Our findings of the inhibitory effects of scolopendrasin IX on the production of inflammatory cytokines in response to K/BxN serum injection suggest that autoantibody-induced inflammatory response is negatively regulated by FPR2 activation, and that a novel FPR2 agonist elicits an anti-inflammatory response in the K/BxN serum-transfer arthritis model. Here, FPR2 is linked to arthritic joint disease.