The use of radio-immuno-inhibition assay for the study of the y, d and w determinants of hepatitis B surface antigen.

A radioimmunoassay determination of the HBs antigen subtypes is discussed, it is simple but effective technique was used in association with the use of the Austria II kit (Abbott Laboratories). This method consists of an inhibition reaction of the Austria II test, by previous incubation of the antigen to be subtyped with a monospecific antibody. With this method we were able to distinguish the y and the d antigens as well as the w1, w3, w4 determinants of hepatitis B surface antigen.