Sanquin Research, Department of Experimental Immunohematology, Amsterdam, The Netherlands. Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands. Department of Pediatric Hematology, University Medical Center Utrecht, Utrecht, The Netherlands. Laboratory for Platelet and Leukocyte Serology, Department of Immunohematology Diagnostics, Sanquin Diagnostic Services, Amsterdam, The Netherlands. Sanquin Research, Center for Clinical Transfusion Research, Leiden, The Netherlands. Jon J van Rood Center for Clinical Transfusion Science, Leiden University Medical Center, Leiden, The Netherlands. Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, The Netherlands.