IMMUNOHISTOCHEMICAL LOCALIZATION OF TRANSFORMING GROWTH-FACTOR-BETA RECEPTOR-I AND RECEPTOR-II IN INFLAMMATORY BOWEL-DISEASE

Transforming growth factor (TGF)-beta inhibits cell proliferation and stimulates cell differentiation. For the signal transduction of TGF-be ta, receptors I and II are required. The present study discloses the i mmunohistochemical localization of TGF-beta receptors I and II in infl ammatory bowel disease. In the normal colon and small intestinal tissu e, TGF-beta receptors were expressed in the epithelial cells in the up per crypts. In inflammatory bowel disease, a disordered expression pat tern of receptors I and II was observed in the epithelial cells. Fibro blasts in the area of early stage fibrosis were positive for both rece ptors, while fibroblasts in area of advanced fibrosis lacked immunorea ctivity for both receptors. Our study suggests that TGF-beta receptors I and II are important for the initial step of fibrosis.