Effect of formoterol and salmeterol on IL-6 and IL-8 release in airway epithelial cells

Summaryβ2-Adrenoceptors are widely distributed and occur on airway epithelial cells. The aim of this study was to find out whether the two long-acting β2-agonists formoterol and salmeterol influence interleukin-6 (IL-6) and -8 (IL-8) release from airway epithelial cells in vitro.A549 cells and primary bronchial epithelial cells (PBEC) were stimulated with organic dust from pig barns. Non-stimulated and dust-stimulated cells were incubated for 24h with formoterol or salmeterol (10−13–10−6M) and the release of IL-6 and IL-8 into the medium was assessed by ELISA technique. Propranolol (10−5M) or sotalol (10−3M) were used to block the β2-agonist mediated effects.Formoterol and salmeterol both induced enhancement of IL-6 and IL-8 release and added to the effect of organic dust. This enhanced release was blocked by a β-blocker in PBEC but not in A549 cells.To our knowledge, this is the first time β2-agonists have been shown to stimulate IL-6 release from airway epithelial cells. The results indicate different mechanisms of β2-agonist action in bronchial and alveolar epithelial cells. Furthermore, our results indicate that A549 cells do not possess functional β2-adrenoceptors