VISCOELASTICITY OF BLOOD CELLS

提出了一个多方面的研究来测量粘性耗散。 (粘度)在红血球和红细胞膜中。此外，它是 建议研究细胞和膜粘度在调节细胞和膜黏度中的作用 膜蛋白的横向扩散，个体的变形性 细胞在毛细管流中的流动和浓缩液的体流变特性 细胞悬浮液。 测定红细胞膜和红细胞膜的粘性 使用微操作和微管吸引器完成 产生明确定义的细胞变形和流动速率的技术 和膜。这些流动包括(1)连续的、轴对称的流动 从球形细胞体到弹性圆柱形细胞膜 链或“系绳”，(2)由两条链融合而产生的轴对称流动 细胞(请注意，这个特殊的实验允许几乎同时进行 粘度和扩散系数的测量)，(3)表面剪切流 通过将红细胞从细长的形状恢复到 双凹圆盘和(4)在展开过程中产生的血红蛋白流动。 红细胞从小的(3-4微米直径)吸管中排出后的红细胞。 将使用连续荧光光漂白来测量 荧光膜颗粒从细胞扩散时的扩散系数 身体到系绳。两个细胞融合后的扩散率将 通过跟踪荧光标记膜的运动来研究 其中一个细胞膜上的蛋白质在它们扩散到 赤道线。最后，膜和细胞粘度在 管理细胞的变形性将通过研究 红细胞通过单孔的流动和通过测量体积 微升填充细胞悬浮液的流变性 在磁声粘度计中。 从根本上讲，膜粘度是一种 膜分子的集体相互作用。因此，对膜的研究 粘度提供了对膜结构的洞察力。从一个实用的 观点认为，膜表面的粘性耗散影响其 对传染病、免疫反应和溶血的反应 现象。此外，红细胞对快速形状的反应能力 在循环中移动时的变化受以下因素影响和控制 膜的粘性。所有这些因素(膜和 细胞粘度、膜扩散率和细胞变形性)将 学习。

A multifaceted study is proposed to measure the viscous dissipation (viscosity) in red cells and red cell membrane. In addition, it is proposed to study the role of cell and membrane viscosity in governing the lateral diffusion of membrane proteins, the deformability of individual cells in capillary flow and the bulk rheological properties of concentrated cell suspensions. Measurement of the viscous properties of red cells and red cell membrane is accomplished by using micromanipulation and micropipet aspiration techniques to produce well-defined rates of deformation and flow of cells and membrane. These flows include (1) the continuous, axisymmetric flow of membrane from a spherical cell body to an elastic, cylindrical membrane strand or "tether", (2) the axisymmetric flow produced by the fusion of two cells (note that this particular experiment permits the nearly simultaneous measurement of viscosity and diffusivity), (3) the surface shear flow produced by the recovery of a red cell from an elongated shape to a biconcave disk and (4) the hemoglobin flow produced during the unfolding of a red cell after it is ejected from a small (3-4 Mum diameter) pipet. Continuous fluorescence photobleaching will be used to measure the diffusivity of fluorescent membrane particles as they diffuse from cell body to tether. The diffusivity subsequent to the fusion of two cells will be studied by following the motion of fluorescently tagged membrane proteins in the membrane of one of the cells as they diffuse across an equatorial line. Finally, the role of membrane and cellular viscosity in governing the deformability of cells will be determined by studying the flow of red cells through a single pore and by measuring the bulk rheological properties of microliter quantities of packed cell suspensions in a magneto-acoustic viscometer. From a fundamental viewpoint, membrane viscosity is a manifestation of the collective interaction of membrane molecules. Thus, studies of membrane viscosity give insight into membrane structure. From a practical viewpoint, viscous dissipation in the membrane surface influences its response to infectious disease, immunological reactions and hemolytic phenomena. In addition, the ability of red cell to respond to rapid shape changes as it moves through the circulation is influenced and controlled by the viscous nature of the membrane. All of these factors (membrane and cell viscosity, membrane diffusivity and cell deformability) will be studied.