ABSTRACT
Despite the impact of vaccination programs, which have signicantly reduced the incidence and mortality of infectious diseases worldwide, there is still a great need to develop safer vaccination strategies that induce long-lasting immunity. Recent advances in genomics and proteomics have identied a wide variety of potential new vaccine modalities, including recombinant proteins and synthetic peptides. While these clearly dened antigens offer important safety advantages, they are not always processed and presented effectively by the immune system. For efcacy, the particle form of a pathogen seems of major importance. Indeed, vaccine delivery systems that mimic pathogen size, shape, and surface molecule organization appear advantageous for the induction of protective immune responses, notably neutralizing antibodies, as exemplied by inactivated or attenuated virus vaccines, or vaccine formulations with particles in the viral or bacterial size range [1,2]. For safety, as much as possible of the pathogen genome should be deleted to avoid potential reversion or too severe side effects. In short, a desirable vaccine design features most properties of a pathogen, with the exception of causing disease. Genome-free, virus-like particles (VLPs) meet these criteria. Various VLPs have demonstrated safe and efcient induction of humoral and cellular immune responses in animal studies [3], and clinical trials [4-8], and some have already been marketed. VLPs may therefore be a potent platform to induce specic immune responses against antigens of choice. Many different VLP types have been adapted for this purpose, as illustrated in this book.
