RNA Interference Could Provide New Method for Fighting HIV, Researchers SayRNA interference -- an "ancient" process by which small interfering RNA breaks down messenger RNA, thereby disrupting the transfer of genetic material necessary for viral replication -- could hold promise for fighting HIV and other viruses, according to an article published in yesterday's edition of the New England Journal of Medicine, Reuters Health reports. In the article, Drs. Moiz Kitabwalla and Ruth Ruprecht of the Dana-Farber Cancer Institute state that as more Americans become infected with drug-resistant strains of HIV, there is even more need for "new strategies for targeting HIV." Among the strategies they suggest is RNA interference, a process long used by plants, worms and other "lower species" to ward off infections. Dr. Judy Lieberman of the Boston-based Center for Blood Research and colleagues first discovered about a year and a half ago that RNA interference could work in mammals. In a study published last summer, Lieberman and colleagues reported on how they used the process to "silence" messenger RNA, which holds the genetic material that instructs DNA on how to make proteins, in both immune cells and HIV. According to Kitabwalla and Ruprecht, two other research teams have also used RNA interference to fight HIV infection in laboratory tests.
Obstacles to Clinical Practice
Although the process holds promise for fighting HIV, there are several obstacles that must first be overcome before it can be tried in humans, according to the authors. They note that transferring small interfering RNA, or siRNA, into cells is an "inefficient process" and that researchers must devise ways to ensure that the siRNA remains stable once inside the cell. If researchers can harness RNA interference, they may be able to target viruses other than HIV and "mutant" genes in cancer cells, Kitabwalla and Ruprecht report. Lieberman noted that although RNA interference research is a "fast-moving field," therapies using the process are still "many years from clinical practice" (McKinney, Reuters Health, 10/24).