This SuperSeries is composed of the SubSeries listed below.
Histone Deacetylases 1 and 2 Regulate Microglia Function during Development, Homeostasis, and Neurodegeneration in a Context-Dependent Manner.
Sex, Age, Specimen part, Treatment
View SamplesHdac1 and 2 are important regulators of developmental processes. In this study we created microglia specific compound Hdac1 and Hdac2 knock out mice. Pre-natal ablation of both Hdac1 and 2 from microglia leads to reduced cell number and altered cell morphology. To investigate how Hdac1 and 2 knock out in microglia alters cellular gene expression profile we carried out RNA-seq analysis at different time points. Overall design: We used FACS sorted microglia cells from control and Hdac1/2fl/flCx3cr1Cre (constituitive knockout) or Hdac1/2fl/flCx3cr1CreERT2 (inducible) mice at different time points viz. Embryonic day 16 (E16 - inducible knockout only), Post natal day 0 (P0), 2 and 6 weeks after birth
Histone Deacetylases 1 and 2 Regulate Microglia Function during Development, Homeostasis, and Neurodegeneration in a Context-Dependent Manner.
Age, Treatment, Subject
View SamplesEpigenetic alterations has been implicated in the pathology of several neurodegenerative diseases. To investigate the role of microglial Hdac1 and 2 in the pathogenesis of Alzheimer's disease (AD), we created microglia specific compound Hdac1 and Hdac2 knock out mice in 5X FAD background. Genetic ablation of Hdac1 and 2 from microglia reduced amyloid plaque burden and improved spatial learning and memory function.
Histone Deacetylases 1 and 2 Regulate Microglia Function during Development, Homeostasis, and Neurodegeneration in a Context-Dependent Manner.
Sex, Specimen part
View SamplesWe introduce an in vivo imaging approach that allows us to temporally and spatially resolve the evolution of iNOS and Arginase-positive phagocyte phenotypes in a murine MS model. We show that the polarization of individual phagocytes is established after CNS entry, is dependent on the CNS compartment and can be adapted as inflammatory lesions move from expansion to resolution. Our study thus provides a first real-time analysis of phagocyte specification in the intact CNS. Overall design: Cells were isolated from the Blood and CNS of Arginase-YFP X iNOS-Tomato-Cre mice at clinical onset of Experimental Autoimmune Encephalomyelitis. CD11b_high, CD45_low microglia cells and CD45_positive, CD115_positive, Ly6c_high monocytes were FACS sorted respectively. Total RNA was extracted from the separated populations.
Mononuclear phagocytes locally specify and adapt their phenotype in a multiple sclerosis model.
Specimen part, Subject
View SamplesSingle cell sequencing of microglia and perivascular macrophages was performed on brain tissue from different brain regions to obtain single cell expression profiles dependent on celltype and regional location. Overall design: 425 cells from mouse (CD-1) brains at different postnatal ages as well as embryonic day E11.5-E18.5.
Spatial and temporal heterogeneity of mouse and human microglia at single-cell resolution.
Subject
View SamplesMicroglia play critical roles in neural development and homeostasis. They are also implicated in neurodegenerative and neuroinflammatory diseases of the central nervous system (CNS). However, little is known about the presence of spatially and temporally restricted subclasses of microglia during CNS development and disease. Here, we combined massively parallel single-cell analysis, single-molecule FISH, advanced immunohistochemistry and computational modelling to comprehensively characterize novel microglia subclasses, which were transcriptionally different from perivascular macrophages, in up to six different CNS regions during development and diseases. Single-cell analysis revealed specific time- and region-dependent microglia subtypes during homeostasis. In contrast, demyelinating and neurodegenerative diseases evoked context-dependent microglia subtypes with distinct molecular hallmarks and diverse cellular kinetics. Finally, diverse microglia subsets were also identified in normal and diseased human brains. Our data provide new insights into the CNS endogenous immune system during development, health and perturbations. Overall design: CD45+ cells isolated from healthy and MS-affected human brains were FACS-sorted in 384-well plates and used for scRNAseq. The patients were aged between 22 and 25 years. Data comprises 5 healthy and 5 MS patients. CEL-Seq2 protocol was used for single cell sequencing (Hashimshony et al. 2016).
Spatial and temporal heterogeneity of mouse and human microglia at single-cell resolution.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Host microbiota constantly control maturation and function of microglia in the CNS.
Specimen part, Treatment
View SamplesAs tissue macrophages of the central nervous system (CNS), microglia are critically involved in diseases of the CNS. However, it remains unknown what controls their maturation and activation under homeostatic conditions. Here we reveal significant contributions of the host microbiota to microglia homeostasis as germ-free (GF) mice displayed global defects in microglia with altered cell proportions and an immature phenotype leading to impaired innate immune responses. Temporal eradication of host microbiota severely changed microglia properties. Limited microbiota complexity also resulted in defective microglia. In contrast, recolonization with a complex microbiota partially restored microglia features. We determined that short-chain fatty acids (SCFA), microbiota-derived bacterial fermentation products, regulate microglia homeostasis. Accordingly, mice deficient for the SCFA receptor FFAR2 mirrored microglia defects found under GF conditions. These findings reveal that host bacteria vitally regulate microglia maturation and function, whereas microglia impairment can be restored to some extent by complex microbiota.
Host microbiota constantly control maturation and function of microglia in the CNS.
Specimen part, Treatment
View SamplesAs tissue macrophages of the central nervous system (CNS), microglia are critically involved in diseases of the CNS. However, it remains unknown what controls their maturation and activation under homeostatic conditions. Here we reveal significant contributions of the host microbiota to microglia homeostasis as germ-free (GF) mice displayed global defects in microglia with altered cell proportions and an immature phenotype leading to impaired innate immune responses. Temporal eradication of host microbiota severely changed microglia properties. Limited microbiota complexity also resulted in defective microglia. In contrast, recolonization with a complex microbiota partially restored microglia features. We determined that short-chain fatty acids (SCFA), microbiota-derived bacterial fermentation products, regulate microglia homeostasis. Accordingly, mice deficient for the SCFA receptor FFAR2 mirrored microglia defects found under GF conditions. These findings reveal that host bacteria vitally regulate microglia maturation and function, whereas microglia impairment can be restored to some extent by complex microbiota.
Host microbiota constantly control maturation and function of microglia in the CNS.
Specimen part, Treatment
View SamplesInnate immune memory is a vital mechanism of myeloid cell plasticity that occurs in response to environmental stimuli and alters subsequent immune responses. Two types of immunological imprinting can be distinguished—training and tolerance. These are epigenetically mediated and enhance or suppress subsequent inflammation, respectively. Whether immune memory occurs in tissue-resident macrophages in vivo and how it may affect pathology remains largely unknown. Here we demonstrate that peripherally applied inflammatory stimuli induce acute immune training and tolerance in the brain and lead to differential epigenetic reprogramming of brain-resident macrophages (microglia) that persists for at least six months. Strikingly, in a mouse model of Alzheimer's pathology, immune training exacerbates cerebral beta-amyloidosis and immune tolerance alleviates it; similarly, peripheral immune stimulation modifies pathological features after stroke. Our results identify immune memory in the brain as an important modifier of neuropathology. Overall design: mRNA was isolated from FACS-purified microglia and prepared for RNA-sequencing.
Innate immune memory in the brain shapes neurological disease hallmarks.
Sex, Specimen part, Treatment, Subject
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