Fabrication and characterisation of biomimetic, electrospun gelatin fibre scaffolds for tunica media-equivalent, tissue engineered vascular grafts
Fabrication and characterisation of biomimetic, electrospun gelatin fibre scaffolds for tunica media-equivalent, tissue engineered vascular grafts
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DOI：
10.1016/j.msec.2015.12.081
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发表时间：
2016-04-01
影响因子：
7.9
通讯作者：
Tomlins, P.
中科院分区：
文献类型：
--
作者：
Elsayed, Y.;Lekakou, C.;Tomlins, P.
人们越来越认识到，模仿细胞外基质（ECM）的仿生天然聚合物具有低血栓形成性和调节细胞-基质相互作用的功能基元，这些因素对于组织工程血管移植物，特别是小直径移植物至关重要。明胶是可溶性胶原蛋白的低成本替代品，但迄今为止，明胶支架的强度和缝合保持强度普遍较低。在这项研究中，我们设计了一种新型的电纺丝多层明胶纤维支架，控制纤维层方向，优化明胶交联，不仅达到了与冠状动脉相当的顺应性，而且首次实现了湿管状脱细胞支架（因吸水而肿胀）在周向和轴向上与冠状动脉中膜相同的强度。最重要的是，对于天然支架，特别是明胶，首次在1.8-1.94 N范围内实现了高缝线保持强度，与新鲜隐静脉相同或更好。该研究提出了将静电纺丝工艺参数与支架的微观结构参数联系起来的研究，这些微观结构参数进一步与湿式、交联式、静电纺丝支架在周向和轴向管状方向上的力学性能数据相关。该支架在人平滑肌细胞（SMC）增殖方面表现出优异的性能，在初始干孔隙率为74%和83%的支架中，SMC5在播种后9天沿局部纤维粘附、拉长和排列，沿支架厚度迁移，横向填充距离分别为186 pm和240 pm。(C) 2016 Elsevier B.V.版权所有
It is increasingly recognised that biomimetic, natural polymers mimicking the extracellular matrix (ECM) have low thrombogenicity and functional motifs that regulate cell-matrix interactions, with these factors being critical for tissue engineered vascular grafts especially grafts of small diameter. Gelatin constitutes a low cost substitute of soluble collagen but gelatin scaffolds so far have shown generally low strength and suture retention strength. In this study, we have devised the fabrication of novel, electrospun, multilayer, gelatin fibre scaffolds, with controlled fibre layer orientation, and optimised gelatin crosslinldng to achieve not only compliance equivalent to that of coronary artery but also for the first time strength of the wet tubular acellular scaffold (swollen with absorbed water) same as that of the tunica media of coronary artery in both circumferential and axial directions. Most importantly, for the first time for natural scaffolds and in particular gelatin, high suture retention strength was achieved in the range of 1.8-1.94 N for wet acellular scaffolds, same or better than that for fresh saphenous vein. The study presents the investigations to relate the electrospinning process parameters to the microstructural parameters of the scaffold, which are further related to the mechanical performance data of wet, crosslinked, electrospun scaffolds in both circumferential and axial tubular directions. The scaffolds exhibited excellent performance in human smooth muscle cell (SMC) proliferation, with SMC5 seeded on the top surface adhering, elongating and aligning along the local fibres, migrating through the scaffold thickness and populating a transverse distance of 186 pm and 240 pm 9 days post-seeding for scaffolds of initial dry porosity of 74 and 83%, respectively. (C) 2016 Elsevier B.V. All rights reserved.