1. Istituto Clinico Humanitas IRCCS, 20089 Rozzano, Milan and
2. Istituto di Patologia Generale, Università degli Studi di Milano, Via Luigi Mangiagalli 31, 20133 Milan, Italy;
3. Division of Rheumatology, Allergy, and Immunology, Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114;