The expression as well as the function of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel is impaired during OS, thus contributing to the progression of airway dysfunctions, including chronic obstructive pulmonary disease (COPD), consequent to alteration of the mucociliary transport in airway epithelial cells.28 This evidence concerns the gene CFTR and chronic obstructive pulmonary disease.