Selective Adhesive Cell Capture without Molecular Specificity: New Surfaces Exploiting Nanoscopic Polycationic Features as Discrete Adhesive Units.
Selective Adhesive Cell Capture without Molecular Specificity: New Surfaces Exploiting Nanoscopic Polycationic Features as Discrete Adhesive Units.
复制标题
无分子特异性的选择性粘附细胞捕获：利用纳米聚阳离子特征作为离散粘附单元的新表面。
DOI：
10.1039/c7ra01217a
复制
发表时间：
2017
期刊：
影响因子：
3.9
通讯作者：
Santore,MM
中科院分区：
文献类型：
--
作者：
Kalasin,S;Browne,EP;Arcaro,KF;Santore,MM
这项工作探讨了收集表面上的分子非特异性聚阳离子纳米级特征如何控制哺乳动物细胞捕获的动力学和选择性方面。通过比较两种密切相关的乳腺癌细胞系：MCF-7 和 TMX2-28 的捕获，证明了选择性收集器设计的关键原则。 TMX2-28 是 MCF-7 的他莫昔芬选择克隆。收集器是二氧化硅表面，在 pH 7.4 时带负电荷，包含阳离子聚合物聚（甲基丙烯酸二甲氨基乙酯）pDMAEMA 的分离分子（直径约 8 nm）。这项工作中重要的是 pDMAEMA 与细胞相互作用的非选择性性质：pDMAEMA 通常粘附溶液中带负电的颗粒和细胞。我们在此表明，对细胞的选择性源于收集器设计：这包括涉及负二氧化硅的排斥相互作用与固定 pDMAEMA 分子的吸引力、表面上的随机 pDMAEMA 排列以及吸附的 pDMAEMA 链附近的正电荷浓度之间的竞争。后者充当纳米级阳离子表面斑块，每个斑块都微弱地吸引带负电的细胞。收集用适量 pDMAEMA 工程化的表面，暴露于 MCF-7 和 TMX2-28 细胞的混合物，优先捕获 TMX2-28，选择性为 2.5。 （这意味着表面上 TMX2-28 与 MCF 细胞的比例是其在自由溶液中组成比例的 2.5 倍。）细胞捕获的离子强度依赖性与相同表面上的二氧化硅微粒的离子强度依赖性相似。这表明选择性细胞捕获的机制涉及细胞与收集器接触面积的纳米级差异，从而能够区分细胞表面密切相关的基于细胞系的小尺度特征。这项工作证明，即使没有分子特异性，对物理细胞属性的选择性也会产生粘附歧视。
This work explored how molecularly non-specific polycationic nanoscale features on a collecting surface control kinetic and selectivity aspects of mammalian cell capture. Key principles for selective collector design were demonstrated by comparing the capture of two closely related breast cancer cell lines: MCF-7 and TMX2-28. TMX2-28 is a tamoxifen-selected clone of MCF-7. The collector was a silica surface, negatively-charged at pH 7.4, containing isolated molecules (∼8 nm diameter) of the cationic polymer, poly(dimethyl-aminoethylmethacrylate), pDMAEMA. Important in this work is the non-selective nature of the pDMAEMA interactions with cells: pDMAEMA generally adheres negatively charged particles and cells in solution. We show here that selectivity towards cells results from collector design: this includes competition between repulsive interactions involving the negative silica and attractions to the immobilized pDMAEMA molecules, the random pDMAEMA arrangement on the surface, and the concentration of positive charge in the vicinity of the adsorbed pDMAEMA chains. The latter act as nanoscopic cationic surface patches, each weakly attracted to negatively-charged cells. Collecting surfaces engineered with an appropriate amount pDMAEMA, exposed to mixtures of MCF-7 and TMX2-28 cells preferentially captured TMX2-28 with a selectivity of 2.5. (This means that the ratio of TMX2-28 to MCF cells on the surface was 2.5 times their compositional ratio in free solution.) The ionic strength-dependence of cell capture was shown to be similar to that of silica microparticles on the same surfaces. This suggests that the mechanism of selective cell capture involves nanoscopic differences in the contact areas of the cells with the collector, allowing discrimination of closely related cell line-based small scale features of the cell surface. This work demonstrated that even without molecular specificity, selectivity for physical cell attributes produces adhesive discrimination.