Fig. 1: Helicobacter species induce inflammation, dysbiosis, and colon tumorigenesis in IL10^−/− mice.

a Colitis scores for IL10^−/− mice compared to IL10^−/− (IL10^−/−I) and IL10^+/− (IL10^+/−I) infected with two Helicobacter species: H. typhlonius and H. mastomyrinus. To account for disease, each of the following parameters was given a value of either 0 or 1: stool with excreted mucus, rectal inflammation, rectal prolapse, bloody stool, over 5% weight lost, and moribund, leading to a maximum grade of 6. N = 33 mice were examined. Data are presented as mean values + SEM. Two-way ANOVA p < 0.0001. b Colon length measured in 9-week-old Helicobacter-infected or -uninfected IL10^−/− mice. Shortening of the colon is indicative of colitis. N = 30 mice were examined. c Polyp number was analyzed in the colon of 9-week-old Helicobacter-infected (IL10^−/− and IL10^+/− littermates) or -uninfected IL10^−/− mice. N = 35 mice were examined. d 3- or 4-week-old IL10^−/− or IL10^+/− mice were inoculated by oral gavage with H. hepaticus or C. rodentium, and colitis was monitored for 6 weeks. N = 34 mice were examined. Data are presented as mean values ± SEM. e Colon length measured on 10-week-old mice from the indicated genotypes and treatments. N = 24 mice were examined. f Polyp number was analyzed in the colon of 10-week-old mice from the indicated genotypes and treatments. N = 30 mice were examined. g Principal coordinate analysis of 16 S rRNA gene-sequencing analysis of fecal bacteria obtained from IL10^−/− mice infected with H. hepaticus. Fecal samples were obtained before (day 0) and after H. hepaticus infection, for four consecutive weeks. Each dot represents one mouse. N = 8 mice were examined. h Same as g, except that IL10^+/− mice were used. N = 3 mice were examined. Data in b, c, e and f were analyzed using the two-sided non-parametric t-test Mann–Whitney; *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.