The air–liquid interface model

Abstract

The airway epithelium lining the airways is in first contact with the inhaled environment, which contains allergens, gaseous pollutants, particulates, and pathogenic microorganisms. It forms an ion- and size-selective barrier between the inhaled environment and the underlying tissue by the formation of intercellular tight junctions and adhesion junctions. Additionally, the airway epithelium plays an important role in innate immune defense, expressing receptors that recognize molecular patterns from pathogenic microbes, parasites, fungi, and allergens and danger signals from damaged cells, directing proinflammatory processes. Chronic lung diseases, such as asthma and chronic obstructive pulmonary disease, involve changes in airway epithelial function. For valuable insights into these changes, in vitro models should closely recapitulate human airway epithelial composition, three-dimensional structure, and function as an immunological barrier. The goal of this chapter is to review the literature on the use of air–liquid interface cultures to model the lung epithelium in health and disease.</p