Microparticles from human lower airway showed inhibitory activity against respiratory syncytial virus

Abstract Airway microparticles (MPs) have been previously shown to inhibit influenza virus by trapping virions on their surface through surface viral receptor. It was hypothesized that airway MPs may carry most of epithelial cell surface molecules including receptors for respiratory viruses and may be able to inhibit various respiratory viruses. We show here that MPs from human bronchoalveolar lavage (BAL) could inhibit respiratory syncytial virus (RSV). Those MPs were stained positive for the RSV receptor, CX3CR1. Furthermore, incubating the MPs with a monoclonal antibody against CX3CR1 reduced the anti-RSV activity. These indicate that MPs can contribute to respiratory innate antiviral defense.