Lin Yung-Hao, Huang Kai-Wen, Chen Shao-Yung, Cheng Nai-Chen, Yu Jiashing
Department of Chemical Engineering, College of Engineering, National Taiwan University, Taipei 10617, Taiwan.
J Mater Chem B. 2017 Jun 28;5(24):4614-4622. doi: 10.1039/c7tb00188f. Epub 2017 May 22.
Keratin has intrinsic biocompatibility and contains several peptide-binding motifs that support the attachment of a wide variety of cell types. We have previously shown that keratin extracted from human hair can promote cell adhesion and proliferation of 3T3 fibroblasts, MG63 osteoblasts, and human adipose stem cells (hASCs). Despite its bioactivity advantages, keratin possesses fragile mechanical properties that introduce challenges for tissue engineering. To remedy this, we examined the results of combining keratin with chitosan, a combination facilitated via induction of an azide functional group, which acted as a photocrosslinker, to improve mechanical strength. Analysis of the keratin/chitosan composite showed that films of this material demonstrated good adhesion and promoted the proliferation of human adipose stem cells. Most importantly, this biomaterial was shown to promote the osteogenic differentiation of hASCs, in terms of up-regulations in type I collagen, runt-related transcription factor 2, and alkaline phosphatase gene expression. We further demonstrated that lyophilizing the keratin/chitosan forms highly interconnected and porous scaffolds that might provide an ideal environment for tissue culture. We believe that keratin/chitosan composite biomaterials can be used in bioactive surface modification, and the crosslinkable properties can produce natural polymer 3D scaffolds for the application of tissue engineering research.
角蛋白具有内在的生物相容性，并包含多个肽结合基序，可支持多种细胞类型的附着。我们之前已经表明，从人发中提取的角蛋白可以促进3T3成纤维细胞、MG63成骨细胞和人脂肪干细胞（hASC）的细胞黏附和增殖。尽管角蛋白具有生物活性优势，但其机械性能脆弱，给组织工程带来了挑战。为了解决这个问题，我们研究了将角蛋白与壳聚糖结合的结果，通过引入叠氮官能团促进二者结合，该官能团作为光交联剂来提高机械强度。对角蛋白/壳聚糖复合材料的分析表明，这种材料的薄膜表现出良好的黏附性，并促进了人脂肪干细胞的增殖。最重要的是，就I型胶原蛋白、 runt相关转录因子2和碱性磷酸酶基因表达的上调而言，这种生物材料被证明能促进hASC的成骨分化。我们进一步证明，冻干角蛋白/壳聚糖可形成高度互连的多孔支架，这可能为组织培养提供理想的环境。我们相信，角蛋白/壳聚糖复合生物材料可用于生物活性表面改性，其可交联特性能够生产用于组织工程研究的天然聚合物3D支架。
