Rheumatoid Factor as a Potentiator of Anti–Citrullinated Protein Antibody–Mediated Inflammation in Rheumatoid Arthritis

Abstract

The combined presence of ACPAs and IgM-RF mediates increased proinflammatory cytokine production in vitro and is associated with increased systemic inflammation and disease activity in RA. Our data suggest that IgM-RF enhances the capacity of ACPA ICs to stimulate macrophage cytokine production, thereby providing a mechanistic link by which RF enhances the pathogenicity of ACPA ICs in RA.