Scaffolds Formed via the Non-Equilibrium Supramolecular Assembly of the Synergistic ECM Peptides RGD and PHSRN Demonstrate Improved Cell Attachment in 3D
Scaffolds Formed via the Non-Equilibrium Supramolecular Assembly of the Synergistic ECM Peptides RGD and PHSRN Demonstrate Improved Cell Attachment in 3D
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DOI：
10.3390/polym10070690
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发表时间：
2018-07-01
期刊：
影响因子：
5
通讯作者：
Williams, Richard J.
中科院分区：
文献类型：
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作者：
Aye, San-Seint S.;Li, Rui;Williams, Richard J.
自组装肽（SAPs）是一类相对较新的低分子量凝胶，它通过自发形成（纤维状）纳米结构来固定溶剂。由于多肽来源于蛋白质，这些水凝胶非常适合用作再生医学的生物相容性支架。重要的是，由于肽序列在自然界中充当信号的倾向，它们很容易通过包含生物活性表位而功能化为细胞指导。在自然界中，纤维连接蛋白肽序列精氨酸-甘氨酸-天冬氨酸（RGD）协同促进整合素α (5) β(1)介导的细胞与另一个表位脯氨酸-组氨酸-丝氨酸-精氨酸-天冬氨酸（PHSRN）的粘附；然而，大多数功能化策略只关注RGD。在这里，我们首次讨论了这两个序列在一个自组装的极简肽水凝胶中的仿生包涵。在这里，基于我们对Fmoc-FRGDF （n -氟酰甲基氧羰基苯丙氨酸-精氨酸-甘氨酸-天冬氨酸-苯丙氨酸）的研究，我们发现通过两个sap的共组装来组装两个表位是可能同时呈现两个表位的，并将其与单个肽信号的有效性进行比较；Fmoc-FRGDF: Fmoc-PHSRN （n -氟酰甲基氧羰基-脯氨酸-组氨酸-丝氨酸-精氨酸-天冬酰胺）和Fmoc-FRGDFPHSRN （n -氟酰甲基氧羰基-苯丙氨酸-精氨酸-甘氨酸-天冬氨酸-苯丙氨酸-脯氨酸-组氨酸-丝氨酸-精氨酸-天冬酰胺）。我们发现，这两种方法都可以产生由纠缠的纳米原纤维支撑的自支撑水凝胶，然而，共组装水凝胶的刚度比单独的Fmoc-FRGDF或Fmoc-FRGDFPHSRN高出两个数量级以上。水凝胶混合肽对人乳腺成纤维细胞进行体外三维细胞培养，结果显示Fmoc-FRGDF对人乳腺成纤维细胞的粘附、扩散和增殖有显著改善。然而，长肽不能提供有效的细胞附着。结果表明，PHSRN与RGD的选择性协同效应是增强自组装生物支架鲁棒性和功能性的有效途径。
Self-assembling peptides (SAPs) are a relatively new class of low molecular weight gelators which immobilize their solvent through the spontaneous formation of (fibrillar) nanoarchitectures. As peptides are derived from proteins, these hydrogels are ideal for use as biocompatible scaffolds for regenerative medicine. Importantly, due to the propensity of peptide sequences to act as signals in nature, they are easily functionalized to be cell instructive via the inclusion of bioactive epitopes. In nature, the fibronectin peptide sequence, arginine-glycine-aspartic acid (RGD) synergistically promotes the integrin alpha(5)beta(1) mediated cell adhesion with another epitope, proline-histidine-serine-arginine-asparagine (PHSRN); however most functionalization strategies focus on RGD alone. Here, for the first time, we discuss the biomimetic inclusion of both these sequences within a self-assembled minimalistic peptide hydrogel. Here, based on our work with Fmoc-FRGDF (N-flourenylmethyloxycarbonyl phenylalanine-arginine-glycine-aspartic acid-phenylalanine), we show it is possible to present two epitopes simultaneously via the assembly of the epitopes by the coassembly of two SAPs, and compare this to the effectiveness of the signals in a single peptide; Fmoc-FRGDF: Fmoc-PHSRN (N-flourenylmethyloxycarbonyl-proline-histidine-serine-arginine-asparagine) and Fmoc-FRGDFPHSRN (N-flourenylmethyloxycarbonyl-phenylalanine-arginine-glycine-asparticacidphenylalanine-proline-histidine-serine-arginine-asparagine). We show both produced self-supporting hydrogel underpinned by entangled nanofibrils, however, the stiffness of coassembled hydrogel was over two orders of magnitude higher than either Fmoc-FRGDF or Fmoc-FRGDFPHSRN alone. In-vitro three-dimensional cell culture of human mammary fibroblasts on the hydrogel mixed peptide showed dramatically improved adhesion, spreading and proliferation over Fmoc-FRGDF. However, the long peptide did not provide effective cell attachment. The results demonstrated the selective synergy effect of PHSRN with RGD is an effective way to augment the robustness and functionality of self-assembled bioscaffolds.