Prime-Boost Strategies in DNA Vaccines

Induction of HIV-specific T-cell responses by vaccines may facilitate efficient control of HIV replication. Plasmid DNA vaccines and recombinant fowlpox virus (rFPV) vaccines are promising HIV-1 vaccine candidates, although delivering either vaccine alone may be insufficient to induce sufficient T-cell responses. A consecutive immunization strategy, known as “prime-boost,” involving priming with DNA and boosting with rFPV vaccines encoding multiple common HIV antigens, is used to induce broad and high-level T-cell immunity and ameliorate AIDS in macaques. This vaccine strategy is proceeding to clinical trials. This chapter describes the use of prime-boost vaccines to induce T-cell responses against HIV-1 and protective immunity against AIDS in macaques. Methods for the construction of the vaccines, the use of animal models, and the detection of immune responses are described.