Functions of blood group antigens
This chapter reviews knowledge about erythrocyte membrane proteins that bear blood group antigens and whose functional importance has been characterized. It focuses on two of the most interesting of these proteins: the anion exchanger protein, which bears antigens of the Diego blood group system, and the Rh proteins. The chapter briefly summarizes functional information about other proteins. Glycophorins C and D (GPC/GPD) are 32 and 23 kDa membrane glycoproteins arising from the same four-exon gene via alternative in-frame mRNA translation initiation sites, giving rise to the Gerbich erythrocyte antigens. A number of erythrocyte membrane proteins have been identified as adhesion molecules. CD44 was the first erythrocyte membrane protein to be characterized as an adhesion molecule and bears homology to the cartilage link and proteoglycan core proteins, which are known to interact with hyaluronan.
