ABSTRACT
This chapter reviews the interactions of eosinophils and airway epithelial cells and examines the unique features of epithelial cell and eosinophil activation during allergic inflammation as well as the sequelae of these events on the patho-biological features of asthma. Mast cells reside within the lung epithelium and interstitial tissues and contain an important profile of preformed mediators. Tryptase, an enzyme specific to mast cells, is stored in mast cell granules and is complexed to heparin proteoglycans. The respiratory tract is continuously exposed to allergens, environmental pollutants and irritants, and viral pathogens that have the potential to directly alter airway epithelial cell function. Airway epithelial cells are activated both directly by environmental conditions and indirectly by migratory cells that then produce mediators to alter epithelial cell function. Airway eosinophils are quantitatively and phenotypically distinct from blood cells. The respiratory epithelium expresses a limited number of known adhesive ligands.
