Viral Jujitsu: A New Gene Therapy Has a Way of Turning the AIDS Virus Against Itself

The war against AIDS is one of attrition. Antiretroviral drugs can slow the proliferation of the human immunodeficiency virus, delaying the day when the patient experiences full-blown AIDS. But they do not eliminate the virus, which can revive lethally after lying dormant for decades. Now an experimental gene therapy has emerged that may come a little closer toward actually curing AIDS. It works by turning HIV's own virulence against itself. The new therapy, produced by the small biotech firm Virxsys of Gaithersburg, Md., embeds a genetically engineered weapon called a lentiviral vector in the body's own disease-fighting T cells. (A vector is something that transfers genetic material into a cell; in this case it is a defanged version of HIV itself.) …