STRUCTURAL-ANALYSIS ON THE SUGAR CHAINS OF ALPHA(1)-ANTITRYPSIN FROM PATIENTS WITH HEPATOCELLULAR-CARCINOMA

Chemical structures of the sugar chains of alpha1-antitrypsin (AAT) fr om patients with hepatocellular carcinoma (HCC) with different affinit y for Lens culinaris agglutinin (LCA) were examined by pyridylaminatio n of their oligosaccharides and stepwise exoglycosidase digestion. By using reversed-phase and size-fractionation high-performance liquid ch romatography systems we confirmed that the LCA-reactive species of AAT from patients with HCC contained a biantennary sugar chain with a fuc ose residue at the innermost N-acetylglucosamine residue, pha1-3)Manbe ta1-4GlcNAcbeta1-4(Fucalpha1-6)GlcNAc, as a major component, and a bia ntennary sugar chain without a fucose residue, cbeta1-2Manalpha1-3)Man beta1-4GlcNAcbeta1-4GlcNAc, as a minor component. Thus, present result s indicate that a characteristic feature of the carbohydrate chains of AAT from patients with HCC is an increment in fucosylation.