1. Pediatric Oncology research laboratory, The University Hospital Rigshospitalet, Copenhagen, Denmark
2. The Tissue Typing Laboratory, Department of Clinical Immunology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark
3. Department of Pediatrics and adolescent medicine, The University Hospital Rigshospitalet, Copenhagen, Denmark
4. Department of Pediatrics, University of Iceland, Reykjavík, Iceland
5. Division of Pediatric Hematology, Oncology and Stem Cell Transplantation, Children and Adolescents, Helsinki University Hospital, Helsinki, Finland
6. Children's Hospital, Vilnius University Hospital Santaros Klinikos and Vilnius University, Vilnius, Lithuania
7. Department of Pediatrics, St. Olavs Hospital, Trondheim; Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
8. Department of Pediatrics, Institution for Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
9. Tallinn Children's Hospital, Tallinn, Estonia
10. Institute of Clinical Medicine, Faculty of Medicine, University of Copenhagen, Denmark