Sohrabi Salman, Liu Yaling
Department of Mechanical Engineering & Mechanics.
Bioengineering Program, Lehigh University, Bethlehem, PA, USA.
Artif Organs. 2017 Sep;41(9):E80-E91. doi: 10.1111/aor.12832. Epub 2017 Jan 3.
A novel model is presented to study red blood cell (RBC) hemolysis at cellular level. Under high shear rates, pores form on RBC membranes through which hemoglobin (Hb) leaks out and increases free Hb content of plasma leading to hemolysis. By coupling lattice Boltzmann and spring connected network models through immersed boundary method, we estimate hemolysis of a single RBC under various shear rates. First, we use adaptive meshing to find local strain distribution and critical sites on RBC membranes, and then we apply underlying molecular dynamics simulations to evaluate damage. Our approach comprises three sub-models: defining criteria of pore formation, calculating pore size, and measuring Hb diffusive flux out of pores. Our damage model uses information of different scales to predict cellular level hemolysis. Results are compared with experimental studies and other models in literature. The developed cellular damage model can be used as a predictive tool for hydrodynamic and hematologic design optimization of blood-wetting medical devices.
提出了一种新模型,用于在细胞水平上研究红细胞(RBC)溶血。在高剪切速率下,红细胞膜上会形成孔隙,血红蛋白(Hb)通过这些孔隙泄漏出去,导致血浆中游离Hb含量增加,从而引发溶血。通过浸入边界法将格子玻尔兹曼模型和弹簧连接网络模型耦合,我们估计了单个红细胞在不同剪切速率下的溶血情况。首先,我们使用自适应网格划分来找到红细胞膜上的局部应变分布和关键部位,然后应用基础分子动力学模拟来评估损伤。我们的方法包括三个子模型:定义孔隙形成标准、计算孔径以及测量Hb从孔隙中的扩散通量。我们的损伤模型利用不同尺度的信息来预测细胞水平的溶血。将结果与实验研究以及文献中的其他模型进行了比较。所开发的细胞损伤模型可作为一种预测工具,用于对血液接触型医疗设备进行流体动力学和血液学设计优化。