[1] Univ Zurich Hosp, Dept Rheumatol, Ctr Expt Rheumatol, CH-8091 Zurich, Switzerland
[2] Univ Zurich Hosp, Ctr Integrat Human Physiol, CH-8091 Zurich, Switzerland
[3] Univ Erlangen Nurnberg, Dept Internal Med 3, Erlangen, Germany
[4] Univ Erlangen Nurnberg, Inst Clin Immunol, Erlangen, Germany
[5] Univ Paris 05, Rheumatol Dept A, Paris, France
[6] Carl Gustav Carus Univ Dresden, Dept Rheumatol, Dresden, Germany
[7] Univ Pecs, Dept Immunol & Rheumatol, Pecs, Hungary
[8] Univ Genoa, Dept Internal Med, Res Lab, I-16126 Genoa, Italy
[9] Univ Genoa, Dept Internal Med, Acad Unit Clin Rheumatol, I-16126 Genoa, Italy
[10] Univ Belgrade, Inst Rheumatol, Belgrade, Serbia
[11] St James Univ Hosp, Inst Mol Med, Sect Musculoskeletal Dis, Leeds, W Yorkshire, England
[12] FESCA, Froyennes, Belgium
[13] Univ Florence, Div Rheumatol, Dept BioMed, Florence, Italy
[14] Med Univ Bialystok, Dept Rheumatol & Internal Med, Bialystok, Poland
[15] Newcastle Univ, Inst Cellular Med, Musculoskeletal Res Grp, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England
[16] Univ Giessen, Dept Rheumatol & Internal Med, Giessen, Germany
[17] Max Planck Inst Physiol & Clin Res, Kerckhoff Klin, Dept Rheumatol Clin Immunol Osteol & Phys Med, D-6350 Bad Nauheim, Germany
[18] Charite, Dept Rheumatol & Clin Immunol, D-13353 Berlin, Germany
[19] Univ Basel, Dept Rheumatol, Basel, Switzerland
[20] Univ Naples 2, Dept Rheumatol, Naples, Italy
[21] Royal Free Hosp, Dept Rheumatol, London, England