A physical description of the adhesion and aggregation of platelets

TL;DR

This study combines in-vitro experiments and numerical modeling to better understand platelet adhesion and aggregation during clot formation, highlighting the roles of blood albumin and shear-induced diffusivity.

Contribution

It introduces a comprehensive 3D model accounting for activated and non-activated platelets, improving understanding of the physical mechanisms behind platelet aggregation.

Findings

Blood albumin limits platelet adhesion and aggregation.

Shear-induced diffusivity is underestimated in previous models.

Simulations align well with experimental observations.

Abstract

The early stages of clot formation in blood vessels involve platelets adhesion-aggregation. Although these mechanisms have been extensively studied, gaps in their understanding still persist. We have performed detailed in-vitro experiments and developed a numerical model to better describe and understand this phenomenon. Unlike previous studies, we took into account both activated and non-activated platelets, as well as the 3D nature of the aggregation process. Our investigation reveals that blood albumin is a major parameter limiting platelet adhesion and aggregation. Our results also show that the well accepted Zydney-Colton shear-induced diffusivity is much too low to explain the observed deposition rate. Simulations are in very good agreement with observations and provide quantitative estimates of the adhesion and aggregation rates that are hard to measure experimentally.