背景:目前,小径人工血管移植后由于缺乏内皮细胞衬里和抗血栓特性,长期通畅率低.有研究尝试用成熟内皮细胞种植人工血管以增强其抗血栓能力,以提高长期通畅率,但由于种子细胞和支架材料存在的缺陷,其效果并不令人满意.因此,临床上亟需寻找合适的种子细胞及血管支架材料,改善小径人工血管移植长期通畅率低这一现状.目的:探讨体外诱导骨髓单个核细胞分化成为内皮祖细胞的可行性,并种植聚氨酯小径人工血管表面,为小径聚氨酯人工血管内皮化提供合适的种子细胞.设计:观察性实验.单位:中山大学附属第一医院心血管医学部,免疫学教研室.材料:实验于2004-09/2005-05在中山大学附属第一医院完成.健康志愿者成人骨髓(n=7)约10 mL.方法:收集健康成人骨髓单个核细胞,置于纤维连接蛋白预衬的DMEM培养基中,用血管内皮生长因子和碱性成纤维细胞生长因子加以诱导,通过荧光显微镜和免疫组化分析等方法观察和鉴定诱导后的细胞.将诱导分化的内皮祖细胞种植到聚氨酯小径人工血管表面,用扫描电镜观察.主要观察指标:①细胞形态学变化.②免疫组化VWF和CD34抗体染色结果.③聚氨酯小径人工血管表面内皮祖细胞的黏附生长状态.结果:①在血管内皮生长因子和碱性成纤维细胞生长因子等诱导因子存在的条件下,骨髓单个核细胞分化成为内皮祖细胞,倒置荧光显微镜下呈典形的"纺锤样"梭形细胞,单层细胞贴壁生长融合时呈铺路石样排列.②免疫组化示VWF和CD34抗体染色阳性.②扫描电镜下,未种植细胞的聚氨酯小径人工血管表面呈典型的多孔蜂窝状结构,孔径大小比较适合内皮祖细胞爬行.种植细胞后,聚氨酯小径人工血管表面有大量的内皮祖细胞黏附、爬行及铺展生长,有时可见内皮祖细胞长入蜂窝状孔径内.结论:在体外能将骨髓单个核细胞诱导分化成为内皮祖细胞,而诱导分化的内皮祖细胞在小径聚氨酯人工血管上黏附生长状态良好,提示体外诱导骨髓单个核细胞分化为内皮祖细胞可作为小径聚氨酯人工血管内皮化的种子细胞.%BACKGROUND: At present, after transplantation of small diameter artificial blood vessel, long-term patency rate is low due to being lacking of endothelial cells for lining and anti-thrombus characters. In some studies,mature endothelial cells were tried to be seeded in the artificial vessel to boost up its anti-thrombus capability so as to improve the long-term patency rate, but we got unsatisfied effect due to the defects of seed cells and scaffolds. Therefore, in clinic, proper seed cells and vascular scaffolds have been searched for improving the long-term low pateney rate in transplantation of small diameter artificial blood vessel.OBJECTIVE: To investigate the feasibility that differentiation of bone marrow mononuclear cells induced in vitro into endothelial-progenitor cells (EPCs) and seed polyurethane small diameter artificial blood vessel so as to provide proper seed cells for endotheliazation of polyurethane small diameter artificial blood vessel.DESIGN: Observation experiment SETTING: Cardivascular Medical Department and Staff Room of Immunology, First Hospital Affiliated to Sun Yat-sen University MATERILAS: This experiment was carried out at the First Hospital Affiliated to Sun Yat-sen University from September 2004 to May 2005. About 10 mL of bone marrow from healthy adult volunteers (n=7) was used in this experiment.METHODS: Bone marrow mononuclear cells of healthy adult were collected and put in the fibronectin pre-coated DMEM culture medium, then induced by vascular endothelial growth factor and basic fibroblast growth factor. Induced cells were observed under fluorescence microscope and identified with immunohistochemical staining. The induced and proliferated EPCs were seeded onto the surface of polyurethane small diameter artificial blood vessel. Morphological change was observed under scanning electron microscope.MAIN OUTCOME MEASURES: ① Cellular morphological change.② Staining results of immunohistochemical VWF and CD 34 antibody . ③ Adhesive growth status of EPCs on the polyurethane small diameter artificial blood vessel RESULTS: ① In the vascular endothelial growth factor and basic fibroblast growth factor and other inducers , bone marrow mononuclear cells differentiated into EPCs , presenting typical "spindle-shaped" appearance under an inverted fluorescence microscope and became to form a monolayer that arrayed in "cobblestone-like" ② Immunohistochemical staining showed von willebrand factor(VWF) and CD34 antigen stained positive. ③ Under the scanning electron microscope, surface of polyurethane small diameter artificial blood vessel without seeded cells presented typical polyporous honeycomb-like structure , and the size of hole suited the crawling of EPCs. After seeding the cells, we observed the adhesion, crawling and spreading of the EPCs on the surface of polyurethane small diameter artificial blood vessel. Some EPCs grew into the honeycomb-like holes were seen occasionally.CONCLUSION: Bone marrow mononuclear cells can be induced and differentiated into EPCs, while induced and differentiated EPCs well grow adhesively in the polyurethane small diameter artificial vessels, suggesting that differentiation of bone marrow mononuclear cells induced in vitro into EPCS, which can be used as seed cells for endothelialization of polyurethane small diameter artificial blood vessels.
展开▼
