1. Department of Medicine, Rheumatology Unit, Karolinska Hospital, 17176 Stockholm, Sweden
2. Department of Rheumatology, Astrid Lindgren's Children's Hospital, Karolinska Institutet, 17176 Stockholm, Sweden
3. Laboratory of Biomedical Science, North Shore University Hospital, New York University School of Medicine, Manhasset, New York 11030
4. Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, New York 10021