Cytokine production by peripheral blood mononuclear cells from patients with juvenile idiopathic arthritis

Abstract

Juvenile idiopathic arthritis (JIA) is a chronic inflammatory arthritis of childhood characterized by synovitis and systemic features. The major players in the pathogenesis are T cells, macrophages and B cells. Cytokines are glycoproteins secreted from inflammatory cells like, activated T cells and macrophages. They are essentially of two varieties, pro-inflammatory (IL-1, IL-6, TNF-alpha, IL-8) or anti-inflammatory (IL-4, IL-10, IL-1 receptor antagonist). Cytokines are instrumental in regulating the magnitude, nature and duration of inflammatory response in arthritis. In adult rheumatoid arthritis (RA) pro-inflammatory cytokines IL-6, TNF-alpha and IL-1 have a major role in pathogenesis of synovitis(1). In contrast to adult RA, JIA is a heterogeneous disease with many distinct subsets. Systemic onset disease has marked systemic manifestations like fever, rash, hepato-splenomegaly with mild arthritis whereas polyarticular disease has persistent inflammatory arthritis involving more than 4 joints with mild systemic manifestations(2). The cytokines involved in the pathogenesis of JIA as a whole and in different subsets are still being investigated. Serum IL-1 and IL-6 levels are increased in patients with JIA in majority of the studies(3-5). We evaluated the production of other pro-inflammatory cytokines from peripheral blood mononuclear cells of patients with systemic onset and polyarticular form of JIA. Oligoarticular form was not included as they have a limited systemic response.