Emory University virologist Harriet Robinson, working with colleagues at the National Institutes of Health, has developed an experimental AIDS vaccine that has begun human trials with volunteers at the University of California at San Francisco and the University of Alabama. The first trials will test the vaccine's safety and its ability to stimulate the immune system in healthy volunteers, while later trials will take place in high-risk groups, testing the vaccine's ability to prevent HIV infection or stop infection from developing into AIDS. The Emory vaccine uses DNA fragments that the body converts into proteins recognized by the immune system, and a booster shot of HIV proteins.