人工血管可降解材料与种子细胞

The study of cell implantation in degradable vessel scaffold

目的使用可降解材料聚乳酸和聚羟基乙酸二元共聚物[poly （ lactic-co-glycolic acid），PLGA]作为组织工程人工血管支架，探讨种子细胞培养条件，为供临床使用的小口径人工血管研制提供参考。方法以PLGA作为细胞基质，新生儿脐带血管提取的平滑肌细胞和内皮细胞作种子细胞，体外培养4周后，将平滑肌细胞种植到PLGA上，4周后将内皮细胞种植到平滑肌细胞上，再4周后取出含此细胞的血管片段行细胞性质及活性检测，了解细胞在PLGA上的存活及生长状态。结果免疫组化检测人工血管中平滑肌肌动蛋白、内皮细胞Ⅷ因子及CD31、CD34均呈阳性表达，证实接种细胞为平滑肌细胞和内皮细胞；放免法检测PLGA细胞培养液，内皮素和6-酮-前列腺素含量明显高于单纯无血清培养液（P〈0．05），证明种植到PLGA内表面的细胞具有活性；光镜和电镜下接种细胞呈典型的平滑肌细胞、内皮细胞形态特征。结论新生儿脐带血管提取的内皮细胞及平滑肌细胞作为种子细胞，体外培养并种植到PLGA上，短期内仍具有生物活性。

Objective The degradable artificial material--poly（ lactic-co-glycolic acid） （PLGA） was used as the scaf- fold of the tissue engineering blood vessel for ceils implantation, and the better requirement for cell culture was studied. These results may be useful to the manufacture of small diameter tissue engineering blood vessel used in clinical in future. Methods The nonwoven mesh degradable PLGA was used as tissue engineering scaffold. The smooth muscular cell（SMC） and endo- thelial cell （EC） harvested from fetus umbilical blood vessel were collected as the seeding cells. The SMC and EC were culti- vated for 4 weeks respectively in vitro. Then, the SMC was seeded on the surface of the PLGA 4 weeks later, the EC was see- ded on the surface of the SMC layer and PLGA. After another 4 weeks, the artificial blood vessel segment with seeding cells was examined in the cellular quality and activity. Results By immunohistochemical method, all test expressions were positive in staining smooth musle aetin, yon Willebrand,CD31 and CD34. By radioimmunoassay, the levels of endothelin and 6-Keto- PGFla in PLGA cell culture solution were higher than in control soulture （ P 〈0.05 ）. These demonstrated that all cells seeded on PLGA still have cellular activity. All seeding cells showed the typical SMC or EC morphological appearances in light micro- scopic and scarming electric microscopic analyses. Conclusion The results show that the SMC and EC from umbilical vessel, after being cultivated in vitro, as the seeding cells seeded sequentially on the degradable blood vessel scaffold （PLGA） , still possess the cellular activity. This may be useful in further studying the small diameter tissue engineering blood vessel.