Researchers are reporting that a new method for altering the genes of immune cells to make them resistant to HIV infection was a success in mice. The study was published online on July 2 in the journal Nature Biotechnology.

The new type of therapy, which treats stem cells with engineered zinc-finger nucleases, is designed to help the body grow new CD4 cells that don’t carry one of the key coreceptors—CCR5—that HIV requires to enter and infect a cell. In this experiment, Nathalia Holt, PhD, from the Keck School of Medicine at the University of Southern California at Los Angeles, and her colleagues compared two groups of mice that are bred to have a human immune system. The first group was given untreated stem cells. The second group received a batch of zinc-finger-treated cells.

Holt’s team found that the treated stem cells multiplied rapidly in the mice and were highly resistant to HIV infection. By comparison, the untreated cells did not spawn HIV-resistant cells, and the mice who receive the untreated cells experienced HIV-related CD4 cell losses, indicative of disease progression.

Sangamo BioSciences is developing this therapy, and small exploratory studies of zinc-finger therapy are already taking place in humans. For a snap shot of a meeting that the POZ and AIDSmeds staff had with Sangamo, click here.