A treasure trove of 576 antibodies that bind to and neutralize HIV has been discovered in four infected individuals, vastly expanding the number of antibodies known to inactivate a broad range of HIV strains. Such molecules could be useful in treating, or even preventing, HIV infection.

Only a handful of broadly neutralizing antibodies against HIV had previously been isolated, partly because the molecules mutate so often. So Michel Nussenzweig at the Rockefeller University in New York and his colleagues devised a new way to fish out the antibodies — by targeting an area of the molecules not prone to frequent mutation.

They found that the antibodies bind to gp120, an HIV surface protein that the virus uses to enter host cells. A subset of the antibodies neutralized 96% of 118 viruses in a test panel. Although the antibodies were highly mutated, they all shared a sequence of 68 amino acids.

Science doi:10.1126/science.1207227 (2011)