PADI4 and systemic lupus erythematosus: Further ELISA assays indicated that among the 16 autoAbs tested, the levels of 12 autoAbs targeting APEX1, HMGB1, PADI4, IFIT5, POLB, VRK1, UBE2S, SRP19, AURKA, MAPKAPK3, AGO1 (EIF2C1), and RGS3 remained significantly increased in SLE compared with NC (P < 0.05, Figure 2A–L).