Chronic intestinal inflammation in mice on day 29 after the beginning of DSS treatment. (A) Cumulative change of body weight (BW) in the course of dextran sodium sulfate (DSS) treatment from three independent experiments; n = 15 mice analyzed. (B) Serum IL-6 levels in control and DSS-treated mice (n = 8). (C) Immunohistochemical analysis of intestinal inflammation (H&E). Inflammation sites are marked by dotted lines. Cecum: Arrow points to the site of severe transmural inflammation with loss of entire crypts and endothelium and infiltration of inflammatory cells. Colon: Arrow points to severe submucosal inflammation with loss of crypts while the surface epithelium is still intact and to infiltration of inflammatory cells.