Control of Stem Cell Differentiation in the Lung

It is well recognized that mesenchymal stem cells are immunomodulatory. They secrete a variety of antiinflammatory growth factors and cytokines and have the capacity to stimulate reparative processes. This makes them attractive for use in clinical situations where it would be of interest to stimulate repair of diseased or injured tissues. Much effort has gone into identifying stem cells and characterizing their functioning in tracheobronchial, bronchiolar and alveolar compartments of the lung. This has been aided by the development of experimental systems where exposure to chemical toxicants including ozone and mineral fibers can stimulate stem cell proliferation and polarization. The use of these isolated stem cell populations has shown promise in mitigating chemical-induced lung injury by stimulating normal lung cell proliferation and differentiation.