[1] Univ Amsterdam, Acad Med Ctr, Dept Clin Immunol & Rheumatol, Amsterdam Rheumatol & Immunol Ctr, NL-1100 DE Amsterdam, Netherlands
[2] Univ Amsterdam, Acad Med Ctr, Dept Neurosurg, NL-1100 DE Amsterdam, Netherlands
[3] GlaxoSmithKline, Stevenage, Herts, England
[4] Univ Cambridge, Cambridge, England