Large scale purification of hepatitis B surface antigen (HBsAg)

In October 1975, a specific immunization by means of a formalin inactivated hepatitis B vaccine has been introduced to protect patients and staff members of three haemodialysis units of the Loire Valley (Tours, Blois, Orléans). After two years follow-up the innocuity and efficacy of this preparation have been shown to be very satisfactory in the conditions under which it was used. A method of vaccine preparation has been instituted in the development of industrial batches of vaccine to be used for broad clinical trials in France. The HBsAg purification was carried out by four different steps including, successively, selective adsorption-desorption on colloidal silicate (Aerosil), precipitations by polyethylene glycol, gel filtration and finally zonal ultracentrifugation. Step-by-step results of the purification are presented. Up to 65 % of the starting antigen was recovered at the end of the purification process. One dose of vaccine (1 ml) has a titre in HBsAg of 1/4 in countercurrent electrophoresis and a protein amount of 2-10 micron/ml. It contains traces of homologous serum proteins only detectable after high concentration. Purity, antigenic quality and safety of the vaccine are analysed in regards to its use for immunization against hepatitis B in man.