Ion transport by tracheal epithelial cells in culture

In culture, cells from the dog tracheal epithelium form confluent cell sheets that have ion transport processes similar to those of the original tissue. Cell sheets grown from "normal" human tracheal mucosa resemble those of the dog in the presence of active chloride secretion, which can be stimulated by endogenous mediators. Tracheal cells cultured from patients with cystic fibrosis lack chloride secretion because their apical membranes are impermeable to this anion.