Environmental responses of virally infected respiratory epithelial cells

Abstract

Background: Rhinovirus, airborne pollution, and allergens are thought to contribute to epithelial dysfunction in chronic airway disease. Objectives were to determine whether these factors act in synergism to induce inflammation and chronic airway disease. Methods: Respiratory mucosa from chronic rhinosinusitis with nasal polyps (CRSwNP) (n=7) or healthy (n=6) patients were cultured at air-liquid interface (ALI) (culture wells n=204). Cells were infected with rhinovirus, then exposed to combinations of vehicle, diesel particulate matter (DPM), and house dust mite (HDM). Ciliary beating frequency (CBF), interleukin (IL)-6 release, and cytotoxicity were assessed by Sisson-Ammons Video Analysis (SAVA) software, flow cytometry, and LDH assays. Results: Compared with healthy cultures, CRSwNP culture groups had lower baseline CBF. The CBF of virally infected ALI cultures was higher than healthy cultures. Challenges tended to impair CBF more in cells that were also virally infected. There was an elevation in IL-6 with viral infection. Challenge combinations did not cause a different IL-6 or CBF response within groups. Conclusions: An inherent mucosal dysfunction and environmental exposures can worsen sinus disease. Synergism in CBF impairment or IL-6 release was not seen.