Valtchanov Hristo, Cecere Renzo, Mongrain Rosaire
Department of Mechanical Engineering 1, McGill University, Quebec, Canada.
Division of Cardiac Surgery, McGill University Health Centre, Quebec, Canada.
Sci Rep. 2025 Jul 1;15(1):20698. doi: 10.1038/s41598-025-01344-0.
Modelling blood flow and particularly cellular damage induced by supra- and non-physiological blood-flow conditions is crucial when developing novel blood-exposed biomedical devices and treatments. Blood is composed of 30-50% red blood cells (RBCs) by volume, yet the mechanisms and effects of intercellular collisions are frequently neglected in red blood cell damage models. These effects are investigated by employing fully coupled 3D fluid structure-interaction simulations to simulate the collision processes in a Couette shear flow and to gauge their effect on the strain experienced by the RBC membrane as well as the transmembrane hemoglobin diffusion rate. Intercellular collisions are found to nearly double the membrane strain at hemolytic shear rates, with declining effect as the shear rate increases, and have a similar effect on sublethal hemoglobin diffusion. Viscoelastic simulations were conducted to examine the effect of incorporating membrane viscosity on the strain experienced by red blood cell membrane during collisions, and find minimal impact of incorporating viscoelasticity at high shear. Incorporating the effect of intercellular collisions is found to be a crucial factor for predicting stress-induced cellular damage under dynamic conditions.
在开发新型血液接触式生物医学设备和治疗方法时，对血流进行建模，尤其是对由超生理和非生理血流条件引起的细胞损伤进行建模至关重要。按体积计算，血液由30%-50%的红细胞（RBC）组成，但在红细胞损伤模型中，细胞间碰撞的机制和影响常常被忽视。通过采用完全耦合的三维流固相互作用模拟来研究这些影响，以模拟库埃特剪切流中的碰撞过程，并评估其对红细胞膜所经历的应变以及跨膜血红蛋白扩散速率的影响。发现在溶血剪切速率下，细胞间碰撞使膜应变几乎增加一倍，随着剪切速率增加，这种影响逐渐减弱，并且对亚致死性血红蛋白扩散有类似影响。进行了粘弹性模拟，以研究纳入膜粘度对碰撞过程中红细胞膜所经历应变的影响，发现在高剪切下纳入粘弹性的影响极小。发现纳入细胞间碰撞的影响是预测动态条件下应力诱导细胞损伤的关键因素。
