Fibroblast-like synoviocytes from fluid and synovial membrane from primary osteoarthritis demonstrate similar production of interleukin 6, and metalloproteinases 1 and 3.

Objectives: The objective of the study was to compare the production of metalloproteinases (MMP)-1, -3 and interleukin (IL)-6 by fibroblast-like synoviocytes (FLS) derived from synovial fluid (FD-FLS), and FLS derived from synovial tissue (TD-FLS) of patients with primary osteoarthritis (OA). The more accessible FD-FLS could facilitate the study of the role of these cells in OA pathophysiology.

Methods: MMP-1, MMP-3, and IL-6 levels were measured in the supernatant culture at baseline and 22 hours after stimulation with TNF-α and IL-1 β.

Results: There was no difference at baseline between MMP-1, MMP-3 and IL-6 production by FD-FLS and TDFLS. Analogous to baseline, stimulation of FD-FLS and TD-FLS with IL-1β and TNF-α did not result in difference on MMP-3 and IL-6 production. However, TD-FLS produced more MMP-1 than FD-FLS after stimulation with IL-1β (p=0.01). Additionally, there was a positive correlation for production of MMP-1, MMP-3 and IL-6 between FD-FLS and TD-FLS (r=0.40 and p<0.0008; r=0.66 and p<0.0001; r=0.76 and p<0.0001, respectively). Supporting this statistical significant positive correlation, the Bland-Altman plotting, showed a homogeneous distribution of the values and low mean disagreement rates between all results of FD-FLS and TD-FLS (23.1%, 56.8% and 48.1%, respectively).

Conclusions: Our data demonstrated functional similarity between FD-FLS and TD-FLS and support the use of a more accessible source of FLS for the study of the pathogenesis of joint destruction and therapeutic targets in primary OA.