Séance Séminaire

Séminaire des Doctorant·e·s

Impact of the membrane viscosity on red blood cell's behaviour.

Red blood cell's deformability could be used as a biomarker for diseases like malaria, sickle cell anemia or diabetes. Currently, it is not commonly measured during haematologic tests because of its complexity to fully describe it. Common tests only measure basic informations such as cell volume or number of cell in a sample. Those datas only does not accurately describe the full red blood cell's deformability. However, the importance of deformability on the measured signal is a well-known phenomenon. So the main goal of this project is to enable access of more information during haematology test in order to obtain a better deformability quantification. Yales2bio is a very valuable tool to study red blood cell's deformability. Its red blood cell's model, using immersed boundary method (IBM), has already been validated on numerous cases and is state of the art. In this current model, red blood cell's membrane follows an hyperelastic behaviour law (the Skalak behaviour law) for the local mechanical aspect. Some other forces as curvature forces are added to reproduce macro scale response of the membrane. However, an aspect that is not reproduced in the current model is the dissipation caused by the membrane deformation itself. Since 1987, we know that red blood cell's membrane follow a viscoelastic behaviour law. By implementing only the hyperelastic part of the membrane behaviour, some configurations are causing non realistic results. For exemple, tank treading configurations of only hyperelastic membrane leads to have higher membrane tank treading frequency than in reality. The main goal of my thesis is to study impact of the addition of a local dissipative part inside the membrane on the whole red blood cell behaviour. This presentation will be an introduction to viscoelasticity phenomenon, red blood cell behaviour and IBM techniques.