Project description:To investigate the development of human leptomeninges and their co-development with the brain. Nuclei were extracted from eight human fetal leptomeninges obtained from aborted embryos, ranging from PCW8 to PCW21 (post-conceptional weeks). The entire arachnoid mater, pia mater, associated blood vessels, and immune cells were included for single-nucleus RNA sequencing (snRNA-seq).
Project description:Transplantation of retinal pigment epithelial (RPE) cells holds great promise for RPE tissue repair in patients with retinal degenerative diseases, such as age-related macular The leptomeninges envelop the central nervous system (CNS) and contribute to cerebrospinal fluid (CSF) production and homeostasis. We analyzed the meninges overlying the anterior or posterior forebrain in the adult mouse by single nuclear RNA-sequencing (snucRNA-seq). This revealed regional differences in fibroblast and endothelial cell composition and gene expression. Surprisingly, these non-neuronal cells co-expressed genes implicated in neural functions. The regional differences changed with aging, from 3 to 18 months. Cytokine analysis revealed specific soluble factor production from anterior vs posterior meninges that also altered with age. Secreted factors from the leptomeninges from different regions and ages differentially impacted the survival of anterior or posterior cortical neuronal subsets, neuron morphology, and glia proliferation. These findings suggest that meningeal dysfunction in different brain regions could contribute to specific neural pathologies. The disease-associations of meningeal cell genes differentially expressed with region and age were significantly enriched for mental and substance abuse disorders.
Project description:The leptomeninges envelop the central nervous system and contribute to brain homeostasis by producing trophic factors and regulating entrance of cells, factors and agents, immune responses and cerebrospinal fluid production. We report that leptomeninges from adult mice are regionally patterned. Leptomeninges dissected from anterior or posterior aspects of the forebrain grown in hetero- or homo-typic culture with anterior and posterior cortical cells demonstrate differences in ability to support survival of neuronal subsets and proliferation of progenitors for astrocytes and oligodendrocytes. Meningeal support changes with age: co-culture with 18-month old leptomeninges reduced numbers of cortical progenitor cells and neurons but increased astrocyte expansion. Analysis of cytokine secretion and single cell RNA-sequencing revealed differences in anterior versus posterior, young versus old meningeal factors and composition. These data demonstrate that adult leptomeninges are regionally patterned in cell composition and functional properties, and suggest that meningeal deficits may contribute to brain aging and disease.
Project description:Ms4a3-Cre: R26-TdTomato: Cx3cr1-gfp mice allow discrimination between YS-derivd and monocyte-derived macrophages in the brain parenchyma and leptomeninges by color. We used single cell RNAseq for RNA profiling to compare YS-derived micrglia, monocyte-derived microglia, YS-derived leptomeningeal macrophages, and monocyte-derived leptomeningeal macrophages.