PORTLAND — Researchers at Oregon Health & Science University are hopeful that an HIV/AIDS vaccine candidate that was successful in clearing simian immunodeficiency virus (SIV) will also eradicate HIV in humans, the school announced in a press release last week citing a study that was published in the journal Nature on Sept. 11.
“To date, HIV infection has only been cured in a very small number of highly publicized but unusual clinical cases in which HIV-infected individuals were treated with anti-viral medicines very early after the onset of infection or received a stem cell transplant to combat cancer,” Dr. Louis Picker, associate director of the Oregon Health and Science University Vaccine and Gene Therapy Institute, wrote in the press release.
“This latest research suggests that certain immune responses elicited by a new vaccine may also have the ability to completely remove HIV from the body.”
The researchers tested a vaccine for a specific kind of simian immunodeficiency virus (SIV) called SIVmac239 on 16 rhesus macaque monkeys. This version is up to 100 times more deadly than HIV and monkeys typically die within two years.
The vaccine used the cytomegalovirus (CMV), which is part of the herpes family. Researchers modified the virus’ natural ability to spread through the body, instead having it tell all the various parts of the immune system — particularly the T-cells that can fight off SIV infection — to target the SIV, the press release said.
All the monkeys were vaccinated and then exposed to SIVmac239. In nine of the cases, the monkeys’ immune systems were able to fight off infection and destroy the virus. Those monkeys remained infection free between one-and-a-half to three years later.
Researchers are still trying to determine why it worked in some of the monkeys but not others, according to the press release.
The researchers in the latest monkey study want to try the vaccine method on humans with HIV, but acknowledge that they still have to make sure it is safe. They hope the first human clinical trials can start within two years, the announcement said.