IL4 and inflammatory bowel disease: In both intestinal biopsies from IBD patients as in the colon of SAMP/YitFc mice, which spontaneously develop colitis resembling human CD, ST2/IL-33 signaling caused an eosinophilic infiltration and activation coinciding with a Th2 mediated immune response resulting in the release of IL-4, IL-5 and IL-13 (101–103).