Fig. 5.
Potential mechanisms of mesenchymal stromal cells (MSCs) in the lung repair process in acute respiratory distress syndrome. MSCs exert a number of properties to enhance repair and restoration of physiologic function after ventilator-induced lung injury. The effects seem to be paracrine mediated and dependent in part on keratinocyte growth factor produced by the stromal cells. The bone marrow–derived MSC could transfer their mitochondria into lung epithelial cells resulting in increased alveolar adenosine triphosphate concentrations and enhanced cellular bioenergetics and improved lung function. The MSC may also be able to differentiate into alveolar type I (ATI) and type II (ATII) epithelial cells.