[1] Univ Roma La Sapienza, Dept Neurol & Psychiat, Fac Med, I-00185 Rome, Italy
[2] Baylor Inst Immunol Res, Multiple Sclerosis Program, Dallas, TX USA
[3] Cleveland Clin, Mellen Ctr Multiple Sclerosis Treatment & Res, Cleveland, OH 44106 USA
[4] Med Univ Lodz, Dept Neurol, Lodz, Poland
[5] Biogen Idec Inc, Cambridge, MA USA
[6] Ruhr Univ Bochum, St Josef Hosp, Dept Neurol, Bochum, Germany