ABH blood group antigens in N-glycan of human glycophorin A.
We previously showed that a small proportion of the O-linked oligosaccharide chains of human glycophorin A (GPA) contains blood group A, B or H antigens, relevant to the ABO phenotype of the donor. The structures of these minor O-glycans have been established (Podbielska et al. (2004) [20]). By the use of immunochemical methods we obtained results indicating that ABH blood group epitopes are also present in N-glycan of human GPA (Podbielska and Krotkiewski (2000) [22]). In the present paper we report a detailed analysis of GPA N-glycans using nanoflow electrospray ionization tandem mass spectrometry. N-glycans containing A-, B- and H-related sequences were identified in GPA preparations obtained from erythrocytes of blood group A, B and O donors, respectively. The ABH blood group epitopes are present on one antenna of the N-glycan, whereas a known sialylated sequence NeuAcalpha2-6Galbeta1-4GlcNAc- occurs on the other antenna and other details are in agreement with the known major structure of the GPA N-glycan. In the bulk of the biantennary sialylated N-glycans released from GPA preparations, the blood group ABH epitopes-containing N-glycans, similarly O-glycans, constituted only a minor part. The amount relative to other N-glycans was estimated to 2-6% of blood group H epitope-containing glycans released from GPA-O preparations and 1-2% of blood group A and B epitope-containing glycans, released from GPA-A and GPA-B, respectively.
Fredriksson
Sten-Ake
SA
Swedish Defence Research Agency, Division of CBRN Defence and Security, SE-901 82 Umeå, Sweden.
Podbielska
Maria
M
Nilsson
Bo
B
Krotkiewska
Bozena
B
Lisowska
Elwira
E
Krotkiewski
Hubert
H
D000017:ABO Blood-Group System / Q000737:chemistry*; D000939:Epitopes / Q000737:chemistry*; D006021:Glycophorins / Q000737:chemistry*; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods; D009844:Oligosaccharides / Q000737:chemistry*
D000017:ABO Blood-Group System; D000939:Epitopes; D006021:Glycophorins; D009844:Oligosaccharides