Abstract

Dynamic control of mesenchymal stem cell (MSC) behaviors on biomaterial surface is critically involved in regulating the cell fate and tissue regeneration. Herein, a stimuli-responsive surface based on host-guest interaction with cell selectivity was developed to regulate migration of MSCs in situ by dynamic display of cell-specific peptides. Azobenzene-grafted MSC-affinitive peptides (EPLQLKM, Azo-E7) were grafted to β-cyclodextran (β-CD)-modified poly(2-hydroxyethyl methacrylate)-b-poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) (PHG) brushes, which were prepared by using surface-initiated atom transfer radical polymerization (SI-ATRP). X-ray photoelectron spectroscopy (XPS), quartz crystal microbalance (QCM), and water contact angle were used to characterize their structure and property. Cell adhesion assay showed that the combination effect of resisting property of PHG and MSC-affinity of E7 could promote the selective adhesion of MSCs over other types of cells such as RAW264.7 macrophages and NIH3T3 fibroblasts to some extent. UV-Vis spectroscopy proved that the competing guest molecules, amantadine hydrochloride (Ama), could release Azo-E7 peptides from the CD surface to different extents, and the effect was enhanced when UV irradiation was employed simultaneously. As a result, the decrease of cell adhesion density and migration rate could be achieved in situ. The cell density and migration rate could be reduced by over 40% by adding 20 μmol/L Ama, suggesting that this type of surface is a new platform for dynamic regulation of stem cell behaviors in situ.

中文翻译：

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通过动态改变固定在β-环糊精修饰的抗细胞聚合物刷上的细胞选择性肽的密度介导间充质干细胞的迁移

摘要

动态控制生物材料表面间充质干细胞（MSC）的行为与调节细胞命运和组织再生至关重要。本文中，开发了基于宿主-客体相互作用与细胞选择性的刺激响应表面，以通过动态展示细胞特异性肽原位调节MSC的迁移。偶氮苯接枝MSC体亲和性的肽（EPLQLKM，偶氮-E7的）被移植到β -cyclodextran（β -CD）改性聚（2-羟乙基甲基丙烯酸酯） - b -聚（2-羟乙基甲基丙烯酸酯共-甲基丙烯酸缩水甘油酯）（PHG）刷，是通过使用表面引发的原子转移自由基聚合（SI-ATRP）制备的。使用X射线光电子能谱（XPS），石英晶体微量天平（QCM）和水接触角来表征其结构和性质。细胞粘附试验表明，PHG的抗性和E7的MSC亲和力的联合作用在一定程度上可以促进MSC对其他类型细胞的选择性粘附，例如RAW264.7巨噬细胞和NIH3T3成纤维细胞。UV-Vis光谱证明竞争的客体分子盐酸金刚烷胺（Ama）可以从CD表面释放不同程度的Azo-E7肽，并且同时使用UV辐射可以增强效果。结果是，原位。加入20μmol/ L Ama可将细胞密度和迁移率降低40％以上，这表明这种类型的表面是原位动态调节干细胞行为的新平台。