Mesenchymal stem cell therapy for the treatment of chronic obstructive pulmonary disease.

Recent studies have revealed that adult stem cells such as bone marrow-derived cells contribute to lung tissue regeneration and protection, and thus administration of exogenous stem/progenitor cells may be a potent next-generation therapy for COPD. Pathogenesis of COPD is characterized by an upregulation of inflammatory processes leading to irreversible events such as apoptosis of epithelial cells, proteolysis of the terminal air-space and lung extracellular matrix components. The available pharmacological treatments are essentially symptomatic, therefore, there is a need to develop more effective therapeutic strategies. It has been previously demonstrated that transplanted MSC home to the lung in response to lung injury and adopt phenotypes of alveolar epithelial cells, endothelial cells, fibroblasts and bronchial epithelial cells. However, engraftment and differentiation are now felt to be rare occurrences and other mechanisms might be involved and play a more important role. Importantly, MSCs protect lung tissue through suppression of proinflammatory cytokines, and through triggering production of reparative growth factors. Accordingly, it is not clear if and how these cells will be able to repair, to slow or to prevent the disease. This article reviews recent advances in regenerative medicine in COPD and highlights that their potential application although promising and very attractive, are still a far away opinion.