Numerical Method And Simulation Of Amoeba Cell Migration

The cell migration of the amoeba migration pattern is accompanied by the entire life process of the organism,whether it is the development of the embryo or the occurrence of disease,it is inseparable from the cell migration behavior.The main feature of the amoeba migration pattern is the extension of the bleb pseudopod,and the cell body is translocated through the generation of blebs to carry out the migration behavior.Therefore,the occurrence and change of bleb morphology is an important mechanism of amoeba cell migration pattern.At present,by partially separating the cell membrane from the cortex and performing biochemical treatment on the cortex,the formation of blebs can be observed experimentally,but the mechanical mechanism that affects the size and shape of such blebs needs further study.On the basis of previous studies,this article first established a two-dimensional fluid-solid coupling cell model,which consists of cell membrane,cortex and cytoplasm;and then,change the key variables that affect the mechanical properties of the cell,analyze the reliability and rationality of the cell model;finally,analyze and study the parameters related to the blebs protruding from the cell.The main research content of this article:(1)A two-dimensional fluid-solid coupling cell model was established.The model consisted of a linear elastic cell membrane,a cortex,and a linear elastic link between the cell membrane and the cortex and the incompressible Newtonian fluid cytoplasm.The immersion boundary method is used to deal with the fluid-solid coupling problem,and the algorithm of the solid structure of the cell membrane and cortex is analyzed and improved.(2)Analyze the reliability and rationality of the cell model through the two conditions of the cell without bleb extension and with bleb extension.When the cells are free of blebs,by changing the viscosity of the cytoplasm,the damping coefficient of the cortex,the elastic modulus of the cell membrane and the corte,the changes of the flow rate and pressure inside and outside the cell,and the shape of the cell are analyzed;the local cell membrane and the cortex are analyzed.The link between them is broken,so that the cells extend out the bleb,and then by changing the size of the arc and the local cortex damping coefficient,observe the velocity and pressure of the flow field inside and outside the cells,and the changes in bleb morphology.All proved the reliability and rationality of this model.(3)Study the relationship between the bleb shape and the arc size of the broken link area and the change of the local cortex damping coefficient.By changing the arc of the broken link area and the local damping coefficient of the cortex,different forms of blebs are obtained.The process of cell shape change,as well as the change and influence of cell membrane and cortex tension during the change process.By observing the length and area changes of the bleb,this article explores the velocity of the bleb and its interaction with the cell body velocity,and compare the measurable experimental results with the numerical results in this paper.The model established in the paper contains the solid-like mechanical properties and hydrolike mechanical properties of the cells,which can more realistically simulate the mechanical phenomena of the cells.It is helpful to study the effect of changing the parameters such as the over-fracture arc and the local cortex damping coefficient simulation on the bleb shape.The indepth understanding of the formation mechanism of bleb pseudopods of the amoeba cell migration pattern also shows that the numerical method is effective for learning the characteristics of blebs.