1. Division of Transplantation, Department of Surgery, Medical University of Vienna, Austria
2. Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School (MHH), Hannover, Germany
3. Institute of Clinical Pathology, Medical University of Vienna, Austria
4. Transplantation Centre and Transplantation Immunopathology Laboratory, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne University, Lausanne, Switzerland