Regional Gene Therapy to Enhance Bone Repair

描述(来自申请者的逐字描述)：区域基因治疗是一项新的 增强人类骨骼修复的方法。有人担心，单一的 接触外源重组蛋白可能不会产生令人满意的 骨诱导刺激对有明显骨丢失的患者。在以前的 工作，我们已经证明了体外基因转移策略的有效性 用腺病毒基因产生BMP-2的大鼠骨髓细胞 调职。这些细胞被用来修复一个临界大小的股骨缺损。 老鼠。我们现在的目标是进一步探索区域性基因治疗的潜力。 这样我们就可以更好地将这项技术应用于人类。该计划是为了加强我们的 利用体外基因对骨修复过程生物学的认识 通过评估体内BMP产生的持续时间和定位BMP转移 随着时间的推移，骨形态发生蛋白在缺损处的分泌。此外，该组织的作用 转导的骨髓细胞和宿主细胞将在骨修复过程中 确定，评估对基因治疗的免疫反应和 腺病毒存在于不同的解剖部位。这项研究建议在 特殊目标1将评估另一种细胞类型(皮肤成纤维细胞)作为 潜在的细胞输送载体，用于修复临界大小的骨缺损。这个 在特定目标2中提出的研究将调查EX的疗效 活体腺病毒基因转移更严格和临床相关 试图修复成人(12个月大)和老年人(18岁)股骨缺损的模型 一个月大的)老鼠。在具体目标1和2中，BMP生产的持续时间 在体内，骨形态发生蛋白在缺损处的定位将被评估。在……里面 特定目标3，产生BMP-2的骨髓细胞在骨骼中的作用 修复过程和供体细胞将在小鼠模型中进行评估。在……里面 具体目标4，我们将：(A)比较体外基因转移的效果 用产生BMP-2的骨髓细胞和直接体内注射 病毒；及(B)比较这两种基因疗法的安全性和毒性 战略。这项拟议的研究将增进我们对以下方面的了解 基因治疗在促进骨修复方面的潜在陷阱，希望 让我们更进一步地将这项技术应用于人类。

DESCRIPTION (Verbatim from the Applicant): Regional gene therapy is a novel approach to enhance bone repair in humans. There is concern that a single exposure to exogenous recombinant protein may not induce a satisfactory osteoinductive stimulus in patients with significant bone loss. In previous work, we have demonstrated the efficacy of an ex vivo gene transfer strategy using BMP-2-producing rat bone marrow cells created via adenoviral gene transfer. These cells were used to heal a critical-sized femoral defect in rats. Our goal now is to further explore the potential of regional gene therapy so we can better adapt this technology for humans. The plan is to enhance our understanding of the biology of the bone repair process with ex vivo gene transfer by assessing the duration of BMP production in vivo and localizing the BMP secretion in the defect site over time. In addition, the role of the transduced bone marrow cells and host cells in the bone repair process will be determined, evaluating both the immune response to gene therapy and the presence of adenovirus at various anatomic sites. The research proposed in Specific Aim 1 will evaluate another cell type (skin fibroblasts) as a potential cellular delivery vehicle to heal critical-sized bone defects. The research proposed in Specific Aim 2 will investigate the efficacy of the ex vivo adenoviral gene transfer in a more stringent and clinically relevant model by trying to heal femoral defects in adult (12 month old) and elderly (18 month old) rats. In both Specific Aims 1 and 2, the duration of BMP production in vivo and the localization of BMP in the defect will be assessed. In Specific Aim 3, the role of the BMP-2-producing bone marrow cells in the bone repair process and the donor cells will be assessed in a mouse model. In Specific Aim 4, we will: (a) compare the efficacy of the ex vivo gene transfer strategy with BMP-2-producing bone marrow cells and direct in vivo injection of the virus; and (b) compare the safety and toxicity of these two gene therapy strategies. This proposed research will enhance our knowledge with respect to the potential pitfalls of gene therapy in enhancing bone repair and hopefully take us a step closer to adapting this technology for use in humans.