Two-Component Dissipative Particle Dynamics Model of Red Blood Cells

Abstract

By modeling the lipid bilayer and the cytoskeleton separately, we applied a two-component Dissipative Particle Dynamics (DPD) red blood cell (RBC) model to simulate several in vitro and ex-vivo experiments. First, we validated our model by comparing simulation results with the experimental measurements in micropipette aspiration, membrane fluctuations, tank treading motions and bilayer tethering in a channel flow. We explored the effects of bilayer-cytoskeletal interaction properties such as elastic stiffness, viscous frictions and strength on these experiments and resolved several controversies on RBC mechanics in the literature. In addition, we simulated the ex-vivo perfusion of healthy and malaria-infected RBCs in human spleen by modeling the RBCs passing the inter-endothelial slits, and the predicted retention rates match the experimental measurement well. We also carried out systematic parametric studies on the critical conditions for RBCs to pass through the splenic slit. Our simulation results provide a comprehensive computational framework for understanding the roles of human spleen related to RBC-borne diseases such as malaria and hereditary spherocytosis.