1. Department of Neurology, University of Alabama and the Birmingham VA Medical Center, Birmingham, Alabama 35294, USA
2. Neuroimmunology Branch, NINDS/NIH, Bethesda, Maryland 20892, USA
3. Institute of Neurology National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
4. Research and Medical Programs Department, National Multiple Sclerosis Society, New York, New York 10017, USA