Blood group antigens, structure

Fig. 2. Blood group antigens. Structure of the carbohydrate component of the Le glycoprotein of human blood. GIcNAc = JWacetyl-o-glucosaminyl GalNAc = Af-acetyl-o-galactosamlnyl Gal = D-galacto-syl Fuc = L-fucosyl.

Figure 25.12 Structures of the A, B, and 0 blood-group antigenic determinants.

It is now well established that the MN blood-group antigens are situated99-101 on the major sialoglycoprotein (glycophorin A) of the erythrocyte membrane. The complex, antigenic structure resides within the first five amino acid residues from the N-terminal portion of the molecule three of these residues are glycosylated. 

During blood transfusions, immune reactions can occur that destroy the erythrocytes transfused from the donor. These reactions result from the formation of antibodies (see p. 300) directed to certain surface structures on the erythrocytes. Known as blood group antigens, these are proteins or oligosaccharides that can differ from individual to individual. More than 20 different blood group systems are now known. The ABO system and the Rh system are of particular clinical importance. 

Zahler, P., Blood Group Antigens in Relation to Chemical and Structural... 

Fig. 10.4 Structures of the Lewis and blood group antigens expressed in H. pylori strains. See Moran (2008) for details. Abbreviations Fuc, fucose Gal, galactose GalNAc, IV-acetyl-galactosamine GlcNAc, A-acetyl-glucosamine Neu5Ac, A-acetyl-neuraminic (sialic) acid...

The structure of the blood group antigens is shown in Figure 10-15. In his paper (p. 314), Morgan listed several properties of the three antigens, A, B, and O, that were known at that time ... 

B, Imberty A. Crystal and molecular structure of a histo-blood group antigen involved in cell adhesion the Lewis x trisaccharide. Glycobiology 1996 6 537-542. 46. 

Geno- type Phenotype Blood group antigens on red cells (minimal determinant structure) Antibodies in plasma Giycosyitransferases in plasma... 

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