1. IBD Center, Sapporo Kosei General Hospital, Sapporo, Japan.
2. Department of Gastroenterology and Hepatology, Tokyo Medical and Dental University, Tokyo, Japan.
3. Division of Gastroenterology, Department of Internal Medicine, Kyung Hee University School of Medicine, Seoul, Korea.
4. Division of Gastroenterology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
5. Department of Internal Medicine, Hanyang University Guri Hospital, Guri, Korea.
6. Inflammation & Immunology, Pfizer Japan Inc, Tokyo, Japan.
7. Center for Advanced IBD Research and Treatment, Kitasato University, Tokyo, Japan.