Background Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by the production of a vast array of auto-reactive antibodies and the formation of immune complexes causing tissue and organ damage .
Objectives To assess serum levels of interleukin IL-18 (IL-18) and interleukin-10 (IL-10) levels in a population of Egyptian patients with SLE and study their relation to disease activity in terms of SLEDAI score.
Methods Thirty patients with SLE and twenty healthy controls were investigated in this study. Patients were selected from outpatient clinics of the Rheumatology Department of Faculty of Medicine, Sohag University between December 2011 and December 2012. The study included thirty patients (female/male=27/3) with the established diagnosis of SLE classification done according to the American College of Rheumatology (ACR) criteria were included in the study . Their ages ranged from 25 to 44 years. Twenty age and sex matched normal healthy individuals (female/male =17/3) were included as a control group. Their ages ranged from 23 to 42 years with a mean of 32.67±2.1years. Informed consents were taken from the patients and the study was approved by the ethics committee of the research organization. The serum IL-18 & IL-10 levels were determined using enzyme linked immunosorbent assay (ELISA) and their correlations with the disease activity were measured using the SLE Disease Activity Index (SLEDAI) and laboratory parameters including, erythrocyte sedimentation rate, anti-double stranded-DNA antibody, Complement 3 (C3) and Complement 4 (C4) levels were analyzed.
Results The serum IL-18 and serum IL-10 levels were significantly higher (mean values 1770.2±360.4 pg/ml, 842.65±315.37 pg/ml for IL-18 and IL-10 respectively) in SLE patients compared to the controls (110.65±30.37 pg/ml, 76±14.2 pg/ml respectively, p<0.001). The increase in serum levels of IL- 18 and IL- 10 directly and significantly correlated with each other (r =0.404, P=0.037). Furthermore, such an increase in the levels of these two cytokines showed a highly significant positive correlation to the SLEDAI scores [Tables 1 and 2]and anti-ds DNA in the studied patients (p<0.001).
Conclusions The study emphasizes that there exists an up-regulated pro as well as anti-inflammatory responses in patients with active SLE, however the anti-inflammatory response appears to be insufficient to suppress the active disease. Identifying the exact contribution of the currently studied cytokines might provide future insights for targeted therapeutic strategies in SLE.
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Disclosure of Interest None declared