1. Department of Hematology, Chiba University Hospital, Chiba, Japan;
2. Department of Hematology, International University of Health and Welfare School of Medicine, Narita, Japan;
3. Department of Transfusion Medicine and Cell Therapy, Chiba University Hospital, Chiba, Japan;
4. Department of Blood Transfusion, Toho University Medical Center Sakura Hospital, Chiba, Japan; and
5. Department of Neurology, Chiba University Graduate School of Medicine, Chiba, Japan