Department of Medicine, Center for Biomedical Engineering, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts 02139, USA.
Tissue Eng Part A. 2011 Jul;17(13-14):1713-23. doi: 10.1089/ten.TEA.2010.0666. Epub 2011 Apr 12.
Poly(ethylene glycol) (PEG) hydrogels are popular for cell culture and tissue-engineering applications because they are nontoxic and exhibit favorable hydration and nutrient transport properties. However, cells cannot adhere to, remodel, proliferate within, or degrade PEG hydrogels. Methacrylated gelatin (GelMA), derived from denatured collagen, yields an enzymatically degradable, photocrosslinkable hydrogel that cells can degrade, adhere to and spread within. To combine the desirable features of each of these materials we synthesized PEG-GelMA composite hydrogels, hypothesizing that copolymerization would enable adjustable cell binding, mechanical, and degradation properties. The addition of GelMA to PEG resulted in a composite hydrogel that exhibited tunable mechanical and biological profiles. Adding GelMA (5%-15% w/v) to PEG (5% and 10% w/v) proportionally increased fibroblast surface binding and spreading as compared to PEG hydrogels (p<0.05). Encapsulated fibroblasts were also able to form 3D cellular networks 7 days after photoencapsulation only within composite hydrogels as compared to PEG alone. Additionally, PEG-GelMA hydrogels displayed tunable enzymatic degradation and stiffness profiles. PEG-GelMA composite hydrogels show great promise as tunable, cell-responsive hydrogels for 3D cell culture and regenerative medicine applications.
聚乙二醇（PEG）水凝胶因其无毒性且具有良好的水合和营养传输性能，而常用于细胞培养和组织工程应用。然而，细胞无法在 PEG 水凝胶中黏附、重塑、增殖或降解。明胶甲基丙烯酰（GelMA）来源于变性胶原，生成一种可酶降解、光交联的水凝胶，细胞可在其中降解、黏附和扩展。为了结合这两种材料的优点，我们合成了 PEG-GelMA 复合水凝胶，假设共聚作用将使细胞结合、机械和降解性能具有可调性。GelMA 的添加使 PEG 产生了具有可调机械和生物学特性的复合水凝胶。与 PEG 水凝胶相比（p<0.05），添加 GelMA（5%-15%w/v）到 PEG（5%和 10%w/v）中会相应增加成纤维细胞表面的黏附和扩展。与单独使用 PEG 相比，在光包封后 7 天，仅在复合水凝胶中包封的成纤维细胞也能够形成 3D 细胞网络。此外，PEG-GelMA 水凝胶具有可调节的酶降解和硬度特性。PEG-GelMA 复合水凝胶有望成为可调节的、细胞响应性的 3D 细胞培养和再生医学应用的水凝胶。
