We have developed an enzyme-linked immunosorbent assay (ELISA) method for the detection of contaminating yeast components in the hepatitis B surface antigen (HBsAg) which was produced using yeast (Saccharomyces cerevisiae) by gene technology. This method could detect 1 ng/ml of the yeast component mixture. By using this method, we found that average remaining amounts of the yeast component mixture in specimens of recombinant HBsAg manufactured in an industrial real were not more than 0.52%, which was verified by the sodiumdodecylsulfate-polyacrylamide gel electrophoretic method. Next, we have developed an ELISA method for the assay of anti-yeast component antibody and analyzed changes of the antibody level in guinea-pig and human sera after vaccination with recombinant hapatitis B vaccine. Maximum doses given to guinea-pigs and humans were 100 and 20 μg per individual, respectively. As a result, anti-HBs antibody level in guinea-pig and human sera increased after vaccination, but no change was observed in anti-yeast component antibody level.
