1. Institute of Pathology, University Hospital Heidelberg, Germany
2. Institute of Pathology, Charité University Hospital, Berlin, Germany
3. Institute of Pathology, University Hospital Halle and Institute of Pathology, University Hospital Leipzig, Germany
4. Department of Dermatology, Venereology and Allergology, University Medical Center and Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
5. German Red Cross Blood Service and Institute for Transfusion Medicine and Immunohematology, Goethe University Medical School, Frankfurt, Germany
6. Department of Dermatology, University Hospital Heidelberg, Germany
7. Institute of Pathology, University of Ulm, Ulm, Germany
8. Present address: Harvard Medical School, Massachusetts General Hospital, Department of Pathology, Boston, MA, USA
9. Department of Pathology, Hematopathology Section and Lymph Node Registry, Christian-Albrechts-University of Kiel, Germany
10. National Center for Tumor Diseases, Heidelberg, Germany