Give Me a “G”

Researchers at the University of Iowa are considering a radical study into HIV disease treatment'deliberately infecting HIV-positive patients with an ancient strain of hepatitis in hopes of slowing HIV disease progression. Jack Stapleton, director of the university's Helen C. Levitt Center for Viral Pathogenesis, and his colleagues have been studying the harmless hepatitis G virus, also known as GBV-C, since the mid 1990s. They have discovered that the virus, which can be traced back to the earliest humans, decreases the prevalence of CCR5 receptors on the surface of immune system cells, portals that HIV uses to enter CD4 cells. A university study of 362 HIV-positive patients from 1988 to 1999 showed that those also infected with GBV-C were significantly less likely to die of AIDS-related complications (28.5% of those coinfected died during the course of the study, compared with 56.4% of study subjects infected with only HIV). A similar National Institute of Allergy and Infectious Diseases study produced comparable results. Stapleton's team has also discovered that infection with GBV-C boosted the body's production of chemokines, glycoproteins that have anti-HIV properties. While the decision has not yet been made to deliberately infect HIV-positive people with the hepatitis G virus, Stapleton is interested in studying how introducing the virus may affect HIV disease progression and possibly delay the onset of AIDS. 'I think it may be well-controlled in a closed setting,' he says, noting that an ideal study group would be HIV-positive patients no longer responding to existing anti-HIV treatments.