9705600 Waters Cells lining the airways of the lung protect the lung from inhaled toxins and harsh environmental conditions. Maintenance of this protective barrier depends upon the contacts between the cells and the re-growth of cells following injury. The cell barrier can be injured by oxidative species due to ozone, cigarette smoke, or infectious agents. The response of the cells to such injury and the repair of disruptions in the barrier are not well understood. Furthermore, although air flow in the lungs causes variations in the expansion of the airways, little is known about the effect of such mechanical strain on airway function. This proposal will investigate the maintenance and repair of the airway cell barrier following oxidant injury. A major goal of the proposed work is to develop techniques for the evaluation of barrier function while cells are mechanically stretched. There is currently no method for measuring the barrier properties of stretched cells. A novel device will be used to apply stretch to lung cells grown on elastic membranes. The barrier properties of the cells will be determined by measuring the electrical resistance across the cells. Using this tissue model, the response of the cells to oxidative damage will be measured, and the repair of the tissue will be evaluated. In addition, factors which may be important in protecting the cells or in enhancing repair will be investigated. This will lead to a better understanding of the injury and repair of the lung. ***
