Safety evaluation of a canine hepatitis DNA vaccine

DNA vaccines are a novel disease prevention methodology, however their safety has not been well described. We evaluated the safety and efficacy of the DNA vaccine pVAX1-CpG-Loop against infectious canine hepatitis. We demonstrated that pVAX1-CpG-Loop could not be recovered from tissues of vaccinated mice nor from F1 progeny and following vaccination there were no apparent changes in hematologic markers compared to unvaccinated controls. Most important, vaccinated mice were protected from viral challenge. The only detectable effects of the vaccination were elevated AST levels 4 weeks post vaccination and liver lymphocyte infiltration and hydropic degeneration which normalized 6 months later.