Impaired antiviral immunity in frequent exacerbators of chronic obstructive pulmonary disease.

Respiratory viruses cause chronic obstructive pulmonary disease (COPD) exacerbations. Rhinoviruses (RVs) are the most frequently detected. Some patients with COPD experience frequent exacerbations (≥2 exacerbations/yr). The relationship between exacerbation frequency and antiviral immunity remains poorly understood. The objective of this study was to investigate the relationship between exacerbation frequency and antiviral immunity in COPD. Alveolar macrophages and bronchial epithelial cells (BECs) were obtained from patients with COPD and healthy participants. Alveolar macrophages were infected with RV-A16 multiplicity of infection (MOI) 5 and BECs infected with RV-A16 MOI 1 for 24. Interferons (IFNs) and proinflammatory cytokines IL-1β, IL-6, C-X-C motif chemokine ligand (CXCL)-8, and TNF were measured in cell supernatants using a mesoscale discovery platform. Viral load and interferon-stimulated genes were measured in cell lysates using quantitative PCR. Spontaneous and RV-induced IFN-β, IFN-γ, and CXCL-11 release were significantly reduced in alveolar macrophages from patients with COPD compared with healthy subjects. IFN-β was further impaired in uninfected alveolar macrophages from patients with COPD with frequent exacerbations 82.0 pg/mL versus infrequent exacerbators 234.7 pg/mL, = 0.008 and RV-infected alveolar macrophages from frequent exacerbators 158.1 pg/mL versus infrequent exacerbators 279.5 pg/mL, = 0.022. Release of proinflammatory cytokines CXCL-8, IL-6, TNF, and IL-1β was higher in uninfected BECs from patients with COPD compared with healthy subjects but there was no difference in proinflammatory response to RV between groups. IFN responses to RV were impaired in alveolar macrophages from patients with COPD and further reduced in patients with frequent exacerbations. COPD exacerbations are commonly triggered by viral infections. Some patients with COPD have frequent exacerbations leading to rapid lung function decline and increased mortality. In this study, antiviral responses (interferons) from bronchial epithelial cells and alveolar macrophages were reduced in patients with COPD compared with healthy participants and further reduced in patients with COPD with frequent exacerbations. Impaired antiviral immunity may lead to frequent COPD exacerbations. Targeted vaccinations and antiviral therapy may reduce exacerbations in COPD.