Scientists at the Johns Hopkins Bloomberg School of Public Health and their colleagues have made a significant advance in understanding how to block the transmission of the AIDS virus from one sexual partner to another.
They have developed a mouse model that allows them to identify and test agents that can stop the migration of white blood cells in semen or cervical mucus that are carrying the human immunodeficiency virus (HIV) nested within them. Using this animal model, the authors have already identified one compound that blocks this type of HIV transmission. The study appears in the January 2002 issue of the Journal of Clinical Investigation.
HIV is transmitted between sexual partners in two principal ways. First, by the "naked" virus itself when it enters the body of an uninfected sexual partner during intercourse. Until now, most efforts to prevent HIV transmission have focused on ways of killing naked, cell-free HIV, which, for example, can be eliminated by the antibodies generated by vaccines.
A second, less well known mode of transmission is by cell-associated viruses, viruses that hide inside normal white blood cells and are carried "Trojan horse-style" into the body. These cell-associated viruses may not be blocked by a vaccine that targets the naked virus.
First author Kristen Khanna, PhD, a research associate in the Department of Molecular Microbiology and Immunology at the Johns Hopkins Bloomberg School of Public Health, notes, "While considerable effort has been directed toward the identification of intervention strategies such as vaccines directed against cell-free viruses, there has been little effort to identify strategies for interrupting the migration of cells that are infected with HIV. We know that such infected cells are present in semen and vaginal secretions of infected individuals and many studies suggest that cell-associated transmission of HIV may, in fact, be more efficient that transmission of cell-free vi
Contact: Tim Parsons or Ming Tai
Johns Hopkins University Bloomberg School of Public Health