加拿大卡尔加里大学Kathy D. McCoy、瑞士联邦理工学院Nicola L. Harris研究组合作揭示小肠常驻嗜酸性粒细胞在微生物定植后维持肠道稳态。相关论文于2022年6月15日发表在《免疫》杂志上。

流式细胞术和整体成像鉴定了产后微生物定植之前存在于肠道固有层中的嗜酸性粒细胞。肠道组织的显微镜检查、转录组分析和质谱分析显示，嗜酸性粒细胞缺陷小鼠的绒毛变钝、细胞外基质改变、上皮细胞更新减少、胃肠动力增加和脂质吸收减少。从机制上讲，肠上皮细胞以微生物群依赖性方式释放 IL-33，从而导致嗜酸性粒细胞活化。无菌小鼠的定植表明，响应微生物的嗜酸性粒细胞活化调节绒毛大小改变、巨噬细胞成熟、上皮屏障完整性和肠道转运。

总的来说，他们的研究结果证明了嗜酸性粒细胞在促进宿主和微生物群之间的共生相互作用中的关键作用，并为它们在小肠中早期募集的功能意义提供了理论依据。

据悉，肠道内有大量常驻嗜酸性粒细胞，但尚未探索肠道嗜酸性粒细胞的功能。

附：英文原文

Title: Small intestinal resident eosinophils maintain gut homeostasis following microbial colonization

Author: Aline Ignacio, Kathleen Shah, Jeremiah Bernier-Latmani, Yasmin Kller, Gillian Coakley, Mati Moyat, Romain Hamelin, Florence Armand, Nick C. Wong, Hena Ramay, Carolyn A. Thomson, Regula Burkhard, Haozhe Wang, Antoine Dufour, Markus B. Geuking, Braedon McDonald, Tatiana V. Petrova, Nicola L. Harris, Kathy D. McCoy

Issue&Volume: 2022-06-15

Abstract: The intestine harbors a large population of resident eosinophils, yet the functionof intestinal eosinophils has not been explored. Flow cytometry and whole-mount imagingidentified eosinophils residing in the lamina propria along the length of the intestineprior to postnatal microbial colonization. Microscopy, transcriptomic analysis, andmass spectrometry of intestinal tissue revealed villus blunting, altered extracellularmatrix, decreased epithelial cell turnover, increased gastrointestinal motility, anddecreased lipid absorption in eosinophil-deficient mice. Mechanistically, intestinalepithelial cells released IL-33 in a microbiota-dependent manner, which led to eosinophilactivation. The colonization of germ-free mice demonstrated that eosinophil activationin response to microbes regulated villous size alterations, macrophage maturation,epithelial barrier integrity, and intestinal transit. Collectively, our findings demonstratea critical role for eosinophils in facilitating the mutualistic interactions betweenthe host and microbiota and provide a rationale for the functional significance oftheir early life recruitment in the small intestine.

DOI: 10.1016/j.immuni.2022.05.014

Source: https://www.cell.com/immunity/fulltext/S1074-7613(22)00234-5