Other so-called broadly neutralizing antibodies, immune system cells that stave off infection, have been isolated from HIV-positive patients in the past. But the newly discovered antibodies are not only much more effective, they work against scores of different strains of the virus found in various continents around the world.
"We looked at 162 different [HIV] viruses, and these antibodies neutralized 120 to 130 of strains from all across the world," Dennis Burton of Scripps, the lead author of the study, told Time magazine. The researchers collected blood samples from more than 1,800 people in Thailand, Australia and Africa who had been infected with HIV for at least three years without the infection progressing to full-blown AIDS. These individuals are most likely to produce antibodies that interfere with the replication of the virus. The researchers eventually isolated two antibodies, called PG9 and PG16, from one African patient. The antibodies could potentially be used to treat HIV-positive patients who develop severe disease. But more than that, researchers hope to find molecules that can stimulate the body to produce these antibodies. These molecules could be the main building block for a vaccine that would protect against HIV.