Human serous cavity macrophages and dendritic cells possess counterparts in the mouse with a distinct distribution between species. Human serous cavity macrophages and dendritic cells possess counterparts in the mouse with a distinct distribution between species

In mouse peritoneal and other serous cavities, the transcription factor Gata6 drives the identity of the major cavity resident population of macrophages, with a smaller subset of cavity-resident macrophages dependent on the transcription factor Irf4. Here we showed that GATA6+ macrophages in the human peritoneum were rare, regardless of age. Instead, more human peritoneal macrophages aligned with mouse CD206+ LYVE1+ cavity macrophages that represent a differentiation stage just preceding expression of Gata6. Low abundance of CD206+ macrophages was retained in C57BL/6J mice fed a high-fat diet or in wild-captured mice, suggesting that differences between serous cavity-resident macrophages in humans and mice were not environmental. Irf4-dependent mouse serous cavity macrophages aligned closely with human CD1c+CD14+CD64+ peritoneal cells that, in turn, resembled human peritoneal CD1c+CD14-CD64- cDC2. Thus, major populations of serous cavity-resident mononuclear phagocytes in humans and mice shared common features but the proportions of different macrophage differentiation stages greatly differ between the two species and DC2-like cells were especially prominent in humans. Overall design: Peritoneal wash was collected at the beginning of the procedure before it was affected by the surgical process. Patients recruited including those receiving laparoscopic surgeries including Roux-en-Y gastric bypass (RYGB) surgery, sleeve gastrectomy, gastrostomy tube placement, cholecystectomy, or inguinal hernia repair without any other clinical indication of peritoneal pathological conditions. Live CD45+ immune cells were sorted for sequencing >>>Raw data are being deposited in dbGaP due to patient privacy concerns<<<

在小鼠腹膜及其他浆膜腔中，转录因子Gata6决定了主要腔室驻留巨噬细胞群的细胞身份，而少量腔室驻留巨噬细胞亚群则依赖转录因子Irf4。
本研究发现，无论年龄如何，人类腹膜内的GATA6+巨噬细胞均极为罕见。与之相反，多数人类腹膜巨噬细胞与小鼠CD206+ LYVE1+腔室巨噬细胞表型一致，这类小鼠巨噬细胞处于Gata6表达前的分化阶段。
喂食高脂饮食的C57BL/6J小鼠以及野生捕获小鼠中，CD206+巨噬细胞仍保持低丰度，这表明人类与小鼠浆膜腔驻留巨噬细胞的差异并非由环境因素导致。
依赖Irf4的小鼠浆膜腔巨噬细胞与人类CD1c+CD14+CD64+腹膜细胞高度相似，而这类人类细胞又与人类腹膜内的CD1c+CD14-CD64- cDC2表型一致。
因此，人类与小鼠浆膜腔驻留单核吞噬细胞的主要群体具有共同特征，但两类物种间不同巨噬细胞分化阶段的占比差异显著，且DC2样细胞在人类体内尤为丰富。
实验设计：在手术流程影响腹膜灌洗液前，于操作伊始收集该样本。招募的患者涵盖接受腹腔镜手术者，具体术式包括Roux-en-Y胃旁路术（Roux-en-Y gastric bypass, RYGB）、袖状胃切除术、胃造瘘管置入术、胆囊切除术或腹股沟疝修补术，且所有患者均无其他腹膜病理状态的临床指征。分选活的CD45+免疫细胞用于测序>>>由于患者隐私问题，原始数据正提交至dbGaP数据库<<<