Engineering Research Center of Technical Textiles of Ministry of Education, College of Textiles, Donghua University, Shanghai 201620, People's Republic of China. Key Laboratory of Textile Industry for Biomedical Textile materials and Technology, College of Textiles, Donghua University, Shanghai 201620, People's Republic of China. Key Laboratory of Textile Science and Technology of Ministry of Education, College of Textiles, Donghua University, Shanghai 201620, People's Republic of China.
Biomed Mater. 2020 Mar 4;15(3):035005. doi: 10.1088/1748-605X/ab673c.
An endothelial cell (EC) monolayer aligned along the direction of blood flow in vivo shows excellent capacity for anti-inflammation and anti-thrombosis. Therefore, aligned electrospun fibers have been much studied in the field of vascular implants since they are considered to facilitate the formation of an aligned EC monolayer, yet few research studies have been comprehensively reported concerning the effects of diameter scales of aligned fibers. In the present work, a series of aligned polycaprolactone (PCL) electrospun fibers with varying diameters ranging from dozens of nanometers to several micrometers were developed, and the effects of the fiber scales on EC behaviors, hemocompatibility as well as inflammatory cell behaviors were investigated, to evaluate their potential performance in the field of vascular implants. Our results showed that platelets exhibited small attachment forces on all fibers, and the anticoagulation property improved with the decrease of the fiber diameters. The impact of fiber diameters on human umbilical vein endothelial cell (HUVEC) adhesion and NO release was limited, while significant on HUVEC proliferation. With the increase of the fiber diameters, the elongation of HUVECs on our samples increased first then decreased, and exhibited maximum elongation degrees on 2738 nm and 2036 nm due to the strong contact guidance effect on these graphical cues; too thick or too fine fibers would weaken the contact guidance effect. Furthermore, we hypothesized that HUVECs cultured on 2036 nm had the smallest spreading area because of their elongation, but 2738 nm restricted HUVECs spreading limitedly. Similarly, NO production of HUVECs showed a similar change trend as their elongation degrees on different fibers. Except for 2036 nm, it exhibited the second highest NO production. For RAW 264.7 cells, poorer cell adhesion and lower TNF-α concentration of 1456 nm indicated its superior anti-inflammation property, while 73 nm showed a contrasting performance. Overall, these findings partly revealed the relationship between different topographies and cell behaviors, providing basic insight into vascular implant design.
体内沿血流方向排列的内皮细胞（EC）单层具有出色的抗炎和抗血栓形成能力。因此，在血管植入物领域，人们对排列整齐的静电纺纤维进行了大量研究，因为它们被认为有利于形成排列整齐的 EC 单层，但关于排列纤维的直径对细胞行为影响的研究很少有全面报道。在本工作中，我们制备了一系列具有不同直径（从几十纳米到几微米）的排列聚己内酯（PCL）静电纺纤维，研究了纤维尺寸对 EC 行为、血液相容性和炎症细胞行为的影响，以评估它们在血管植入物领域的潜在性能。我们的结果表明，血小板在内的所有纤维上的附着力都较小，随着纤维直径的减小，抗凝性能提高。纤维直径对人脐静脉内皮细胞（HUVEC）黏附和 NO 释放的影响有限，但对 HUVEC 增殖的影响显著。随着纤维直径的增加，细胞在样品上的伸长先增加后减小，在 2738nm 和 2036nm 时达到最大伸长度，因为这些图形线索具有很强的接触导向作用；太粗或太细的纤维会削弱接触导向作用。此外，我们假设培养在 2036nm 纤维上的 HUVEC 由于其伸长而具有最小的铺展面积，但 2738nm 纤维限制了 HUVEC 的铺展。同样，HUVEC 上不同纤维的 NO 产生也表现出与伸长度相似的变化趋势。除 2036nm 外，其 NO 产量排名第二。对于 RAW264.7 细胞，1456nm 的较差细胞黏附和较低的 TNF-α浓度表明其具有较好的抗炎性能，而 73nm 则表现出相反的性能。总的来说，这些发现部分揭示了不同形貌与细胞行为之间的关系，为血管植入物设计提供了基础见解。
