Disclosed are polypeptides comprising an amino acid sequence at least 90% identical to the amino acid sequence set forth in SEQ ID NOs 62, 64, 78, 80, 92, 96, 66, 68, 70, 82, 84, 86, 94 or 98 (sequences as defined in the complete specification). Also disclosed is the use of such polypeptides to treat autoimmune diseases such as systemic lupus erythematosus (SLE).