Guan et al. showed that the percentages of CD11b+Gr-1+MDSCs and other subsets (CD11b+Ly6C+ and CD11b+Ly6G+MDSCs) were increased in the spleen and/or colonic lamina propria mononuclear cells in colitis mice, which correlated with the severity of intestinal inflammation. Here, ITGAM is linked to colitis.