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Introduction: Chronic obstructive pulmonary disease (COPD) is a heterogeneous condition without effective disease modifying therapies. Identification of novel inflammatory endotype markers such as extracellular vesicles (EVs), which are important intercellular messengers carrying microRNA (miRNA), may enable earlier diagnosis and disease stratification for a targeted treatment approach. Our aim was to identify differentially expressed EV miRNA in the lungs of COPD patients compared with healthy ex-smokers and determine whether they can help define inflammatory COPD endotypes. Methods: EV miRNA were isolated and sequenced from ex-smoking COPD patients and healthy ex-smoker bronchoalveolar lavage fluid. Results were validated with RT-qPCR and compared to differential inflammatory cell counts. Results: Expression analysis identified five upregulated miRNA in COPD (miR-223-3p, miR-2110, miR-182-5p, miR-200b-5p and miR-625-3p) and three downregulated miRNA (miR-138-5p, miR-338-3p and miR-204-5p), all with a log2 fold change of >1/-1, FDR < 0.05. These miRNAs correlated with disease defining characteristics such as FEF 25-75% (a small airways disease measure) and DLCO% (a surrogate measure of emphysema). Receiver operator curve analysis demonstrated miR-2110, miR-223-3p, and miR-182-5p showed excellent combinatory predictive ability (AUC 0.91, p < 0.0001) in differentiating between health and mild COPD. Furthermore, miR-223-3p and miR-338-3p correlated with airway eosinophilia and were able to distinguish "pure eosinophilic" COPD from other airway inflammatory subtypes (AUC 0.94 and 0.85, respectively). Discussion: This is the first study to identify differentially expressed miRNA in COPD bronchoalveolar lavage fluid EVs. These findings suggest specific lung derived EV miRNA are a strong predictor of disease presence even in mild COPD. Furthermore, specific miRNA correlated with inflammatory cell numbers in COPD, and may have a role in defining inflammatory endotypes for future treatment stratification.
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Rationale: Viral infections are major drivers of exacerbations and clinical burden in patients with asthma and chronic obstructive pulmonary disease (COPD). IFN-ß is a key component of the innate immune response to viral infection. To date, studies of inhaled IFN-ß treatment have not demonstrated a significant effect on asthma exacerbations.Objectives: The dynamics of exogenous IFN-ß activity were investigated to inform on future clinical indications for this potential antiviral therapy.Methods: Monocyte-derived macrophages (MDMs), alveolar macrophages, and primary bronchial epithelial cells (PBECs) were isolated from healthy control subjects and patients with COPD and infected with influenza virus either prior to or after IFN-ß stimulation. Infection levels were measured by the percentage of nucleoprotein 1-positive cells using flow cytometry. Viral RNA shedding and IFN-stimulated gene expression were measured by quantitative PCR. Production of inflammatory cytokines was measured using MSD.Measurements and Main Results: Adding IFN-ß to MDMs, alveolar macrophages, and PBECs prior to, but not after, infection reduced the percentage of nucleoprotein 1-positive cells by 85, 56, and 66%, respectively (P < 0.05). Inhibition of infection lasted for 24 hours after removal of IFN-ß and was maintained albeit reduced up to 1 week in MDMs and 72 hours in PBECs; this was similar between healthy control subjects and patients with COPD. IFN-ß did not induce inflammatory cytokine production by MDMs or PBECs but reduced influenza-induced IL-1ß production by PBECs.Conclusions:In vitro modeling of IFN-ß dynamics highlights the potential for intermittent prophylactic doses of exogenous IFN-ß to modulate viral infection. This provides important insights to aid the future design of clinical trials of IFN-ß in asthma and COPD.