SOLUBLE TUMOR-NECROSIS-FACTOR RECEPTOR IN SERUM OF PATIENTS WITH ARTHRITIS

Tumor necrosis factor (TNF) induces the production of two forms of sol uble receptor (p55 and p75) that are present in human serum at concent rations chat increase greatly ill inflammatory rheumatic disease, as w ell as varying among healthy individuals. The purpose of this study tv as to evaluate the usefulnesss of soluble TNF receptors in distinguish ing different forms of arthritis. Serum from patients with gout, rheum atoid arthritis, and osteoarthritis, and normal control subjects was a nalyzed for p55, p75, and TNF-alpha by enzyme-linked immunosorbent ass ay. Patients with gout had the highest level of soluble TNF receptor p 55, while there was no significant difference in the level of this rec eptor between rheumatoid arthritis patients and controls. Both rheumat oid arthritis and gout patients had higher soluble TNF receptor p75 le vels than osteoarthritis patients and control subjects, but there was no difference in the p75 level between rheumatoid arthritis and gout p atients. Osteoarthritis patients had higher levels of p55 and lower le vels of p75 than control subjects. The level of TNF-alpha in rheumatoi d arthritis patients was higher than in osteoarthritis patients, gout patients, and control subjects. Determination of soluble TNF receptor levels, especially p55, might enable differentiation of rheumatoid art hritis from osteoarthritis and gout. The level of p75 cannot be utiliz ed to differentiate rheumatoid arthritis and gout, in contrast to the results of previous investigations.