The brain and its borders create a highly dynamic microenvironment populated with immune cells. Yet characterization of immune cells within the naive brain compartment remains limited. In this study, we used CyTOF mass cytometry to characterize the immune populations of the naive mouse brain using 44 cell surface markers. By comparing immune cell composition and cell profiles between the brain compartment and blood, we were able to characterize previously undescribed cell subsets of CD8 T cells, B cells, NK cells and dendritic cells in the naive brain. Using flow cytometry, we show differential distributions of immune populations between meninges, choroid plexus and parenchyma. We demonstrate the phenotypic ranges of resident myeloid cells and identify CD44 as a marker for infiltrating immune populations. This study provides an approach for a system-wide view of immune populations in the brain and is expected to serve as a resource for understanding brain immunity.

中文翻译：

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大脑免疫区隔的高维，单细胞特征。

大脑及其边界创建了一个充满免疫细胞的高度动态的微环境。然而，幼稚的脑室内免疫细胞的表征仍然有限。在这项研究中，我们使用CyTOF大规模流式细胞仪使用44种细胞表面标记物来表征幼稚小鼠大脑的免疫种群。通过比较大脑小室和血液之间的免疫细胞组成和细胞谱，我们能够表征幼稚大脑中CD8 T细胞，B细胞，NK细胞和树突状细胞先前未描述的细胞亚群。使用流式细胞仪，我们显示了脑膜，脉络丛和薄壁组织之间免疫种群的差异分布。我们证明驻留髓细胞的表型范围，并确定CD44作为浸润免疫种群的标志。