Figure 3. Effects of R667 on the expression of MMPs and TIMPs by HTFs. Cells were cultured in collagen gels for 3 days in the absence or presence of transforming growth factor-β1 (TGF-β1; 1 ng/ml) and in the presence of the indicated concentrations of R667. A: The culture supernatants were then either subjected to immunoblot analysis with antibodies to matrix metalloproteinase-1 (MMP-1) and to MMP-3 or analyzed with gelatin zymography for detection of pro and active forms of MMP-2. B: The culture supernatants were also subjected to immunoblot analysis with antibodies to tissue inhibitor of metalloproteinase-1 (TIMP-1) and to TIMP-2. All data are representative of three independent experiments.