Geekiyanage N M, Sauret E, Saha S C, Flower R L, Gu Y T
School of Mechanical, Medical and Process Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), Brisbane, QLD, Australia.
University of Technology Sydney (UTS), Ultimo, NSW, Australia.
Biomech Model Mechanobiol. 2020 Oct;19(5):1827-1843. doi: 10.1007/s10237-020-01311-w. Epub 2020 Feb 25.
The red blood cell (RBC) deformability is a critical aspect, and assessing the cell deformation characteristics is essential for better diagnostics of healthy and deteriorating RBCs. There is a need to explore the connection between the cell deformation characteristics, cell morphology, disease states, storage lesion and cell shape-transformation conditions for better diagnostics and treatments. A numerical approach inspired from the previous research for RBC morphology predictions and for analysis of RBC deformations is proposed for the first time, to investigate the deformation characteristics of different RBC morphologies. The present study investigates the deformability characteristics of stomatocyte, discocyte and echinocyte morphologies during optical tweezers stretching and provides the opportunity to study the combined contribution of cytoskeletal spectrin network and the lipid-bilayer during RBC deformation. The proposed numerical approach predicts agreeable deformation characteristics of the healthy discocyte with the analogous experimental observations and is extended to further investigate the deformation characteristics of stomatocyte and echinocyte morphologies. In particular, the computer simulations are performed to investigate the influence of direct stretching forces on different equilibrium cell morphologies on cell spectrin link extensions and cell elongation index, along with a parametric analysis on membrane shear modulus, spectrin link extensibility, bending modulus and RBC membrane-bead contact diameter. The results agree with the experimentally observed stiffer nature of stomatocyte and echinocyte with respect to a healthy discocyte at experimentally determined membrane characteristics and suggest the preservation of relevant morphological characteristics, changes in spectrin link densities and the primary contribution of cytoskeletal spectrin network on deformation behaviour of stomatocyte, discocyte and echinocyte morphologies during optical tweezers stretching deformation. The numerical approach presented here forms the foundation for investigations into deformation characteristics and recoverability of RBCs undergoing storage lesion.
红细胞（RBC）的可变形性是一个关键方面，评估细胞变形特征对于更好地诊断健康和恶化的红细胞至关重要。有必要探索细胞变形特征、细胞形态、疾病状态、储存损伤和细胞形状转变条件之间的联系，以实现更好的诊断和治疗。首次提出了一种受先前红细胞形态预测和红细胞变形分析研究启发的数值方法，用于研究不同红细胞形态的变形特征。本研究调查了口形红细胞、盘状红细胞和棘状红细胞在光镊拉伸过程中的可变形性特征，并提供了研究红细胞变形过程中细胞骨架血影蛋白网络和脂质双层联合作用的机会。所提出的数值方法预测的健康盘状红细胞变形特征与类似的实验观察结果一致，并被扩展以进一步研究口形红细胞和棘状红细胞形态的变形特征。特别是，进行了计算机模拟以研究直接拉伸力对不同平衡细胞形态下细胞血影蛋白连接延伸和细胞伸长指数的影响，同时对膜剪切模量、血影蛋白连接延伸性、弯曲模量和红细胞膜 - 微珠接触直径进行了参数分析。结果与在实验确定的膜特性下实验观察到的口形红细胞和棘状红细胞相对于健康盘状红细胞更硬的性质一致，并表明在光镊拉伸变形过程中，口形红细胞、盘状红细胞和棘状红细胞形态保持了相关形态特征、血影蛋白连接密度发生了变化以及细胞骨架血影蛋白网络对变形行为起主要作用。这里提出的数值方法为研究经历储存损伤的红细胞变形特征和恢复能力奠定了基础。
