Fig. 6

Synovial fluid-induced matrix metalloproteinase (MMP) expression was suppressed by Toll-like receptor (TLR)-2 and myeloid differentiation factor 88 (MyD88) knockdown. a TLR-2 in chondrocytes was knocked down by small interfering TLR-2 (siTLR-2) transfection, after which cells were treated with sequentially diluted synovial fluid. MMP-1 and MMP-3 expression levels in culture media were determined using Western blot analysis. b The expression levels of MMP-13 in culture media were determined by enzyme-linked immunosorbent assay (ELISA). Data represent the means ± SD for triplicate experiments from three different donors. c MyD88 in chondrocytes was knocked down by small interfering MyD88 (siMyD88) transfection, after which cells were treated with sequentially diluted synovial fluid. MMP-1 and MMP-3 expression levels in culture media were determined using Western blot analysis. d The expression levels of MMP-13 in culture media were determined using ELISA. Control untreated with synovial fluid, control siRNA control small interfering RNA-transfected cells, siTLR-2 small interfering TLR-2 RNA-transfected cells, siMyD88 small interfering MyD88 RNA-transfected cells. Data represent the mean ± SD for triplicate experiments from three different donors. *P < 0.05, **P < 0.01, and ***P < 0.001 vs. control siRNA-transfected chondrocytes