(PHILADELPHIA) Tiny pieces of genetic material called microRNA (miRNA), better known for its roles in cancer, could be a key to unlocking the secrets of how HIV, the AIDS virus, evades detection, hiding in the immune system. Researchers at Jefferson Medical College in Philadelphia have shown that when an individual infected with HIV receives a powerful cocktail of antiviral agents called HAART (highly active antiretroviral therapy), the virus calls on miRNAs to help it remain quiet and practically undetectable, temporarily shutting down its ability to replicate and infect.