Suppression of pulmonary innate host defense in smokers

Background: Smoking increases the susceptibility to pulmonary infection and is a risk factor for the development of chronic obstructive pulmonary disease (COPD). We postulated that cigarette smoke suppresses the activation of the innate immune system in response to bacterial infection. Methods: With sensitive ex-vivo analysis we measured the level of the endogenous antibiotic peptide human beta-defensin-2 in pharyngeal washing fluids and sputum of patients with community acquired pneumonia. The regulation of antibacterial host defense molecules was studied in vitro. The effect of cigarette smoke on the antibacte…