1. Department of Experimental, Diagnostic and Specialty Medicine, Institute of Hematology “L. e A. Seràgnoli,” University of Bologna, Bologna, Italy
2. Immunoregulation Laboratory, Division of Transplantation Immunology & Mucosal Biology, MRC Centre for Transplantation, King's College London, Guy's Hospital, UK
3. Ludwig Center for Cancer Research, University of Lausanne, Lausanne, Switzerland