背景:3-羟基丁酸-4-羟基丁酸共聚酯(P3HB4HB)是近年来受到重视的聚羟基脂肪酸酯族组织工程支架材料,具有良好的生物相容性和细胞黏附性以及优良的力学性能,在组织工程研究领域显示出良好的应用前景。目的:验证P3HB4HB支架材料与人骨髓间充质干细胞的体外生物相容性及体内异位成骨能力。方法:(1)将第5代人骨髓间充质干细胞种植于P3HB4HB三维支架上使用成骨诱导液培养5 d,采用吖啶橙荧光染色及扫描电镜观察细胞在支架上的生长情况;(2)将第5代人骨髓间充质干细胞种植于P3HB4HB支架上体外使用成骨诱导液培养为实验组,不使用成骨诱导液培养为对照组,两组培养14 d后分别植入裸鼠皮下,植入后16周时取出行苏木精-伊红染色,Vonkossa染色和Ⅰ型胶原免疫组化染色检测植入物体内异位成骨情况。结果与结论:(1)吖啶橙荧光染色显示细胞黏附于支架材料表面,生长良好;(2)扫描电镜观察成骨诱导的人骨髓间充质干细胞在P3HB4HB支架上生长良好,细胞产生丰富的细胞外基质;(3)植入16周时大体观形成骨样组织,Vonkossa染色、Ⅰ型胶原染色呈阳性,苏木精-伊红染色见较多成骨细胞,有典型的骨陷窝出现,对照组无骨组织形成;(4)研究表明P3HB4HB适合作为骨组织工程支架材料。
BACKGROUND: As a noticeable tissue engineering material of polyhydroxyalkanoates family, poly(3-hydroxybutyrate-co-4-hydroxybutyrate)(P3HB4HB)exhibits good biocompatibility, adhesion and mechanical properties, presenting a extensive application future in tissue-engineered research. OBJECTIVE: To investigate the biocompatibility in vitro and ectopic osteogenic differentiation in vivo of P3HB4 HB and human bone marrow mesenchymal stem cells. METHODS: Passage 5 human bone marrow mesenchymal stem cells transplanted onto the three-dimensional P3HB4 HB scaffold were incubated with osteogenic induction medium(test group) or with no osteogenic induction(control group), respectively. After 5-day incubation, the cell growth was assessed by acridine orange staining and scanning electron microscopy; after14-day incubation, both kinds of cell-scaffold composites were subcutaneously implanted into the nude mice. At 16 weeks after implantation, the cell-scaffold composites were removed to observe ectopic osteogenic differentiation in vivo using hematoxylin-eosin staining, von Kossa staining and collagen type I immunohistochemical staining. RESULTS AND CONCLUSION: Acridine orange staining showed that cells adhered well on the surface of the scaffold; under the scanning electron microscope, induced cells grew well on the P3HB4 HB scaffold and produced abundant extracellular matrixes. In addition, at 16 weeks after implantation, there were osteoid tissues in the test group, positive for von Kossa staining as well as collagen type I immunohistochemical staining; furthermore, hematoxylin-eosin staining showed numerous osteoblasts and bone lacunas. In contrast, no bone tissues appeared in the control group. To conclude, P3HB4 HB is a suitable material for bone tissue engineering.