Interactions between airway epithelial cells and dendritic cells: implications for the regulation of airway inflammation.

Airway epithelial cells (AEC) and dendritic cells (DC) are situated in close proximity within the airway epithelium, and are the first cells to encounter inhaled pathogens, allergens and environmental pollutants. AEC and DC interact through the release of cytokines and other soluble mediators and through direct cell-cell contact, and these interactions are likely to play an important role in maintaining immune homeostasis. Increasing evidence indicates that both AEC and DC from asthmatic individuals exhibit distinct functional properties, compared with AEC and DC from healthy individuals. Both animal models, and novel co-culture models for directly studying human AEC/DC interactions are providing new insight into the cross-talk between these two important cells types, as a foundation for the development of new drug targets for use in asthma, cystic fibrosis and chronic obstructive pulmonary disease.