A new vaccine appears to have “completely cleared” the monkey equivalent of HIV from half the primate subjects. Researchers they can use their findings to create a vaccine that does the same in humans.
A promising HIV vaccine developed by researchers at Oregon Health & Science University eradicated the virus that causes AIDS in monkeys, and scientists hope something similar can soon be tested on humans.
AIDS in non-human primates is caused by simian immunodeficiency virus, or SIV, which is similar to HIV but up to 100 times more deadly, BBC News reported. The research showed that half of the monkeys given the vaccine responded to it and were “completely clear” of SIV.
The researchers created the vaccine from a modified version of a common virus called cytomegalovirus (CMV). They said it prompted the monkeys’ white blood cells to seek out and destroy the SIV-infected cells.
“Through this method we were able to teach the monkey’s body to better ‘prepare its defenses’ to combat the disease,” Louis Picker, associate director of the OHSU Vaccine and Gene Therapy Institute, said in a press release.
The team tried the vaccine on 16 rhesus macaque monkeys and then infected them with SIV about two months later. Seven of the monkeys didn’t make it. In the other nine, the virus started to take hold before the vaccine kicked in.
Eight of the monkeys showed no sign of infection after a year and remained SIV-free three years later. Low levels of the virus did reappear in one of the monkeys, researchers said.
The team then injected blood and lymph cells from the eight apparently cured rhesus macaques into other monkeys. They said none of those monkeys became infected.
Researchers are now investigating why the vaccine only worked on a portion of the monkeys. They also want to see if it will be effective in humans.
“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,” Picker said.
The results were published online by the journal Nature and will later appear in print.