Characterization of porcine kidney neutral glycosphingolipids: identification of a carbohydrate antigen recognized by human natural antibodies

We have investigated the glycosphingolipids of pig kidney with a special interest in identifying compounds which may be involved in the rejection of tissue in xenotransplantation. Nine neutral glycosphingolipids have been characterized in porcine kidney and structurally characterized by a combination of techniques including¹H-NMR, permethylation analysis and thin-layer chromatography (TLC) immunostaining with carbohydrate sequence-specific monoclonal antibodies. The major components are members of the globo family and represent the human p^k and P antigens. Three other compounds were found to contain a neolacto core structure; the major neolacto compound carries a nonreducing terminal epitope (Gal1-3Gal1-4GlcNAc) recognized by the naturally-occurring human antibody, anti-Gal, and a second neolacto compound carries the blood group A trisaccharide (GalNAc1-3(Fuc1-2)Gal). These results are discussed with respect to tissue transplantation.