Wake Forest Institute for Regenerative Medicine, Winston-Salem, NC, USA.
Biomaterials. 2011 Feb;32(6):1549-59. doi: 10.1016/j.biomaterials.2010.10.038. Epub 2010 Nov 18.
Tissue engineering has had successes developing single tissue types, but there is a need for methods that will allow development of composite tissues. For instance, muscle-tendon junctions (MTJ) require a seamless interface to allow force transfer from muscle to tendon. One challenge in engineering MTJs is designing a continuous scaffold suitable for both tissue types. We aimed to create a dual scaffold that exhibits regional mechanical property differences that mimic the trends seen in native MTJ. Poly(ε-caprolactone)/collagen and poly(l-lactide)/collagen were co-electrospun onto opposite ends of a mandrel to create a scaffold with 3 regions. Scaffolds were characterized with scanning electron microscopy, tensile testing (uniaxial, cyclic, and video strain), for cytocompatibility using MTS, and seeded with C2C12 myoblasts and NIH3T3 fibroblasts. Native porcine diaphragm MTJs were also analyzed with video strain for comparison. Integrated scaffolds were created with fiber diameters from 452-549 nm. Scaffolds exhibited regional variations in mechanical properties with moduli from 4.490-27.62 MPa and generally withstood cyclic testing, although with hysteresis. Video analysis showed scaffold strain profiles exhibited similar trends to native MTJ. The scaffolds were cytocompatible and accommodated cell attachment and myotube formation. The properties engineered into these scaffolds make them attractive candidates for tissue engineering of MTJs.
组织工程在开发单一组织类型方面取得了成功，但需要开发能够构建复合组织的方法。例如，肌肉-肌腱连接（MTJ）需要一个无缝的界面，以允许力从肌肉传递到肌腱。在工程 MTJ 中，一个挑战是设计适合两种组织类型的连续支架。我们旨在创建一种双支架，其具有模仿天然 MTJ 中所见趋势的区域机械性能差异。聚（ε-己内酯）/胶原蛋白和聚（L-丙交酯）/胶原蛋白被共静电纺丝到芯轴的相对两端，以创建具有 3 个区域的支架。使用扫描电子显微镜、单轴、循环和视频应变测试对支架进行了表征，使用 MTS 进行细胞相容性测试，并接种 C2C12 成肌细胞和 NIH3T3 成纤维细胞。还使用视频应变分析了天然猪膈肌 MTJ 以进行比较。集成支架的纤维直径为 452-549nm。支架表现出机械性能的区域变化，模量为 4.490-27.62MPa，通常可以承受循环测试，尽管存在滞后。视频分析表明，支架应变曲线表现出与天然 MTJ 相似的趋势。这些支架具有细胞相容性，并适应细胞附着和肌管形成。这些支架中设计的特性使其成为 MTJ 组织工程的有吸引力的候选者。
