武汉云克隆科技股份有限公司

Abstract: The patency rate of small-diameter tissue-engineered blood vessels is the determinant for their application in coronary artery bypass grafting. The coronary artery is innervated by vagus nerves. The origin of vagus nerves is rich in brain-derived neurotrophic factors (BDNF). We have investigated whether BDNF could improve the patency rate of small-diameter tissue-engineered blood vessels through promoting stem cell homing and paracrine activity. In vitro, we isolated early and late endothelial progenitor cells (EPCs) and found BDNF could promote single clone formation and paracrine function of EPCs, and could also induce the proliferation, migration and differentiation of late EPCs. BDNF could enhance the capturing of EPCs in parallel-plate flow chamber. Flow cytometric analysis and laser-scanning confocal microscope showed BDNF could enhance the mobilization and homing of C57BL/6 mouse EPCs after wire injury. Based on it, BDNF was coupled to the lumen surface of the blood vessel matrix material incubated with collagen through SPDP to construct BDNF-modified small-diameter tissue-engineered blood vessel. The blood vessel patency rate was significantly higher than that of control group 8 weeks after implantation in rats and the endothelialization level was superior to control. These results demonstrate that BDNF can effectively improve patency of small-diameter tissue-engineered blood vessels through stem cell homing and paracrine, and it is expected to play an important role in the construction of substitutes for coronary artery bypass grafting.

摘要： 小直径组织工程血管的通畅率是其在冠状动脉搭桥术中的应用的决定因素。冠状动脉由迷走神经支配。迷走神经富含脑源性神经营养因子（BDNF）。我们研究了BDNF是否可以通过促进干细胞归巢和旁分泌活性来提高小直径组织工程血管的通畅率。体外实验分离早期和晚期内皮祖细胞（EPCs）。发现BDNF可促进EPCs的单克隆形成和旁分泌功能，并能诱导EPCs的增殖，迁移和分化，同时 BDNF可增强平行板流室内EPC的捕获能力。流式细胞术和激光扫描共聚焦显微镜显示BDNF可增强线损伤后C57BL / 6小鼠EPCs的动员和归巢。在此基础上，通过SPDP将BDNF与胶原蛋白共孵育的血管基质材料内腔表面偶联，构建BDNF修饰的小直径组织工程血管。大鼠移植后8周血管通畅率明显高于对照组，血管内皮化程度优于对照组。这些结果表明BDNF可以通过干细胞归巢和旁分泌有效地改善小直径组织工程血管的通畅性，并有望在冠状动脉旁路移植替代物的构建中发挥重要作用。

使用试剂原文信息：The number of PE-CD34/APC-VEGFR-2 positive cells was determined using flow cytometry. Serum VEGF, SDF, and IL-8 levels in injured mice were determined using a VEGF-ELISA kit (R&D Systems, Minneapolis, MN), SDF-1-ELISA kit (Uscn Life Science & Technology Company, USA)  and IL-8-ELISA kit (Jingmei Biotech), respectively.