脱钙骨支架与诱导培养的脂肪基质细胞复合修复兔胫骨缺损*

背景：脂肪基质细胞经诱导后具备成骨活性已被实验证实，因此，脂肪基质细胞修复骨缺损的研究已成为目前的热点，但脂肪基质细胞修复负重骨缺损修复的相关实验报道较少。 目的：通过兔脂肪基质细胞诱导培养为成骨细胞，并与牛脱钙骨复合培养，对兔胫骨骨缺损修复情况的观察，探讨脂肪基质细胞修复骨缺损的可行性。 设计、时间及地点：随机对照动物实验，于2008-01/09在天津市第三中心医院动物实验室完成。 材料：取新生小牛四肢长骨干干骺端的松质骨置于脱钙液中脱钙、脱脂、去细胞、去抗原和去蛋白等程序处理制备成脱钙骨支架。 方法：选取健康成年新西兰大白兔12只，随机选取1只提取腹腔内脂肪组织15 mL，体外分离培养脂肪基质细胞并行诱导培养证实为成骨细胞后，以1×109 L-1浓度种植于脱钙骨支架上，继续培养1周，制成组织工程骨。将12只新西兰大白兔手术制成双侧胫骨骨缺损模型，左下肢植入单纯脱钙骨作为对照组，右下肢植入组织工程骨作为实验组。 主要观察指标：X射线、CT检查观察骨缺损处骨痂形成情况，取材后行大体、组织学观察骨缺损处修复情况。 结果：大体观察及X射线显示实验组术后12周骨缺损区缺损消失，已骨性愈合，对照组术后12周骨缺损区缺损仍存在，未见完全愈合。组织学观察显示实验组术后12周可见新生骨小梁形成，对照组术后12周未见新生骨小梁形成。测量CT值行配对t检验显示实验组明显优于对照组(P < 0.05)。 结论：脂肪基质细胞经诱导培养具备成骨活性，与细胞支架复合具备修复骨缺损的能力。 关键词：脂肪基质细胞；诱导培养；脱钙骨；骨缺损

Reparation of tibial defects using adipose-derived stromal cells combined with bovine decalcified bone in rabbits

BACKGROUND: Previous studies confirmed that adipose-derived stromal cells have bone activeness after induction. Therefore, it attracts a lot of attention in the context of repair bone damage with adipose-derived stromal cells. However, the reports regarding repairing bone defects in a heavy load area with adipose-derived stromal cells are few. OBJECTIVE: To explore the feasibility of adipose-derived stromal cells in repairing loaded bone defects through observing the repair of rabbit tibial bone defects with adipose-derived stromal cells that was cultured to osteoplast and bovine decalcified bone composite. DESIGN, TIME AND SETTING: The randomized control animal experiment was performed at the animal laboratory of Tianjin Third Central Hospital from January to September 2008. MATERIALS: The demineralized bone was prepared with cancellated bone of metaphysis from newborn calf via treatment of decalcification, defatting, acellular, remove antigen, and deproteinization. METHODS: Twelve adult, healthy, New Zealand white rabbits. One animal was randomly selected, 15 mL intra-abdominal adipose tissue was extracted, cultured and in vitro induction to osteoblasts, followed by plantation on demineralized bone scaffold with density of 1×109 /L, and continue to cultivate a week to produce tissue-engineered bone. The 12 rabbits were prepared for bilateral tibial bone defects model. The left lower extremity was implanted demineralized bone served as a control group, and the right lower extremity implanted in bone tissue engineering as the experimental group. MAIN OUTCOME MEASURES: X-ray film, CT examination was performed to observe callus formation, and gross observation was used to detect the reparation of defects. RESULTS: Gross observation and X-ray showed that the bone defect disappeared and bone had healing in the experimental group at 12 weeks after operation. But bone defect still existed, without fully healing in the control group. Histological observation showed that bone trabecula had formed in the experimental group, but no new bone formation in the control group at 12 weeks after operation. Line measurement of CT value pair t test showed that the experimental group was significantly better than the control group. CONCLUSION: Adipose tissue-derived stromal cells have osteogenic activity after induction culture, which are able to repair bone defects combined with bovine decalcified bone.