Use of a zwitterionic detergent for the preparation of an influenza virus vaccine: 2. Immunogenicity of Empigen-treated virus in animals.

The immunogenicity of zwitterionic detergent-disrupted influenza virus vaccine preparations, intact virus vaccine and vaccine preparations obtained by treatment of the intact virus with Triton-X 100 or cetyl trimethyl ammonium bromide (CTAB) was studied in hamsters and mice. In all experiments the intact, inactivated virus vaccine induced greater serum haemagglutination-inhibiting (HI) and neuraminidase-inhibiting (NI) antibody titres than the detergent-disrupted preparations. The serum HI antibody responses induced in hamsters and mice by Empigen-, Triton-, or CTAB-disrupted vaccines were similar, although more highly purified Empigen-disrupted preparations elicited marginally lower immune responses. In both animal species, all vaccine preparations afforded a similar degree of protection against homologous virus challenge.