应用脱细胞血管基质构建组织工程血管的初步研究

目的： 采用脱细胞处理的猪胸主动脉血管基质作为支架材料，接种人脐带血管内皮细胞，构建组织工程血管。方法: 以新鲜猪胸主动脉为原材料， 1% Triton X-100为脱细胞试剂，制备脱细胞血管基质；采用冷冻干燥和热交联法对脱细胞血管基质进行改性，并进行组织学观察及力学性能测定。用人脐带内皮细胞经培养和扩增后，再与所制备的脱细胞血管基质进行复合培养，光学显微镜及扫描电镜观察内皮细胞生长状况。结果: 1% Triton X-100处理84h的猪胸主动脉，既能完全脱除血管中细胞，同时又完整保留血管基质的三维结构；对脱细胞血管基质冷冻干燥24 h，120 ℃下热交联12 h，能有效提高材料的机械强度，断裂强度可达到1.70 MPa。扫描电镜下可见，脱细胞血管基质与内皮细胞复合培养7 d，已形成典型血管内膜样结构。结论: 经改性后的脱细胞血管基质与内皮细胞具有良好的相容性，用其作为支架材料与内皮细胞复合培养，有望应用于构建组织工程化血管。

Reconstruction of tissue engineering blood vessel via acellular matrix

AIM: To reconstruct the tissue engineering blood vessel by using acellular matrix of porcine thoracic aorta tissue as the scaffold, and by inoculability of vascular endothelial cells (EC) from human umbilical cord vein. METHODS: The porcine thoracic aorta was treated with 1% Triton X-100 for preparing acellular vessel matrix, and the mechanical characterization was in succession modified by freeze-drying and thermal cross-linking techniques. Meanwhile, the mechanics capability of the vessel was measured. The endothelial cells isolated from umbilical cord vein were seeded on the acellular matrix scaffolds by tissue culture in vitro. The structure of acellular matrix was analyzed by light microscopy and scanning electron microscopy. RESULTS: By treatment with 1% Triton X-100 for 84 h, the cells of thoracic aorta were fully come off and the three-dimensional structure of the matrix still remained. After modification by freeze-drying for 24 h and then thermal cross-linking under vacuum at 120 ℃ for 12 h, the tensile strength of the acellular matrix remarkable increased and reached the maximum breaking strength of 1.70 MPa. It was also showed that cultured endothelial cells grew on the surface of acellular matrix for 7 days and the typical structure of vessel- like intimal formation was observed under scanning electron microscopy. CONCLUSION: The acellular matrix and endothelial cells have favorable compatibility. The modified acellular matrix could be a good candidate scaffold for rebuilding the tissue engineering blood vessel.