Figure 1.

TGF-β₁ and CTGF stimulated fibroblast-mediated collagen matrix contraction. Fibroblast-populated collagen gel areas, measured in pixels, are shown after 3 days of culture in the presence of concentrations of TGF-β₁ or CTGF. Serum-free medium and medium containing 10% (v/v) serum were used as negative and positive controls, respectively. Both TGF-β₁ and CTGF stimulated contraction in a concentration-dependent manner. The error bars represent the SEM. The asterisk indicates a significant difference (P < 0.05) from the serum-free control.