An immunochemical study of the human blood group P1, P, and PK glycosphingolipid antigens.
The erythrocyte PK and P blood group antigens have been identified as ceramide trihexoside (CTH), Gal-(alpha, 1 leads to 4)Gal(beta, 1 leads to 4)Glc-Cer, and globoside, GalN-Ac(beta, 1 leads to 3)Gal(alpha, 1 leads to 4)Gal(beta, 1 leads to 4)Glc-Cer, respectively, and the following structure has been proposed for the P1 antigen: Gal(alpha, 1 leads to 4)Gal(beta, 1 leads to 4)GlcNAc(beta, 1 leads to 3)Gal(beta, 1 leads to 4)Glc-Cer. Although the P1 and PK determinants have identical terminal disaccharides, CTH did not inhibit anti-P1. The P1 glycolipid and hydatid cyst glycoprotein inhibited the agglutination of P1K erythrocytes by anti-P1 and unabsorbed anti-P1PPK sera, but neither antigen inhibited a specific anti-PK serum. The P1 and PK glycolipids were equally effective in inhibiting the hemagglutinating activity of a lectin with alpha-galactosyl specificity obtained from ova of Salmo trutta. Anti-P sera were inhibited most effectively by human erythrocyte globoside, and to a lesser extent by Forssman glycolipid and rat kidney globoside. In the latter glycolipid the linkage between the internal galactosyl residues is alpha, 1 leads to 3, rather than alpha, 1 leads to 4, as in erythrocyte globoside. No cross-reactions between P and P1 or PK antigens were detected. New hypotheses are offered to explain the genetic regulation and biosynthesis of the P1, P, and PK antigens.
D000941:Antigens; D001789:Blood Group Antigens; D002241:Carbohydrates / Q000032:analysis; D002518:Ceramides / Q000032:analysis; D004912:Erythrocytes / Q000032:analysis; D006028:Glycosphingolipids / Q000097:blood* / Q000276:immunology; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D010127:P Blood-Group System
D000941:Antigens; D001789:Blood Group Antigens; D002241:Carbohydrates; D002518:Ceramides; D006028:Glycosphingolipids; D010127:P Blood-Group System