1. Department of Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Sapporo, Japan;
2. Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Sapporo, Japan;
3. Division of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan;
4. Department of Pathology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan