Especially, the number of peripheral myeloid lineage cells was significantly decreased in GPI-immunized Padi4 KO mice, and the survival of Padi4-deficient neutrophils was impaired in vitro. Taken together, Padi4 exacerbate inflammatory arthritis with diverse immunological modifications which play certain roles in the pathogenesis of arthritis. The gene discussed is PADI4; the disease is arthritic joint disease.