Direct extraction of A and B blood group antigens from human red cells by liposomes.

Abstract

Some of the major blood group antigens are on lipids and proteins of the red cell membrane. Incubation of intact red cells with liposomes containing specially designed artificial lipids has been shown to result in the extraction of membrane proteins by the liposomes. The extraction of blood group structures and the retention of their antigenicity have not been reported. After the incubation of red cells with liposomes, the extraction of the antigens from human red cells by liposomes was examined by evaluation of the agglutination of the liposomes by respective antisera. Agglutination specific to the A and B blood group antigens was seen, which indicated that the antigenicity of the blood group antigens was retained even after the extraction by the liposomes. The presence of an artificial boundary lipid, 1,2-dimyristamido-1,2-deoxyphosphatidylcholine, in the liposome was crucial to the efficient extraction of the A and B antigens. On the other hand, the extraction of D, M, N, and P1 was not always detectable by agglutination. The A and B blood group antigens were directly extracted from red cells by liposomes without loss of antigenicity.