A physical description of the adhesion and aggregation of platelets

Abstract

The early stages of clot formation in blood vessels involve platelet adhesion–aggregation. Although these mechanisms have been extensively studied, gaps in their understanding still persist. We have performed detailed in vitro experiments, using the well-known Impact-R device, and developed a numerical model to better describe and understand this phenomenon. Unlike previous studies, we took into account the differential role of pre-activated and non-activated platelets, as well as the three-dimensional nature of the aggregation process. Our investigation reveals that blood albumin is a major parameter limiting platelet aggregate formation in our experiment. Simulations are in very good agreement with observations and provide quantitative estimates of the adhesion and aggregation rates that are hard to measure experimentally. They also provide a value of the effective diffusion of platelets in blood subject to the shear rate produced by the Impact-R.

Parameter Estimation of Platelets Deposition: Approximate Bayesian Computation With High Performance Computing

“…One of the main intuition is that the values of these parameters (e.g., adhesion and aggregation rates) are precisely the information needed to assess various possible pathological situations and quantify their severity regarding CVD. Further, it was shown in Chopard et al ( 2017 ) that, by hand-tuning the parameters of the mathematical model, the deposition patterns observed for a set of healthy volunteers in the Impact-R can be reproduced.…”

“…Hence, the challenge is to find parameters connecting the dynamic processes of adhesion and aggregation of platelets to the data collected from the individual patients . Recently, by combining digital holography microscopy (DHM) and mathematical modeling, (Chopard et al, 2015 ; Boudejltia et al, 2015 ; Chopard et al, 2017 ) provided a physical description of the adhesion and aggregation of platelets in the Impact-R device. A numerical model is developed that quantitatively describes how platelets in a shear flow adhere and aggregate on a deposition surface.…”

“…Further they are also incapable to consider inter-individual variability. A physical description of platelets deposition was introduced recently in Chopard et al ( 2017 ), by integrating fundamental understandings of how platelets interact in a numerical model, parameterized by five parameters. These parameters specify the deposition process and are relevant for a biomedical understanding of the phenomena.…”

Spherization of red blood cells and platelets margination in COPD patients

“…The discrepancy between the results can be explained, given that the coarse-grained stochastic model is based on parameters that are "trained" based on specific patient data. Considering that there is a new set of experiments with potential differences to the ones of Chopard et al7 (different patients),…”

Lattice Boltzmann method for modelling of biological phenomena

“…4. Indeed, the hemodynamic and the biological parameters are varying [19] [20] [26] [27] [28] with the successive growth of the thrombus (see Fig. 5).…”