A Chink in the Armor

Renewing the hopes that scientists might eventually find a way to stop the HIV pandemic with a vaccine, researchers reported in the February 15 edition of the journal Nature that they had successfully mapped a location on HIV's surface that could make it especially vulnerable. A new 3-D map of the viral surface has allowed researchers at last to 'have revealed a gap in HIV's armor,' says National Institutes of Health director Elias Zerhouni. While HIV's uncanny ability to mutate has kept any vaccine candidate from attacking the virus successfully, some antibodies that vaccines cause the body to produce'called broadly neutralizing antibodies'seem to be unaffected by HIV's mutations. One such antibody, b12, was found to bind to an area of the viral surface that doesn't change. One of the unsolved mysteries of b12, says study coauthor Dennis Burton of the Scripps Research Institute, is why the human body doesn't readily produce it, especially since it attacks such a vulnerable site on HIV. But by studying and understanding the nature of the target on HIV, he says, researchers might be able to improve on nature.