Scientists at a U.S. university say they have found a cheap, commonly-used compound that blocks infection of the primate version of HIV. Researchers are hoping the compound could eventually be used on humans to fight transmission of the virus that causes AIDS.

In a new study, published Wednesday in the journal Nature, researchers tested a common compound called glycerol monolaurate, or GML.  The compound is already licensed as an antimicrobial and anti-inflammatory agent and is used in cosmetics and food products.

Researchers at the University of Minnesota tested GML on a group of monkeys, applying the microbicide to the female sexual organs of five of the primates. One hour later the monkeys were exposed to a large dose of SIV, the primate version of HIV.

None of the GML-treated group showed any acute infection, even after being exposed to the disease a second time.

Researcher Ashley Haase says GML breaks what he describes as a "vicious cycle" of immune-system signaling and inflammatory response that is triggered to exposure to the AIDS virus.

"And we found that GML could in fact prevent systemic infection of five of five animals of the treated animals whereas four of the five controls were infected. So, that's very good news, very exciting news," Haase said.

Haase says while it appears to offer some promise in preventing HIV infection in women, he cautions that a long road lies ahead before the microbicide can be verified as safe and effective for humans.

"Vaginal transmission of SIV to rhesus macaques is regarded by many as the best animal model for (human) vaginal transmission. But still it is an animal model. And so we certainly need further studies, and much longer term follow-up because we discovered at five months in one of the animals that had been apparently protected by GML was now positive for SIV," she said.

Sharon Hiller is principal investigator with the Microbicide Trials Network, which is funded by the U.S. government to conduct microbicide safety investigations worldwide.  

Hiller says this is the first time GML has been studied as a microbicide against HIV.

"This is really new research and I think provides the first convincing evidence that these simple kinds of molecules may in fact be very effective in blocking transmission," Hiller said.

If it is eventually approved for use by humans, researchers say GML could turn out to be a safe and effective topical cream or gel that women could use to keep them from becoming infected with the AIDS virus during sexual intercourse. Researchers say such a development could save millions of lives.

Around 33 million people around the world have HIV, two-thirds of them in sub-Sahara Africa. Globally, women make up 50% of all HIV-infected people, but in Africa, the number is nearly 60%.