MUC5AC and colitis: Mice genetically deficient in mucin production (Muc2KO) are highly susceptible to C. rodentium infection.36 Our experimental results show that colonization of A. muciniphila in mice (on normal diet) results in increased goblet cells and mucin production in Citrobacter-infected mice and these mice are protected from disease, suggesting that one of the mechanisms underlying the protective effects of A. muciniphila on C. rodentium infection and colitis involved regulation of the mucus barrier in the gut.