1. Department I of Internal Medicine, University Hospital of Cologne, Cologne, Germany
2. Department of Hematology & Oncology, Okayama University Hospital, Okayama, Japan
3. Laboratory for Tumor & Transplantation Immunology & Stem Cell Transplantation Program, Department I of Internal Medicine, University Hospital Cologne, Kerpener Str. 62, 50924 Cologne, Germany.