Aquaporin-8 expression is reduced in ileum and induced in colon of patients with ulcerative colitis

Figure 2 A: Immunohisto-chemical detection of AQP8 in normal colonic mucosa. Some subepithelial mononuclear cells (MNC) in the lamina propria are positive (red immunostaining). Epithelial cells at the mucosal surface display very weak signals; B: Immunohistochemical detection of AQP8 in an inactive colonic area in a case with ulcerative colitis. A slight increase in staining intensity is apparent as compared with A. The intestinal epithelium as well as a subset of lamina propria MNCs are positive for AQP8; C: Immunohistochemical detection of AQP8 in an actively inflamed colonic area in a case with ulcerative colitis. A strong expression of AQP8 is apparent. Intestinal epithelial cells as well as numerous MNCs within the inflamed lamina propria are immunostained; D: Corresponding negative control to 2C with use of normal rabbit immunoglobulins as primary reagent. A-C: Alkaline phosphatase, original magnification x 40, respectively.