1. Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania.
2. Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania.
3. McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.
4. Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania.
5. Department of Cardiothoracic Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.