Progressive detachment of cells from surfaces: a consequence of heterogeneous ligand populations or a multi-site binding equilibrium?

A multi-site binding equilibrium model is proposed to describe the effect of applied shear on the detachment of affinity adsorbed particles or cells from surfaces. Unlike earlier models used to describe this phenomenon the current approach considers the extent to which multiple interactions show surface cooperativity such that the attached fraction can be described in terms of a number of subpopulations linked via differing numbers of ligand/receptor interactions.