Endogenous IL-22 Plays a Dual Role in Arthritis: Regulation of Established Arthritis via IFN-γ Responses

Abstract

We show for the first time that IL-22 plays a dual role: protective prior to the onset of arthritis and pathogenic after onset of arthritis. The pathogenic effect of IL-22 is dependent on suppression of IFN-γ responses. IL-17 responses remained unchanged with the administration of anti-IL22 antibody. IL-22R1 is upregulated on CD4+T cells during arthritis and regulates IFN-γ in T cells.