Scientists have successfully modified genes in the blood cells of HIV-positive people to help make them resistant to the virus. The radical therapy — never before tested on humans — raises hope that such an approach might one day free people living with HIV from their daily, lifelong drug regimen.
The inspiration for the gene modification treatment came from the ‘Berlin patient’ who appears to be clear of the virus following stem-cell transplants in 2007/2008 from a donor with a natural immunity to HIV.
Only 1% of the population is naturally resistant to HIV. These people lack the CCR5 protein that the virus latches on to in order to unlock blood cells and infect them. Researchers have been seeking to mimic the rare mutation that makes some people HIV resistant by engineering a gene in people’s blood T-cells.
Twelve people participated in the American study, half of whom were taken off HIV treatment to see if the cellular engineering had any effect. Although the virus returned in all but one of them, the edited immune cells appeared to keep the virus at bay — more so than the body’s natural immune cells. All of the participants in the study are now back on treatment.
While only a small-scale trial, Bruce Levine, who co-led the study at the University of Pennsylvania, described the early
results as encouraging: “This is potentially a new therapy for HIV. ‘Cure’ is a four-letter word. We don’t like to use it, particularly with HIV. We are looking at improving the health and immune function of PLHIV.
BY CHRISTOPHER KELLY