IL6 and chronic obstructive pulmonary disease: Lung epithelial cells with higher IRP2 expressions are accompanied by increased secretion of airway mucus, elevated airway remodeling, dysregulated infiltrated immune cells expressing inflammatory mediators (IL-33, IL-6), which contribute to the severity of acute COPD exacerbations secretion, and declined FEV1 in CS-induced COPD mice [86, 89, 90].