1. Cell and Gene Therapy, Department of Biomedicine, University of Basel, and Department of Surgery, Basel University Hospital, Hebelstrasse 20, CH-4031 Basel, Switzerland
2. Institute for Experimental Surgery, Rostock University Medical Center, Schillingallee, D-18057 Rostock, Germany
3. Institute of Anatomy, University of Bern, Baltzerstrasse 2, CH-3000 Bern, Switzerland