Modeling receptor-ligand mediated adhesion in nanoindentation of cells

Abstract

The specific adhesion mediated by receptor-ligand binding in the nanoindentation of cells was studied by using a continuum-kinetics approach. It was found that the adhesion force only causes a shift to the indentation loading curve, whereas the unloading curve is tilted downward by the adhesion force, resulting in a hysteresis. Parametric studies were conducted to investigate how experimental conditions influence the adhesion force. It was found that the maximum adhesion force is sensitive to the geometry of the indenter but insensitive to the indentation depth and the mechanical properties of cells. It was also shown that the dependence of the adhesion force on the loading and unloading rates is controlled by the association rate of the receptorligand binding, leading to three well-defined regimes. © 2007 Materials Research Society.