Loss of Shp2 in macrophages decreases the susceptibility of mouse colitis. Mice were challenged with 2.5% DSS in drinking water for 7 d. (A) Body weight loss, diarrhea, and rectal bleeding were monitored daily. Data are accumulated from three independent experiments with n = 4–9 mice/group in each experiment. (B) Colon length was measured at day 7. (C) Colon sections were analyzed for histological damage. Bars, 100 µm. (D) Periodic acid–Schiff staining of colon sections. Bars, 100 µm. (E) The expression of bacterial 16S rRNA in spleens was determined by qPCR. (F) Mice were challenged with 4% DSS for 7 d, and the survival of mice was monitored. n = 7–13. Data are mean ± SEM and are representative of three independent experiments. *, P < 0.05; **, P < 0.01; two-tailed unpaired Student’s t test (A–C and E) and log-rank test (F).