Identification of the N-Acetylcysteine Sensitive Receptor Endoglin in Hepatic Stellate Cells

Introduction: TGF-β is the major cytokine regulating hepatic stellate cell (HSC) function in the course of liver fibrogenesis. In a previous study we could show that the reducing substance N-Acetylcysteine (NAC) is able to block TGF-β signalling in HSC by different means than modification of the cellular redox state. Analyzing the TGF-β receptor proteins ALK5 (type I receptor), RII (type II receptor) and betaglycan (type III receptor) with receptor specific antibodies revealed no differences between treated and untreated cells. In contrast, using an antibody (sc–6199), which recognizes both type III receptors, betaglycan and endoglin, we detected a redox sensitive protein, most likely endoglin. Subsequently, we cloned the rat endoglin cDNA from HSC and MFB.