Fetal Stem Cell Gene Therapy

胎儿干细胞基因治疗

基本信息

批准号：
6650207
负责人：
MARCUS O MUENCH
金额：
$ 9.02万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
依托单位国家：
美国
项目类别：
财政年份：
2001
资助国家：
美国
起止时间：
2001-09-01 至 2005-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6650207
关键词：
NOD mouse SCID mouse Vesiculovirus cell differentiation cell proliferation embryo /fetus therapy embryonic stem cell erythropoietin gene therapy growth factor receptors hematopoiesis human fetus tissue human immunodeficiency virus 1 murine leukemia virus receptor expression stem cell transplantation technology /technique development transfection /expression vector

项目摘要

DESCRIPTION (adapted from the application) A growing number of hematological diseases can be diagnosed before birth. In some cases, early treatment may benefit the health and survival of the fetus. Either in utero stem cell transplantation (IUT) or fetal gene therapy may treat diseases such as the hemaglobinopathies. This application aims to determine the best method for the introduction of genes into fetal hematopoietic stem cells (HSCs). Fetal HSCs are more proliferative than their adult counterparts and are, therefore, hypothesized to be more susceptible to transduction by retroviral vectors based on murine leukemia virus or human immunodeficiency virus. IUT offers another means of curing a number of hematological diseases by generating a state of hematopoietic chimerism. However, in the absence of any advantage for the donor HSCs, the levels of chimerism that can be achieved by IUT are low. This limits the use of this therapy to very few diseases. Our aim is to extend the use of IUT to the treatment of diseases, such as thalassemia and sickle cell anemia, by engineering HSCs to have a proliferative advantage over normal HSCs. This application will test if introduction of the erythropoietin receptor (EpoR) into HSCs will render these altered cells responsive to erythropoietin (EPO). This will in turn result in the altered HSCs and their progeny having a proliferative advantage over normal progenitors. Truncated forms of EpoR (tEpoR) will also be tested. These tEpoR, having deletions in the negative regulatory region of their cytoplasmic domains, deliver stronger proliferative signals than EpoR. The effects of introducing the EpoR genes on the proliferation and differentiation of HSCs and their progenitor progeny will be determined using various in vitro culture systems. It is hypothesized that ectopic expression of either EpoR or tEpoR will confer the ability of HSCs and early progenitors to proliferate in response to EPO with minimal effect on the differentiation program of these cells. To test if ectopic EpoR or tEpoR expression on HSCs can make these cells more competitive than their normal counterparts, modified HSCs will be tested against control HSCs in a mouse model of human hematopoiesis. The ability of HSCs expressing ectopic EpoR to engraft bone marrow after no or only minimal cytoablation will also be tested. These in vivo experiments will further determine if making HSCs responsive to EPO will have any detrimental effect on the long‑term reconstituting‑ and multilineage‑ potential of HSCs. A positive outcome from the proposed studies would aid in developing treatments for hemoglobinopathies based on generating hematopoietic allochimerism.

描述（改编自应用程序）越来越多的血液疾病可以在出生前得到诊断。在在某些情况下，早期治疗可能有利于胎儿的健康和生存。子宫内干细胞移植（IUT）或胎儿基因治疗都可以治疗疾病，例如血红蛋白病。该应用程序旨在确定将基因导入胎儿造血干细胞的最佳方法（HSC）。胎儿 HSC 比成年 HSC 增殖能力更强，并且因此，推测更容易被转导基于鼠白血病病毒或人类免疫缺陷病毒的逆转录病毒载体病毒。 IUT 提供了另一种治疗多种血液疾病的方法：产生造血嵌合状态。然而，在没有任何供体 HSC 的优势，可以通过以下方式实现的嵌合水平 IUT 较低。这限制了这种疗法仅适用于极少数疾病。我们的目标是将IUT的用途扩展到疾病的治疗，例如地中海贫血和镰状细胞性贫血，通过改造 HSC 使其具有增殖优势超过正常 HSC。该应用程序将测试是否引入促红细胞生成素受体 (EpoR) 进入 HSC 将使这些细胞发生改变对促红细胞生成素（EPO）有反应。这将反过来导致改变造血干细胞及其后代比正常造血干细胞具有增殖优势祖先。还将测试 EpoR 的截短形式 (tEpoR)。这些tEpoR，其细胞质负调控区有缺失域，提供比 EpoR 更强的增殖信号。的影响引入EpoR基因对HSC增殖和分化的影响他们的祖先后代将通过各种体外培养来确定系统。据推测，EpoR 或 tEpoR 的异位表达将赋予 HSC 和早期祖细胞增殖的能力对 EPO 的反应对这些细胞的分化程序影响极小细胞。测试 HSC 上的异位 EpoR 或 tEpoR 表达是否可以使这些细胞改良后的 HSC 比普通 HSC 更具竞争力，将接受测试与人类造血小鼠模型中的对照 HSC 相比。的能力表达异位 EpoR 的 HSC 无需或仅需极少的时间即可植入骨髓细胞消融也将被测试。这些体内实验将进一步确定使 HSC 对 EPO 做出反应是否会对长期重组和多谱系潜力 HSC。拟议研究的积极成果将有助于开发基于生成造血的血红蛋白病治疗异嵌合现象。