Further Progress Toward AIDS Vaccine:experiments shows Rabies-Virus Vaccine Protects Monkeys

Thomas Jefferson University Researchers are one step closer to developing a vaccine against the AIDS disease. Director of the Jefferson Vaccine Cente, Matthias J. Schnell, Ph.D., and researchers found that a rabies virus-based vaccine administered to monkeys can protect against the simian equivalent of the HIV virus (SIV).

The researchers previously showed that a rabies-based vaccine expressing HIV and SIV antigens could be protective against a chimeric HIV/SIV virus in monkeys. In this study, researcher used highly attenuated rabies virus vaccine vectors to protect against challenge with the highly pathogenic SIVmac251.

Two vaccine strategies were used: first immunization with a recombinant rabies virus expressing SIVmac239GagPol, or a combination of that and a rabies virus expressing SIVmac239Env. Both strategies induced neutralizing antibody production, CD8+ T cell responses, and increased protection. Though the combination with Env helped immediately following the infection, but the long-term benefits were minimal. However, it was quite surprising to see that the rabies-based vaccine was able to induce such potent anti-SIV humoral responses.

Dr. Schnell said “Although we can’t yet block the infection, we showed that we can protect against disease,” He further said “We also saw significant antibody activity against the virus, which is promising. In addition, this is a very simple approach that only took two immunizations.”