The Effects of Biological Agents Therapy (Etanercept &Rituximab) Compared with Disease Modifiying Anti-Rheumatic Drugs (DMARDs) on the Serum Level of IL-17A and Resistin in Rheumatoid Arthritis Patients

Rheumatoid arthritis (RA) represents the most common form of chronic inflammatory joint disease leading to cartilage and bone destruction, It affects approximately 1-2 % of world’s population. The inflammatory process causes diffuse thickening and hyperplasia of the joint. It is infiltrated with numerous inflammatory cells that produce several pro-inflammatory mediators. The blockade of these mediators has already led to the development of highly efficient biological agents to treat this disease. Although therapies with traditional disease-modifying antirheumatic drugs and biological agents that target specific molecular and cellular disease mediators have improved outcomes, substantial disease activity persists in many patients. This study was carried out to investigate the role of Interleukin-17A (IL-17A) and resistin in pathogenesis of rheumatoid arthritis and to compare between the levels of IL-17A and resistin in Rheumatoid Arthritis patients with and without the use of the RA treatment. Moreover, this study was conducted to evaluate the impact of biological agents therapy on IL-17A and resistin in comparison to classical disease modifying anti-rheumatic drugs in patients with rheumatoid arthritis. A total of 120 patients with rheumatoid arthritis were studied. Their ages ranged from 20-70 years with a mean age of 46.55±1.09 years. The apparently healthy volunteers consisted of 25 individuals who were considered as control. The patients were divided into four groups: Group I consisted of 30 patients without treatment, while group II consisted of 30 patients who received methotrexate. Group III included 30 patients who received Etanercept (anti-tumor necrosis factor alpha) and Finally, Group IV has 30 patients received Rituximab (anti-CD20). Blood samples were collected from patients and controls to assess Erythrocyte Sedimentation Rate (ESR) and serum levels of C-reactive protein (CRP), Rheumatoid Factor (RF), IL-17A and Resistin. C-reactive protein and rheumatoid factor were estimated by agglutination test, whereas IL-17A and resistin were measured by means of enzyme-linked immune-sorbent assay. The current results revealed that serum levels of C-reactive protein and rheumatoid factor were significantly higher in RA patients than in healthy controls (P<0.001). Moreover, The level of IL-17A was significantly higher in group I patients than in healthy controls, and each of group III, group IV of patients (P<0.001), but there was no significant difference between group I and II (P>0.05). Significant elevation in resistin level was found in group I of patients than in healthy controls and group III (P<0.001), while there is no significant differences between group I and each of group II and IV (P>0.05). Regarding correlation among different studied parameter in RA, the present study showed significant positive correlation between each of serum level IL-17, Resistin, ESR, CRP and RF, (P<0.001). These findings demonstrate that IL-17A may has a significant effect in the pathogenesis of rheumatoid arthritis and that its presence at high levels in the serum of patients inspite of using the biological therapy indicate the important role of IL-17A in the development of disease. In addition, The correlation between resistin and inflammatory markers gave additional support to that the increased resistin values in patients could be linked to the rheumatoid inflammation.