Alphavirus Particle-Based Vaccine Vectors

Abstract

Most of the vaccines in use today are live attenuated, killed, or protein subunit vaccines. Although these vaccines have saved countless lives, there is still a need to develop safer and more efficacious ones. These improved new generation vaccines will enable us to protect more people from a greater number of different infectious disease threats. One such new vaccine technology is derived from the alphaviruses, which are single-strand, positive-sense RNA viruses in the family Togaviridae. By removing the genes that encode for the viral coat proteins, and replacing them with an antigen-encoding gene, these viruses become a replicon that can replicate its genome but cannot propagate new virus particles. The resources that the virus once expended to make new progeny are now diverted to making vaccine antigen within the host. As a result of this molecular alteration, the alphavirus particle-based vectors serve as an attractive technology for the development of new and improved vaccines.