The disease activity index was calculated as the average of the diarrhea score and rectal bleeding score and was significantly attenuated in IL-4Rα-/- colitis mice compared with WT colitis mice (Figure 1B; 3.7 ± 0.2 in WT colitis, 1.1 ± 0.3 in IL-4Rα-/- colitis on day 7; p < 0.001). Here, IL4R is linked to colitis.