Fig. 5. MMP-dependent activation of TGFβ in response to wounding in CD44WT fibroblasts. Levels of total and active TGFβ in conditioned media from unwounded and wounded CD44WT and CD44KO fibroblasts, treated with or without the MMP inhibitor GM6001 were determined after 24 hours. (A) CD44WT fibroblasts, unwounded vs wounded, and in the absence or presence of GM6001 (1 µM). (B) CD44KO fibroblasts, unwounded vs wounded, and in the absence or presence of GM6001 (1 µM). Values were normalized to protein concentration. Cell viability and total levels of TGFβ were comparable between CD44WT and CD44KO fibroblasts under each condition. Data are presented as an average of the percentage of active TGFβ (active TGFβ divided by total TGFβ x 100), as measured in three independent experiments. Within each experiment, the conditions were applied in triplicate and also assayed in triplicate. Error bars represent s.e.m.