[Expression of TNF receptors in rheumatoid arthritis and ankylosing spondylitis]

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 (SMNC) of patients with rheumatoid arthritis and spondylarthropathies express p75 TNF receptors in all cases, whereas SMNC of patients with traumatic synovitis do not. In 4/9 patients with rheumatoid arthritis and in 6/11 patients with spondylarthropathies SMNC also expressed the p55 TNF receptor. Differential analysis of lymphocytes and monocytes/macrophages revealed that both predominantly expressed the p75 TNF receptor. The highest concentrations of both soluble TNF receptors which may act as TNF antagonists were found in synovial fluids of rheumatoid arthritis patients.