1. Eastern Colorado Veterans Administration Geriatric Research, Education and Clinical Center (GRECC), Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
2. Division of Geriatric Medicine, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
3. Cardiovascular Pulmonary Research Laboratory, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
4. Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado Anschutz Medical Campus, Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
5. Flow Cytometry Shared Resource, University of Colorado Cancer Center, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
6. Division of Pulmonary, Critical Care and Sleep Medicine, Department of Biomedical Research, National Jewish Health, Denver, CO, USA
7. Charles C. Gates Center for Regenerative Medicine and Stem Cell Biology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA