A hyperelastic model for simulating cells in flow

Area of Science:

• Biophysics
• Biomaterials Engineering
• Computational Biology

Background:

• Cell damage during 3D bioprinting is a major challenge, leading to cell death and loss of functionality.
• This damage is linked to cell deformation caused by hydrodynamic stresses during the printing process.
• Understanding the mechano-elastic response of cells is critical for mitigating these issues.

Purpose of the Study:

• To develop and validate a numerical model for simulating biological cell deformation in arbitrary 3D flows.
• To accurately predict cell behavior under hydrodynamic stresses encountered during 3D bioprinting.
• To improve the fidelity and success rate of 3D bioprinting applications.

Main Methods:

• Modeling cells as elastic continua using the hyperelastic Mooney-Rivlin model.
• Employing force calculations on a tetrahedralized volume mesh.
• Integrating the cell deformation model into Lattice Boltzmann simulations via an Immersed-Boundary algorithm.

Main Results:

• Model calibration using FluidFM compression experiments on REF52 cells confirmed the necessity of all three Mooney-Rivlin parameters for large deformations (up to 80%).
• Validation against AFM experiments on endothelial cells and hydrogel particles demonstrated model accuracy.
• Simulations in linear shear flows showed excellent agreement with analytical calculations and prior simulation data.

Conclusions:

• The developed numerical model accurately simulates cell deformation in 3D flows, crucial for 3D bioprinting.
• The model's ability to capture large deformations and its validation provide a robust tool for bioprinting research.
• This work contributes to reducing cell damage and enhancing the functionality of 3D bioprinted constructs.