Objective: To determine whether plasma concentrations of stromelysin-1 and gelatinase A are increased in patients with various forms of arthritis.
Methods: A sensitive and specific sandwich enzyme linked immunosorbent assay (ELISA), which employs a murine monoclonal antibody and a rabbit polyclonal antibody to human stromelysin-1, was used to measure plasma stromelysin-1 in 53 healthy subjects, 113 patients with various forms of arthritis and connective tissue diseases, and 65 patients with cancer. Gelatinase A was also measured in these patients using specific polyclonal and monoclonal antibodies to gelatinase A in an ELISA:
Results: The plasma concentration of stromelysin-1 (X +/- SEM) was significantly increased (p < 0.001) in patients with rheumatoid arthritis (RA) (187 +/- 14 ng/ml) and systemic lupus erythematosus (SLE) (258 +/- 35 ng/ml) as compared to both healthy control subjects (50 +/- 4 ng/ml) or patients with cancer (61 +/- 20 ng/ml). Plasma stromelysin-1 was also significantly increased in smaller groups of men with osteoarthritis (OA) and gout. In contrast, plasma concentrations of gelatinase A were not significantly increased in patients with RA, OA or gout. In healthy subjects, the concentration of stromelysin-1 was significantly higher in men than women. No correlation was noted between plasma stromelysin-1 levels and age.
Conclusion: The detection of elevated plasma levels of stromelysin-1 in patients with RA is consistent with increased stromelysin-1 concentrations in inflamed synovial tissues in this disease. The origin of increased plasma stromelysin-1 in SLE is speculative. Measurement of plasma stromelysin-1 may be useful in the diagnosis and management of patients with various forms of arthritis.