Ansari Sahar, Phark Jin-Ho, Duarte Sillas, Paulino da Silva Maike, Sharifzadeh Navid, Moshaverinia Alireza, Zadeh Homayoun H
Center for Craniofacial Molecular Biology, Ostrow School of Dentistry, University of Southern California, Los Angeles, CA.
Division of Restorative Sciences, Ostrow School of Dentistry, University of Southern California, Los Angeles, CA.
J Biomed Mater Res B Appl Biomater. 2016 Oct;104(7):1465-73. doi: 10.1002/jbm.b.33492. Epub 2015 Aug 7.
Recently we have demonstrated the ability of monoclonal antibodies (mAb) specific for bone morphogenetic protein (BMP)-2 immobilized on different scaffolds to mediate bone formation, a process referred to as Antibody Mediated Osseous Regeneration (AMOR). One of the key properties of regenerated bone is its biomechanical strength, in particular in load-bearing areas. This study sought to test the hypothesis that the biomechanical strength of regenerated bone depends of the mode of regeneration, as well as the scaffold used. Four different scaffolds, namely titanium granules (Ti), alginate hydrogel, anorganic bovine bone mineral (ABBM), and absorbable collagen sponge (ACS) were functionalized with anti-BMP-2 or isotype control mAb and implanted into rat critical-size calvarial defects. The morphology, density and strength of the regenerated bone were evaluated after 8 weeks. Results demonstrated that scaffolds functionalized with anti-BMP-2 mAb exhibited varying degrees of bone volume and density. Ti and ABBM achieved the highest bone volume, density, and strength of bone. When anti-BMP-2 mAb was immobilized on Ti or ABBM, the strength of the regenerated bone were 80% and 77% of native bone respectively, compared with 60% of native bone in sites implanted with rh-BMP-2. Control interventions with isotype mAb did not promote considerable bone regeneration and exhibited significantly lower mechanical properties. SEM analysis showed specimens immobilized with anti-BMP-2 mAb formed new bone with organized structure bridging the crack areas. Altogether, the present data demonstrated that the morphological and mechanical properties of bone bioengineered through AMOR could approximate that of native bone, when appropriate scaffolds are used. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1465-1473, 2016.
最近，我们已经证明，固定在不同支架上的、对骨形态发生蛋白（BMP）-2具有特异性的单克隆抗体（mAb）能够介导骨形成，这一过程被称为抗体介导的骨再生（AMOR）。再生骨的一个关键特性是其生物力学强度，尤其是在承重区域。本研究旨在验证以下假设：再生骨的生物力学强度取决于再生模式以及所用的支架。将四种不同的支架，即钛颗粒（Ti）、藻酸盐水凝胶、无机牛骨矿物质（ABBM）和可吸收胶原海绵（ACS），用抗BMP-2或同型对照mAb进行功能化处理，然后植入大鼠临界大小的颅骨缺损处。8周后评估再生骨的形态、密度和强度。结果表明，用抗BMP-2 mAb功能化的支架呈现出不同程度的骨体积和密度。Ti和ABBM实现了最高的骨体积、密度和骨强度。当抗BMP-2 mAb固定在Ti或ABBM上时，再生骨的强度分别为天然骨的80%和77%，而植入重组人BMP-2的部位再生骨强度为天然骨的60%。用同型mAb进行的对照干预并未促进可观的骨再生，且其力学性能显著较低。扫描电子显微镜分析显示，用抗BMP-2 mAb固定的标本形成了具有组织结构的新骨，桥接了裂隙区域。总之，目前的数据表明，当使用合适的支架时，通过AMOR进行生物工程构建的骨的形态和力学性能可以接近天然骨。©2015威利期刊公司。《生物医学材料研究杂志》B部分：应用生物材料，104B：1465 - 1473，2016。
