Medical University Lausitz, Karolinska Institutet - Department of Medicine, Leiden University, Leiden University, University of Warsaw - Medical University of Warsaw, Medical University of Warsaw - Department of Haematology, Transplantation and Internal Medicine, - Department of Internal Medicine II, Leiden University, Centre National de Greffe de Moelle Osseuse, Pavlov University, Hospital Universitari i Politècnic La Fe, Universitat Autònoma de Barcelona, IRCCS Istituto Giannina Gaslini, Children's Hospital in Krakow, Hospital de la Santa Creu i Sant Pau, IRCCS Ospedale Policlinico San Martino, Assistance Publique-Hôpitaux de Paris - Hôpital Saint-Louis, Hacettepe University, University of Padova, Nicolaus Copernicus University, Children's Hospital Westmead, Instituto de Investigación Sanitaria Hospital "12 de Octubre" - Department of Hematology, Hadassah Hebrew University, University Medical Center Hamburg- Eppendorf - University Children's Hospital, Jena University - Jena University Hospital, Central Hospital of Southern Pest, Niño Jesus Children`s Hospital, IRCCS Ospedale Policlinico San Martino, Medical University Lausitz, Medical University Lausitz, Nicolaus Copernicus University and Hospital de la Princesa - Hematology Department