Post-exposure DNA vaccination protects mice against rabies virus

Post-exposure anti-rabies vaccination for individuals who have not previous ly been immunized against rabies includes a cell culture-derived vaccine an d a one time injection of rabies immune globulin. Recent studies have shown DNA vaccinations to be highly effective in rabies pre-exposure experiments , but post-exposure protection has not been achieved. This failure is likel y due to the slow onset of DNA vaccine induced antibody production. In an a ttempt to accelerate the onset of the antibody response, we manipulated var iables, such as the route of vaccination and booster frequency. Anti-rabies virus antibody was detected 5 days after the initial DNA vaccination. Usin g this vaccination protocol and a single non-protective dose of anti-rabies immune serum, we questioned whether mice injected 6 h previously with rabi es virus would be protected if a DNA vaccine was substituted for the cell c ulture-derived human diploid cell vaccine (HDCV). The DNA vaccine protected 87% of the mice (P = 0.00005. compared with unvaccinated control mice). So me 75% of mice receiving HDCV were protected (P = 0.00097. compared with un vaccinated control mice). Mice receiving only anti-rabies immune serum were not protected (P > 0.05 compared to unvaccinated control mice). Thus, post -exposure therapy, substituting a DNA vaccine for HDCV, did not compromise protection against rabies virus. published by Elsevier Science Ltd.