Anti–Peptidylarginine Deiminase 4 Autoantibodies Derived From Patients With Rheumatoid Arthritis Exert Pathogenic Effects by Activating Monocytes and Exacerbating Inflammatory Arthritis

Our findings suggest a model in which anti-PAD4 antibody binding to monocytes triggers an inflammatory cascade that promotes immune cell recruitment to the joint and T cell activation, culminating in synovial fibroblast activation and the development of more severe arthritis.