Comparative immunogenicity of the Hepatitis B virus core 149 antigen displayed on the inner and outer membrane of bacterial ghosts

Two membrane compartments of Escherichia coli ghosts, representing empty bacterial cell envelopes, were investigated as carriers of foreign antigens. By subcutaneous immunisation of mice the immunogenicity of bacterial ghosts carrying the Hepatitis B virus core 149 protein (HBcAg-149) as model antigen anchored either in the inner or the outer membrane of E. coli was compared. Both systems induced significant immune responses against the foreign target antigen, the HBcAg-149, in mice. Results indicate that bacterial ghosts provide an excellent carrier system for antigen delivery.