自体脂肪干细胞复合珊瑚修复犬颅骨标准缺损的初步研究

Tissue-engineering bone with ADSCs and coral scaffold for repairing of cranial bone defect in canine

目的应用自体脂肪干细胞（adipose-derived stem cells，ADSCs）复合珊瑚构建组织工程化骨，修复犬颅骨标准缺损。方法体外扩增培养、成骨诱导Beagle犬ADSCs，将第2代细胞接种在珊瑚支架上共同培养。制造实验犬双侧颅骨全层标准缺损（20mm×20mm），一侧以细胞材料复合物修复作为实验组（n=7），另一侧以单纯珊瑚材料修复作为对照组（n=7）。术后24周分别通过影像学、大体形态观察、生物力学检测、组织学方法检测颅骨缺损的修复效果。结果成骨诱导的犬ADSCs体外呈现成骨特性，在珊瑚支架上生长良好。3D—CT重建显示术后12周实验组有新生骨痂形成，对照组材料大部分降解；24周时实验组为骨性愈合，对照组为骨不连。24周时实验组缺损修复百分比为（84．19±6．45）％，显著高于对照组的（25．04±18．82）％（P〈0．01）。大体观察见实验组由新生骨痂修复缺损，对照组缺损边缘可见少量骨痂形成，主要为软组织充填；24周生物力学检测修复组织能耐受的最大压力载荷，实验组为（73．45±17．26）N，为犬顶骨最大压力负荷（104．27±22．71）N的70％，两者比较差异有统计学意义（P〈0．01），对照组为软组织无法完成上述检测。HE染色见实验组有较多成熟骨呈骨性愈合，对照组为纤维性愈合。结论自体成骨诱导的ADSCs复合珊瑚形成的组织工程化骨可修复犬颅骨标准缺损。

Objective To investigate the application of tissue-engineering bone with ADSCs （adiposederived stem cells） and coral scaffold for repairing of cranial bone defect in canine. Methods Autologous ADSCs isolated from canine subcutaneous fat were expanded, osteogenically induced, and seeded on coral scaffolds. Bilateral full-thickness defects（20 mm × 20 mm） of parietal bone were created （ n = 7）. The defects were either repaired with ADSC-coral constructs （experimental group） or with coral alone （control group）. Radiological, gross, biomechanical and histological observations were done to evaluate the bone regeneration. Results Three-dimensional CT scan showed that new bones were formed in the experimental group at 12 weeks after implantation, while coral scaffolds were partially degraded in the control group. By radiographic analysis at 24 weeks post-transplantation, it showed that an average repair percentage of each defect was （84.19 ± 6.45）% in experimental group, and （25.04 ± 18.82）% in control group（ P 〈 0.01 ）. The maximum compression loading was （73.45 ± 17.26） N in experimental group, and （104.27 ± 22.71） N in control group （P 〈 0.01）. Histological examination revealed that the defect was repaired by typical bone tissue in experimental group, while only minimal bone formation with fibrous eonnection in the control group. Conclusions The tissue-engineering bone with autologous osteogenie ADSCs and scaffold could successfully repair the cranial defects in canine models.