Metabolic Disorders, Amgen Inc., Thousand Oaks, CA 91320, USA.
J Bone Miner Res. 2011 May;26(5):1012-21. doi: 10.1002/jbmr.307.
Therapeutic enhancement of fracture healing would help to prevent the occurrence of orthopedic complications such as nonunion and revision surgery. Sclerostin is a negative regulator of bone formation, and treatment with a sclerostin monoclonal antibody (Scl-Ab) results in increased bone formation and bone mass in animal models. Our objective was to investigate the effects of systemic administration of Scl-Ab in two models of fracture healing. In both a closed femoral fracture model in rats and a fibular osteotomy model in cynomolgus monkeys, Scl-Ab significantly increased bone mass and bone strength at the site of fracture. After 10 weeks of healing in nonhuman primates, the fractures in the Scl-Ab group had less callus cartilage and smaller fracture gaps containing more bone and less fibrovascular tissue. These improvements at the fracture site corresponded with improvements in bone formation, bone mass, and bone strength at nonfractured cortical and trabecular sites in both studies. Thus the potent anabolic activity of Scl-Ab throughout the skeleton also was associated with an anabolic effect at the site of fracture. These results support the potential for systemic Scl-Ab administration to enhance fracture healing in patients.
治疗性增强骨折愈合有助于预防骨科并发症的发生,如骨折不愈合和翻修手术。骨硬化蛋白是骨形成的负调节剂,用骨硬化蛋白单克隆抗体(Scl-Ab)治疗可导致动物模型中的骨形成和骨量增加。我们的目的是研究 Scl-Ab 在两种骨折愈合模型中的作用。在大鼠闭合性股骨骨折模型和食蟹猴腓骨切开模型中,Scl-Ab 均显著增加了骨折部位的骨量和骨强度。在非人类灵长类动物中愈合 10 周后,Scl-Ab 组的骨折处软骨较少,骨折间隙较小,含有更多的骨和较少的纤维血管组织。这些骨折部位的改善与两项研究中未骨折皮质和小梁部位的骨形成、骨量和骨强度的改善相对应。因此,Scl-Ab 在整个骨骼中的强大的合成代谢活性也与骨折部位的合成代谢效应相关。这些结果支持系统性 Scl-Ab 给药在患者中增强骨折愈合的潜力。