{"title":"Extracellular vesicles of Bacteroides uniformis induce M1 macrophage polarization and aggravate gut inflammation during weaning","authors":"","doi":"10.1016/j.mucimm.2024.05.004","DOIUrl":null,"url":null,"abstract":"<div><div>Weaning process is commonly associated with gastrointestinal inflammation and dysbiosis of the intestinal microbes. In particular, the impact of gut bacteria and extracellular vesicles on the etiology of intestinal inflammation during weaning is not well understood. We have uncovered a potential link between gut inflammation and the corresponding variation of macrophage bacterial sensing and pro-inflammatory polarization during the weaning process of piglets through single-cell transcriptomic analyses. We conducted a comprehensive analysis of bacterial distribution across the gastrointestinal tract and pinpointed <em>Bacteroides uniformis</em> enriching in piglets undergoing weaning. Next, we found out that exposure to <em>B. uniformis</em>-derived extracellular vesicles (BEVs) exacerbated gut inflammation in a murine colitis model while recruiting and polarizing intestinal macrophages toward a pro-inflammatory phenotype. BEVs modulated the function of macrophages cultured <em>in vitro</em> by suppressing the granulocyte-macrophage colony-stimulating factor/signal transducer and activator of transcription 5/arginase 1 pathway, thereby affecting polarization toward an M1-like state. The effects of BEVs were verified both in the macrophage clearance murine model and by using an adoptive transfer assay. Our findings highlight the involvement of BEVs in facilitating the polarization of pro-inflammatory macrophages and promoting gut inflammation during weaning.</div></div>","PeriodicalId":18877,"journal":{"name":"Mucosal Immunology","volume":null,"pages":null},"PeriodicalIF":7.9000,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Mucosal Immunology","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S193302192400045X","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"IMMUNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Weaning process is commonly associated with gastrointestinal inflammation and dysbiosis of the intestinal microbes. In particular, the impact of gut bacteria and extracellular vesicles on the etiology of intestinal inflammation during weaning is not well understood. We have uncovered a potential link between gut inflammation and the corresponding variation of macrophage bacterial sensing and pro-inflammatory polarization during the weaning process of piglets through single-cell transcriptomic analyses. We conducted a comprehensive analysis of bacterial distribution across the gastrointestinal tract and pinpointed Bacteroides uniformis enriching in piglets undergoing weaning. Next, we found out that exposure to B. uniformis-derived extracellular vesicles (BEVs) exacerbated gut inflammation in a murine colitis model while recruiting and polarizing intestinal macrophages toward a pro-inflammatory phenotype. BEVs modulated the function of macrophages cultured in vitro by suppressing the granulocyte-macrophage colony-stimulating factor/signal transducer and activator of transcription 5/arginase 1 pathway, thereby affecting polarization toward an M1-like state. The effects of BEVs were verified both in the macrophage clearance murine model and by using an adoptive transfer assay. Our findings highlight the involvement of BEVs in facilitating the polarization of pro-inflammatory macrophages and promoting gut inflammation during weaning.
期刊介绍:
Mucosal Immunology, the official publication of the Society of Mucosal Immunology (SMI), serves as a forum for both basic and clinical scientists to discuss immunity and inflammation involving mucosal tissues. It covers gastrointestinal, pulmonary, nasopharyngeal, oral, ocular, and genitourinary immunology through original research articles, scholarly reviews, commentaries, editorials, and letters. The journal gives equal consideration to basic, translational, and clinical studies and also serves as a primary communication channel for the SMI governing board and its members, featuring society news, meeting announcements, policy discussions, and job/training opportunities advertisements.