1. Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA
2. Department of Orthopedic Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA
3. Stem Cell Research Center, University of Pittsburgh, Pittsburgh, PA 15219, USA
4. Research Laboratory of Electronics and Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
5. Center for Cardiovascular Science, Queen’s Medical Research Institute, Edinburgh EH16 4TJ, UK
6. MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH16 4UU, UK
7. UCLA Orthopaedic Hospital, Department of Orthopaedic Surgery and David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095, USA
8. McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15219, USA
9. Medical School and Regenerative and Translational Medicine Institute, University of Texas Health Science Center at Houston, Houston, TX 77030, USA