III 6NeuAcLc 4Cer in human SW1116 colorectal carcinoma cells: A possible oncofetal antigen that is not dependent on Lewis gene expression

Abstract

Monospecific rabbit antibodies directed against the human milk sialyloligosaccharides III 6NeuAcLcOse 4 (sialyltetrasaccharide b), IV 3NeuAcLcOse 4 (sialyltetrasaccharide a), and IV 6NeuAcnLc 4Ose (sialyltetrasaccharide c) were used to detect their homologous haptens as gangliosides or ganglioside-derived sialyloligosaccharides from the human colorectal carcinoma cell line SW1116. III 6NeuAcLc 4Cer was first detected in human meconium [ P. A. Prieto and D. F. Smith (1985) Arch. Biochem. Biophys. 241, 281–289 ], and its presence in a total ganglioside fraction of SW1116 cells together with its absence from a total lipid extract of normal human intestinal mucosa are consistent with III 6NeuAcLc 4Cer being a tumor-associated oncofetal antigen. IV 3NeuAcLc 4Cer, a ganglioside in human meconium [ P. A. Prieto and D. F. Smith (1986) Arch. Biochem. Biophys. 249, 243–253 ], was also detected in SW1116 cells; an observation that is consistent with its being the immediate precursor to the sialyl-Le a ganglioside in SW1116 cells. Specific antisera against sialylated type 1 oligosaccharide chains whose expression is independent of the Lewis gene fucosyltransferase may be useful diagnostic reagents for oncofetal, carbohydrate antigens.