In vitro and in vivo evaluation of a small-caliber coaxial electrospun vascular graft loaded with heparin and VEGF

INTERNATIONAL JOURNAL OF SURGERY

卷:44

Article

Hu, Yun-Tao¹  Pan, Xu-Dong¹  Zheng, Jun¹  Ma, Wei-Guo¹  Sun, Li-Zhong¹ 

[1] Capital Med Univ, Beijing Inst Heart Lung & Blood Vasc Dis, Beijing Anzhen Hosp, Dept Cardiac Surg, Beijing, Peoples R China

关键词: Vasculargraft;    Electrospun;    Endothelialization;    Antithrombogenic;    Tissue engineering;   

DOI  :  10.1016/j.ijsu.2017.06.077

来源: Elsevier

【 摘 要 】

Introduction: To date, clinically available expanded polytetrafluoro-ethylene (ePTFE) vascular grafts are suboptimal for reconstructing small caliber (D < 6 mm) arteries, owing to thrombosis in early and restenosis in late stage. Our aim in this preliminary study was to fabricate a nano-fibrous vascular graft which was biofunctionalized with VEGF(165) and heparin. The short term performance was evaluated both in vitro and in vivo. Method: Four-mm caliber grafts were prepared by the coaxial-elctrospun technique, which consisted of poly(l-lactide-co-caprolactone) [P(LLA-CL)] collagen and elastin. Heparin and endothelial cell growth factor-165 (VEGF(165)) were encapsulated in the core of the fibrous. Controlled release of the heparin and VEGF(165) were evaluated for 28 days. Endothelial cells were cultured on the electrospun grafts or ePTFE grafts as controls. The cellular adhesion, proliferation and morphology were examined. Electrospun or ePTFE grafts were randomly implanted into a rabbit infrarenal aortic replacement model (n = 30) for 28 days without any antiplatelet therapy. At the termination, all grafts were examined by Doppler ultrasound and then evaluated with histology and scanning electron microscopy. Results: The cumulative release amount of heparin (6.93 +/- 1.03 mg) and VEGF165 (22.17 +/- 5.56 mu g) during 28 days were measured. Endothelial cells cultured on electrospun grafts showed significantly higher attachment efficiency and proliferation compared to the ePTFE ones (P < 0.001). At 2 h more ECs had attached to the P(LLA-CL)/Collagen/Elatin grafts (83.26 +/- 8.02%) compared to P(LLA-CL) (67.07 +/- 4.16%) and ePTFE (46.87 +/- 8.85%). ECs proliferated faster on VEGF loaded grafts (O.D = 2.9 +/- 1.2, n = 12) compared to ePTFE (O.D = 1.7 +/- 1.0, n = 12). The patency was significantly higher in electrospun grafts (86.6%) than ePTFE grafts (40.0%) (P = 0.021). Correspondingly, the microscope images of electrospun implants showed little thrombus when compared with the ePTFE implants. Conclusion: Biofunctionalized electrospun graft showed surgical properties, hemocompatibility and higher short-term patency compared with the ePTFE grafts. Despite good early performances, profound study should be designed for long-term evaluation. (C) 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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