Biotinylation: A nonradioactive method for labeling of blood components

The purpose of this review is to summarize articles about biotin labeling o f blood components. Biotin (vitamin H) is present in plasma and serves as a coenzyme for several intracellular carboxylase enzymes of intermediary met abolism, Biotin is not normally found on the cell surface, biotin labeling is stable in vivo and does not affect cell survival. This labeling techniqu e of erythrocytes was performed in animals and also in humans; it allows th e determination of red-cell volume and red-cell survival without radioactiv ity and thus is applicable in children and pregnant women. Transfusion of b iotinylated platelets to animals and humans did not cause any adverse event s, even when healthy volunteers were rechallenged by transfusion of biotiny lated platelets. Negative effects of biotinylated cells have been minimal i n vivo, and one of the great advantages of this labeling technique is its l ow toxicity. However, further studies will require close attention to possi ble immunological consequences.