Matrix metalloproteinase-3 serum levels are correlated with disease activity and predict clinical response in rheumatoid arthritis

OBJECTIVE: To demonstrate that serum matrix metalloproteinase-3 (MMP-3) is a
variable associated with disease activity and with the response to treatment in
rheumatoid arthritis (RA). METHODS: Serum MMP-3 levels were measured and compared
to biological and clinical disease activity variables in 20 patients with active
RA assessed serially during a one year prospective open label trial with
methotrexate or tenidap. RESULTS: MMP-3 levels were significantly correlated with
C-reactive protein (CRP) and interleukin 6 serum levels as well as with the
disease activity score (DAS), not only at start in untreated patients but also
during the 12 month followup period in both treated groups. Early changes (after
0.5, 1, 2, or 3 months) in MMP-3 levels were significantly associated with change
in DAS observed 4 to 6 months later. CONCLUSION: In addition to CRP, a systemic
marker of inflammation, serum MMP-3 may serve as a consistent synovial derived
marker of RA disease activity, early changes of which predict disease outcome.