OBJECTIVE:
Characterize biomarkers measuring extracellular matrix turnover of inflamed osteoarthritis synovium.

METHODS:
Human primary fibroblast-like synoviocytes and synovial membrane explants (SMEs) treated with various cytokines and growth factors were assessed by C1M, C3M, and acMMP3 in the conditioned medium.

RESULTS:
TNFα significantly increased C1M up to seven-fold (p = 0.0002), C3M up to 24-fold (p = 0.0011), and acMMP3 up to 14-fold (p < 0.0001) in SMEs. IL-1β also significantly increased C1M up to five-fold (p = 0.00094), C3M four-fold (p = 0.007), and acMMP3 18-fold (p < 0.0001) in SMEs.

CONCLUSION:
The biomarkers C1M, C3M, and acMMP-3 were synovitis biomarkers ex vivo and provide a translational tool together with the SME model.