Veterinary applications of DNA vaccines.

DNA immunization of livestock has proven to be more challenging than similar approaches in mice. To identify parameters, which could influence the magnitude and type of immune response generated by DNA immunization, we have assessed promoter strength, the role of introns, route of delivery as well as form of antigen. Our results indicate that all of these factors can have an impact on whether an immune response will occur or not, as well as influence the type of immune response generated. Finally we have demonstrated that DNA does have a significant effect on lymph node architecture, suggesting that the DNA does not remain exclusively at the site of injection.