C. butyricum, a butyrate-producing bacteria, reduces dextran sulfate-induced enteritis; however, it has been reported that TGF-β and its induction of regulatory T cells (Treg) via proteoglycans are involved in this mechanism.20 This suggests that butyrate-producing bacteria play a major role in the prophylactic treatment of patients with compromised immunity in whom increased mucosal permeability is an important etiological factor. This evidence concerns the gene TGFB1 and enteritis.