Cord Blood Expansion/Transplantation Nonhuman Primate

脐带血扩增/移植非人灵长类动物

• 批准号: 7080815
• 负责人: HANS-PETER KIEM
• 金额: $ 71.27万
• 依托单位: FRED HUTCHINSON CANCER RESEARCH CENTER
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2010-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7080815
• 关键词: CD34 molecule; Macaca nemestrina; Retroviridae; T lymphocyte; bone marrow purging; chimeric proteins; clinical research; cord blood; cytokine; fibronectins; gene expression; hematopoietic tissue transplantation; homeobox genes; human tissue; mesenchyme; stem cell transplantation; tissue /cell culture; transcription factor; transfection /expression vector

DESCRIPTION (provided by applicant): The overall goal of this project is to develop novel and improved cord blood expansion strategies and to test in a clinically relevant large animal model whether these strategies can overcome current limitations of cord blood transplantation. Despite some important advantages of cord blood, such as rapid accessibility and a low risk of graft-versus-host disease (GVHD) even in a human leukocyte antigen (HLA) mismatched setting, a major limitation of cord blood transplantation has been the limited number of cord blood cells available, particularly for adult patients. Thus, delayed engraftment and infectious complications have remained significant concerns with cord blood transplantation even with the recently described transplantation of two partially matched cord blood units. Cord blood expansion has been proposed to improve engraftment and hematopoietic reconstitution. However, expansion strategies using cytokines only have so far not resulted in significant improvements in cord blood engraftment in clinical studies. The use of stem cell self-renewal genes has been proposed, and studies in the mouse have shown that overexpression of the transcription factor HOXB4 can result in a dramatic expansion of cord blood and adult stem cells. We have studied the use of HOXB4 for stem cell self-renewal and expansion in a nonhuman primate transplantation model. Using a competitive repopulation assay we directly compared engraftment of marrow-derived CD34+ cells expanded for up to 12 days with and without retrovirally expressed HOXB4. We found that engraftment, in particular short-term engraftment, was significantly higher with HOXB4-transduced / expanded CD34+ cells compared to cells expanded without HOXB4 under otherwise identical conditions. HOXB4 overexpression also resulted in a marked expansion of nonhuman primate cord blood cells. Thus, we propose in the current application to study HOXB4-mediated cord blood expansion and evaluate in a nonhuman primate transplantation model whether this strategy can result in improved engraftment and hematopoietic reconstitution. We propose to 1) optimize HOXB4-mediated cord blood expansion in vitro using retrovirally expressed HOXB4, 2) evaluate improved expansion / transplantation strategies in a nonhuman primate cord blood transplantation model, and 3) determine whether HOXB4-mediated expansion can be achieved with a novel TAT-HOXB4 fusion protein. Studying these strategies in a clinically relevant nonhuman primate model will allow for an efficient evaluation of safety and efficacy and facilitate a rapid translation of our findings to clinical cord blood expansion / transplantation protocols.

描述（由申请人提供）：该项目的总体目标是制定新颖和改进的脐带血扩展策略，并在临床相关的大型动物模型中测试这些策略是否可以克服当前的脐带血移植局限性。尽管脐带血有一些重要的优势，例如快速可及性和移植物抗宿主疾病（GVHD）的风险低，即使在人类白细胞抗原（HLA）不匹配的环境中，索索血液移植的主要限制仍然是脐带血细胞的有限数量，尤其是成人患者。因此，即使最近描述的两个部分匹配的脐带血单位的移植，延迟的植入和感染并发症仍然对脐带血移植仍然存在重大关注。已经提出了脐带血扩大，以改善植入和造血重建。然而，迄今为止，使用细胞因子的扩张策略仅导致临床研究中的脐带血植入术的显着改善。已经提出了干细胞自我更新基因的使用，并且在小鼠中的研究表明，转录因子HOXB4的过表达可能导致脐带血和成年干细胞的急剧扩张。我们研究了HOXB4在非人类灵长类动物移植模型中使用HOXB4进行干细胞自我更新和扩展。使用竞争性的重生测定法，我们直接比较了骨髓来源的CD34+细胞的植入，并在有或没有逆转录病毒表达的HOXB4的情况下扩展了12天。我们发现，与在其他相同条件下没有HOXB4的细胞相比，HOXB4转导 /扩展的CD34+细胞的植入，特别是短期植入的CD34+细胞明显更高。 HOXB4的过表达也导致了非人类灵长类动物脐带血细胞的明显膨胀。因此，我们在当前的应用中建议研究HOXB4介导的脐带血扩张并在非人类灵长类动物移植模型中评估该策略是否可以改善植入和造血重建。我们建议使用逆转录病毒表达的HOXB4，2）在非人类灵长类动物脐带血移植模型中评估改善的扩张 /移植策略，并确定HOXB4介导的扩张是否可以通过新型的Tat-HoxB4 fifusion蛋白质来实现，从而优化HOXB4介导的脐带血扩张，并在非人类灵长类动物的脐带血移植模型中评估改进的扩张 /移植策略。在临床上相关的非人类灵长类动物模型中研究这些策略将有效评估安全性和有效性，并促进我们的发现快速转化为临床脐带血扩张 /移植方案。