Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China.
Division of Advanced Prosthodontics, University of California Los Angeles, 10833 Le Conte Avenue, Los Angeles, CA, 90095, USA.
Nat Commun. 2019 Aug 6;10(1):3523. doi: 10.1038/s41467-019-11511-3.
Injectable hydrogels can fill irregular defects and promote in situ tissue regrowth and regeneration. The ability of directing stem cell differentiation in a three-dimensional microenvironment for bone regeneration remains a challenge. In this study, we successfully nanoengineer an interconnected microporous networked photocrosslinkable chitosan in situ-forming hydrogel by introducing two-dimensional nanoclay particles with intercalation chemistry. The presence of the nanosilicates increases the Young's modulus and stalls the degradation rate of the resulting hydrogels. We demonstrate that the reinforced hydrogels promote the proliferation as well as the attachment and induced the differentiation of encapsulated mesenchymal stem cells in vitro. Furthermore, we explore the effects of nanoengineered hydrogels in vivo with the critical-sized mouse calvarial defect model. Our results confirm that chitosan-montmorillonite hydrogels are able to recruit native cells and promote calvarial healing without delivery of additional therapeutic agents or stem cells, indicating their tissue engineering potential.
可注射水凝胶可填充不规则缺陷，并促进原位组织再生和再生。在三维微环境中指导干细胞分化以促进骨再生的能力仍然是一个挑战。在这项研究中，我们通过引入具有插层化学的二维纳米粘土颗粒，成功地纳米工程化了一种相互连接的微孔网络光交联壳聚糖原位形成水凝胶。纳米硅酸盐的存在增加了杨氏模量并延缓了所得水凝胶的降解速率。我们证明，增强的水凝胶可促进体外包裹间充质干细胞的增殖、附着和诱导分化。此外，我们使用临界大小的小鼠颅骨缺损模型研究了纳米工程水凝胶的体内作用。我们的结果证实壳聚糖-蒙脱石水凝胶能够募集天然细胞并促进颅骨愈合，而无需输送其他治疗剂或干细胞，这表明它们具有组织工程潜力。
