Researchers for the first time reversed symptoms of HIV infection in a living animal using the technique of RNA interference. They constructed an antibody that targets T cells — in which HIV lurks — and linked it to a peptide carrying small RNA molecules, called siRNAs. The peptide helps these siRNAs enter T cells, where they silence certain host and virus genes crucial to the virus's replication.
Premlata Shankar, now at the Texas Tech University Health Sciences Center in El Paso, Sang-Kyung Lee of Hanyang University in Seoul, South Korea, and their colleagues injected the construct into mice genetically engineered to be easy to infect with HIV. The construct protected the mice from infection. It also restored the suppressed immune systems of mice that bore HIV-infected immune cells.