Article Type

Original Study


Objectives The objective of this study was to detect the level of interleukin-33 (IL-33) in patients with rheumatoid arthritis (RA) and to explore the relationship between the level of IL-33 in the serum with the disease activity and functional performance. Background Cytokines are important mediators of immune functions in humans and animals. IL-33, a newly found IL-1 family cytokine, is involved in joint inflammation in RA. Therefore, we aimed to investigate the immunopathological roles of IL-33 in serum RA patients. Patients and methods This study was conducted on a total of 80 individuals: 60 of them were RA patients (55 female and five male) and 20 healthy controls (17 female and three male). All RA patients and controls were evaluated by measuring complete blood count, erythrocyte sedimentation rate, C-reactive protein (CRP), anticitrullinated proteins (anti-CCP), and rheumatoid factor (RF). IL-33 level was measured in the serum of both RA patient group and control group. Results The mean erythrocyte sedimentation rate, serum CRP, anti-CCP antibodies, and RF in addition to the detection percentages of serum IL-33 were significantly higher in the RA group than in the control group. In the RA group, serum IL-33 showed significantly positive correlations with DAS-28, visual analogue scale, RF, CRP, and anti-CCP antibodies. Conclusion IL-33 has an important proinflammatory role in the pathogenesis of RA. Considering their correlation with disease activity, they may become potential therapeutic targets for RA.