Background: This report describes the characterization of polyagglutinable red cells (RBCs), identified in two generations of a Polish family.
Case report: Untreated and modified RBCs of the proposita (TS) were tested by serologic methods, using human sera, antibodies, lectins, and inhibitors of agglutination. Moreover, glycophorins were characterized by sodium docecyl sulfate-polyacrylamide gel electrophoresis and Western blotting, and glycolipids were purified, fractionated by thin-layer chromatography, and detected with Ricinus communis agglutinin I (RCA-I, specific for galactose residues) and Griffonia simplicifolia IB4 lectin (GSL-IB4, specific for Gal alpha1-3Gal- structure). Some of the experiments were also performed on RBCs of members of TS's family.
Results: Polyagglutination, found in four members of TS's family, was identified as the second case of an earlier described NOR polyagglutination. The polyagglutination was decreased by treating the RBCs with alpha-galactosidase and was inhibited by a neutral glycolipid fraction from NOR+ RBCs. Detection of neutral glycolipids of TS's RBCs on the thin-layer plate by RCA-I and GSL-IB4 revealed the presence of components that were not detectable in control RBCs. Moreover, Western blotting of RBC membranes from five family members with glycophorin monoclonal antibodies and agglutination assays with anti-St(a) and anti-Dantu sera identified the presence of St(a) glycophorin in four members of the family, two of whom were NOR+ and two NOR-.
Conclusion: Our results showed that two rare features of TS's RBCs, NOR polyagglutination and St(a) glycophorin, are inherited independently, and that NOR+ RBCs contain neutral glycolipids with an abnormal oligosaccharide structure, most likely terminated with alpha-galactosyl residues.