EXPRESSION OF TNF RECEPTORS IN RHEUMATOID -ARTHRITIS AND SPONDYLARTHROPATHIES

Tumor necrosis factor is an important mediator of the pathophysiologic events in synovitis. The expression of the p75 and p55-TNF-receptors in rheumatic diseases was investigated. Synovial mononuclear cells (SM NC) of patients with rheumatoid arthritis and spondylarthropathies exp ress p75 TNF receptors in all cases, whereas SMNC of patients with tra umatic synovitis do not. in 4/9 patients with rheumatoid arthritis and in 6/11 patients with spondylarthropathies SMNC also expressed the p5 5 TNF receptor. Differential analysis of lymphocytes and monocytes/mac rophages revealed that both predominantly expressed the p75 TNF recept or. The highest concentrations of both soluble TNF receptors which may act as TNF antagonists were found in synovial fluids of rheumatoid ar thritis patients.