骨髓基质细胞和内皮细胞联合种植构建组织工程化骨的初步研究

Construct Tissue-engineered Bone by Co-seeding Marrow Stromal Cells and Endothelial Cells

为阐明骨髓基质细胞和内皮细胞联合种植在生物复合材料上构建组织工程化骨 ,在促进成骨过程、加速局部血管生成中的作用 ,将大鼠骨髓基质细胞和人脐静脉内皮细胞联合种植在左旋聚乳酸 /β-磷酸三钙 (PL L A/β- TCP)多孔复合支架材料上作为实验组 ,仅种植骨髓基质细胞在该材料上作为对照组。将此种有活细胞的复合材料种植于裸鼠大腿后侧肌袋内 ,分别于种植后 1、4、8、12、16周处死动物 ,取出复合材料 ,行组织学检测 ,并用图像处理技术计算实验组和对照组的成骨面积百分比和材料面积百分比 ,观察其变化规律。结果显示 :实验组成骨面积百分比增加比对照组明显加快 ,而材料面积百分比减少比对照组迅速 ;其内毛细血管网形成情况也要明显优于对照组。表明骨髓基质细胞和内皮细胞联合种植于支架材料构建组织工程化骨不仅有利于成骨作用 ,促进新生骨区内部血管网形成 ,还有利于复合材料的降解吸收 ,这在构造组织工程化骨过程中具有重要意义。

To identify the role of co-seeding marrow stromal cells (MSCs) and endothelial cells (ECs) onto biocomposite in constructing tissue-engineered bone for promoting osteogenesis and angiogenesis, we seeded rat marrow stromal cells (rMSCs) and human umbilical vein endothelial cells (hUVECs) onto poly (L-lactic acid)/β-tricalcium phosphate (PLLA/β-TCP) macroporous composite (the test group), and seeded rMSCs onto the same kind of composite (the control group). We implanted these biocomposites into the thighs of nude mice intramuscularly and sacrificed these mice at 1, 4, 8, 12, 16 weeks after implantation, respectively. Biocomposites were taken out and histomorphometry was performed. Image manipulation technology was used to calculate the percentages of new bone area and material area in the test group and control group. We found that the percentage of new bone area of test group increased faster than that of control group, the percentage of material of test group decreased faster than that of control group, and the growth of capillary network of test group was much better than that of control group. These results suggest that co-seeding MSCs and ECs onto scaffold for constructing tissue-engineered bone is beneficial to osteogenesis, to angiogenesis in the prosthesis, and to the degradation of scaffold, and it is of significance in the research of bone tissue engineering.