Unravelling the sex-specific diversity and functions of adrenal gland macrophages (scRNA-Seq).

Despite the ubiquitous function of macrophages across the body, the diversity, origin, and function of adrenal gland macrophages remain largely unknown. We defined the heterogeneity of adrenal gland immune cells using single-cell RNA sequencing and used genetic models to explore the developmental mechanisms yielding to macrophage diversity. We defined populations of monocyte-derived and embryonically seeded adrenal gland macrophages and identified a female-specific subset with low MHC-II expression. In adulthood, monocyte recruitment dominated adrenal gland macrophage maintenance in female mice, while self-proliferation was more important in males. Adrenal gland macrophage sub-tissular distribution followed a sex-dimorphic pattern, with MHC-IIlow macrophages located at the border between the cortex and the medulla. Macrophage sex dimorphism depended on the presence of the cortical Xzone. Forcing X-zone maintenance in males, or its degradation in females, directly impacted the presence of MHC-IIlow macrophages. Adrenal gland macrophage depletion resulted in altered tissue homeostasis, modulated lipid- metabolism and decreased local aldosterone production during stress exposure. Overall, these data explain the heterogeneity of adrenal gland macrophages and point toward sexrestricted distribution and functions of these cells. Males and females seven week old adrenal glands of C57BL/6 J were collected and digested. Cells suspension were stained using viability dye (DAPI) and CD45 antibody and all the alive CD45 cells were analysed using SCRNA-seq.尽管巨噬细胞在机体中分布广泛且功能普遍，但肾上腺巨噬细胞的多样性、起源与功能在很大程度上仍未被阐明。我们通过单细胞RNA测序（single-cell RNA sequencing，scRNA-seq）解析了肾上腺免疫细胞的异质性，并利用遗传模型探索了驱动巨噬细胞多样性的发育机制。我们鉴定了单核细胞来源及胚胎源性的肾上腺巨噬细胞群体，并发现了一群低表达MHC-II的雌性特异性亚群。在成年小鼠中，单核细胞募集主导雌性小鼠肾上腺巨噬细胞的维持，而自我增殖在雄性小鼠中更为关键。肾上腺巨噬细胞的组织内亚分布呈现性别二态性模式：低表达MHC-II的巨噬细胞定位于皮质与髓质的交界区域。巨噬细胞的性别二态性依赖于肾上腺皮质X带（Xzone）的存在。在雄性小鼠中诱导X带维持，或在雌性小鼠中诱导X带降解，会直接影响低表达MHC-II的巨噬细胞的存在状态。清除肾上腺巨噬细胞会导致组织稳态失衡、脂质代谢紊乱，并在应激暴露时降低局部醛固酮的产生水平。综上，本研究阐明了肾上腺巨噬细胞的异质性，并揭示了这类细胞的性别限制性分布与功能特征。我们收集了7周龄C57BL/6 J小鼠的肾上腺组织并进行消化。细胞悬液使用活力染料（DAPI）及CD45抗体进行染色，随后对所有存活的CD45阳性细胞进行scRNA-seq分析。