Mucosal defense of the lung includes the physical barrier of the epithelium and its intercellular junctions, mucociliary clearance, epithelial production of antimicrobial peptides (AMP) and oxidative agents as well as transport of IgA antibodies, as well as professional innate and adaptive immune cells, most of which are altered in COPD (8). This evidence concerns the gene CD79A and chronic obstructive pulmonary disease.