1. Department of Medicine and
2. Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital; Harvard Medical School, Boston, MA 02115, USA.
3. Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
4. Section on Immunology and Immunogenetics, Joslin Diabetes Center, Harvard Medical School, One Joslin Place, Boston, MA 02215, USA.