Intralymphatic immunization enhances DNA vaccination

Although DNA vaccines have been shown to elicit potent immune responses in animal models, initial clinical trials in humans have been disappointing, h ighlighting a need to optimize their immunogenicity. Naked DNA vaccines are usually administered either i.m. or intradermally. The current study shows that immunization with naked DNA by direct injection into a peripheral lym ph node enhances immunogenicity by 100- to 1,000-fold, inducing strong and biologically relevant CD8+ cytotoxic T lymphocyte responses. Because inject ion directly into a lymph node is a rapid and easy procedure in humans, the se results have important clinical implications for DNA vaccination.