Further studies on adult stem cells are needed to answer many important questions about their development and ability to home in to sites of injury. Mechanisms of Lung Regeneration One approach is the interactions between epithelial and mesenchymal cells in the reparative niche because crosstalk between these populations is known to be an essential process for proper development of the lung. Derivation of lung mesenchymal lineages from the fetal mesothelium requires hedgehog signaling for mesothelial cell entry. Such iPSCs are also useful for generating patient-specific disease models and for testing new drugs and therapies Yu et al. Stem cells are among the most fascinating cells in the human body. These transplanted cells then engrafted in the recipient lung, differentiating into lung epithelium while maintaining long-term transgene expression.
Stem Cells. An alternative mechanism suggests that murine hMSCs home to lung in response to injury, ultimately adopting an epithelium-like phenotype, reducing inflammation and collagen deposition in lung tissue of mice challenged with bleomycin Ortiz et al. Similarly designed studies are projected to apply MSC therapy to patients with arrested lung and vascular growth in chronic lung diseases associated with prematurity. Proc Am Thorac Soc. Asthma is one of the most common chronic inflammatory diseases associated with airway reactivity and inflammation that result in lung injury Boyton et al. The injected stem cells may directly induce an immune response or may have a modifying effect on the immune system.
Since hMSCs are sensitive to their site-specific microenvironment, it is anticipated that they will deliver the bioactive agents in a site-specific manner quite different from pharmaceutical drugs currently on the market. J Biomed Sci. N Engl J Med , However, some recent studies suggest that this behaviour is induced by the culture conditions in progenitor cells , the progeny of stem cell division that normally undergo a strictly limited number of replication cycles in vivo.
Annual Review of Physiology. Globe and Mail. Cell therapy represents a very promising approach in many clinical fields, and numerous clinical trials with stem cells are currently in progress. Proc Am Thorac Soc. Leukemia , Stem cells have many clinical implications in the lung.