Enhancement of DNA vaccine potency using conventional aluminum adjuvants

The immunogenicity and protective efficacy of DNA vaccines have been amply demonstrated in numerous animal models of infectious disease. However, the feasibility of DNA vaccines for human use is not yet known. Ln order to inv estigate potential means of increasing the potency of DNA vaccines, convent ional adjuvants such as aluminum salts were tested. Coadministration of the se adjuvants with DNA vaccines substantially enhanced the ability of these vaccines to induce antibody responses up to 100-fold in mice and guinea pig s, and 5-10-fold in non-human primates. Effective formulations had no demon strable effect on the levels of antigen expression in situ and consisted of adjuvants that did not form complexes with the plasmid DNA; rather they ex erted their effects on antigen after expression in situ. Therefore, the pot ency of DNA vaccines both in laboratory rodents and in non-human primates c an be substantially increased by simple formulation with conventional alumi num adjuvants. (C) 1999 Elsevier Science Ltd. All rights reserved.