Teramura Yuji, Asif Sana, Ekdahl Kristina N, Gustafson Elisabet, Nilsson Bo
Department of Bioengineering, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Department of Immunology, Genetics, and Pathology (IGP), Uppsala University , Dag Hammarskjölds väg 20, SE-751 85 Uppsala, Sweden.
ACS Appl Mater Interfaces. 2017 Jan 11;9(1):244-254. doi: 10.1021/acsami.6b14584. Epub 2016 Dec 23.
We synthesized a novel material, cell-penetrating peptide-conjugated poly(ethylene glycol)-lipid (CPP-PEG-lipid), that can induce the adhesion of floating cells. Firm cell adhesion with spreading could be induced by cell surface modification with the CPP-PEG-lipids. Cell adhesion was induced by CPPs but not by any other cationic short peptides we tested. Here, we demonstrated adherence using the floating cell line CCRF-CEM as well as primary human T cells, B cells, erythrocytes, and hepatocytes. As compared to cells grown in suspension, adherent cells were more rapidly induced to attach to substrates with the cell-surface modification. The critical factor for attachment was localization of CPPs at the cell membrane by PEG-lipids with PEG > 20 kDa. These cationic CPPs on PEG chains were able to interact with substrate surfaces such as polystyrene (PS) surfaces, glass surfaces, and PS microfibers that are negatively charged, inducing firm cell adhesion and cell spreading. Also, as opposed to normal cationic peptides that interact strongly with cell membranes, CPPs were less interactive with the cell surfaces because of their cell-penetrating property, making them more available for adhering cells to the substrate surface. No effects on cell viability or cell proliferation were observed after the induction of cell adhesion. With this technique, cells could be easily immobilized onto PS microfibers, an important step in fabricating 3D cell-based structures. Cells immobilized onto 3D PS microfibers were alive, and human hepatocytes showed normal production of urea and albumin on the microfibers. This method is novel in inducing firm cell adhesion via a one-step treatment.
我们合成了一种新型材料，即细胞穿透肽偶联聚乙二醇脂质（CPP-PEG-脂质），它能够诱导悬浮细胞的黏附。通过用CPP-PEG-脂质进行细胞表面修饰，可以诱导细胞牢固黏附并铺展。细胞黏附是由细胞穿透肽诱导的，而我们测试的其他任何阳离子短肽都不能诱导细胞黏附。在这里，我们使用悬浮细胞系CCRF-CEM以及原代人T细胞、B细胞、红细胞和肝细胞证明了黏附现象。与悬浮培养的细胞相比，经细胞表面修饰的贴壁细胞能更快地附着于底物。黏附的关键因素是聚乙二醇分子量大于20 kDa的PEG-脂质将细胞穿透肽定位在细胞膜上。这些PEG链上的阳离子细胞穿透肽能够与带负电荷的底物表面相互作用，如聚苯乙烯（PS）表面、玻璃表面和PS微纤维，从而诱导细胞牢固黏附和铺展。此外，与与细胞膜强烈相互作用的正常阳离子肽不同，细胞穿透肽由于其细胞穿透特性与细胞表面的相互作用较弱，这使得它们更有利于细胞附着于底物表面。诱导细胞黏附后，未观察到对细胞活力或细胞增殖的影响。通过这种技术，细胞可以很容易地固定在PS微纤维上，这是构建基于细胞的三维结构的重要一步。固定在三维PS微纤维上的细胞是活的，人肝细胞在微纤维上显示出正常的尿素和白蛋白生成。这种方法通过一步处理诱导细胞牢固黏附是新颖的。
