Department of Bioengineering, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, People's Republic of China.
Nanotechnology. 2012 Dec 7;23(48):485102. doi: 10.1088/0957-4484/23/48/485102. Epub 2012 Nov 6.
Engaging functional biomaterial scaffolds to regulate stem cell differentiation has drawn a great deal of attention in the tissue engineering and regenerative medicine community. In this study, biomimetic composite nanofibrous scaffolds of hydroxyapatite/chitosan (HAp/CTS) were prepared to investigate their capacity for inducing murine mesenchymal stem cells (mMSCs) to differentiate into the osteogenic lineage, in the absence and presence of an osteogenic supplementation (i.e., ascorbic acid, β-glycerol phosphate, and dexamethasone), respectively. Using electrospun chitosan (CTS) nanofibrous scaffolds as the control, cell morphology, growth, specific osteogenic genes expression, and quantified proteins secretion on the HAp/CTS scaffolds were sequentially examined and assessed. It appeared that the HAp/CTS scaffolds supported better attachment and proliferation of the mMSCs. Most noteworthy was that in the absence of the osteogenic supplementation, expression of osteogenic genes including collagen I (Col I), runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP), and osteocalcin (OCN) were significantly upregulated in mMSCs cultured on the HAp/CTS nanofibrous scaffolds. Also increased secretion of the osteogenesis protein markers of alkaline phosphatase and collagen confirmed that the HAp/CTS nanofibrous scaffold markedly promoted the osteogenic commitment in the mMSCs. Moreover, the presence of osteogenic supplementation proved an enhanced efficacy of mMSC osteogenesis on the HAp/CTS nanofibrous scaffolds. Collectively, this study demonstrated that the biomimetic nanofibrous HAp/CTS scaffolds could support and enhance the adhesion, proliferation, and particularly osteogenic differentiation of the mMSCs. It also substantiated the potential of using biomimetic nanofibrous scaffolds of HAp/CTS for functional bone repair and regeneration applications.
仿生复合纳米纤维羟基磷灰石/壳聚糖（HAp/CTS）支架用于诱导间充质干细胞（mMSCs）向成骨谱系分化的研究
在组织工程和再生医学领域，通过功能生物材料支架来调节干细胞分化引起了广泛关注。本研究制备了仿生复合纳米纤维羟基磷灰石/壳聚糖（HAp/CTS）支架，分别在有无成骨补充剂（即抗坏血酸、β-甘油磷酸和地塞米松）的情况下，研究其诱导鼠间充质干细胞（mMSCs）向成骨谱系分化的能力。以电纺壳聚糖（CTS）纳米纤维支架作为对照，依次检测和评估了 HAp/CTS 支架上细胞形态、生长、特定成骨基因表达和定量蛋白分泌情况。结果表明，HAp/CTS 支架更有利于 mMSCs 的附着和增殖。最值得注意的是，在没有成骨补充剂的情况下，mMSCs 在 HAp/CTS 纳米纤维支架上培养时，骨形成基因包括Ⅰ型胶原（Col I）、成 Runt 相关转录因子 2（Runx2）、碱性磷酸酶（ALP）和骨钙素（OCN）的表达显著上调。碱性磷酸酶和成骨蛋白标志物胶原的分泌增加也证实了 HAp/CTS 纳米纤维支架显著促进了 mMSCs 的成骨分化。此外，成骨补充剂的存在证明了 HAp/CTS 纳米纤维支架对 mMSC 成骨的增强作用。总之，本研究表明仿生纳米纤维 HAp/CTS 支架能够支持和增强 mMSCs 的粘附、增殖，特别是成骨分化。它还证实了使用 HAp/CTS 仿生纳米纤维支架进行功能性骨修复和再生应用的潜力。
