BCR and systemic lupus erythematosus: In order to screen the potential autoantibody clones from BCR repertoire of two SLE patients, we downloaded all the known autoantibody IGH sequences from IMGT/LIGM-DB database, and investigated the sequence number from BCR repertoire of two SLE patients that had the same IGHV, IGHJ and H-CDR3 AA length with the known autoantibody (Table 3; Zhang et al. 2013).