Mesenchymal stem cells and acute lung injury

Abstract

Acute respiratory distress syndrome (ARDS) is a clinical syndrome of acute respiratory failure presenting with hypoxemia and bilateral pulmonary infiltrates, most often in the setting of pneumonia, sepsis, or major trauma. The pathogenesis of ARDS involves lung endothelial injury, alveolar epithelial injury, and the accumulation of protein-rich fluid and cellular debris in the alveolar space. No pharmacologic therapy has so far proved effective. A potential strategy involves cell-based therapies, including mesenchymal stem cells (MSCs). Herein we review basic properties of MSCs, their use in preclinical models of lung injury and ARDS, and potential therapeutic mechanisms.

Figure 1

Beneficial effects of mesenchymal stem cells (MSCs) in acute lung injury. This figure depicts protein-rich edema fluid and inflammatory cells filling an injured alveolus after endothelial and epithelial injury. MSCs exert immunomodulatory effects on neutrophils, lymphocytes, and macrophages, assist in repair of the injured epithelial and endothelial barriers, improve alveolar fluid clearance, and secrete several molecules including the antibacterial peptide LL-37, angiopoietin-1 (ANG-1), and keratinocyte growth factor (KGF).