rFN/CDH-BCP组织工程骨的制备和体内融合效应的初步研究

摘要

Objective To study the healing response of a tissue engineered bone of bMSCs combined rFN/CDH-BCP in a rabbit model. Methods The biomimetic surface was achieved by immobilizing rFN/CDH onto biphasic calcium phosphate ceramic ( BCP) covalently. The effect of rFN/CDH-BCP on adhesion,proliferation and differentiation were evaluated comprehensively by using cell centrifugal adhesive as-say,MTT method,SEM,Alkaline phosphatase ( ALP) activity and alizarin red staining respectively. A rabbit lumbar fusion model was estab-lished by implanting bMSCs combined rFN/CDH-BCP into intertransverse process space of L4 ~L5 ,the fusion site bone formation was ob-served by imaging means,histological techniques was used to observe the new bone formation and distribution of seed cells. Results Cell centrifugal adhesive assay indicated the adherent bMSCs on rFN/CDH-BCP associated with the ligand density,the biomimetic surface posses-ses excellent biocompatibility. The ALP activity on rFN/CDH-BCP surface was the highest among all samples on the 10th day after induction (P<0. 05). On the 21st day,alizarin red staining showed that the oval-shaped and orange-red nodules,either the number or the area,distrib-uted wider on rFN/CDH-BCP surface. The results from X plain after 3 months revealed a fuzzy gap between material and bone bed,and higher cover rate of intertransverse process space with new bone deposition on rFN/CDH-BCP surface. Conclusion Histologically,rFN/CDH-BCP exhibited as interlacing bone trabecula bridging biomaterial suface and cortical bone of transverse process continously. The bone mass was much more than the ture BCP class. The comprehensive data reveals that when loaded with MSCs,rFN/CDH-BCP demonstrates superior char-acteristics of osteoconduction and osteoinduction,and substantially enhances healing capacity in vivo.%目的制备复合bMSCs的rFN/CDH-BCP组织工程骨,并对其体内融合效应进行初步观测。方法制备复合bM-SCs的rFN/CDH-BCP组织工程骨,利用细胞离心粘附实验、MTT实验和成骨诱导分化等方法观察组织工程骨界面对骨种子细胞的粘附和分化的影响。建立兔腰椎横突间植骨融合模型,以复合bMSCs的rFN/CDH-BCP组织工程骨植于预备的骨槽内,利用X线影像学和组织学技术观察融合部位新骨生成状况及种子细胞分布、转归状况。结果 bMSCs复合24 h后rFN/CDH-BCP表面和内部有大量细胞粘附,生长良好,成骨诱导10 d后,rFN/CDH-BCP表面ALP活性显著升高(P<0.05),21 d后,钙结节广泛分布。 bMSCs复合rFN/CDH-BCP植入兔植骨融合区12周后X线和组织学显示有明显新生骨生成,对照组没有。结论 rFN/CDH-BCP组织工程骨在体内外均有良好的生物学效应,对新骨形成和骨成熟具有显著的促进作用和良好修复作用,具有较广阔的临床应用前景。