Novel insights into the effects of cigarette smoke on the airway epithelial surface—lessons learned at the European Respiratory Society International Congress 2018 in Paris

The airway epithelium displays a multitude of host defense mechanisms against micro-organisms including mucociliary clearance, antibacterial activity of secreted proteins, and maintenance of the epithelial barrier integrity. Cigarette smoke (CS) exposure of airway epithelial cells is proposed to impair these host defense properties, thereby increasing the susceptibility towards microbial infections, and furthermore initiating epithelial remodeling and airway inflammation. During the 2018 ERS congress novel data were presented, that corroborate the detrimental outcomes of exposure to CS or the presence of chronic obstructive pulmonary disease (COPD) on the diverse host defense functions of the airway epithelium.