Anti-Di(b) as a red cell autoantibody.
BACKGROUND
It is known that some "warm"-reactive autoantibodies are directed against epitopes on the red cell anion exchanger, protein band 3. Some such antibodies (but not all) recognize Wrb. It is also known that Dia and Dib represent an amino acid polymorphism of band 3.


METHODS
Autoantibodies from 119 patients were tested against Di(b-) red cells. Seventy-four of these autoantibodies were subsequently absorbed with Di(b-) red cells.


RESULTS
All 119 autoantibodies initially reacted with the Di(b-) red cells, which showed that none contained only anti-Dib. Among the 74 adsorbed with Di(b-) red cells, two were found to contain an unadsorbed anti-Dib component.


CONCLUSIONS
No example of autoanti-Dib as the only autoantibody present was found among the 119 samples tested. However, 2 (2.7%) of 74 autoantibodies subjected to adsorption with Di(b-) red cells were seen to contain an anti-Dib component. This low incidence of autoanti-Dib is in marked contrast to the high incidence of autoanti-Wrb, although both antibodies define epitopes associated with the red cell anion exchanger, band 3.
Issitt
P D
PD
Transfusion Service, Duke University Medical Center, Durham, North Carolina, USA.
Combs
M R
MR
Allen
J
J
Melroy-Carawan
H
H
D000743:Anemia, Hemolytic / Q000276:immunology; D001457:Anion Exchange Protein 1, Erythrocyte / Q000276:immunology*; D001323:Autoantibodies / Q000032:analysis*; D001789:Blood Group Antigens / Q000276:immunology*; D004912:Erythrocytes / Q000276:immunology*; D006801:Humans
D001457:Anion Exchange Protein 1, Erythrocyte; D001323:Autoantibodies; D001789:Blood Group Antigens