Subunit protein vaccines: theoretical and practical considerations for HIV-1

With the spread of AIDS still rampant in many parts of the world, there is a global urgency to develop a vaccine against HIV-1. Without a doubt, developing an effective vaccine against the virus has been a monumental scientific challenge. Although advances in molecular biology and biotechnology over the years have enabled us to generate "designer antigens," our ability to transform them into successful vaccine candidates has been limiting. This review will be divided into three sections: First, the theoretical benefits and limitations of subunit protein vaccine strategy will be presented. Secondly, recent progress in our understanding of immune responses against AIDS vaccine candidates that incorporate recombinant proteins or peptides will be reviewed, mainly those that are designed to elicit humoral immune responses. Finally, some of the factors that must be considered in designing and evaluating future vaccine candidates will be discussed.