According to a report in the journal Science, the antibodies have two major advantages: They are able to neutralize many strains of the HIV virus, and they target a more or less stable portion of the virus that researchers had previously not considered. This target does not experience the mutations that have traditionally made it difficult to develop an AIDS vaccine. The International AIDS Vaccine Initiative, which funded the research, says that HIV is the most mutation-prone pathogen ever seen by modern science.
Researchers took blood samples from more than 1,800 patients who had been infected with HIV for over three years without developing severe AIDS. Such people were more likely to have antibodies that could block or neutralize the HIV virus. Analysis was carried out by Monogram Biosciences and Theraclone Sciences. Researchers from Monogram studied the samples that were most resistant to infection. A team from Theraclone looked at antibodies from an African donor who had a particularly strong ability to resist infection. The team isolated two antibodies that blocked about 75 percent of the 162 HIV strains they were tested against.
It will still be a while before a vaccine is produced. Scientists hope to find molecules that can stimulate the body to produce the antibodies. The two antibodies could also be used to treat HIV-positive patients who develop severe AIDS.