Figure 3.

Intestinal colonization with E. coli 541–15 prevents colitis by inducing IL-10 production by CX3CR1+ macrophages. IL-10flox/- (CX3 IL-10-/-) and IL-10flox/+ (WT) littermate CX3CR1-CreERT2 mice were colonized with E. coli 541–15 and 3 days later 2% DSS was provided. At day 7 of DSS treatment, samples were collected. 3 days before colonization and every 2 days throughout the experiment 4OHT was injected to both groups. (a) Representative H&E staining of distal colons. Scale bars represent 50 μm. (b) Histopathology scores. (c) Colon lengths. Colon lamina propria cells were isolated. (d) Number of immune cells. (e) Flow cytometry and frequencies of Th1 and Tregs. Each replicate is a biologically independent sample. Individual dots represent samples from individual mice. Data are shown as individual values and mean, compared by two-tailed unpaired t-test or two-way ANOVA with Fisher’s LSD post hoc test. The results are representative of at least two independent experiments. *P < .05 was considered statistically significant; **P <.01; ***P < .001. See also Figure S3.