Number and distribution density of ABH and MN antigen sites on young and old human erythrocyte surfaces.

Abstract There were no differences in the number of A and M antigen sites between young and old human erythrocyte surfaces. No essential differences in the number of A 1 , N and Vicia graminea N antigen sites could be observed between young and old erythrocytes. The number of B and H antigen sites on cell surface was significantly higher in young erythrocytes than in old ones. The distribution density of A and M antigen sites on young erythrocyte was remarkably higher than that on old ones. Compared with young erythrocytes, significant increases in the distribution density of A 1 , B, H, N and Vicia graminea N antigen sites were observed in aged erythrocytes. It is suggested from these and other observations that human erythrocytes aging is accompanied by elimination of a small amount of B and H antigens from cell membranes, while A, A 1 , M, N and Vicia graminea N antigens are not released from cell membranes during in vivo aging.