CHAPEL HILL -- HIV, the virus that causes AIDS, may be adapted for use in gene therapy to treat genetic diseases and disorders of the immune system, even including AIDS, according to a scientist at the University of North Carolina at Chapel Hill.
New findings released June 24 in the journal Molecular Therapy provide the first evidence that a genetically stripped down amalgam of HIV components can not only safely deliver genes to target cells in the body but can be fashioned with a molecular switch system that turns them off in response to a common antibiotic.
This accomplishment was achieved without toxic affects in laboratory rats. However, it suggests that doctors may someday be able to control gene expression in people who are treated with gene therapy vectors based on HIV. With such control, genes can be switched off when no longer needed, say, for example, in the production of growth hormone. And if adverse affects develop, gene expression can be curtailed.
The new study was led by Tal Kafri, Ph.D., assistant professor of microbiology and immunology at UNC-CH School of Medicine. Kafri conducted the study while he was a postdoctoral scientist with Inder M. Verma, Ph.D. at the Salk Institute in La Jolla, California. In earlier experiments, Kafri and others had studied the potential feasibility of gene therapy viral vectors based on lentiviruses, a subfamily of retroviruses. HIV is a lentivirus.
"One advantage of HIV and other lentiviruses is that they can introduce the gene of interest into cells that do not divide. Simple retroviruses cannot do that" Kafri noted. "This makes them ideal for delivering genomic material directly into the body because most of our cells do not divide. This is very important for transducing (transferring genetic material to) hemopoietic stem cells (precursor blood cells) because most of them are quiescent and do not divide."