Numerical algorithms to predict cellular traction forces

Description

Recent developments in heart valve tissue engineering have heightened the need for understanding and controlling cellular traction forces. Contractile cells are known to exert forces to their surroundings along the direction of actin stress fibers, which are acto-myosin bundles present in this kind of cells. These forces can possibly lead to unwanted leaflet retraction, with consequent valvular regurgitation. On the other hand, they can also influence the architecture of collagen fibers, which are very important for the mechanical properties and functionality of tissue-engineered heart valves. For these reasons, numerous computational models have been proposed to predict the remodeling of stress fibers, quantify their exerted stress, and ultimately determine its effects on the collagen fiber architecture and tissue-engineered constructs (Loerakker et al. 2014, Obbink-Huizer et al. 2014). However, coupling computational models for stress fiber and collagen remodeling can lead to excessive computational costs to run the simulations. Recently, a numerical algorithm has been proposed to efficiently perform this coupling (Ristori et al. 2016). This numerical algorithm enabled the simulation of tissue-engineered heart valves when exposed to cyclic mechanical stimuli (Loerakker et al. 2016). Nevertheless, the relationship between the parameters characterizing the remodeling and the performance of the numerical algorithm has not been studied yet.

References

• Loerakker S, Obbink-Huizer CWJ & Baaijens FPT (2014). A physically motivated constitutive model for cell-mediated compaction and collagen remodeling in soft tissues. Biomechanics and Modeling in Mechanobiology.
• Obbink-Huizer C, Oomens CWJ, Loerakker S, Foolen J, Bouten CVC & Baaijens FPT (2014). Computational model predicts cell orientation in response to a range of mechanical stimuli. Biomechanics and Modeling in Mechanobiology.
• Ristori T, Obbink-Huizer C, Oomens CWJ, Baaijens FPT, Loerakker S (2016). Efficient computational simulation of actin stress fiber remodeling. CMBBE.
• Loerakker S, Ristori T & Baaijens FPT (2016). A computational analysis of cell-mediated compaction and collagen remodeling in tissue-engineered heart valves. J Mech Behav Biomed Mater.