A new human erythrocyte variant (Ph) containing an abnormal membrane sialoglycoprotein.
1. A new human erythrocyte variant (Ph) is described. The variant contains an unusual sialic acid-rich glycoprotein in addition to the blood-group-MN([unk])- and blood-group-Ss(delta)-active sialoglycoproteins found in normal erythrocytes. 2. The unusual component Ph has an apparent mol.wt. of 32000 on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. The Ph component is not degraded during trypsin treatment of intact erythrocytes. 3. The Ph component was labelled by lacto-peroxidase-mediated radioiodination of intact erythrocytes and was found to be present in amounts approximately equimolar to alpha-sialoglycoprotein in the variant erythrocytes. 4. The Ph component had receptors for the lectins from Maclura aurantiaca (osage orange) and Triticum vulgaris (wheat-germ), but lacked a receptor for the Phaseolus vulgaris (red kidney bean) lectin, suggesting that it carries only O-linked oligosaccharides. 5. The presence of the Ph component in these erythrocytes does not correspond to any of the known blood-group-MNSs-related antigens examined. 6. We suggest that this component may be a hybrid polypeptide containing the N-terminal portion derived from normal delta-sialoglycoprotein, and the C-terminal portion from normal alpha-sialoglycoprotein, in a manner similar to the anti-Lepore haemoglobin.
D001789:Blood Group Antigens; D004591:Electrophoresis, Polyacrylamide Gel; D006021:Glycophorins / Q000032:analysis / Q000235:genetics*; D006801:Humans; D007106:Immune Sera; D037102:Lectins; D008951:MNSs Blood-Group System; D008957:Models, Genetic; D010127:P Blood-Group System; D011975:Receptors, Mitogen / Q000032:analysis; D012795:Sialoglycoproteins / Q000235:genetics*
D001789:Blood Group Antigens; D006021:Glycophorins; D007106:Immune Sera; D037102:Lectins; D008951:MNSs Blood-Group System; D010127:P Blood-Group System; D011975:Receptors, Mitogen; D012795:Sialoglycoproteins