Factors Influencing Engraftment in Submyeloablated Hosts

影响深髓清除宿主植入的因素

基本信息

批准号：
7476302
负责人：
William Scott Goebel
金额：
$ 13.34万
依托单位：
INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-08-02 至 2010-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7476302
关键词：
Antimetabolites Autologous Award Biology Blood Cells Cell Cycle Cell physiology Cells Cellular biology Childhood Clinical Condition Cultured Cells Data Defect Depth Disease Engraftment Foundations Future Gene Transfer Gene Transfer Techniques Genes Hematological Disease Hematopoiesis Hematopoietic Hematopoietic Stem Cell Transplantation Hematopoietic stem cells Human Human Genetics Intervention Investigation Laboratories Learning Lentivirus Vector Low Dose Radiation Marrow Mediating Mentors Methods Modeling Molecular Mus Nature Non-Malignant Outcome Patients Population Procedures Process Protocols documentation Reporting Research Research Personnel Resource Sharing Resources SCID Mice Technical Expertise Techniques Testing Toxic effect Training Transplantation Treatment Protocols Xeno base cellular transduction clinically relevant conditioning gene correction gene therapy improved in vivo interest mouse model novel programs research study self-renewal

项目摘要

DESCRIPTION (provided by applicant): Gene therapy, combined with autologous hematopoietic stem cell (HSC) transplantation, has the potential to treat a variety of nonmalignant, congenital hematologic disorders. Gene transfer to HSC followed by transplantation of those HSC into fully myeloablated subjects can produce high levels of gene-corrected blood cells in vivo. Unfortunately, intensive conditioning regimens are associated with significant toxicity. As a result, submyeloablative conditioning has been proposed as an alternative transplantation method. Transplantation of transduced HSC into submyeloablated syngeneic hosts, however, is less efficient than transplantation of transduced HSC into fully ablated hosts. This laboratory recently observed that marrow cells cultured ex vivo during gene transfer acquire an engraftment defect that is evident in submyeloablated hosts. Because most transduction protocols involve ex vivo culture, this engraftment defect is likely to impede efforts to achieve clinically relevant levels of gene-corrected blood cells in the submyeloablative setting. The current understanding of the mechanisms governing HSC self-renewal and how these processes are altered during ex vivo culture are incomplete; a better understanding of both are necessary for improved clinical outcomes. The experiments proposed in this application will determine factors important for the engraftment of transduced HSC in two models of submyeloablative conditioning for murine hosts, low dose radiation and a novel antimetabolite-based regimen. We hypothesize that the manipulations required for HSC transduction produce changes in HSC function that negatively impact engraftment in submyeloablated hosts. We plan to test this hypothesis, in murine syngeneic and xenogeneic human-NOD/SCID mouse models, using the following specific aims: 1) Determine the extent to which ex vivo transduction of HSC under optimized conditions improves engraftment in submyeloablated hosts; 2) Determine the molecular mechanism by which ex vivo transduction impairs HSC engraftment in submyeloablated hosts; and 3) Determine the capacity of non-HSC populations present in the marrow to enhance long-term engraftment of transduced HSC in submyeloablated hosts. The findings from these studies, together with the technical expertise and scientific direction acquired from further mentored training during this award period, will form the foundation for future independent investigations into mechanisms responsible for maintaining human HSC self-renewal and engraftment in the setting of hematopoietic cell gene therapy.

描述（由申请人提供）：基因疗法与自体造血干细胞（HSC）移植相结合，有可能治疗多种非恶性先天性血液疾病。将基因转移到 HSC，然后将这些 HSC 移植到完全清髓的受试者体内，可以在体内产生高水平的基因校正血细胞。不幸的是，强化调理方案与显着的毒性相关。因此，清髓性预处理被提议作为替代移植方法。然而，将转导的HSC移植到髓部亚清除的同系宿主中的效率低于将转导的HSC移植到完全消融的宿主中的效率。该实验室最近观察到，在基因转移过程中离体培养的骨髓细胞出现了移植缺陷，这在清髓性宿主中很明显。由于大多数转导方案涉及离体培养，因此这种植入缺陷可能会阻碍在清髓环境下实现临床相关基因校正血细胞水平的努力。目前对 HSC 自我更新机制以及这些过程在离体培养过程中如何改变的理解还不完整；更好地了解两者对于改善临床结果是必要的。本申请中提出的实验将确定对于小鼠宿主的两种清髓性调理模型、低剂量辐射和基于新型抗代谢物的方案中转导的 HSC 植入的重要因素。我们假设 HSC 转导所需的操作会导致 HSC 功能发生变化，从而对亚清髓宿主中的植入产生负面影响。我们计划在小鼠同系和异种人类 NOD/SCID 小鼠模型中检验这一假设，具体目标如下： 1) 确定在优化条件下 HSC 的离体转导在多大程度上改善了清髓性宿主中的植入； 2) 确定离体转导损害HSC在清髓性宿主中植入的分子机制； 3) 确定骨髓中存在的非 HSC 群体增强转导的 HSC 在清髓性宿主中长期植入的能力。这些研究的结果，加上在此奖励期间通过进一步指导培训获得的技术专业知识和科学方向，将为未来对造血细胞中负责维持人类 HSC 自我更新和植入的机制进行独立研究奠定基础。基因疗法。