[1] Hasselt Univ, Biomed Res Inst, Diepenbeek, Belgium
[2] Maastricht Univ, Sch Mental Hlth & Neurosci, Maastricht, Netherlands
[3] Univ Nijmegen, Multiple Sclerosis Ctr Nijmegen, Nijmegen, Netherlands
[4] Univ Nijmegen, Med Ctr, Lab Pediat & Neurol, Nijmegen, Netherlands
[5] Natl MS Ctr, Melsbroek, Belgium
[6] Hasselt Univ, Multiple Sclerosis & Rehabil Ctr, Overpelt, Belgium
[7] Vrije Univ Amsterdam, Med Ctr, Dept Mol Cell Biol & Immunol, Amsterdam, Netherlands