Systematic coarse-graining of spectrin-level red blood cell models

Area of Science:

• Biophysics
• Computational Biology
• Materials Science

Background:

• Red blood cell (RBC) mechanical properties are crucial for understanding diseases like malaria.
• Existing coarse-grained RBC models often struggle with accurate mechanical response prediction and model stability.
• Optical tweezers experiments provide valuable data for validating RBC mechanical models.

Purpose of the Study:

• To develop a rigorous procedure for deriving accurate coarse-grained red blood cell (RBC) models.
• To accurately predict the linear and nonlinear elastic properties of healthy and malaria-infected RBCs.
• To introduce a novel stress-free RBC model addressing limitations of existing approaches.

Main Methods:

• Semi-analytic theory for model derivation.
• Optical tweezers stretching experiments for validation.
• Dissipative particle dynamics for numerical implementation.

Main Results:

• The new model accurately matches experimental elastic properties of RBCs.
• It correctly predicts membrane Young's modulus, reducing prediction error by approximately 50% compared to previous models.
• The stress-free model ensures stable equilibrium shapes and robust mechanical property assessment, independent of initial mesh quality.

Conclusions:

• The developed coarse-grained RBC model offers a significant advancement in accurately simulating cellular mechanics.
• This model provides a reliable tool for studying RBC behavior in health and disease, particularly in malaria.
• The methodology is adaptable to various numerical techniques, broadening its applicability in computational biomechanics.