Effect of Boundary Stiffness on Contractility Profile of Valvular Interstitial Cells

Heart valve disease leads to approximately 300,000 heart valve replacement surgeries each year worldwide. Valvular interstitial cells (VICs) are believed to play a vital role in the repair of heart valves and also most disease processes. VICs synthesize, remodel, and repair the ECM; however, when VICs excessively differentiate to the highly contractile and synthetic myofibroblast phenotype, valvular fibrosis may ensue. Elevated mechanical stress triggers the differentiation of VICs into myofibroblasts. Transforming growth factor beta-1 (TGF-β1) is also critical for the formation of thicker stress fibers positive for α-smooth muscle actin (α-SMA), the defining characteristic of myofibroblasts.