Some Women Show Ability to Block HIV Infection
Three studies investigating uninfected wives of HIV-positive men found that some women possess the ability to ward off HIV infection, Newsday reports. The studies indicated that an "as-yet-unidentified protein" is protecting these women, who have engaged in unprotected sex with their HIV-positive husbands for several years. Two studies were performed in England -- one by Oxford University and the other by London's Imperial College -- and the third was conducted in Thailand by Chiang Mai University in collaboration with the CDC. Newsday reports that although the three studies were carried out separately, "their conclusions were remarkably similar." In all three studies, none of the wives carried the delta-32 gene, a "rare mutation that protects about 1% of humans" from HIV infection; and none exhibited any "known protective antibodies" at "atypical levels." The three groups all found elevated levels of CD8 white blood cells among "HIV-resistant" women. The Thai study also found a "soluble suppressive factor" in study subjects' blood that was shown to inhibit viral growth in test tubes. Dr. Ann Duerr of the CDC said "this mysterious factor" was found to be secreted by macrophages (large cells that engulf and absorb foreign bodies). Thus, these women were found to have a two-pronged immune response fighting off infection: elevated CD8 cells and macrophages that "excrete some chemical that blocks the viruses' ability to reproduce." The British and Thai researchers "hope to isolate the protective chemical, analyze it and determine whether it might offer clues for effective HIV treatment or vaccination," Newsday reports (Garrett, Newsday, 2/7).This is part of the Morning Briefing, a summary of health policy coverage from major news organizations. Sign up for an email subscription.