OSTEOBLASTIC STEM CELLS AS GENE THERAPY

描述（改编自申请人的摘要）：兴趣正在建立 考虑体细胞基因治疗作为一种方法，遗传性疾病的 成骨细胞如成骨细胞（OI）。 重大问题， 可能是骨骼和其他结缔组织细胞所特有的严重需要 在制定一个有说服力的战略之前，必须进行审议。 具体 需要确定是否有骨干细胞， 其将产生分化成骨细胞的祖细胞库 表达纠正基因。 将提出五个基本问题， 本申请利用携带标记基因的转基因供体小鼠， 可以指示来源于细胞的来源和分化状态， 一个操纵的干细胞：（1）更新成骨细胞自然产生于 循环干细胞，组织驻留干细胞，或两者兼而有之？(2)是什么 骨强度明显正常的分子和细胞基础， 体细胞嵌合体突变导致OI的患者？ 用于干细胞 要想治疗成功，工程细胞需要进入一个天然池， 循环细胞的数量来填充OI骨， 细胞和改善疾病的严重程度。 这些问题将得到回答， 来自携带不同转基因的胚胎供体的异基因小鼠;（3） 即使干细胞不能正常循环， 填充骨骼并产生分化的成骨细胞？ MSC将在 并用于骨形成的异位和髓内测定 和干细胞数量。 用TK基因改造的小鼠，由 COL 1A 1启动子将用于评估移植MSC的能力， 移植骨并参与骨形成;（4）和（5）MSC可以 用逆转录病毒载体操纵，所述逆转录病毒载体含有普遍存在的或 COL 1A 1启动子并仍保持其归巢和造骨的能力？ 这个项目代表了三个主要研究者的融合， 不同的，但相互作用的学科的复杂问题， MSC作为细胞成分在整体策略中的可行性 骨的体细胞基因治疗

DESCRIPTION (Adapted from the Applicant's Abstract): Interest is building to consider somatic gene therapy as an approach to heritable diseases of the osteoblast such as osteogenesis imperfecta (OI). Significant problems which may be unique to bone and other connective tissue cells need serious consideration before a cogent strategy can be formulated. Specifically, it needs to be determined whether there is a bone stem cell that can be targeted which will yield a progenitor pool of differentiated osteoblasts expressing the correcting gene. Five fundamental questions will be asked by this application, utilizing transgenic donor mice bearing marker genes which can indicate the source and the differentiation state of cells derived from a manipulated stem cell: (1) do renewing osteoblasts naturally arise from a circulating stem cell, a tissue resident stem cell, or both?; (2) what is the molecular and cellular basis of apparently normal bone strength in patients who are somatic mosaics for a mutation causing OI? For stem cell therapy to be successful, engineered cells will need to enter a natural pool of circulating cells to populate OI bone, replace the function of the OI cells and ameliorate disease severity. These issues will be answered with allophenic mice derived from embryo donors bearing different transgenes; (3) even if stem cells do not normally circulate, can stem cells be made to populate bone and yield differentiated osteoblasts? MSC will be expanded in vitro and used in a heterotopic and intramedullary assay of bone formation and stem cell number. A mouse engineered with the TK gene, controlled by the COL1A1 promoter, will be used to assess the ability of transplanted MSC to engraft bone and participate in bone formation; (4) and (5) can MSC be manipulated with retroviral vectors containing either ubiquitous, or a COL1A1 promoter and still maintain its ability to home to, and make bone? This project represents a fusion of three principal investigators, bringing different, but interacting disciplines to the complex question of feasibility of MSCs as the cellular ingredient in an overall strategy of somatic gene therapy of bone.