Rearrangement of the genes of vesicular stomatitis virus eliminates clinical disease in the natural host: new strategy for vaccine development.

Gene expression among the nonsegmented negative-strand RNA viruses is controlled by distance from the single transcriptional promoter, so the phenotypes of these viruses can be systematically manipulated by gene rearrangement. We examined the potential of gene rearrangement as a means to develop live attenuated vaccine candidates against Vesicular stomatitis virus (VSV) in domestic swine, a natural host for this virus. The results showed that moving the nucleocapsid protein gene away from the single transcriptional promoter attenuated and ultimately eliminated the potential of the virus to cause disease. Combining this change with relocation of the surface glycoprotein gene yielded a vaccine that protected against challenge with wild-type VSV. By incremental manipulation of viral properties, gene rearrangement provides a new approach to generating live attenuated vaccines against this class of virus.