Researchers at the University of Minnesota have identified a compound that, when applied vaginally in monkeys, can prevent transmission of the primate version of HIV, called simian immunodeficiency virus, or SIV.
Department of Microbiology investigators Ashley Haase, Ph.D., and Pat Schlievert, Ph.D., found that glycerol monolaurate (GML), a naturally occurring compound the FDA recognizes as safe, prevented SIV infection in monkeys that were exposed to large doses of the virus. The inexpensive compound is widely used as an antimicrobial and anti-inflammatory agent in food and cosmetics.
Although GML is not a cure and still must go through human clinical trials before it’s used to protect against HIV, the research is a step toward preventing the devastating disease, which affects 33 million people worldwide.
Schlievert began using GML in 1992 to combat toxic shock syndrome, a potentially lethal bacterial infection. More recently, research has shown that GML acts against a variety of toxins and microbes and inhibits cytokines and chemokines, small molecules that play key roles in triggering the body’s defense system.
The researchers found that following sexual exposure to SIV, the primates’ natural defense system is activated, rushing immune cells (T-cells) to the site of infection. The virus uses these T-cells as fuel to expand infection locally and spread it throughout the body.
Since it was the defense system the researchers wanted to inhibit, it made sense to see whether GML might prevent transmission, Haase explains.
During the study, researchers applied GML to five monkeys; five other monkeys were left untreated as a control group. By the end of the study, four of five monkeys in the control group had contracted SIV, while none of the five in the GML-treated group showed any evidence of acute infection after receiving as many as four large doses of the virus.
The researchers believe GML has the potential to effectively prevent transmission of HIV to women, who account for close to 60 percent of new infections at the pandemic’s center in sub-Saharan Africa.
“After 25 years, an effective vaccine for HIV is still on the distant horizon, so … all research into ways to prevent the continued spread of this lethal virus remain critically important,” Haase says. “If GML as a topical microbicide can add to our prevention, it could contribute to saving millions of lives.”