Circulating lnterleukin-16 in Systemic Lupus Erythematosus and Juvenile Rheumatoid Arthritis

Abstract

IL-16 originally named lymphocyte chemoattractant factor is a CD8+ T cell derived cytokine (also produced by monocytes, oesinophils, respiratory epithelium, fibroblasts and other cells). that induces chemotaxis of CD4 + T cells, monocytes and eosinophils. Besides its chemotactic activity, this cytokine also induces T cell activation (shown as induction of expression of IL-2R, HLA class II molecules on CD/ T cells) and aneryg (shown as suppression of MLR and decline in antigen induced proliferation of CD/ T cells) T cell abnormalities induced by IL-16 are also observed in lymphocytes in patients with SLE.

lL- I 6 was found to be significantly elevated in synovial fluid from patients with rheumatoid arthritis. The unique property of IL- I 6 to bind to CD4 molecule exerting both stimulating and inhibitory effects on T cell activation may explain the discrepancy between large number of infiltrating T cells in synovial membrane and lack of T cell derived cytokines in RA- SF and may add to our understanding of pathophysiological findings. Our study aimed at determining serum JL-16 level in SLE & JRA patients, its correlation with clinical manifestations and laboratory investigations, its possible role in the pathogenesis of these two autoimmune diseases and its possible relationship with disease activity. Patients included in this study were attending regularly

The Allergy and Immunology Clinic, Children's Hospital, Ain