HUMAN BLOOD GROUP-B-ACTIVE GANGLIO-GLYCOSPHINGOLIPID IN RAT GLIOMA

A human blood group B-active glycosphingolipid, belonging to the gangl io-series, was isolated from rat glioma cell line RG2 subcutaneous iso grafts. The oligosaccharide structure of the glycosphingolipid was com pletely characterized as ha1-2)Galbeta1-3GalNAcbeta1-4Galbeta1-4Glcbet a1-1' ceramide by NMR spectrometry, negative fast atom bombardment-mas s spectrometry, sequential degradation by glycosidases and methylation analysis. Human blood group B antigenicity and the activity of this g lycosphingolipid were confirmed by immunostaining on thin-layer chroma tography and the inhibition of hemagglutination, respectively. Althoug h the lipid has been detected in rat granuloma, bone marrow cells, spl een, thymus, ascites hepatoma cells and gastric mucosa, this is the fi rst report of the occurrence of the B-active lipid in glioma.