骨髓内皮细胞衬里人工血管间置移植的实验研究

Seeding of ePTFE Prostheses Interposition Grafts with Bone Marrow-derived Endothelial Cells in Dogs

通过骨髓内皮细胞衬里人工血管间置移植的动物实验,为人工血管内皮化的临床应用作准备。方法:分离犬骨髓单核细胞,ePTFE人工血管以二种规格(4mm×4cm和8mm×5cm)完成内皮化。分别作犬颈总动脉和下腔静脉间置移植(各10条),术后作多谱勒超声检查,处死后作移植血管大体肉眼、病理、免疫组化、扫描电镜等检查。结果:颈总动脉移植组:2周和2月实验侧通畅率分别为100%(5/5)和60%(3/5),同期对照侧通畅率分别为40%(2/5)和0%(0/5);下腔静脉移植组:实验组和对照组2月移植血管通畅率为83.3%(5/6)和50%(2/4)。扫描电镜显示:颈总动脉移植血管腔面内皮细胞覆盖率实验组和对照组2周时存在差异(84%±11%与43%±15%,P<0.05),下腔静脉移植实验组和对照组内皮细胞覆盖率也有差异(95%±6%与77%±13%,P<0.05);颈总动脉和下腔静脉移植物2月时,血管内膜厚度实验组小于对照组(116±28μm与162±30μm,P<0.05;91±24μm与143±35μm,P<0.05)。结论:骨髓内皮细胞衬里的ePTFE人工血管在体内能较快完成内皮化过程,能抑制内膜增生;循环内皮细胞作为内皮细胞的潜在来源,具有一定临床应用价值。

To evaluate the value of circulating endothelial cells as the resource of endothelialization, by seeding of ePTFE prostheses interposition grafts in dogs, making prepare for endothelialization of ePTFE in vivo. Methods: Dog bone marrow monocytes were isolated by centrifugation. The procedure of endothelial lining ePTFE prostheses(4 mm×4 cm and 8 mm×5 cm)were finished and interposed in carotid artery and inferior vena cave in 20 dogs. Doppler ultrasound were performed before animal were killed 2 weeks and 2 months after surgery, and graft segments were grossly evaluated and then under pathological examination, immunocytochemistry observation and scanning electron microscopic analysis.Results: Patency rates for seeded grafts in carotid artery group were 100%(5/5)and 60%(3/5)at 2 week and 2 month respectively, control grafts had a patency rate of 40%(2/5)and 0%(0/5)at corresponding times; Patency rates for seeded grafts in inferior vena cava group were 83.3%(5/6)and 50%(2/4)at 2 month in experiment grafts and control grafts respectively .Scanning electron microscopy showed endothelial cells coverage rates were different between experiment and control groups at carotid grafts(2 month)(84%±11% vs 43%±15%, P <0.05),so did at inferior vena cava(95%±6% vs 77%±13%, P <0.05). Neointimal thickness was thinner in experiment grafts as compared with those of control grafts at 2 month(116±28 μm vs 162±30 μm, P <0.05; 91±24 μm vs 143±35 μm, P <0.05).Conclusion: Lining ePTFE protheses with bone marrow-derived endothelial cells facililated luminal endothelialization and induced less chronic intimal proliferation; As the potential source, circulating endothelial cell had definite value in the endothelialization of protheses in vivo.