SIMULTANEOUS EXPRESSION BY PORCINE AORTA ENDOTHELIAL-CELLS OF GLYCOSPHINGOLIPIDS BEARING THE MAJOR EPITOPE FOR HUMAN XENOREACTIVE ANTIBODIES (GAL-ALPHA-1-3GAL), BLOOD-GROUP-H DETERMINANT AND N-GLYCOLYLNEURAMINIC ACID

Glycosphingolipids were isolated from primary cultures of porcine endo thelial cells labelled with C-14-galactose or C-14-glucosamine. They w ere characterized by their mobility on thin layer chromatogram, their sensitivity to exoglycosidases, and their labelling with antibodies. I n addition to the major glycosphingolipids, globotetra- and globotriao sylceramide, minor ones were identified as penta- and heptaglycosylcer amide of the neolactoseries terminated by either Gal alpha 1-3Gal- (xe noreactive epitope) or Fuc alpha 1-2Gal- (H determinant). Two ganglios ides were found, GM3 and GD3, and N-glycolylneuraminic acid was their major sialic acid. Therefore, porcine endothelial cells differ from hu man endothelial cells by expression of glycosphingolipids that are abs ent in man: two Gal alpha 1-3Gal-terminated glycolipids recognized by human natural antibodies, and two N-glycolylneuraminic acid-terminated gangliosides which are potent immunogens.