Gene delivery of vaccines for infectious disease.

Genetic immunization is the process of delivering and expressing a gene (or therapeutic nucleic acid) encoding a pathogen-derived antigen into target host cells to elicit a protective humoral or cell-mediated immune response. Gene delivery methods to achieve this goal have expanded rapidly, and currently employ a variety of oligonucleotides, synthetic polypeptides, recombinant vectors and even edible plants, all of which have been shown to be capable of inducing protective immunity in experimental animal models. This review highlights recent progress in several gene delivery systems (both non-viral and viral methods) using novel in vivo approaches to engender effective host immune responses against the introduced antigen.