Interleukin-33 as a marker for disease activity in rheumatoid arthritis

Background Rheumatoid arthritis (RA) is a chronic systemic inflammatory disorder thought to be autoimmune in nature and predominately affects synovial joints. Interleukin-33 (IL-33) is a newly reported cytokine of the IL-1 family. Aim of the work The aim of this study was to assess the role of IL-33 in the pathogenesis of RA. Patients and methods Group A included 30 adult patients with RA; all cases were diagnosed according to the American College of Rheumatology criteria for RA. Group B included 20 healthy adult persons (age and sex matched) who comprised the control group. The serum IL-33 levels were examined by using the enzyme-linked immunosorbent assay for 30 patients with RA and 20 healthy individuals. Disease activity was assessed according to disease activity score 28–C-reactive protein (CRP) scale. Results IL-33 was increased in all RA patients compared with controls. IL-33 was highly correlated to erythrocyte sedimentation rate, CRP, rheumatoid factor, anti-cyclic citrullinated peptide, and disease activity score 28–CRP score. Therefore, IL-33 most probably has a significant role to play in the pathogenesis of RA. Conclusion IL-33 most probably has a significant role in the pathogenesis of RA. IL-33 serum levels paralleled the severity of the disease subset. Understanding the functions of IL-33 is important for the development of new therapeutic approaches including IL-33 inhibitors as a therapeutic target.