1. Institute of Immunology, Faculty of Medicine, University of Oslo, Oslo, Norway, , Department of Neurology, Oslo University Hospital - Ullevål, Oslo, Norway
2. Department of Neurology, Oslo University Hospital - Ullevål, Oslo, Norway
3. Vitas AS, Oslo, Norway
4. Department of Medicine, Boston University Medical Center, Boston, MA, USA
5. Neurological Clinic, University of Ferrara, Ferrara, Italy