A NOVEL STRATEGY FOR OSTEOPOROSIS GENE THERAPY

骨质疏松症基因治疗的新策略

• 批准号: 6512241
• 负责人: Joanne T Douglas
• 金额: $ 7.18万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-01 至 2004-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6512241
• 关键词: biotechnology; bone metabolism; gene targeting; gene therapy; hormone regulation /control mechanism; human subject; human tissue; immunogenetics; osteoblasts; osteocalcin; osteoclasts; osteoporosis; parathyroid hormones; technology /technique development; transfection /expression vector

DESCRIPTION (Taken from the application): Osteoporosis is a group of diseases of diverse etiology in which the rate of bone resorption by osteoclasts exceeds that of bone formation by osteoblasts, resulting in a reduction in the mass of bone per unit volume. Patients with end-stage, 1ow-turnover osteoporosis do not respond to existing therapies. Osteoblasts in end-stage osteoporosis can be activated by parathyroid hormone (PTH); however, this also invokes an increase in osteoclastic activity that limits the effectiveness of this approach. In this project, we propose to develop a gene therapy method to allow PTH activation of osteoblasts that will have reduced ability to produce RANKL, a key regulator of osteoclastogenesis. We hypothesize that this could be accomplished by employing an intracellular single-chain antibody (sFv) to achieve osteoblast-specific downregulation of RANKL. This approach mandates the use of a gene delivery vehicle, or vector, which can target expression of the sFv specifically to osteoblasts. Capitalizing on the ability of recombinant adenoviral (Ad) vectors to accomplish efficient gene transfer, we hypothesize that Ad-mediated gene delivery can be targeted specifically to osteoblasts. The first Specific Aim is to develop an Ad vector targeted to osteoblasts at the transductional and transcriptional levels. Transductional targeting will be achieved using a bispecific antibody with specificities for the adenovirus fiber protein and an osteoblastrelated marker protein, while transcriptional targeting will be achieved by placing the transgene under the control of the osteoblast-specific osteocalcin promoter. The second Specific Aim is to derive an intracellular sFv to selectively downregulate the expression of RANKL. In the third Specific Aim, we will employ the targeted Ad vector to direct the intracellular expression of this sFv specifically within osteoblasts and will determine whether the downregulation of RANKL results in a reduction in osteoclast recruitment in vitro. The realization of these Specific Aims would establish the feasibility of this approach as a rational strategy for gene therapy in patients with end-stage, low-turnover osteoporosis.

描述（取自应用程序）：骨质疏松症是一组疾病 在破骨细胞的骨吸收速率的多种病因中超过 成骨细胞形成骨的骨，导致质量减少 每单位体积的骨头。终阶段的患者，1 ow骨质疏松症不会 应对现有疗法。末期骨质疏松症中的成骨细胞可能是 被甲状旁腺激素（PTH）激活；但是，这也使人增加 在整骨活性中，限制了这种方法的有效性。在 这个项目，我们建议开发一种基因治疗方法，以允许PTH 激活成骨细胞的活化能力会降低产生RANKL的能力，A 破骨细胞生成的关键调节剂。我们假设这可能是 通过使用细胞内单链抗体（SFV）来完成 实现RANKL的成骨细胞特异性下调。这种方法要求 使用基因输送载体或矢量，该载体可以靶向表达 SFV专门针对成骨细胞。利用重组的能力 腺病毒（AD）向量以实现有效的基因转移，我们假设 该AD介导的基因输送可以专门针对成骨细胞。这 第一个具体目的是开发针对成骨细胞的AD向量 转导和转录水平。转移目标将是 使用具有腺病毒特异性的双特异性抗体实现 纤维蛋白和整骨蛋白的标记蛋白，而转录 通过将转基因放置在控制的控制下，将实现目标 成骨细胞特异性骨钙蛋白启动子。第二个具体目的是得出 细胞内SFV选择性下调RANKL的表达。在 第三个具体目标，我们将采用目标的AD向量来指导 该SFV在成骨细胞内的细胞内表达，将 确定RANKL的下调是否导致减少 体外破骨细胞募集。这些特定目标的实现将 确立这种方法作为基因合理策略的可行性 终阶段，低转变骨质疏松症患者的治疗。