The influence of alpha- and beta-galactose residues and sialic acid O-acetyl groups of rat erythrocytes on the interaction with peritoneal macrophages.

The significance of glycoconjugates on the surface of rat erythrocytes was studied in the interaction of these cells with homologous peritoneal macrophages. The erythrocytes exposing terminal alpha-galactose and thus of B blood group specificity, as well as sialic acid are not bound by the macrophages. beta-Galactose residues exposed by sialidase induced strong binding and additional alpha-galactosidase treatment enhanced the binding. beta-Galactose exposed on glycolipids after pronase and alpha-galactosidase treatment induced no binding. An intact protein core of the glycoproteins on the erythrocyte surface was necessary for interaction with macrophages. Partial de-O-acetylation of sialic acids prior to sialidase treatment stimulated subsequent binding of the erythrocytes.