Rapid Manufacturing Engineering Center, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai, China.
Shanghai Key Laboratory of Intelligent Manufacturing and Robotics, Shanghai University, Shanghai, China.
J Biomater Appl. 2020 Oct-Nov;35(4-5):553-566. doi: 10.1177/0885328220935090. Epub 2020 Jul 1.
Aligned electrospun fibers used for the fabrication of tubular scaffolds possess the ability to regulate cellular alignment and relevant functional expression, with applications in tissue engineering. Despite significant progress in the fabrication of small-diameter vascular grafts (SDVGs) over the past decade, several challenges remain; one of the most problematic of these is the fabrication of aligned nanofibers for multilayer SDVGs. Furthermore, delamination between each layer is difficult to avoid during the fabrication of multilayer structures. This study introduces a new fabrication method for minute delamination four-layer tubular scaffolds (FLTSs) that consist of an interior layer with highly longitudinal aligned nanofibers, two middle layers composed of electrospun sloped and circumferentially aligned fibers, and an exterior layer comprising random fibers. These FLTSs are used to simulate the structures and functions of native blood vessels. Here, thermoplastic polyurethane (TPU)/polycaprolactone (PCL)/polyethylene glycol (PEG) were electrospun to fabricate FLTSs or tubular scaffolds with completely random fibers layer (RLTSs). The surface wettability of the TPU/PCL/PEG tubular scaffold was tested by water contact angle analysis. In particular, compared with RLTSs, FLTSs showed excellent mechanical properties, with higher circumferential and longitudinal tensile properties. Furthermore, the high viability of the human umbilical vein endothelial cells (HUVECs) on the FLTSs indicated the biocompatibility of the tubular scaffolds comparing to RLTSs. The aligned and random composite structure of the FLTSs are conducive to promoting the growth of HUVECs, and the cell adhesion and proliferation on these scaffolds was found to be superior to that on RLTSs. These results demonstrate that the fabricated FLTSs have the potential for application in vascular tissue regeneration and clinical arterial replacements.
用于制造管状支架的对齐电纺纤维具有调节细胞对齐和相关功能表达的能力，可应用于组织工程。尽管在过去十年中，小直径血管移植物 (SDVG) 的制造取得了重大进展，但仍存在一些挑战；其中最成问题的一个挑战是制造用于多层 SDVG 的对齐纳米纤维。此外，在制造多层结构时，很难避免各层之间的分层。本研究介绍了一种新的制造方法，用于制造由内层具有高度纵向对齐纳米纤维、两层由电纺倾斜和周向对齐纤维组成以及外层由随机纤维组成的微小分层四层管状支架 (FLTS)。这些 FLTS 用于模拟天然血管的结构和功能。在这里，热塑性聚氨酯 (TPU)/聚己内酯 (PCL)/聚乙二醇 (PEG) 被电纺以制造具有完全随机纤维层 (RLTS) 的 FLTS 或管状支架。通过水接触角分析测试 TPU/PCL/PEG 管状支架的表面润湿性。特别是与 RLTS 相比，FLTS 表现出优异的机械性能，具有更高的周向和纵向拉伸性能。此外，FLTS 上的人脐静脉内皮细胞 (HUVEC) 具有较高的活力表明与 RLTS 相比，管状支架具有良好的生物相容性。FLTS 的对齐和随机复合结构有利于促进 HUVEC 的生长，并且发现细胞在这些支架上的粘附和增殖优于 RLTS。这些结果表明，所制造的 FLTS 具有应用于血管组织再生和临床动脉替代的潜力。
