Combined Effect of Noggin Suppression and Nell-1 on Bone Regeneration

Noggin 抑制和 Nell-1 对骨再生的联合作用

• 批准号: 8184767
• 负责人: Min Lee
• 金额: $ 34.65万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-25 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8184767
• 关键词: Adverse effects; Autologous; BMP2 gene; Biological; Biological Models; Biomimetics; Bone Morphogenetic Proteins; Bone Regeneration; Bone Transplantation; Calvaria; Cells; Clinical; Complement; Cyst; Defect; Development; Dose; Down-Regulation; Elements; Employment; Environment; Epidermal Growth Factor; Exhibits; Feedback; Fracture; Goals; Gold; Growth Factor; Healed; In Vitro; Marrow; Mechanics; Mediating; Mesenchymal Stem Cells; Methods; Modality; Modeling; Morbidity - disease rate; Natural regeneration; Osteoblasts; Osteogenesis; Pathway interactions; Physiological; Proteins; RNA Interference; Research; Signal Transduction; Site; Small Interfering RNA; Spinal Fusion; Stem cells; System; Testing; Therapeutic; Tibial Fractures; Tissues; Transplanted tissue; Vesicle; Viral; base; bone; healing; in vivo; inhibitor/antagonist; long bone; maxillofacial; non-viral gene delivery; novel; osteoblast differentiation; osteogenic; osteoinductive factor; osteoprogenitor cell; polyarginine; protein expression; relating to nervous system; repaired; scaffold; uptake

DESCRIPTION (provided by applicant): The current "gold standard" for bone graft material is autologous bone graft, but autologous grafts are limited by availability and donor site morbidity. Various osteoinductive growth factor-based therapies have been developed in an attempt to find an effective and safer method of bone regeneration. Among the various osteoinductive factors available, bone morphogenetic proteins (BMPs) are believed to be the most potent osteoinductive factors and have been extensively studied for the treatment of many bone fractures and bone defects. However, BMPs are highly pleiotropic molecules and their supra-physiological dose requirement leads to adverse side effects such as cyst formation, and inefficient bone formation. Thus, there is a need to develop alternative osteoinductive growth factor strategies that can effectively complement BMP activity to maximize biological efficiency while minimizing the BMP dose. One alternative approach is to deliver no BMP at all, while enhancing the ability of the progenitor cells that participate in regeneration to respond to endogenous BMPs. This can be accomplished by delivering inhibitors of BMP antagonists such as Noggin, thereby enhancing endogenous BMP activities. Noggin is a direct target of BMP pathways in osteoprogenitors, and it is thus highly likely that supraphysiological BMP doses are required clinically in large part due to Noggin induction. Thus, we propose an approach for enhancing BMP signaling through down-regulation of Noggin. The potency of endogenous BMPs can be enhanced by delivering osteoinductive signals that are more specific and less pleiotropic than BMPs, such as Nell-1 [Nel-like molecule-1; Nel (a protein strongly expressed in neural tissue encoding epidermal growth factor like domain)]. In previous studies, Nell-1 has been shown to accelerate osteogenic differentiation in vitro and calvarial bone formation in vivo. Moreover, Nell-1 is a secreted protein that can be delivered extracellularly, and most importantly Nell-1 promotes synergistic effects with BMP2 on bone regeneration. By suppressing Noggin locally, we seek to enhance endogenous BMP signaling which in turn, should synergistically stimulate osteoblast differentiation induced by Nell-1, thereby leading to maximum bone formation without the concerns surrounding BMP mediated adverse effects. The specific hypothesis of this proposal is that controlled delivery of Nell-1 combined with the employment of Noggin suppression can enhance repair of segmental femoral defects. Two specific aims are proposed to investigate this hypothesis. Aim 1: To enhance bone regeneration via Noggin suppression + Nell-1. In this specific aim, we will evaluate synergistic effects of Nell-1 combined with Noggin-suppressed MSC on osteogenic capacity and bone regeneration. Aim 2: To enhance bone regeneration via controlled delivery of Noggin-siRNA + Nell-1. In this aim, we will develop non-viral gene delivery/scaffolding systems that release Nell-1 and Noggin-siRNA and will test whether they can effectively regenerate bone in a segmental femoral defect model. PUBLIC HEALTH RELEVANCE: This research will contribute to the development of alternative therapeutic strategies that can effectively complement BMP activity in clinical situations where maximal bone regeneration is required.

描述（由申请人提供）：骨移植物材料的当前“黄金标准”是自体骨移植物，但自体移植受可用性和供体部位发病率的限制。已经开发了各种基于骨诱导的生长因子疗法，以寻找一种有效，更安全的骨再生方法。在可用的各种骨诱导因子中，据信骨形态发生蛋白（BMP）是最有效的骨诱导因子，并且已经广泛研究以治疗许多骨折和骨缺损。然而，BMP是高度多效性分子，其上生理剂量的需求会导致不良副作用，例如囊肿形成和骨骼效率低下。因此，有必要开发替代的骨诱导生长因子策略，这些策略可以有效地补充BMP活性以最大程度地提高生物学效率，同时最大程度地减少BMP剂量。 一种替代方法是根本没有提供任何BMP，同时增强了参与再生对内源性BMP反应的祖细胞的能力。这可以通过传递Noggin等BMP拮抗剂的抑制剂来实现，从而增强内源性BMP活性。 Noggin是骨基因生成剂中BMP途径的直接靶标，因此很有可能在临床上很有可能在临床上造成Noggin诱导，因此很可能需要临床。因此，我们提出了一种通过下调Noggin来增强BMP信号传导的方法。可以通过传递比BMP（例如NELL-1 [NEL样分子-1）更具体且更少的多效性来增强内源性BMP的效力。 NEL（一种在编码表皮生长因子（如域）的神经组织中强烈表达的蛋白）。在先前的研究中，NELL-1已被证明可以在体内加速体外和颅骨形成的成骨分化。此外，NELL-1是一种分泌的蛋白质，可以细胞外递送，最重要的是NELL-1促进了BMP2对骨再生的协同作用。通过局部抑制Noggin，我们寻求增强内源性BMP信号传导，而内源性BMP信号转导，应协同刺激NELL-1诱导的成骨细胞分化，从而导致最大的骨形成，而不会引起BMP介导的不良影响。该提案的具体假设是，NELL-1的控制递送与Noggin抑制的使用相结合可以增强股骨缺陷的修复。提出了两个具体的目的来研究这一假设。目标1：通过Noggin抑制 + NELL-1增强骨再生。在这个具体目的中，我们将评估NELL-1与Noggin抑制的MSC对成骨的能力和骨骼再生的协同作用。目标2：通过控制递送Noggin-SiRNA + NELL-1来增强骨再生。在此目标中，我们将开发非病毒基因递送/脚手架系统，以释放Nell-1和Noggin-SiRNA，并将测试它们是否可以在股骨缺陷模型中有效再生骨骼。 公共卫生相关性：这项研究将有助于开发替代性治疗策略，这些策略可以有效地补充需要最大骨再生的临床情况下的BMP活动。