1. Kanto‐Koshinetsu Block Blood Center Japanese Red Cross Society Tokyo Japan
2. Department of Clinical Laboratory Science Sanyo Women's College Hiroshima Japan
3. Institute for Clinical Immunology and Transfusion Medicine Justus Liebig University Giessen Giessen Germany
4. Research and Development Department Japanese Red Cross Central Blood Institute Tokyo Japan
5. Division of Transfusion Medicine Hiroshima University Hiroshima Japan
6. Japanese Red Cross Society Chushikoku Block Blood Center Hiroshima Japan