Nano-Particulate Platforms for Vaccine Delivery to Enhance Antigen-Specific CD8+ T-Cell Response.

Abstract

Vaccines remain the most effective way to protect populations against deathly infectious diseases. Several disadvantages associated with the traditional vaccines that use whole pathogens have led to the development of alternative strategies including the useofrecombinant subunit vaccines. Subunit vaccines are, in general, safer than whole pathogens but tend to be less immunogenic due to thelackofmolecular cuesthat are typically found on whole pathogens.To enhance immunogenicity, the subunit antigen can be administeredwith adjuvants that stimulate the innate immune system as a means to steer the quality andmagnitude of the adaptive immune response. Novel classes of adjuvants are formulatedusing particle-based platformssuch as virus-like particles, liposomes, and polymeric nanoparticles. These particle-based systemspresent antigens in ways reminiscent of wholepathogens. Such platforms offer several advantages that include co-delivery of antigen along with innate immune stimulators in ahighly immunogenic format. Here we describe our recent efforts to synthesize, characterize, and validate two promising nanoparticle-based delivery systems anddemonstrate their potential to induce antigen-specific CD8+ T cell responses, essential in clearing infectionwith intracellular pathogens, such as viruses and bacteria, and eradicating tumors.