One of the key roadblocks to a cure for HIV infection and AIDS is the fact that the virus can “hide out” in a dormant state in immune system cells, evading treatment.
However, research in monkeys suggests that a new approach might push these hidden cells out of hiding, to where they can be destroyed by conventional antiretroviral drug therapy [ART].
The finding would need to be replicated in people, and many animal studies don’t pan out in humans.
Still, the research team from Emory University in Atlanta believes the therapy might some day “effectively diminish [the] HIV reservoir under ART as a means to establish a functional cure.”
The findings were presented Thursday at the annual Conference on Retroviruses and Opportunistic Infections in Boston. Experts note that research presented at medical meetings is typically considered preliminary until published in a peer-reviewed journal.
As the Emory team explained, conventional HIV treatment can greatly diminish the number of infected cells, but not eliminate all of them. That means there is still no cure for HIV infection, since the virus can make a comeback once therapy is stopped.
Finding hidden HIV-infected cells is key to eliminating the virus. The new strategy uses a specially developed antibody to block a molecule called PD-1.
According to the Emory researchers, PD-1 works naturally in the body to curb the immune system’s otherwise powerful response to chronic infections. That activity can be counterproductive, of course, when it comes to efforts to attack HIV.
Researchers led by Rama Rao Amara, a professor of microbiology, tested the approach in monkeys infected with simian immunodeficiency virus (SIV), the primate equivalent of HIV.
Some of the monkeys received the anti-PD-21 treatment two weeks before they were given traditional antiretroviral medicines. In that trial, levels of SIV began to rapidly fall in just 42 days, compared to 140 days in the monkeys who didn’t get the new treatment.
Other monkeys got the anti-PD-1 therapy in three infusions, with a month between each infusion. That approach brought SIV levels to very low levels, and any reappearance of the virus was short-lived, Amara’s team said.
The Emory group believes the therapy helps minimize hidden reservoirs of SIV, and might potentially do the same for HIV in humans — “destabilizing the viral reservoir” that persists despite traditional treatments.
The U.S. Centers for Disease Control and Prevention has more about HIV/AIDS.