{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Sassone-Corsi M"],"funding":["NIAID NIH HHS","Israel Science Foundation","HHS | NIH | National Institute of Allergy and Infectious Diseases","Broad-ISF exchange","Cancer Research Institute","HHS | NIH | National Institute of Allergy and Infectious Diseases (NIAID)"],"pagination":["e2209624119"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC9565271"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["119(41)"],"pubmed_abstract":["T cells that express the transcription factor RORγ, regulatory (Treg), or conventional (Th17) are strongly influenced by intestinal symbionts. In a genetic approach to identify mechanisms underlying this influence, we performed a screen for microbial genes implicated, in germfree mice monocolonized with <i>Escherichia coli</i> Nissle. The loss of capsule-synthesis genes impaired clonal expansion and differentiation of intestinal RORγ<sup>+</sup> T cells. Mechanistic exploration revealed that the capsule-less mutants remained able to induce species-specific immunoglobulin A (IgA) and were highly IgA-coated. They could still trigger myeloid cells, and more effectively damaged epithelial cells in vitro. Unlike wild-type microbes, capsule-less mutants were mostly engulfed in intraluminal casts, large agglomerates composed of myeloid cells extravasated into the gut lumen. We speculate that sequestration in luminal casts of potentially harmful microbes, favored by IgA binding, reduces the immune system's actual exposure, preserving host-microbe equilibrium. The variable immunostimulation by microbes that has been charted in recent years may not solely be conditioned by triggering molecules or metabolites but also by physical limits to immune system exposure."],"journal":["Proceedings of the National Academy of Sciences of the United States of America"],"pubmed_title":["Sequestration of gut pathobionts in intraluminal casts, a mechanism to avoid dysregulated T cell activation by pathobionts."],"pmcid":["PMC9565271"],"funding_grant_id":["AI150686","3114831","R01 AI125603","Irvington Fellowship","AI125603","8165162","R01 AI150686"],"pubmed_authors":["Simon A","Ortiz-Lopez A","Mathis D","Chen F","Benoist C","Ramanan D","Sassone-Corsi M","Azriel S","Yissachar N"],"additional_accession":[]},"is_claimable":false,"name":"Sequestration of gut pathobionts in intraluminal casts, a mechanism to avoid dysregulated T cell activation by pathobionts.","description":"T cells that express the transcription factor RORγ, regulatory (Treg), or conventional (Th17) are strongly influenced by intestinal symbionts. In a genetic approach to identify mechanisms underlying this influence, we performed a screen for microbial genes implicated, in germfree mice monocolonized with <i>Escherichia coli</i> Nissle. The loss of capsule-synthesis genes impaired clonal expansion and differentiation of intestinal RORγ<sup>+</sup> T cells. Mechanistic exploration revealed that the capsule-less mutants remained able to induce species-specific immunoglobulin A (IgA) and were highly IgA-coated. They could still trigger myeloid cells, and more effectively damaged epithelial cells in vitro. Unlike wild-type microbes, capsule-less mutants were mostly engulfed in intraluminal casts, large agglomerates composed of myeloid cells extravasated into the gut lumen. We speculate that sequestration in luminal casts of potentially harmful microbes, favored by IgA binding, reduces the immune system's actual exposure, preserving host-microbe equilibrium. The variable immunostimulation by microbes that has been charted in recent years may not solely be conditioned by triggering molecules or metabolites but also by physical limits to immune system exposure.","dates":{"release":"2022-01-01T00:00:00Z","publication":"2022 Oct","modification":"2025-04-04T08:47:02.235Z","creation":"2025-04-04T08:47:02.235Z"},"accession":"S-EPMC9565271","cross_references":{"pubmed":["36201539"],"doi":["10.1073/pnas.2209624119"]}}