Gene transfer may lead to new HIV vaccine

PHILADELPHIA, May 20 (UPI) -- A U.S. research team says it may have broken the stubborn impasse that has frustrated the invention of an effective human immunodeficiency virus vaccine.

The scientists from the Children's Hospital of Philadelphia and the Nationwide Children's Hospital in Columbus, Ohio, said they used an approach that bypasses the usual path followed by vaccine developers.

By using gene transfer technology that produces molecules that block infection, the scientists said they successfully protected rhesus monkeys from infection by the simian immunodeficiency virus -- a virus closely related to HIV, which causes AIDS.

"We used a leapfrog strategy, bypassing the natural immune system response that was the target of all previous HIV and SIV vaccine candidates," said study leader Dr. Philip Johnson, chief scientific officer at the Philadelphia hospital. Johnson developed the novel approach with molecular virologist K. Reed Clark in Columbus.

Johnson cautioned many hurdles remain before the technique used in the animal research might be translated into an HIV vaccine for humans.

The study appears in the online version of the journal Nature Medicine.