Factors controlling transduction signaling and proliferation of airway smooth muscle.

The airway smooth muscle cell is an active participant in the inflammatory response that accompanies asthma. It can interact with the epithelium and inflammatory cells to produce cytokines and cell surface molecule upregulation. Moreover, smooth muscle cells can alter the composition of the extracellular matrix proteins via changes in the production of matrix metalloproteinases and their tissue inhibitors. These properties may contribute to the increase in the amount of airway smooth muscle that characterizes the asthmatic airway wall and the remodeling that underlies the structural changes that lead to persistent asthma.