cell isolation Kit (Stemcell). RNA was obtained using RNeasy (QIAGEN) and Illumina TruSeq stranded RNA Kit with Ribo-Zero Gold was then utilized to prepare cDNA library for RNA-seq. Results: Our results demonstrate strain-specific effects of the CSF1R-microglia axis in the context of neurotropic viral infection as well as inherent differences in microglial antigen presentation and subsequent T cell crosstalk that contribute to susceptibility to neurotropic picornavirus infection.
2021-05-10 | GSE160660 | GEO