Figure 3: Modulation of the TGF-β1-induced expression of MMPs. The mRNA and protein expression levels of MMP-3 (A, B), MMP-10 (C, D) and MMP-13 (E, F) were measured in MSC grown on different substrates as indicated. Cells were exposed to 10 ng/mL TGF-β1 for 24 h (black bars) or left untreated as controls (white bars). TGF-β1 elevated the expression of MMP-3, MMP-10, and MMP-13 in MSC independently of the substratum on which the cells were grown. The increase in MMP-3 and -10 transcript and protein amounts were lower in MSC incubated on col-1 than in MSC attached to plastic or laminin-111. The expression of MMP-13 was not affected by attachment to collagen. The results are depicted as mean ± SD of at least 4 independent experiments. Asterisks indicate significance (* p≤0.05 / ** p≤0.01) of activated cells vs. controls without TGF-β1 stimulation.