1. National Medical Center, Institute of Hematology and Immunology, 1113 Budapest, Hungary
2. Institute of Enzymology, Hungarian Academy of Sciences, 1113 Budapest, Hungary
3. Research Group for Membrane Biology, Hungarian Academy of Sciences, 1113 Budapest, Hungary
4. Georg Speyer Haus, Institute for Biomedical Research, D-60696 Frankfurt, Germany
5. Free University of Amsterdam, 1081 HV Amsterdam, The Netherlands
6. Central Laboratory, Netherlands Red Cross Blood Transfusion Service, 1066 CX Amsterdam, The Netherlands
7. Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
8. National Medical Center, Institute of Hematology and Immunology, 1113 Budapest, Hungary; Research Group for Membrane Biology, Hungarian Academy of Sciences, 1113 Budapest, Hungary