MTOR Kinase is a Therapeutic Target for Respiratory Syncytial Virus and Coronaviruses

Therapeutic interventions targeting viral infections remain a significant challenge for both the medical and scientific communities. While specific antiviral agents have shown success as therapeutics, viral resistance inevitably develops making many of these approaches ineffective. This inescapable obstacle warrants alternative approaches, such as targeting host cellular factors. Respiratory syncytial virus (RSV), the major respiratory pathogen of infants and children worldwide, causes respiratory tract infection ranging from mild upper respiratory tract symptoms to severe life-threatening lower respiratory tract disease. Despite the fact that the molecular biology of the virus, which was originally discovered in 1956, is well described, there is no vaccine or effective antiviral treatment against RSV infection. Here, we demonstrate that targeting host factors, specifically, mTOR signaling, limits RSV protein production and viral replication. Further, we show that this approach is generalizable as inhibition of mTOR kinases reduces coronavirus gene expression, protein production and replication. Overall, defining virus replication-dependent host functions may be an effective means to combat viral infections, particular in the absence of antiviral drugs.