DIFFERENTIAL INTERACTIONS OF ABH-RELATED BLOOD GROUP GLYCOLIPIDS WITH ENTEROTOXINS FROM THE CHOLERA TOXIN FAMILY.
Estela M Galván, Claudio D. Diema, Clara G. Monferran, and German A. Roth.
The ability of ABH and Lewis blood group-active glycolipids from different sources to bind heat-labile enterotoxin of Escherichia coli (LTh) and cholera toxin (CT) was studied. Neutral monofucosylated ABH-active glycolipids from pig intestine or human pancreas are capable to bind both toxins. However, ABH-active glycolipids obtained form rabbit intestine or human erythrocytes, only bind LTh but not CT. Lewis blood-group glycolipids from human intestine do not interact with either both toxins.
Our results suggest that the different binding specificities showed by CT and LTh could be due to differences in the internal oligosaccharide structure of the ABH-related glycolipids. The CT binding to pig intestinal and human pancreas glycolipids can be due to the type of disaccharide chain precursor that are mainly based on type 1, meanwhile CT do not interact with glycolipids from rabbit intestine or human erythrocytes which are mainly of type 2. Also, the presence of a second internal fucose abolishes the interaction of the ABH-active glycolipids with both toxins.
