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Properties and relative immunogenicity of various preparations of recombinant DNA-derived hepatitis B surface antigen.

The gene for hepatitis B surface antigen was cloned into vectors for expression in yeast and mammalian cells. These hosts assemble the surface antigen protein into spherical structures containing cell-derived lipids. Particles were isolated from these cell cultures and purified by standard biochemical and biophysical means. Protein micells were formed from such particles by removal of lipid with nonionic detergent. Both particle and protein micellar preparations were formulated with alum adjuvant and tested for their immunopotency in mice. All the materials so analysed proved to be highly immunogenic. Safety and regulatory aspects of these materials and other potential and current hepatitis B vaccines are discussed. It is concluded that the yeast-derived materials and certain mammalian cell production systems present the most suitable opportunities for new hepatitis B vaccines.