Assessment of serum interleukin-20 and interleukin-33 levels in rheumatoid arthritis patients

Abstract

Background

Understanding the role of cytokines in progression and pathogenesis of rheumatoid arthritis (RA) may help in development of new treatment strategies.

Aim of the work

To detect the interleukin–20 (IL-20) and interleukin-33 (IL-33) serum levels in RA patients and to assess their relationship with disease activity.

Patients and methods

This study was done on 30 RA patients and 30 matched controls. Disease activity score (DAS 28) was assessed. Level of IL-20 and IL-33 were measured by using Enzyme linked immunosorbent assay.

Results

The level of IL-20 and IL-33 were significantly elevated in the RA patients (37 ± 17.8 ng/L and 102.6 ± 17.5 ng/L) compared to controls (13.6 ± 1.9 ng/L and 44.6 ± 10.5 ng/L; p < 0.001 for both) and level of each cytokine was significantly changed according to DAS 28 disease activity score. ROC curve analysis demonstrated that both IL-20 and IL-23 had excellent diagnostic accuracy in differentiation of RA patients from healthy controls with 80 % and 93.3 % sensitivity and 80 % and 83.3 % specificity respectively. Also, IL33 level was considered an accurate discriminating marker between RA patients and controls. Regression analysis highlights that DAS-28 is predictor for both IL-20 and IL-33.

Conclusion

A significant higher levels of serum IL-20 and IL-33 was observed in RA patients, and both were associated with the disease activity. Also, IL-33 was effective in differentiation between RA cases and controls. These findings indicate that IL-20 and IL-33 could be useful biomarkers for assessing disease activity in RA and both may serve as potential targets for future treatment of the disease.