血管平滑肌细胞和内皮细胞联合种植生物可降解材料的组织工程血管研究

目的探讨应用组织工程学方法构建人工血管片。方法应用聚(乙交酯/丙交酯)二元共聚物(PLGA)无纺网织片作为细胞支架,体外逐层顺序种植血管平滑肌细胞、内皮细胞制作组织血管片。免疫组织化学方法鉴定平滑肌细胞、内皮细胞;扫描电镜观察组织血管片生长情况;放射免疫方法检测内皮细胞分泌内皮素、前列腺素E的功能。结果免疫组织化学染色鉴定平滑肌细胞肌动蛋白染色阳性,内皮细胞凝血Ⅷ因子相关抗原染色阳性。组织血管片在扫描电镜下显示出细胞融合,连接成片。放射免疫方法可以检测出平滑肌细胞和内皮细胞联合培养的组织片分泌内皮素(229pg/ml±34pg/ml),分泌前列环素的代谢产物6-酮-前列腺素F1α(402pg/ml±108pg/ml)。结论应用PLGA无纺网织片作为细胞支架,体外逐层种植血管平滑肌细胞、内皮细胞制作的组织血管片,基本具备正常血管组织基本形态结构和功能。

Blood vessel tissue engineering: seeding vascular smooth muscle cells and endothelial cells sequentially on biodegradable scaffold in vitro

OBJECTIVE: To evaluate the effect of seeding vascular smooth muscle cells and endothelial cells sequentially on biodegradable scaffold in vitro. METHODS: Venous endothelial cells and smooth muscle cells of artery were isolated from the umbilical cord of newborn and cultured in vitro. The cultured arterial smooth muscle cells and cultured endothelial cells were seeded on the polyglycolic acid and polylactide (PLGA) nonwoven mesh as tissue scaffolds respectively (group A and group B). And cultured endothelial cells were seeded on the scaffold already seeded with smooth muscle cells sequentially to construct vascular patch (group C). One month after cultivation the patches of the 3 groups underwent HE staining and microscopic examination and scanning electron microscopy. Immunohistochemistry was used to examine the existence of actin and factor VIII-related antigen, secreted by endothelial cells, in the cells. The levels of endothelin and 6-Keto-PGF1alpha in the culture solution were examined by means of radioimmunology so as to measure the endothelial function. Pure culture solution was used as blank control (group D). RESULTS: Microscopy showed that cells were fused into patch in the group C. HE staining showed that the smooth muscle cells were embedded into the PLGA scaffold and grew in multiple layers covered by a layer of endothelial cells on the surface. The types of cells could be identified by immunohistochemical procedure. The levels of endothelin and 6-Keto-PGF1alpha in the culture solution were 229 pg/ml +/- 34 pg/ml and 402 pg/ml +/- 108 pg/ml respectively in the group C, and 200 pg/ml +/- 31 pg/ml and 336 pg/ml +/- 121 pg/ml in the group B, both significantly higher than those in the groups A and D (blank control group, all P < 0.05 or P < 0.05). CONCLUSION: Tissue engineering blood vessel with normal morphological and functional characters to a certain degree can be constructed through seeding cultured vascular smooth muscle cells and endothelial cells sequentially on PLGA scaffold.