Immune response induced by a linear DNA vector: influence of dose, formulation and route of injection.

Previously, minimalistic, immunogenetically defined gene expression (MIDGE) vectors were developed as effective and sophisticated carriers for DNA vaccination. Here we evaluate the influence of dose, formulation and delivery route on the immune response after vaccination with MIDGE-Th1 vectors encoding hepatitis B virus surface antigen (HBsAg). An HBsAg-specific IgG1 and IgG2a antibody response was induced in a dose-dependent manner, whereas the IgG2a/IgG1 ratio was independent of the injected DNA dose.