1. Department of Neurology and Geriatrics Kagoshima University Graduate School of Medical and Dental Sciences Kagoshima Japan
2. Division of Neuroimmunology, Joint Research Center for Human Retrovirus Infection Kagoshima University Kagoshima Japan
3. Division of Neurology, Department of Internal Medicine St. Marianna University School of Medicine Kawasaki Japan
4. Clinical Research Promotion Center The University of Tokyo Hospital Bunkyo‐ku Japan