Structural characterization of x2 glycosphingolipid, its extended form, and its sialosyl derivatives: accumulation associated with the rare blood group p phenotype.
It has been suggested that the x2 glycosphingolipid (GSL) could offer a structural basis for a P-like antigen activity found in blood group p individuals [Kannagi R., Fukuda, M.N., Hakomori, S. (1982) J. Biol. Chem. 257, 4438]. The structures of the x2 and sialosyl-x2 GSLs have been confirmed unequivocally as shown below by +FAB-MS, methylation analysis by GC-MS, and 1H-NMR. We have established a [formula: see text] monoclonal antibody (TH2) specific for the GalNAc beta 1----3Gal beta 1----4GlcNAc epitope, the terminal trisaccharide of x2 GSL. Application of MAb TH2 on TLC immunoblotting together with chemical analysis indicates the following points of interest: (i) the existence of extended type GSLs having the same x2 terminal structure; (ii) the chemical quantities of x2, sialosyl-x2, and extended x2 found in blood cells and in various tissues including carcinomas being nearly the same; (iii) considerably larger quantities of x2 and x2-derived structures found in blood samples of rare blood group p individuals. The accumulation of x2 and its derivatives in blood cells of p individuals is in contrast to the occurrence of these GSLs as extreme minor components in normal human red blood cells and tissues, and they may be responsible for the reported P-like activity in blood group p individuals [Naiki, M., & Marcus, D. M. (1977) J. Immunol. 119, 537].
Thorn
J J
JJ
Biomembrane Institute, Seattle, Washington 98199.
Levery
S B
SB
Salyan
M E
ME
Stroud
M R
MR
Cedergren
B
B
Nilsson
B
B
Hakomori
S
S
Clausen
H
H
D000017:ABO Blood-Group System; D000911:Antibodies, Monoclonal / Q000276:immunology; D001789:Blood Group Antigens / Q000737:chemistry*; D002240:Carbohydrate Sequence; D002855:Chromatography, Thin Layer; D000939:Epitopes; D004912:Erythrocytes / Q000737:chemistry; D006017:Glycolipids / Q000737:chemistry*; D006028:Glycosphingolipids / Q000737:chemistry*; D006801:Humans; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010127:P Blood-Group System / Q000737:chemistry*; D014018:Tissue Distribution
D000017:ABO Blood-Group System; D000911:Antibodies, Monoclonal; D001789:Blood Group Antigens; D000939:Epitopes; D006017:Glycolipids; D006028:Glycosphingolipids; D010127:P Blood-Group System; C009255:sialoglycolipids