WHO collaborative evaluation of reference hepatitis B surface antigen and antibody reagents, subtype ad.

As a result of a WHO consultation in 1970 a guinea-pig antiserum, V801-501-058, was comprehensively evaluated by 11 collaborating laboratories in order to determine its usefulness as a reference reagent for the detection and assay of hepatitis B surface antigen (HB(s)Ag). The range of titres obtained were 1:64-1:256 by the immunodiffusion technique, 1:64-1:512 by counterimmunoelectrophoresis, 1:256-1:4096 by complement fixation, 1:6400-1:9600 by immune adherence haemagglutination, and <1:32 by platelet aggregation. The sensitivity of the guinea-pig antiserum for the detection of HB(s)Ag in serum and plasma samples was found to be equivalent to that of antisera obtained from other sources (man and baboon) with complement fixation and immune adherence haemagglutination, but it was slightly less sensitive with immunodiffusion and counterimmunoelectrophoresis. HB(s)Ag-positive reagent serum, which was used for the preparation of the immunogen, was found to have titres of 1:16-1:64 by immunodiffusion, 1:32-1:128 by counterimmunoelectrophoresis, 1:512-1:4096 by complement fixation, and 1:256-1:25 600 by immune adherence haemagglutination.