Molecularly based analysis of deformation of spectrin network and human erythrocyte

We examine the large deformation elastic response of the spectrin network in a human red blood cell (RBC) on the basis of molecular-level constitutive laws. These formulations are shown to be consistent with the predictions of continuum level models for the hyperelastic deformation of RBC, and are compared with recent experimental studies of whole-cell deformation using optical tweezers stretching. Implications of these analysis for extracting cell membrane and cytoskeleton response from whole-cell computational simulations of large deformation for realistic geometries of RBC spectrin network are described. Aspects of large deformation, such as the folding of cell wall during large deformation, are also examined. We also provide general scaling relationships and closed-form functions on the basis of which mechanical properties of RBCs can be extracted from optical tweezers experiments.