Strategies to promote Engraftment of Genetically Modified Hemopoietic

项目后续 某种形式的骨髓抑制对于移植的遗传校正的自体干细胞的有效和持久植入是必要的。支持有效植入但不使患者遭受过度毒性和风险的温和调节方案是非常期望的，但这些方案尚未在大型动物或人类中进行测试。在这个项目中，我们也提出了在小鼠和灵长类动物临床前模型中研究两种这样的创新调理方案。所提出的实验测试的假设，即低剂量照射与抗体介导的干细胞功能的损害或与使用干细胞动员剂的组合将促进遗传校正的干细胞的植入。因此，低剂量辐照将在特定目标1中与抗人c-kit治疗组合以减少干细胞/祖细胞库，并在特定目标2中与动员剂组合以置换干细胞/祖细胞。辅助 将在小鼠中进行使用类似方案的初步实验，以提供指导和机制线索。由于不仅受体调理是增强植入所必需的，因此供体细胞的创新治疗也很重要。我们将在具体目标3中讨论这个问题。为了增强植入，在这个特定的目的中，我们利用短期处理体外孵育的鼠或人源细胞与dmPGE 2和它们的移植在免疫缺陷宿主（NOD/SCID）。将在相同的免疫缺陷受体模型中进行用dmPGE 2离体wVo处理的鼠细胞与人细胞的行为比较，也允许机制问题的方法。我们相信，这些实验的结果将有重要的临床意义，在人类移植的结果，使用自体基因校正的细胞。

PROJECT SUIVIMARY Some form of myelosuppression is necessary for effective and durable engraftment of transplanted genetically corrected autologous stem cells. Milder conditioning protocols which support efficient engraftment but do not subject patients to undue toxicity and risks are highly desirable, but these have not been tested in large animals or humans as yet. In this project we propose too investigate two such innovative conditioning regimens in murine and primate preclinical models. The proposed experiments test the hypothesis that low dose irradiation in combination with either Ab-mediated impairment of stem cell function or with the use of stem cell mobilizing agents will facilitate the engraftment of genetically corrected stem cells. Thus, low dose irradiation will be combined in Specific Aim 1 with anti-human c-kit treatment to reduce the stem/cell progenitor pool and in Specific Aim 2 with a mobilizing agent for displacement of stem/progenitor cells. Ancillary preliminary experiments using similar regimens will be conducted in mice to provide guidance and mechanistic clues. Since not only recipient conditioning is necessary for enhanced engraftment, innovative treatments of donor cells are also important. We will address this issue in Specific Aim 3. To enhance engraftment, in this Specific Aim we exploit short term treatment of in vitro incubated cells of murine or human origin with dmPGE2 and their transplantation in an immunodeticient host (NOD/SCID). Comparison of the behavior of murine vs. human cells treated ex wVo with dmPGE2 will be done in the same immunodeficient recipient model allowing also the approach of mechanistic issues. We believe that results from these experiments will have important clinical implications in transplantation outcomes in humans using autologous gene corrected cells.