Tensegrity FE models of mechanical tests of individual cells

conference paper

English

The paper deals with computational finite element modelling of various mechanical tests carried out with individual cells. Our attention is focused on smooth muscle cells of the vascular wall. A changed loading of the vascular wall initiate a response of these cells in the form of tissue remodelation. The increased load is supposed to initiate exoskeleton stiffening with the aim to bring the cell load back to the physiological values. To understand these processes, it is necessary to know the mechanical properties of the cell and to model its mechanical behaviour. In our contribution FE models of an individual smooth muscle cell are presented, at various levels of the cell structure: a) Cell as a homogeneous isotropic hyperelastic continuum. b) Cell model consisting of nucleus, sarcoplasm, cortex (modelled by shell elements on the cell surface) and endoskeleton (modelled as a simple tensegrity structure with 6 struts and 24 cables, all with linear elastic properties). c) Cell model with a more complex tensegrity structure representing the endoskeleton. A model of endoskeleton containing 30 struts and 60 cables has been proposed and tested. Simulation of tension tests and indentation tests (based on atomic force microscopy) using the above models will be presented in the paper. Attempts are made to identify the constitutive parameters of the models. In model a) an iterative identification of five parameters of the Mooney-Rivlin hyperelastic model was carried out. In models b) and c) the possibilities of identification of parameters are tested and the sensitivity of the results on the changes in elastic moduli of the individual components is investigated. Possibilities of creation of tensegrity models of the endoskeleton are also discussed.

Tensegrity, FE model, eucaryotic cell, cytoskeleton

BURŠA, J.; LEBIŠ, R.

2006

29. 7. 2006

European Society of Biomechanics

Munich, Germany

CD

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