The airways are lined with a film of fluid ~10µ deep that acts as the first line of defense against inhaled pathogens, dirt, and noxious vapors. Transepithelial fluid movements driven by active transepithelial ion transport serve to regulate the depth of this airway surface liquid. In the larger airways, a mucus gel derived from both glands and surface epithelium entraps inhaled particles, which are then removed by the coordinated beating of cilia. Both glands and epithelium secrete a wide variety of antimicrobial and other protective substances in addition to mucins. Substances released across the basolateral surface of the epithelium attract leukocytes and influence neighboring tissues. Here, after reviewing the basic structure of mammalian airway epithelium, I discuss its various defensive functions and how they are altered in airway disease.
Table of Contents
Overview
Surface Epithelium
Airway Glands
Pathology
References
Author Biography
About the Author(s)
Jonathan Widdicombe, Department of Physiology and Membrane Biology, University of California at Davis, School of Medicine
Jonathan Widdicombe received a B.A. in Zoology and a D. Phil. in Pharmacology from Oxford. From 1976 to 2003 he worked at the Cardiovascular Research Institute and the Department of Physiology at the University of California – San Francisco. Since 2000, he has been a Professor of Physiology and Membrane Biology at the University of California – Davis. From 1988 to 2003, he was Director of a “Specialized Center of Research” into cystic fibrosis, funded by the National Institutes of Health.
