Evidence that Calu-3 human airway cells secrete bicarbonate

Michael C. Lee, Christopher M. Penland, Jonathan H. Widdicombe, Jeffrey J. Wine
1998 American Journal of Physiology - Lung cellular and Molecular Physiology  
Calu-3 cell line is being investigated as a model for human submucosal gland serous cells. In a previous investigation of basal short-circuit current (I sc ) in Calu-3 cells, high levels of bumetanide-insensitive basal I sc (ϳ60 µA/cm 2 ) were measured in cells grown at an air interface. Basal I sc was reduced only 7% by bumetanide, and the largest component of basal I sc required both Cl Ϫ and HCO 3 Ϫ in the bathing solutions. Because I sc could be partially inhibited by basolateral
more » ... stilbene-2,2Ј-disulfonic acid and because the only known apical exit pathway for anions is the cystic fibrosis transmembrane conductance regulator, which has a relatively poor conductance for HCO 3 Ϫ , it was concluded that most basal I sc is HCO 3 Ϫ -dependent Cl Ϫ secretion [M. Singh, M.
doi:10.1152/ajplung.1998.274.3.l450 fatcat:egfzdsfhvvd45iegxbckyrt6fy