Airway submucosal glands contribute most of the mucus and antimicrobial factors in the upper airways, which are important for the normal lung host defense function. There is increasing evidence that submucosal glands function abnormally in the CF airways. Thus, it has been proposed that CF airways suffer from reduced delivery of antimicrobial factors and mucus that would abate mucociliary clearance and facilitate infection. However, the effect of inhalation of bacteria on submucosal gland mucus secretion is not fully understood. Our objective is to study the response of airway submucosal gland to bacteria inhalation and the role of CFTR. When inhaled pathogens land on the airway, they trigger the release of proinflammatory cytokines including interleukin (IL)-1β, IL-8, IL-6 and tumor necrosis factor (TNF)-α. These cytokines are elevated in CF airways. Thus, we are testing the effects of cytokines on submucosal glands mucus secretions and the role of CFTR.