"Effective methods for blocking the transmission of HIV are urgently needed," said Michael Lederman, M.D., Scott R. Inkley Professor of Medicine and director of the Case Western Reserve University/University Hospitals of Cleveland Center for AIDS Research, in Cleveland, Ohio, and lead author on the paper. "Our study focuses on a strategy for preventing transmission of HIV through the vagina. We have identified a potential target, a mechanism critical for the transmission at vaginal sites of infection, that may offer a simple strategy for preventing HIV transmission."
"The vast majority of HIV infections in the world are sexually transmitted, most commonly through heterosexual sex," Dr. Lederman said. "But there has been substantial debate as to how the virus actually gets into cells at these sites of transmission, called mucosal sites. HIV can use certain cell surface molecules such as CCR5 to gain entry into immune system cells called CD4. We knew that people with a mutation whose CD4 cells' surface lack CCR5 are almost completely protected from acquiring HIV infection."
"But HIV can also use other target molecules to get into other cells. Thus, there was some uncertainty as to how HIV was transmitted at mucosal sites and therefore which pathways needed to be blocked in order to prevent HIV transmission there. We decided to test the hypothesis that blocking CCR5 alone would be sufficient to protect rhesus macaques from vaginal challenge with a virus like HIV. A natural immune messenger (chemokine) called RANTES can bind to CCR5 and by binding, forces the cell to internali
Contact: George Stamatis
American Medical Association