1. Section of Immunopathogenesis; Institute of Immunological Science, Hokkaido University; Sapporo Hokkaido 060-0815 Japan
2. Department of Cardiovascular Medicine; Hokkaido University Medical School; Sapporo Hokkaido 060-0815 Japan
3. Immuno-Biological Laboratories; Fujioka Gunma 375-0005 Japan
4. The London Regional Cancer Centre; London Ontario Canada