Scientists take lesson from immune system in hunt for HIV vaccine

A vaccine has been elusive in part because the AIDS virus mutates rapidly, making it a moving target for researchers. However, in a small fraction of people who have been infected for a couple of years, their immune systems learn to recognize the viral mutations, cranking out “broadly neutralizing antibodies” that naturally block HIV in its many disguises. Scientists have tried to harness the potential of these antibodies and translate that knowledge into a vaccine that could induce antibodies in humans to fight the ever-changing virus. Now, researchers in a large-scale collaboration at a number of institutions say they have taken a major — though early — step toward such a vaccine development. Experiments with the vaccine were successful in a mouse model that mimicked the human immune system. The achievement was described in five papers published simultaneously in the journals Cell, Immunity and Science. Frederick Alt, director of the Program in Cellular and Molecular Medicine...