Nagase Kenichi, Watanabe Minami, Kikuchi Akihiko, Okano Teruo
Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima, 734-8553, Japan.
Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, 8-1 Kawada-cho, Shinjuku, Tokyo, 162-8666, Japan.
Biomater Sci. 2025 Mar 25;13(7):1657-1670. doi: 10.1039/d4bm01705f.
Various cell sheets have been used as effective and useful cellular tissues in tissue engineering and regenerative therapy. Poly(-isopropylacrylamide) (PNIPAAm)-modified surfaces have been investigated for effective cell sheet preparation. In this study, the effective PNIPAAm graft density and chain length of PNIPAAm brushes for various cell types were investigated. The PNIPAAm brush-grafted glass was prepared silanization and subsequent atom transfer radical polymerization (ATRP). The density of the PNIPAAm brushes was modulated by changing the ATRP initiator and co-adsorber composition, while the PNIPAAm brush length was modulated by changing the monomer concentration in the ATRP. The hydrophilicity of the PNIPAAm brushes increased with increasing PNIPAAm brush length because long PNIPAAm brushes tended to hydrate. Fibronectin adsorption increased with decreasing PNIPAAm brush concentration because the exposed hydrophobic co-adsorber in the dilute PNIPAAm brush enhanced the adsorption of fibronectin. The cell-sheet fabrication ability was investigated using six types of PNIPAAm brushes. An endothelial cell sheet was fabricated using a dense, short PNIPAAm brush. NIH/3T3 sheets can be fabricated using three types of PNIPAAm brushes: dense-long PNIPAAm brushes, moderately dense-short PNIPAAm brushes, and dilute-long PNIPAAm brushes. MDCK cell sheets could not be prepared using the PNIPAAm brushes. A549 cell sheets were prepared using a dense-short PNIPAAm brush and moderately dense-short PNIPAAm brushes. These results indicate that the optimal PNIPAAm brush conditions for cell sheet preparation vary depending on cell type. Thus, modulation of PNIPAAm brush density and length is an effective approach for preparing target cell sheets.
在组织工程和再生治疗中，各种细胞片已被用作有效且有用的细胞组织。聚（N-异丙基丙烯酰胺）（PNIPAAm）修饰的表面已被研究用于有效的细胞片制备。在本研究中，研究了针对各种细胞类型的有效PNIPAAm接枝密度和PNIPAAm刷的链长。通过硅烷化和随后的原子转移自由基聚合（ATRP）制备了PNIPAAm刷接枝的玻璃。通过改变ATRP引发剂和共吸附剂的组成来调节PNIPAAm刷的密度，而通过改变ATRP中的单体浓度来调节PNIPAAm刷的长度。PNIPAAm刷的亲水性随着PNIPAAm刷长度的增加而增加，因为长的PNIPAAm刷易于水合。纤连蛋白的吸附随着PNIPAAm刷浓度的降低而增加，因为在稀PNIPAAm刷中暴露的疏水共吸附剂增强了纤连蛋白的吸附。使用六种类型的PNIPAAm刷研究了细胞片制造能力。使用致密、短的PNIPAAm刷制备了内皮细胞片。NIH/3T3片可以使用三种类型的PNIPAAm刷制备：致密长PNIPAAm刷、中等致密短PNIPAAm刷和稀长PNIPAAm刷。使用PNIPAAm刷无法制备MDCK细胞片。使用致密短PNIPAAm刷和中等致密短PNIPAAm刷制备了A549细胞片。这些结果表明，用于细胞片制备的最佳PNIPAAm刷条件因细胞类型而异。因此，调节PNIPAAm刷的密度和长度是制备目标细胞片的有效方法。
