GSE173769
Single-cell atlas reveals meningeal leukocyte heterogeneity in the developing mouse brain
The meninges are important for brain development and pathology. Using single-cell RNA-sequencing, we have generated the first comprehensive transcriptional atlas of neonatal mouse meningeal leukocytes under normal conditions and after perinatal brain injury. We identified almost all known leukocyte subtypes and found differences between neonatal and adult border-associated macrophages, thus highlighting that neonatal border-associated macrophages are functionally immature with regards to immune responses compared to their adult counterparts. We also identified novel meningeal microglia-like populations that appear to participate in white matter development. Early after hypoxic-ischemic insult, neutrophil numbers increased and they exhibited increased granulopoiesis, suggesting that the meninges are an important site of immune cell expansion with implications for the initiation of inflammatory cascades after neonatal brain injury. Our study provides a single-cell-resolution view of the importance of meningeal leukocytes at different stages of development in health and disease. DOI:10.1101/gad.348190.120 Overall design: Four total meningeal samples, divided in two groups: hypoxic-ischemic (HI) and naïve mice (controls). The samples were processed in two separate runs, each with one HI sample and one naïve sample. All samples were analyzed in terms of gene expression (GEX) and immune profiling (IP) for TCR and BCR clonality,