Th-17 related regulatory network in the pathogenesis of Arab patients with systemic lupus erythematosus and lupus nephritis

Aim: The present study aimed to identify the genes involved in the pathogenesis of systemic lupus erythematosus (SLE) in Arabs by investigating a panel of 84 genes related to the t helper (Th) 17-related regulatory network and to further explore the expression levels of serum interleukin (IL)-17A and IL-17F in a studied cohort. A comparative analysis of gene expression profile in SLE and lupus nephritis (LN) patients against that of healthy controls (HC) was performed. Method: A quantitative real-time polymerase chain reaction (PCR) (Th17 autoimmunity and inflammation) array analysis was performed in peripheral white blood cells of 66 SLE patients under specific medical treatment and 30 age/gender/ethnically matched healthy controls. Statistical analysis was carried out using the RT2 Profiler TM PCR Data Analysis tool. Results: The analysis of Th17 pathway revealed 14 genes (IL-17A, IL-17C, IL-17D, IL-17F, IL-18, IL-12RB2, IL-23R, CCL2, CCL20, CXCL5, MMP3, RORC, STAT4 and TRAF6) that are differentially expressed in SLE and HC (fold change [FC] < 2, P < 0.0006). No significant difference in expression profiles was observed between SLE and LN. A significant difference in serum concentration of IL-17A (P = 0.002) and IL-17F (P = 0.002) was observed between SLE (13.91 +/- 4.25) and LN (18.26 +/- 4.24). Conclusion: Our study is the first to investigate a panel of 84 genes related to Th17 regulatory pathway in Arab SLE subjects and the first to explore the effect of current immunosuppression regimens on Th17 regulatory pathway. It paves the way for understanding the etiology of SLE and autoimmune diseases in general.