DIRECT EXTRACTION OF A-BLOOD-GROUP AND B-BLOOD-GROUP ANTIGENS FROM HUMAN RED-CELLS BY LIPOSOMES

Background: Some of the major blood group antigens are on lipids and p roteins of the red cell membrane. incubation of intact red cells with liposomes containing specially designed artificial lipids has been sho wn to result in the extraction of membrane proteins by the liposomes. The extraction of blood group structures and the retention of their an tigenicity have not been reported. Study Design and Methods: After the incubation of red cells with liposomes, the extraction of the antigen s from human red cells by liposomes was examined by evaluation of the agglutination of the liposomes by respective antisera. Results: Agglut ination specific to the A and B blood group antigens was seen, which i ndicated that the antigenicity of the blood group antigens was retaine d even after the extraction by the liposomes. The presence of an artif icial 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 P was no t always detectable by agglutination. Conclusion: The A and B blood gr oup antigens were directly extracted from red cells by liposomes witho ut loss of antigenicity.