西班牙国家生物技术中心 Carlos Ardavín、María López-Bravo等研究人员合作发现，常驻巨噬细胞依赖的免疫细胞支架驱动腹腔内的抗菌防御。这一研究成果于2021年10月29日在线发表在国际学术期刊《免疫》上。

研究人员利用腹腔大肠杆菌感染后的腹部败血症小鼠模型研究了控制腹腔内细菌感染的机制。腹壁和网膜的完成免疫荧光和共聚焦显微镜显示，大型腹膜巨噬细胞（LPM）迅速清除细菌并粘附在间皮上，形成由依次招募的LPM、B1细胞、中性粒细胞和单核细胞（moC）组成的多层细胞聚集。常驻巨噬细胞聚集（resMφ-aggregates）的形成需要LPM和凝血酶依赖的纤维蛋白聚合。大肠杆菌感染触发了LPM的焦亡和炎症介质的释放。

这些潜在炎症聚集物的缓解需要LPM介导的moC招募，这对于纤维蛋白溶解介导的resMφ-aggregates的分解和防止腹膜的明显炎症是必不可少的。因此，resMφ-aggregates提供了一个物理支架，能够有效地控制腹膜感染，对其他体腔，如胸膜腔或脑室的抗菌免疫具有影响。

据悉，腹膜免疫细胞在平衡状态下不固定地驻扎在腹膜液中。

附：英文原文

Title: Resident macrophage-dependent immune cell scaffolds drive anti-bacterial defense in the peritoneal cavity

Author: Adrián Vega-Pérez, Laura H. Villarrubia, Cristina Godio, Alejandra Gutiérrez-González, Lidia Feo-Lucas, Margarita Ferriz, Natalia Martínez-Puente, Julieta Alcaín, Alfonso Mora, Guadalupe Sabio, María López-Bravo, Carlos Ardavín

Issue&Volume: 2021-10-29

Abstract: Peritoneal immune cells reside unanchored within the peritoneal fluid in homeostasis.Here, we examined the mechanisms that control bacterial infection in the peritoneumusing a mouse model of abdominal sepsis following intraperitoneal Escherichia coli infection. Whole-mount immunofluorescence and confocal microscopy of the peritonealwall and omentum revealed that large peritoneal macrophages (LPMs) rapidly clearedbacteria and adhered to the mesothelium, forming multilayered cellular aggregatescomposed by sequentially recruited LPMs, B1 cells, neutrophils, and monocyte-derivedcells (moCs). The formation of resident macrophage aggregates (resMφ-aggregates) requiredLPMs and thrombin-dependent fibrin polymerization. E. coli infection triggered LPM pyroptosis and release of inflammatory mediators. Resolutionof these potentially inflammatory aggregates required LPM-mediated recruitment ofmoCs, which were essential for fibrinolysis-mediated resMφ-aggregate disaggregationand the prevention of peritoneal overt inflammation. Thus, resMφ-aggregates providea physical scaffold that enables the efficient control of peritoneal infection, withimplications for antimicrobial immunity in other body cavities, such as the pleuralcavity or brain ventricles.

DOI: 10.1016/j.immuni.2021.10.007

Source: https://www.cell.com/immunity/fulltext/S1074-7613(21)00444-1