A Clinical Case of Weak A Antigen on the Erythrocytes in a Person with Coexistent Anti-A Antibodies


V. Dielievska 1 , * , M. Korzh 2 , F. Leontieva 2 , N. Ashukina 2 , O. Borzova 1

1 Kharkiv National Medical University, Department of Internal Medicine № 2, Clinical Immunology and Allergology Named after Academician L.T. Malaya

2 National Academy of Medical Sciences of Ukraine SI & ldquo; Sytenko Institute of Spine and Joint Pathology & rdquo

How to Cite: Dielievska V, Korzh M, Leontieva F, Ashukina N, Borzova O. A Clinical Case of Weak A Antigen on the Erythrocytes in a Person with Coexistent Anti-A Antibodies, Arch Razi Inst. 2020 ; 75(2):e106959. doi: 10.22092/ari.2020.341761.1439.


Archives of Razi Institute: 75 (2); 257-265
Published Online: June 01, 2020
Article Type: Research Article
Received: June 28, 2020
Accepted: April 19, 2020


This study investigated a person with an AB0 discrepancy. Her blood group initially typed at the birth as AB Rh+ (positive); however, it was B Rh+ (positive) or Rh- (negative) when she was in her teens. At room temperature, her erythrocytes were agglutinated by anti-B, and the agglutination was significantly weaker at 37 ºC. As a result, her erythrocytes did not absorb anti-B but anti-A. Furthermore, her erythrocytes were agglutinated by anti-A at 37 ºC with signs of hemolysis in the presence of complement. The unwashed erythrocytes were also agglutinated in an antiglobulin test by polyclonal anti-A at 37 ºC and by heated polyclonal anti-A and anti-A MAB 2-8 at room temperature. Moreover, her serum agglutinated A erythrocytes at room temperature with less activity at 37 ºC; however, it agglutinated B erythrocytes at 37 ºC. The ability of the erythrocytes of this person to absorb anti-A came along with the agglutination of her erythrocytes at 37 ºC by polyclonal serum and decreased activity of the serum to agglutinate A erythrocytes at 37 ºC, compared to room temperature. The absence of anti-B absorbance by the person’s erythrocytes was accompanied by the presence of anti-B in the serum, which was active at 37 ºC. The incubation of the person’s serum with 0 erythrocytes induced the ability of erythrocytes to absorb anti-A and to be hemolyzed by anti-A in the presence of complement in accordance with the person’s characteristics of erythrocytes. The reaction of absorption and agglutination at room temperature and 37 ºC by heated serum with the use of complement may help to reveal both weak A and B antigens and anti-A and anti-B antibodies while AB0 blood typing.


© 2020, Author(s). Razi Vaccine and Serum Research Institute.