Researchers yesterday announced that they have discovered antibodies in a 60-year-old HIV+ Massachusetts man that can bond to as much as 90 percent of all HIV strains, thus allowing the body to attack the virus and turn back a potential infection. The key, as reported in the Wall Street Journal, is that the antibodies bond to a specific part of the virus’ outer shell that rarely mutates, solving one of the central and most vexing problems confronting vaccine researchers, as HIV viruses mutate faster than the body can keep up. By the time it has produced one set of antibodies, the virus may have changed completely, rendering these chemical tags useless to the immune system. Researchers say they are still exploring ways to exploit their discovery, and may experiment with directly injecting the antibodies into patients, or using them to “teach” a patient’s immune system to produce the same antibodies on its own.