Serum interleukins 2 and 10 in juvenile systemic lupus erythematosus: relation to disease activity

INTRODUCTION Juvenile systemic lupus erythematosus (j-SLE) is an autoimmune inflammatory disease that affects children ≤ 18 years. It represents 15–20% of all SLE patients. It is characterized by systemic inflammation and a wide spectrum of circulating autoantibodies due to dysfunctional immune regulation. 2 Interleukins have an important role in the pathogenesis of SLE and they are considered to be disease biomarkers because their levels vary with disease activity. So, they could be used as therapeutic targets. They are produced by T helper (Th) cells. IL-2 is a monomeric glycoprotein that is produced by Th1 and CD4+ T lymphocytes. It plays a critical role in immune homeostasis and regulation. Patients lacking IL-2 expression have defective immune responses. The induction of antiIL-2 autoantibodies and decreased its serum level may have a role in the occurrence of SLE activity. IL-10 is produced by regulatory Th cells (Treg), Th2, and CD8+ T lymphocytes. It plays an important role in B cell activation and autoantibody production. Also, it has direct inhibitory effects on the proliferation of CD4+ T cells and Th1 cytokines production such as IL2. IL-10 is defined as a potent stimulator of B lymphocytes and it stimulates the production of anti-DNA auto-antibodies in SLE patients. The overproduction of IL-10 may have a role in the occurrence of SLE activity. This study was conducted to evaluate serum levels of IL-2 and IL-10 and to calculate their ratio in relation to the disease activity in a group of children and adolescence with SLE.