IL17A and colitis: Treatment with an antibiotic cocktail (including ampicillin, metronidazole, neomycin, and vancomycin) in drinking water ameliorated colitis after DSS exposure, as evidenced by minor weight loss, decreased histological scores, mild impairment of mucosal barrier, and reduced expression of proinflammatory cytokines (e.g., IL-1β, IL-6, IL-17A, and IFN-γ) in the colon tissues of antibiotics-treated Cd177−/− mice compared with those in control Cd177−/− mice (Supplementary Figure S6b-f).