Circulating soluble tumour necrosis factor receptors in rheumatoid arthritis

ABSTRACT

Two types of tumur necrosis factor receptors, TNF-RI and TNF-RII, have been identified. It has been suggested that levels of soluble TNF receptors in the serum can serve as markers of disease activity in rheumatoid arthritis [RA]. This work was designed to measure the soluble TNF-RI and RII in serum of RA patients during disease activity and to find out if their levels reflect clinical response in these patients after methotrexate therapy for 24 weeks. This study was conducted on 30 patients with active RA and 16 healthy controls. The soluble TNF receptors were assayed before and after methotrexate therapy using ELISA technique. Our study revealed that the concentrations of soluble TNF-RI [P55] and RII [P75] were significantly higher in RA patients during disease activity compared to healthy controls [P<0.001 for each receptor]. After methotrexate therapy, a significant decrease in P55 sTNF-R concentration was associated with clinical improvement [P<0.001] while the decrease in P75 sTNFR concentration was found to be insignificant. We conclude that sTNF receptors [P55 and P75] serve as markers of disease activity in RA and we can consider P55 sTNF- R as a marker of clinical response and drug efficacy