应用液态及凝胶态生物载体材料负载同种异体软骨细胞修复全厚关节软骨缺损

背景:应用固态载体作为细胞支架,修复关节软骨缺损,已有成功经验。尝试将液态载体或凝胶态载体材料复合细胞后注入动物体内,观察该方法的可行性。目的:探讨液态载体或凝胶态载体材料氧化聚乙烯和氧化聚丙烯复合物结合重组人骨形态蛋白2负载同种异体软骨细胞修复全厚关节软骨的可行性。设计:对照实验。单位:威海市立医院骨科,山东省创伤骨科研究所。材料:实验于2001-11/2003-09在山东省创伤骨科研究所实验室进行。健康成年新西兰大白兔36只,体质量2.5～4.5kg,雌雄不限。编号后根据缺损处注入物质的成分随机数字法分成4组,即氧化聚乙烯和氧化聚丙烯复合物结合重组人骨形态蛋白2软骨细胞组、氧化聚乙烯和氧化聚丙烯复合物结合重组人骨形态蛋白2组、氧化聚乙烯和氧化聚丙烯复合物软骨细胞组、空白对照组,每组9只。方法:36只大白兔分组后造关节软骨缺损模型,取同种新西兰大白兔关节软骨细胞,体外培养扩增后与20%氧化聚乙烯和氧化聚丙烯复合物结合重组人骨形态蛋白2混合,移植到缺损处进行修复。各移植组缺损处分别注入氧化聚乙烯和氧化聚丙烯复合物结合重组人骨形态蛋白2负载软骨细胞、氧化聚乙烯和氧化聚丙烯复合物结合重组人骨形态蛋白2、氧化聚乙烯和氧化聚丙烯复合物软骨细胞组。空白对照组:缺损处不做任何处理。移植后4,8,12周对缺损的修复情况进行大体、光镜组织学评估和电镜观察。据Wakitani评分标准,采用盲法对修复质量作出评价。主要观察指标:①软骨缺损修复程度。②软骨细胞的性质形态,基质中胶原性质、数量及排列方式。结果:①移植的氧化聚乙烯和氧化聚丙烯复合物结合重组人骨形态蛋白2负载软骨细胞中的软骨细胞能很好地生长,4周时,缺损区完全填充。8,12周再生组织与周围正常软骨组织外观相似,界限模糊。组织学检查:形成透明软骨,缺损处被修复。②电镜下:8,12周,修复组织中可见多数成熟的透明软骨细胞及其周围排列不规则的、纤细的、均匀的和无周期性的Ⅱ型胶原。空白对照组仅见纤维修复,再生组织缺乏弹性,表面粗糙,不规则。③修复质量评分:氧化聚乙烯和氧化聚丙烯复合物结合重组人骨形态蛋白2负载软骨细胞组和各组相比在各个时期差异均存在显著性,氧化聚乙烯和氧化聚丙烯复合物结合重组人骨形态蛋白2组和氧化聚乙烯和氧化聚丙烯复合物软骨细胞组与对照组相比在各个时期差异均存在显著性[4周:(3.93±1.91),(4.56±1.07),(4.78±1.09),(8.44±1.13)分;8周:(2.80±1.45),(3.24±1.00),(3.33±1.00),(8.44±1.13)分;12周:(2.22±1.10),(3.01±0.69),(3.00±0.71),(9.00±0.87)分,P<0.001],但两组之间在各个时期无显著的差异(P>0.05)。结论:氧化聚乙烯和氧化聚丙烯复合物结合重组人骨形态蛋白2负载同种异体软骨细胞移植能以透明软骨的方式成功修复兔膝股骨髁软骨缺损,并优于单纯的氧化聚乙烯和氧化聚丙烯复合物负载重组人骨形态蛋白2或单纯的氧化聚乙烯和氧化聚丙烯复合物软骨细胞的移植。

Allogenic chondrocytes loaded with liquid or gel biocarrier material in repairing full-thickness rabbit articular cartilage defects

BACKGROUND: It has been successful to repair articular cartilage defects by using solid carrier as cytoskeleton. We tried to transplant liquid or gel carrier materials combined cells into the body of animals, and investigated its feasibility.OBJECTIVE: To investigate the feasibility of homo-transplatation with liquid or gel carrier materials of Pluronic F-127-recombinant human bone morphogenetic protein-2 (rhBMP-2) engineered chondrocytes for the repair of full-thickness rabbit articular cartilage defect.DESIGN: A controlled experiment.SETTINGS: Department of Orthopaedics, Weihai Municipal Hospital;Shandong Institute of Orthopaedics and Traumaology.MATERIALS: The experiments were carried out in the laboratory of Shandong Institute of Orthopaedics and Traumaology from November 2001 to September 2003. Thirty-six healthy adult New Zealand rabbits of 2.5-4.5 kg, either male or female, were divided into four groups according to the method of random number table: Pluronic F-127-rhBMP-2 engineered chondrocytes group, Pluronic F-127-rhBMP group, Pluronic F127 engineered chondrocytes group and blank control group, with 9 rabbits in each group.METHODS: After grouping, the 36 rabbits were made into models of articular cartilage defects. Pluronic F-127-rhBMP-2 was used as a vector of chondrocytes which were obtained from New Zealand rabbits after cultured and amplified in vitro. The mixture of Pluronic F-127, Pluronic F-127-rhBMP-2 and cultured chondrocytes was transplanted into the defects of articular cartilage that had been made previously with φb3.5 mm drill.There was not any treatment in the blank control group. At 4, 8 and 12 weeks postoperatively, the repairing conditions of the defects were evaluated with gross observation and histological observation under light microscope and under electron microscope. The repaire quality was assessed blindly according to the Wakitani scoring standard.MAIN OUTCOME MEASURES: ① Healing of cartilage defects; ② Property and morphology of the chondrocytes, characteristics, number and arrangement of collagens in matrix.RESULTS: ① In the Pluronic F-127-rhBMP-2 engineered chondrocytes group, the transplanted chondrocytes could grow better than those in other groups, the defected areas were completely filled at 4 weeks. The regenerated tissues at 8 and 12 weeks had similar appearance with the surrounding normal cartilage tissue, but vague. Delimitation. The histological examination showed that transparent cartilages formed, and the defects were healed. ② Under electron microscope at 8 and 12 weeks, there were mature transparent cartilages in the repaired tissues, and there were irregularly arranged slight, even and non-periodical collagen Ⅱ in surrounding. In the blank control group, only fibrous repair was observed, the regenerated tissue lacked elasticity with rough surface. ③ Repairing quality score: The scores at each time point in the Pluronic F-127-rhBMP-2 engineered chondrocytes group were significantly different from those in the other groups.Those in the Pluronic F-127-rhBMP-2 engineered chondrocytes group and Pluronic F-127-rhBMP-2 group and Pluronic F-127 engineered chondrocytes group were significantly different from those in the blank control group [4 weeks: (3.93±1.91), (4.56±1.07), (4.78±1.09), (8.44±1.13) points:8 weeks: (2.80±1.45), (3.24±1.00), (3.33±1.00), (8.44±1.13) points; 12 weeks (2.22±1.10), (3.01±0.69), (3.00±0.71), (9.00±0.87) points, P ＜ 0.001],but there were no significant differences between the two groups (P ＞ 0.05).CONCLUSION: The mixture of Pluronic F-127-rhBMP-2 and cultured chondrocytes can repair successfully the cartilage defects of femoral condyle of rabbit knees by means of hyaline cartilage than simple application of Pluronic F-127-rhBMP-2 or Pluronic F-127 engineered chondrocytes.