Fig. 1.

Illustration showing the appearance of the myofibroblast phenotype during normal repair conditions. Fully differentiated myofibroblasts possess stress fibres expressing α-smooth muscle actin (dotted lines) and secrete important amount of extracellular matrix (ECM). Pro-fibrotic cytokines such as transforming growth factor-β1, ECM components such as ED-A fibronectin and the mechanical microenvironment are all involved in myofibroblastic differentiation. Myofibroblasts are highly contractile cells that stiffen the ECM, leading to an activation of pro-fibrotic growth factors, further stimulating the activation of new myofibroblasts