Bacterial ghosts as carrier and targeting systems for mucosal antigen delivery.

The application of new strategies to develop effective vaccines is essential in modern medicine. The bacterial ghost system is a novel vaccine delivery system endowed with intrinsic adjuvant properties. Bacterial ghosts are nonliving Gram-negative bacterial cell envelopes devoid of cytoplasmic contents while maintaining their cellular morphology and native surface antigenic structures including bioadhesive properties. They are produced by PhiX174 protein E-mediated lysis of Gram-negative bacteria. The intrinsic adjuvant properties of bacterial ghost preparations enhance immune responses against envelope-bound antigens, including T-cell activation and mucosal immunity. Since native and foreign antigens can be expressed in the envelope complex of ghosts before E-mediated lysis, multiple antigens of various origin can be presented to the immune system simultaneously. In addition, the extended bacterial ghost system represents a platform technology for specific targeting of DNA-encoded antigens to primary ant...