Griffonia simplicifolia agglutinin-2-binding glycoprotein as a novel carbohydrate antigen of human colonic carcinoma.

Griffonia simplicifolia agglutinin-2-binding glycoprotein (GBG) in human colonic carcinoma was examined immunochemically and histochemically, GBG was extracted from colonic carcinoma as a serum-type glycoprotein of 160 kilodaltons. GBG was not identical with carcinoembryonic antigen (CEA), since its molecular weight and localization in tissue sections were different from those of CEA. The non-reducing terminals of GBG probably carry N-acetylglucosamine, but not blood group determinants. Furthermore, GBG was released by phosphatidylinositol-specific phospholipase C from cell membrane. GBG was suggested to be anchored to the membrane via linkage to a glycosyl-phosphatidylinositol molecule. Among colonic carcinoma-associated antigens, serum-type glycoproteins having N-acetylglucosamine at non-reducing terminals have not previously been reported. GBG is a novel carbohydrate antigen of human colonic carcinoma.

carcinoembryonic antigen

fucose

galactose

N‐acetylgalactosamine

glucose

N‐acetylglucosamine

Griffonia simplicifolia agglutinin‐2

horseradish peroxidase

kilodaltons

2‐mercaptoethanol

N‐acetylneuraminic acid

polyacrylamide gel electrophoresis

phosphatidylinositol‐specific phospholipase C

peptide: N‐glycosidase F

sodium dodecyl sulfate

Ulex europaeus agglutinin‐1