(1) Microbe-derived riboflavin metabolites promote development of mucosal-associated invariant T (MAIT) cells.
(2) Commensal-induced cytokines IL-1β and IL-23 promote IL-17A production from γδT cells.
(3) ILC3-derived IL-22 prevents translocation of Alcaligenes spp. to lymphoid architecture and promotes epithelial cell production of serum amyloid A (SAA)1/2 to license IL-17A production from Th17 cells.
(4) ILC3-expressing MHC-II delete activated commensal-specific CD4+ T cells.
(5) Early life colonization limits iNKT expansion and pathogenic function within the colonic lamina propria and lungs.