A previous study showed that Padi4-deficiency and the pan-PAD inhibitor Cl-amidine (55) did not ameliorate nephritis in MRL/lpr mice and another lupus model induced by the transfer of SLE sera to FcγRIIAγ−/−Mac1−/− mice, respectively (56). This evidence concerns the gene PADI4 and systemic lupus erythematosus.