Zhao Song, Zhao Xin, Dong Shikui, Yu Jia, Pan Guoqing, Zhang Yang, Zhao Jinzhong, Cui Wenguo
Orthopedic Institute, Soochow University, 708 Renmin Rd, Suzhou, Jiangsu 215006, P.R. China.
J Mater Chem B. 2015 Feb 14;3(6):990-1000. doi: 10.1039/c4tb01642d. Epub 2014 Dec 16.
The regeneration of fibrocartilage at the tendon-bone insertion site in rotator cuff tears (RCTs) is challenging due to the complexity of its composition and mechanical properties. In this study, hierarchical, stretchable and stiff fibrous scaffolds composed of microfibers of poly(ε-caprolactone) (PCL) and nanofibers of chitosan (CS) were fabricated using stagger-electrospinning for the augmentation of RCT-healing. It was found that the composite PCL-CS scaffolds had significantly improved strength and failure strain compared to the control CS scaffolds and increased stiffness compared to the control PCL scaffolds. These scaffolds also showed enhanced hydrophilicity, water absorption and a faster degradation rate compared to the PCL scaffolds. Moreover, they demonstrated better fibroblast attachment and proliferation compared to the PCL scaffolds. Radiological and histological analysis revealed that the PCL-CS scaffolds enhanced new bone formation (mineralization) and collagen and glycosaminoglycan expression (major components of extracellular matrix) compared to the PCL scaffolds. Furthermore, the torn tissues at the tendon-bone insertion site regenerated with the PCL-CS scaffolds showed higher strength and failure strain as well as stiffness compared to those repaired using only the PCL scaffolds. The above mentioned results suggest that the hierarchical, stretchable and stiff fibrous scaffolds engineered using stagger-electrospinning have great potential for the augmentation of RCT-healing.
由于肩袖撕裂（RCT）肌腱-骨附着部位纤维软骨的组成和力学性能复杂，其再生具有挑战性。在本研究中，采用交错静电纺丝法制备了由聚（ε-己内酯）（PCL）微纤维和壳聚糖（CS）纳米纤维组成的分层、可拉伸且坚硬的纤维支架，用于促进RCT愈合。结果发现，与对照CS支架相比，复合PCL-CS支架的强度和断裂应变显著提高，与对照PCL支架相比，刚度增加。与PCL支架相比，这些支架还表现出增强的亲水性、吸水性和更快的降解速率。此外，与PCL支架相比，它们表现出更好的成纤维细胞附着和增殖。放射学和组织学分析表明，与PCL支架相比，PCL-CS支架增强了新骨形成（矿化）以及胶原蛋白和糖胺聚糖表达（细胞外基质的主要成分）。此外，与仅使用PCL支架修复的组织相比，用PCL-CS支架再生的肌腱-骨附着部位的撕裂组织表现出更高的强度、断裂应变和刚度。上述结果表明，采用交错静电纺丝技术设计的分层、可拉伸且坚硬的纤维支架在促进RCT愈合方面具有巨大潜力。
