1. Department of Biomaterials, University of Ulm, Ulm, Germany
2. Institute for Biological Interfaces, Karlsruhe Institute of Technology (KIT) Karlsruhe, Germany
3. Institute for Heart and Circulation Research, Hamburg, Germany
4. Institute for Transplantation Diagnostics and Cell Therapeutics, Medical Center of University Düsseldorf, Germany
5. Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Berlin and Teltow, Germany