Das Antigen wird aus gentechnisch veränderten Hefezellen (Saccharomyces cerevisiae) gewonnen, die das für das wichtigste Oberflächenantigen des Hepatitis-B Virus (HBV) kodierende Gen tragen. ###>The antigen is produced by culture of genetically-engineered yeast cells (Saccharomyces cerevisiae) which carry the gene which codes for the major surface antigen of the hepatitis B virus (HBV).