Biological Meaning of the Histo-Blood Group Antigens Composed of Sugar Chains / 대한수혈학회지

ABSTRACT

All living creatures on this planet, from bacteria to human, produce sugar chains (glycans). This means that sugar chains are essential for living a life. Abundant, diverse, and highly regulated repertoire of glycans are synthesized by glycosylation process in cells. Located in proteins (N-glycans and O-glycans) and lipids (glycosphingolipids), glycans participate in many vital biological processes including molecular recognition, cell adhesion, molecular trafficking and clearance, receptor activation, and signal transduction. Histo-blood group antigens that are composed of sugar chains are expressed under the control of the Secretor, Lewis and ABO glycosyltransferases. They play important roles in microbial infections and cancers. Many of sugar chains associated with histo-blood group antigens are exploited as receptors for microorganisms. Aberrant glycosylation of proteins and lipids occurs commonly during malignant transformation and leads to the expression of tumor-associated glycans. In this review, over the scope of transfusion medicine, we discussed deep down the biologic meaning of sugar chains, through exploring how the sugar chains are synthesized, structured, and functioning.