1. Department of Visceral Surgery, University Medical Center Freiburg, Freiburg, Germany
2. Faculty of Biology, University of Freiburg, Freiburg, Germany
3. Institute of Molecular Medicine and Cell Research, University Medical Center Freiburg, Germany and Center for Biological Signalling Studies BIOSS, Albert-Ludwigs-University Freiburg, Freiburg, Germany
4. Department of Experimental Medicine I, Nikolaus-Fiebiger-Center for Molecular Medicine, University Erlangen-Nürnberg, Erlangen, Germany