Efficiency of initiating cell adhesion in hydrodynamic flow

TL;DR

This study theoretically examines how shear flow influences the initial binding efficiency between receptor-coated spheres and ligand-coated walls, revealing key factors that optimize cell adhesion in blood flow.

Contribution

It introduces a theoretical model analyzing the effects of shear rate and receptor patch geometry on cell adhesion efficiency in flow conditions.

Findings

Binding efficiency increases with shear rate up to a saturation point.

Increasing receptor patch height significantly enhances binding.

Receptor patch size and number have limited effects beyond a threshold.

Abstract

We theoretically investigate the efficiency of initial binding between a receptor-coated sphere and a ligand-coated wall in linear shear flow. The mean first passage time for binding decreases monotonically with increasing shear rate. Above a saturation threshold of the order of a few 100 receptor patches, the binding efficiency is enhanced only weakly by increasing their number and size, but strongly by increasing their height. This explains why white blood cells in the blood flow adhere through receptor patches localized to the tips of microvilli, and why malaria-infected red blood cells form elevated receptor patches (knobs).