Studies on agglutinating antibodies of group O serum against weak subgroup red cells

Research Project

Project/Area Number	03670302
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Legal medicine
Research Institution	Kagoshima University
Principal Investigator	AGO Kazutoshi Kagoshima University, Medicine, Assistant Professors, 医学部, 講師 (20102056)
Project Period (FY)	1991 – 1992
Project Status	Completed (Fiscal Year 1992)
Budget Amount *help	¥1,700,000 (Direct Cost: ¥1,700,000) Fiscal Year 1992: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1991: ¥1,200,000 (Direct Cost: ¥1,200,000)
Keywords	Forensic serology / ABO blood group system / Group O serum / Cross-reacting antibody / Weak subgroup / Affinity chromatography / IgG antibody / 交叉反応性抗体 / アフイニテイクロマトグラフイー / 抗A,B抗体 / 変異型 / アフイニテイ精製
Research Abstract	The basic cause of superior agglutinating activities of group O serum against weak subgroup red cells was investigated. Blood group specific antibodies in group O, group A, and group B serum were fractionated by affinity chromatography with group A and group B specific immunoadsorbents. The antibody fractions obtained were tested for their strength against A_3B, Ax, Bm, and ABm cells, respectively. All of the anti-A, anti-B, and anti-A, B from group O serum were found to be highly effective agglutinators of weak subgroup cells in contrast to both of anti-A from group B and anti-B from group A serum. These findings suggest that anti-A, anti-B, and anti-A, B antibodies in group O serum take part in serological reactions leading to the agglutination of weak subgroup cells together. Furthermore, studies by the immunodiffusion method and the mercaptoethanol method revealed that all of the antibodies from group O serum were IgG antibodies, whereas those from group A and group B serum were IgM antibodies. Thus, it can be concluded that the superior agglutinating activities of group O serum against weak subgroup cells are attributed to IgG anti-A, IgG anti-B, and IgG anti-A, B antibodies present in the serum. Although the absorption test has been conducted with several kinds of synthetic origosaccharides (Synsorb) relevant to the ABO blood group system, whether the structures of group specific antigens recognized by the antibodies from group O serum differ from those by antibodies from group A and group B serum can not be decided at the present time.