TGFB1 and colitis: Our finding that the TGF-β–activating integrin αvβ8 is highly expressed and functionally important on specialized tolerogenic DCs in the intestine correlates with our previous findings that Itgb8 (CD11c-Cre) mice develop severe colitis associated with reduced levels of total Foxp3+ Tregs in the colonic lamina propria.9