Increased production of intracellular interleukin-1 receptor antagonist type I in the synovium of mice with collagen-induced arthritis: A possible role in the resolution of arthritis

Production of IL-1Ra isoforms, particularly icIL-1Ra1, is stimulated in inflamed joints during CIA in mice. The combination of decreased production of IL-1beta and elevated levels of icIL-1Ra1 during the course of CIA was associated with a reduction in inflammatory activity. These results suggest that icIL-1Ra1 may play a role in the resolution of murine CIA.