Recombinant human decorin inhibits TGF-β1-induced contraction of collagen lattice by hypertrophic scar fibroblasts

Decorin was reported to bind transforming growth factor-beta (TGF-β1) and neutralise some of its activity as a key regulator of wound contraction and hypertrophic scar formation. In this study, we investigated whether recombinant human decorin affected TGF-β1-induced fibroblast contractile activity, by using fibroblast-populated collagen lattice with decorin added to the collagen gel. Hypertrophic scar fibroblasts showed greater basal contraction of collagen gels than normal fibroblasts, and the addition of TGF-β1 significantly enhanced this. Decorin inhibited both the basal and TGF-β1-enhanced contraction of collagen gel by both normal and hypertrophic scar fibroblasts. Decorin also inhibited TGF-β1-induced α-smooth muscle actin (α-SMA), plasminogen activator inhibitor-1 (PAI-1) protein and mRNA expressions in normal and hypertrophic scar fibroblasts. These results suggest that decorin may have therapeutic potential for excessive skin contraction as observed in hypertrophic scarring.