CELL PARTITIONING WITH TWO PHASE AQUEOUS POLYMERS

聚合物水相体系中细胞和膜的分配 逆流分布（CCD）的手段已被经验证明， 是一种灵敏的、多功能的表征技术， 基于表面或膜的细胞亚群的分级 特性. 建议继续评价和制定一项 在这样的系统中细胞分配的热力学模型，因为 分区理论发展到今天预测更高的分辨率 分离比观察到的。 不同的相位系统将被检查 含有多种阴离子，特别是磷酸盐和硫酸盐。 的 系统将根据聚合物含量、盐 相的组成、密度和粘度、界面张力，以及 以及相的静电和表面电势。 的影响 聚合物的分子量和聚合物的化学组成将被检查 通过使用具有各种聚合物的PEG-葡聚糖和聚蔗糖-葡聚糖系统， 分子量 我们将研究划分的其他决定因素 包括测量单个电池上的三相接触角 吸附在相边界，细胞相液滴相互作用， 流体剪切和对流对确定分配影响。 以及 具有限定尺寸和表面性质的表征的模型颗粒， 因为单分散聚苯乙烯胶乳将用于评价一些 预测粒子相分配的主要决定因素。 的 将评估CCD方法的实验和系统变量， 新技术探索用于分离细胞群， 只有轻微的表面性质。 从基础知识中获得的知识 研究将用于检查红细胞的分配行为 多发性硬化症（MS）、遗传性球形红细胞增多症和 阵发性睡眠性血红蛋白尿（PNH）。 在MS的情况下， 开发一种诊断这种疾病的测试方法， 在MS上产生新的机制信息，并与PNH初步CCD 研究使我们能够非破坏性地分离出异常的红细胞 亚群

Partitioning of cells and membranes in tow-polymer aqueous phase systems by means of counter current distribution (CCD) has been shown empirically to be a sensitive, versatile technique for the characterization and fractionation of cell subpopulations on the basis of surface or membrane properties. It is propsed to continue evaluation and development of a thermodynamic model of cell partitioning in such systems, since the partition theory developed to date predicts much higher resolution separations than are observed. Different phase systems will be examined containing variety of anions, especially phosphate and sulfate. The systems will be characterized in terms of polymer content, salt composition, density and viscosity of the phases, interfacial tensions, and also electrostatic and surface potentials of the phases. The effects of poymer molecular weight and polymer chemical composition will be examined by using PEG-dextran and ficoll-dextran systems with polymers of various molecular weights. Other determinants of partitioning will be examined including measurement of three phase contact angles on single cells adsorbed at the phase boundary, cell-phase droplet interactions and influence of fluid shear and convection in determining partition. Well characterized model particles of defined sizes and surface properties such as monodisperse polystyrene latices will be used to evaluate some of the predicted primary determinants of particle phase partitioning. The experimental and system variables of the CCD method will be evaluated and new techniques explored for the separation of cell populations which differ only slightly in surface properties. The knowledge gained from the basic studies will be used to examine the partitioning behavior of erythrocytes from patients with multiple sclerosis (MS), hereditary spherocytosis and paroxysmal nocturnal hemoglobinuria (PNH). In the case of MS is is hoped to develop a test for the diagnosis of the disease which in addition could yield new mechanistic information on MS, and with PNH preliminary CCD studies have enabled us to nondestructively isolate abnormal RBC subpopulations.