Structural characterization of x2 glycosphingolipid, its extended form, and its sialosyl derivatives: accumulation associated with the rare blood group p phenotype

Biochemistry. 1992 Jul 21;31(28):6509-17. doi: 10.1021/bi00143a022.


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].

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • ABO Blood-Group System
  • Antibodies, Monoclonal / immunology
  • Blood Group Antigens / chemistry*
  • Carbohydrate Sequence
  • Chromatography, Thin Layer
  • Epitopes
  • Erythrocytes / chemistry
  • Glycolipids / chemistry*
  • Glycosphingolipids / chemistry*
  • Humans
  • Mass Spectrometry
  • Molecular Sequence Data
  • P Blood-Group System / chemistry*
  • Tissue Distribution


  • ABO Blood-Group System
  • Antibodies, Monoclonal
  • Blood Group Antigens
  • Epitopes
  • Glycolipids
  • Glycosphingolipids
  • P Blood-Group System
  • sialoglycolipids