磷酸三钙复合骨形态发生蛋白-2/血小板衍生生长因子-BB修复SD大鼠颅骨标准骨缺损

摘要

Objective To observe the effect of a new biomaterial in promoting the bone regeneration for repairing critical-size cranial defects in SD rats. Methods Critical-size cranial defects were induced in 3-month-old male Sprague-Dawley rats and repaired with the implants of calcium phosphate from growth factor enhanced matrix 21 (CaPfromGEM21, control), CaPfromGEM21 preloaded with 10 ng bone morphogenetic protein-2 (BMP-2), CaPfromGEM21 preloaded with 100 ng BMP-2, CaPfromGEM21 preloaded with 0.3μg platelet-derived growth factor-BB (PDGF-BB), or CaPfromGEM21 preloaded with 3μg PDGF-BB. The defects were examined 6 weeks after the surgery with X-ray, micro-CT, HE staining and quantitative assessments. Results X-ray showed defect repair in all the groups. The fracture line became obscure, and the defects were almost fully repaired by the regenerated bone tissues in PDGF-BB group. Micro-CT demonstarted new bone formation in the defects. The new bone volume was significantly greater in PDGF-BB groups than in BMP-2 groups (P<0.05). HE staining revealed the presence of new bones in the defects and new vessels in and around the new bones without inflammatory cells. The new bone area fraction was significantly greater in 10 ng BMP-2 group and 0.3 μg PDGF-BB group than in the control group (P<0.05), and the new vessel density was similar in the all the 4 cytokine-preloaded groups and all significantly greater than that in the blank and CaPfromGEM21 control group (P<0.05). Conclusion CaPfromGem21 combined with BMP-2 or PDGF-BB has good biocompatibility and can better promote bone regeneration for repairing bone defects.%目的：观察新型生物功能化复合材料在SD大鼠颅骨标准骨缺损中再生修复作用，为骨生物材料的基础研究、成骨及成血管提供实验资料。方法3月龄雄性SD大鼠颅骨标准缺损模型随机分入不同实验组，观察时间6周。实验分为CaPfromGEM21、CaPfromGEM21+10 ng 复合了骨形态发生蛋白-2（BMP-2）、CaPfromGEM21+100 ng BMP-2、CaPfromGEM21+0.3μg血小板衍生生长因子（PDGF）-BB、CaPfromGEM21+3μg PDGF-BB和空白组。对标本行X线、Micro CT，苏木素-伊红染色（HE染色）及相关的定量分析。结果 X线影像提示各组骨缺损均有不同程度的修复，骨折线逐渐模糊，PDGF-BB组的骨缺损基本修复。Micro CT可见各组骨缺损均有不同程度新生骨长入。新生骨体积定量结果提示添加PDGF-BB组新生骨明显多于BMP-2实验组（P<0.05），具有统计学意义。HE染色切片各组均未见急慢性炎症细胞浸润，缺损中可见染色均一的新生骨组织，新生骨内及周围可见散在的新生血管，新生骨面积百分数提示10 ng BMP-2组新生骨面积百分数及0.3μg PDGF-BB组新生骨量百分数均明显大于单纯材料组（P<0.05），新生血管密度定量提示4个添加因子的实验组的新生血管密度均明显大于空白组及单纯材料组（P<0.05），4个添加因子的实验组之间差异无统计学意义（P>0.05）。结论 CaPfromGEM21复合BMP-2/PDGF-BB具有良好的生物相容性，骨缺损修复效果优于单纯材料植入，有望成为理想的新型骨再生修复替代材料之一。