Development of contimous cell separation system using polymeric adsorbent with surface micro-structures

本文用一个带有聚合物涂层底壁的平面平行型通道，研究了大鼠淋巴细胞亚群与聚（甲基丙烯酸2-羟乙酯）-接枝-多胺共聚物（HA）和聚（甲基丙烯酸2-羟乙酯）-接枝-部分季铵化多胺共聚物（HQA）表面在可控剪切应力下的相互作用。将引入通道中的细胞沉降规定的时间段，然后暴露于由通道中的抛物线流产生的剪切应力。当剪切应力超过细胞/表面相互作用的强度时，细胞能够从聚合物表面脱离。通过这种方式，细胞/表面相互作用的定量评价是在时间依赖性的方式来澄清的效果的接枝共聚物中的多胺部分的季铵化对淋巴细胞附着。延长的沉降时间（Tsf）导致淋巴细胞与HA通道的共聚物表面之间的附着力逐渐增加，导致B和T细胞从通道的回收率显著降低。相反，从HQA通道回收的T细胞仅显示出随着沉降时间的轻微降低，即使在具有延长的沉降时间的条件下也允许以良好的产率获得作为流出物的T细胞群。观察到HA通道的细胞/表面相互作用的时间依赖性增加可能是由于HA共聚物的疏水性增加引起的疏水相互作用的渐进贡献，通过在细胞界面的多胺接枝物中的乙二胺单元的去质子化。这些结果表明，淋巴细胞的附着是能够通过改变多胺接枝共聚物中的电荷的量和性质（固定或不固定）来控制。

The interaction of rat lymphocyte subpopulations with the surfaces of poly (2-hydroxyethyl methacrylate) -graft-polyamine copolymer (HA) and poly (2-hydroxyethyl methacrylate) -graft-partially quaternized polyamine copolymer (HQA) was evaluated under a controlled shear stress by using a plane-parallel type channel equipped with a polymer-coated bottom wall. The cells introduced into the channel were settled for a prescribed time period, followed by the exposure to a shear stress resulting from the parabolic flow in the channel. When the shear stress exceeded the strength of cell/surface interaction, the cells were able to be detached from the polymer surface. By this way, quantitative evaluation of cell/surface interaction was done in time-dependent manner to clarify the effect of quaternization of polyamine portion in graft copolymer on lymphocyte attachment. Extended settling time (Tsf) caused a progressive increase in the attachment force between lymphocyte and copolymer surface for HA channel, resulting in a considerable decrease in the recovery of both B and T cells from the channel. On the contrary, recovery of T cells from HQA channel showed only a slight decrease with a settling time, allowing to obtain T cell population as effluent in a good yield even under the condition with prolonged settling time. Time-dependent increase in cell/surface interaction observed for HA channel might be due to a progressive contribution of hydrophobic interaction caused by an increase in hydrophobicity of HA copolymer through the deprotonation of ethylenediamine units in polyamine grafts at cellular interface. These results indicated that lymphocyte attachment is able to be controlled by changing the amount and the nature (fixed our unfixed) of charge in polyamine graft copolymers.