Haemolysin test for characterization of immune ABO antibodies.

ABSTRACT

BACKGROUND & OBJECTIVES: Antibodies with haemolytic properties are common within the ABO system. These lytic antibodies are immunoglobulin G (IgG) and in high titres cause haemolysis during blood transfusion. Information on Immunoglobulin types and concentration of ABO haemolysins in Indian population is lacking. The present study was undertaken to know the usefulness of haemolysin test for characterization of immunoglobulin class of ABO antibodies. METHODS: Serum samples from 187 O group blood donors were screened for A and B haemolysins. Thirty five samples were treated with dithiothretiol (DTT) for characterization of Ig class. Antibody titre was compared with grade of haemolysis. RESULTS: Of the 51 strongly haemolytic serum samples, 32 (62.8%) had IgG titres of > or = 64 after treatment with DTT. There was significant association (P<0.05) between grade of haemolysin and anti B IgG titre. INTERPRETATION & CONCLUSION: Haemolysin test was found to be a useful screening test to identify group O donors with high levels of IgG anti A and/or anti B for blood transfusion purposes.