不同载体对重组人成骨蛋白-1骨诱导活性的影响

背景重组人成骨蛋白-1(rhOP-1)的载体目前仅限于胶原,不同载体对其骨诱导活性的影响还未被证实.目的通过不同材料作为rhOP-1载体的异位骨诱导活性的比较研究,筛选一种较为理想的载体材料.设计完全随机、自身和相互对照研究.地点和对象实验在本中心动物实验室完成,实验对象为96只雄性昆明种小鼠.干预将rhOP-1分别与无活性脱钙骨基质(DBM)、羟基磷灰石(HA)、3种α-聚酯类(PLA,PLA-PEG,PLGA)复合,植入小鼠股部内侧肌间隙,3周后取材,比较5种载体对rhOP-1骨诱导活性的影响.主要观察指标通过组织学检查、碱性磷酸酶(ALP)及钙含量的测定比较新骨的成熟度和成骨率.结果rhOP-1/DBM(A)组、单独植入rhOP-1(F)组和真核表达OP-1注入(对照Ⅵ)组均有骨组织生成.A组可见大量骨小梁、骨髓腔和板层骨,血管和骨髓丰富;F组出现编织骨;对照组Ⅵ见成熟的致密骨组织;其余4组复合组可见间充质细胞增生,未见骨组织;载体部分吸收.ALP水平和Ca含量,各复合组均高于对照组,A组高于其他复合组(F=6.250,P＜0.05);F组与对照Ⅵ差异无显著性意义(F=2.704,P＞0.05);除rhOP-1/DBM组以外,其他各复合组与F组之间差异均无显著性意义(F=0.590,P＞0.05).结论DBM为rhOP-1的良好载体;DBM/rhOP-1对临床上促进骨缺损的修复是十分有利的.

Effects of different carriers on bone-inducing activity of recombinant human osteogenic protein-1

BACKGROUND: The carriers of recombinant human osteogenic protein-1(rhOP-1) are limited to collagen. The effects of different carriers on its bone inducing activity still have not been proved. OBJECTIVE: To find an optimal carrier material for rhOP-1 through a comparative studies of the effects of different materials on the bone-inducing activity. DESIGN: A completely randomized, auto-control and mutual control study was used. SETTING AND PARTICIPANTS: Ninety-six male mice of Kunming species were recruited in this study and the experiment was completed at the Animal Laboratory of our center. INTERVENTION: The materials included inactive decalcified bone matrix ( DBM), hydroxyapatite ( HA ), polylactic acid ( PLA), polylactic acid-polyethylene glycol copolymers (PLA-PEG) and polylactic glycollc acid (PLGA), and they were compounded with rhOP-1 respectively, and were then implanted into the medial intermuscular septum of the thighs of mice for 3 weeks. Then, samples were taken to evaluate the effects of the five materials on bone-inducing activity of rhOP-1.MAIN OUTCOME MEASURE: New bone maturity and osteogenic rate were assessed by histological studies, determination of alkaline phosphatase (ALP) level and calcium content of the entopic new bone.RESULTS: Three weeks after implantation, groups of DBM/rhOP-1 (A), rhOP-1 (F) and Eukaryon expressed OP-1 (control VI) all showed new bone formation. Group A was found to have massive bone trabeculac, marrow cavity, and lamellar bones as well as rich blood vessels and bone marrow. Group F showed appearance of woven bones. In Group VI, there appeared compact bone tissues of maturity. In the rest of the groups, there was proliferation of mesenchymal cells, and part of the materials were absorbed, and no bone was found. ALP level and calcium content were significantly higher in every compound group than in control group, and they were higher in Group A than in other experimental groups( F =6. 250, P ＜0.05). No significant difference was found between group F and control VI( F =2. 704, P ＞ 0. 05). No significant difference was found between Group F and all other compound groups(F=0. 590, P ＞ 0.05).CONCLUSION: ① DBM is an effective carrier for rhOP-1; ② DBM /rhOP-1 is useful to accelerate repairs of bone defects in clinic.