Cattaneo Irene, Figliuzzi Marina, Azzollini Nadia, Catto Valentina, Farè Silvia, Tanzi Maria Cristina, Alessandrino Antonio, Freddi Giuliano, Remuzzi Andrea
Department of Biomedical Engineering and Department of Molecular Medicine, Mario Negri Institute, Bergamo, Italy.
Int J Artif Organs. 2013 Mar;36(3):166-74. doi: 10.5301/IJAO.5000185. Epub 2013 Feb 13.
PURPOSE: There is an increasing need for vascular grafts in the field of surgical revascularization. Artificial grafts offer alternative strategies to autologous tissue, however, small caliber (diameter <6 mm) vascular prosthesis are associated with a high incidence of thrombosis and early failure. Despite promising results, vascular tissue engineering is not yet a clinical reality due to the complexity of this approach. We aimed at investigating the use of fibroin, a biodegradable protein derived from silk, as an acellular vascular graft for in vivo recellularization.
METHODS: We produced small caliber fibroin matrices by electrospinning to replace small arterial segments. Electrospun fibroin scaffolds were implanted into the abdominal aorta of Lewis rats by end- to-end anastomosis. Seven days after implantation, fibroin matrices were recovered and processed for histological and immunohistochemical analysis.
Fibroin matrices allowed host cell infiltration, extracellular matrix remodeling, and ensured good patency of the grafts in the short term. Endothelial cells and smooth muscle cells were present in the explanted construct. Development of an elastic lamina adjacent to the lumen of the scaffold was observed with organization of intima and media layers. Vasa-vasorum were also present in the outer layer of the fibroin material.
CONCLUSIONS: Our results indicate that formation of vascular tissue containing elastin occurs already at 7 days after implantation on fibroin scaffold without in vitro cellularization. The use of an acellular electrospun silk fibroin tubular scaffold could be a promising strategy for in vivo regeneration of vascular tissue in the clinical reality.
在外科血管重建领域，对血管移植物的需求日益增加。人工移植物为自体组织提供了替代策略，然而，小口径（直径<6mm）血管假体与高血栓形成发生率和早期失败相关。尽管有 promising 的结果，但由于这种方法的复杂性，血管组织工程尚未成为临床现实。我们旨在研究丝素蛋白（一种源自蚕丝的可生物降解蛋白质）作为无细胞血管移植物用于体内再细胞化的用途。
我们通过静电纺丝制备小口径丝素蛋白基质以替代小动脉段。将静电纺丝的丝素蛋白支架通过端端吻合植入 Lewis 大鼠的腹主动脉。植入后 7 天，回收丝素蛋白基质并进行组织学和免疫组织化学分析。
丝素蛋白基质允许宿主细胞浸润、细胞外基质重塑，并在短期内确保移植物的良好通畅性。在取出的构建体中存在内皮细胞和平滑肌细胞。观察到与支架管腔相邻的弹性膜的发育以及内膜和中膜层的组织化。血管滋养管也存在于丝素蛋白材料的外层。
我们的结果表明，在没有体外细胞化的情况下，在植入丝素蛋白支架后 7 天就已经发生了含弹性蛋白的血管组织的形成。使用无细胞静电纺丝丝素蛋白管状支架可能是临床现实中血管组织体内再生的一种有前途的策略。
