Use of primary cell culture to study regulation of airway surface epithelial mucus secretion

Airway mucus glycoproteins are produced by two different tissues, ie, surface epithelium and submucosa glands. Due to the coexistence of these sources in the same organ, it has been difficult to study the regulation of mucin synthesis and secretion from each source. We have recently developed and characterized a primary culture from tracheal surface epithelium which is highly enriched in secretory cells and produces authentic mucins. Mucins produced by the cultures are extremely hydrophobic. A pool of mucins is localized on the cell surface of secretory cells and these cell surface mucins are released by neutrophil elastase. The simplicity and the relatively rich secretory cell population of the present culture system will serve as a useful model in studying the cell biology of mucin as well as pharmacology of airway surface epithelial mucus secretion.