IL33 and inflammatory bowel disease: As shown in Fig. 1a−d, we found that the serum IL-33 levels (mean) in patients with IBD were lower than those in normal controls (P < 0.012: normal controls, 0.513 ± 0.665 ng/ml; IBD, 0.242 ± 0.436 ng/ml; CD, 0.381 ± 0.582 ng/ml; UC, 0.185 ± 0.394 ng/ml; intestinal BD, 0.160 ± 0.229 ng/ml), whereas the sST2 levels in patients with IBD were higher than those in normal controls (P < 0.001: normal controls, 4.246 ± 0.737 ng/ml; IBD, 5.344 ± 1.162 ng/ml; CD, 5.110 ± 1.054 ng/ml; UC, 5.581 ± 1.169 ng/ml; BD, 5.214 ± 1.174 ng/ml).