1. Department of Bioengineering, University of Pittsburgh, 236 Bridgeside Point II, 450 Technology Drive, PA 15219, USA
2. Department of Orthopedic Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15219, USA
3. Stem Cell Research Center, University of Pittsburgh, Pittsburgh, PA 15219, USA
4. David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095, USA
5. Orthopaedic Hospital Research Center, University of California at Los Angeles, Los Angeles, CA 90095, USA
6. Center for Cardiovascular Science, Queen’s Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK
7. McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15219, USA