1. Lung Repair and Regeneration, Comprehensive Pneumology Center, Ludwig Maximilians University, University Hospital Großhadern, and Helmholtz Zentrum München, Member of the German Center for Lung Research, Munich, Germany
2. Lung Bioengineering and Regeneration, Lund University, Lund, Sweden
3. Department of Internal Medicine, Universities of Giessen and Marburg Lung Center, Justus Liebig University Giessen, Member of the German Center for Lung Research, Giessen, Germany; and
4. Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado, Denver, Aurora, Colorado