title: Exopolysaccharide fromBacillus subtilisInduces Anti-Inflammatory M2 Macrophages That Prevent T Cell-Mediated Disease.
abstract: Commensal bacteria contribute to immune homeostasis in the gastrointestinal tract; however, the underlying mechanisms for this are not well understood. A single dose of exopolysaccharide (EPS) from the probiotic spore-forming bacteriumBacillus subtilisprotects mice from acute colitis induced by the enteric pathogenCitrobacter rodentiumAdoptive transfer of macrophage-rich peritoneal cells from EPS-treated mice confers protection from disease to recipient mice. In vivo, EPS induces development of anti-inflammatory M2 macrophages in a TLR4-dependent manner, and these cells inhibit T cell activation in vitro and inC. rodentium-infected mice. In vitro, M2 macrophages inhibit CD4+and CD8+T cells. The inhibition of CD4+T cells is dependent on TGF-β, whereas inhibition of CD8+T cells is dependent on TGF-β and PD-L1. We suggest that administration ofB. subtilisEPS can be used to broadly inhibit T cell activation and, thus, control T cell-mediated immune responses in numerous inflammatory diseases.
authors.affiliation: Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL 60153.
authors.forename: Mallory L
authors.initials: ML
authors.lastname: Paynich
authors.affiliation: Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL 60153.
authors.forename: Sara E
authors.initials: SE
authors.lastname: Jones-Burrage
authors.affiliation: Department of Microbiology and Immunology, Loyola University Chicago, Maywood, IL 60153 kknight@luc.edu.
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Knight
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D001412:Bacillus subtilis / Q000276:immunology; D044082:Citrobacter rodentium; D003092:Colitis / Q000276:immunology* / Q000382:microbiology; D004195:Disease Models, Animal; D004756:Enterobacteriaceae Infections / Q000276:immunology / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D000069196:Gastrointestinal Microbiome / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D060888:Real-Time Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D011135:Polysaccharides, Bacterial; C085953:exopolysaccharide, Bacillus