Laboratory for Red Cell Rheology, Krummer Weg 20, 52134 Herzogenrath, Germany.
Biomolecules. 2023 Jan 9;13(1):130. doi: 10.3390/biom13010130.
The membrane of the human red cell consists of a lipid bilayer and a so-called membrane skeleton attached on the cytoplasmic side of the bilayer. Upon the deformation of red cells, energy is dissipated in their cytoplasm and their membrane. As to the membrane, three contributions can be distinguished: (i) A two-dimensional shear deformation with the membrane viscosity as the frictional parameter; (ii) A motion of the membrane skeleton relative to the bilayer; (iii) A relative motion of the two monolayers of the bilayer. The frictional parameter in contributions (ii) and (iii) is a frictional coefficient specific for the respective contribution. This perspective describes the history up to recent advances in the knowledge of these contributions. It reviews the mechanisms of energy dissipation on a molecular scale and suggests new ones, particularly for the first contribution. It proposes a parametric fitting expected to shed light on the discrepant values found for the membrane viscosity by different experimental approaches. It proposes strategies that could allow the determination of the frictional coefficients pertaining to the second and the third contribution. It highlights the consequences characteristic times have on the state of the red cell membrane in circulation as well as on the adaptation of computer models to the red cell history in an in vitro experiment.
人类红血球的膜由一个脂质双层和一个所谓的膜骨架组成，附着在双层的细胞质侧。在红血球变形时，能量会在它们的细胞质和膜中耗散。就膜而言，可以区分出三个贡献：（i）具有膜粘性作为摩擦参数的二维剪切变形；（ii）膜骨架相对于双层的运动；（iii）双层的两个单层之间的相对运动。贡献（ii）和（iii）中的摩擦参数是各自贡献的特定摩擦系数。本视角描述了这些贡献的知识的最新进展。它回顾了分子尺度上的能量耗散机制，并提出了新的机制，特别是对于第一个贡献。它提出了一个参数拟合，预计可以阐明不同实验方法发现的膜粘性的差异值。它提出了可以确定与第二和第三个贡献相关的摩擦系数的策略。它强调了特征时间对循环中红血球膜状态以及对体外实验中红血球历史的计算机模型适应性的影响。
