Researchers Find Two HIV Strains That Attack Immune System in ‘New Way’
Researchers have found two strains of HIV that "attack the immune system in a new way" and could alter existing HIV treatment, Reuters Health reports. Researchers led by Dr. Kunal Saha of the Ohio State University Medical Center report in the January issue of Nature Medicine that they found two strains of HIV that can "target" CD8+ cells. Previous studies show that HIV "largely affect[s]" CD4+ T cells, while CD8+ T cells were left "relatively untouched" by the virus. Researchers were able to isolate two strains of HIV from a single AIDS patient and found that both strains could invade and replicate "equally well" in both CD4+ and CD8+ cells. Although other studies had shown that HIV could infect non-CD4+ cells, this is the first to "isolate the virus and show the viral structure, to show that the viruses are different," Saha said. Researchers also found that neither of the two "most common" cell surface co-receptors used by the virus to enter the cells are required for infection of CD8+ cells, the "biggest surprise," Saha added. Because the findings are based on a sample from one patient, researchers do not know how common CD8+ infection may be. "If it's just a fluke that's one thing," Saha said, adding, "[I]f it's a common thing, that might explain the whole AIDS (disease process)." CD8+ cells play an "important role" in fighting HIV infection, according to Saha. He theorized that "under ... pressure from a declining pool of CD4+ cells in the body," the virus mutates and attacks CD8+ cells, causing immunity to decline and the onset of AIDS. If this is a "common occurrence," then treatment will need to be rethought to "prevent CD8-(infecting) HIV from appearing," he said (Agrawal, Reuters Health, 1/16).This is part of the KHN Morning Briefing, a summary of health policy coverage from major news organizations. Sign up for an email subscription.