Egyptian Rheumatology and Rehabilitation (Jan 2017)
Correlation between disease activity and serum interleukin-23 in rheumatoid arthritis
Abstract
Background Interleukin-23 (IL-23) is a proinflammatory cytokine that is thought to be central to the development of autoimmune diseases. This study was conducted to determine whether or not serum concentration of IL-23 is elevated in patients with rheumatoid arthritis (RA) and to determine the relationship between the IL-23 level and disease activity in patients with RA. Patients and methods Serum samples were obtained from 100 patients with RA and 50 healthy controls. Clinical parameters of the disease were determined, including 28-Joint Disease Activity Score, Clinical Disease Activity Index, Health Assessment Questionnaires, C-reactive protein, rheumatoid factor levels, anti-cyclic citrullinated peptide antibodies, and degree of bony erosions based on radiographs. The levels of IL-23 were determined by enzyme-linked immunosorbent assay (ELISA). The correlations between the serum levels of IL-23 and disease activity parameters of patients with RA were determined. Results Serum IL-23 level was significantly elevated in patients with RA, 0.00–49.30 pg/ml (19.12±13.45 pg/ml) compared with healthy controls, 0.00–1.40 pg/ml (0.90±0.63 pg/ml) (P=0.0001). Serum IL-23 levels in patients with RA correlated with Clinical Disease Activity Index (r=0.952, P=0.000), Health Assessment Questionnaires (r=0.953, P=0.000), and 28-Joint Disease Activity Score (r=0.967, P=0.000). Moreover, serum IL-23 levels in patients with RA correlated with erythrocyte sedimentation rate (r=0.950, P=0.000), C-reactive protein (r=0.954, P=0.001), and rheumatoid factor (r=0.917, P=0.000). There was a statistically significant difference between IL-23 mean values associated with different radiograph classes in patients with RA (P=0.001). Conclusion Levels of serum IL-23 in patients with RA were significantly higher than in healthy controls. Moreover, elevated serum IL-23 levels were correlated with clinical and laboratory parameters of disease activity. It should be considered as a useful marker to detect active RA. IL-23 is involved in disease progression and bony erosions in patients with RA. Anti-IL-23 drugs could have a potential role in the treatment of RA.
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