1. Bone Marrow Transplantation Center, University Hospital Eppendorf, Hamburg, Germany.
2. Bone Marrow Transplantation Center, University Hospital Eppendorf, Hamburg, Germany; St. Petersburg State Pavlov Medical University, St. Petersburg, Russia.
3. EUFETS, Idar-Oberstein, Germany
4. Department of Pediatric Hematology/Oncology, University Hospital Eppendorf, Hamburg, Germany
5. University Hospital Mannheim, Germany