Bioengineered, patient-specific bonemarrow model for studying leukemic niche interactions

项目总结/摘要 急性白血病是儿童和年轻人中最常见的癌症（约30%）。的 高风险白血病的实验性治疗的进展受到以下限制： 永生化细胞系以及体内异种移植模型的繁琐性质和有限的通量。在这 在本文中，缺乏用于体外培养原发性白血病样品的稳健系统是研究白血病的重要障碍。 在儿童白血病中开发有效的遗传和化学筛选。体外系统，包括 工程组织和器官芯片系统在干细胞和癌症方面越来越受到关注， 这些领域作为人类特定的平台，用于疾病研究和治疗测试。骨的体外模型 骨髓（BM）尚未获得动力，主要是由于其吞吐量降低，生物技术障碍， 研究，以及起始基质细胞群体的异质性。此外，只有很少的尝试 在工程系统中培养原代供体来源的恶性血细胞， 疾病的研究。在这个拟议的项目中，我将（目标1）设计一个人类诱导多能干细胞（iPSC）- 衍生的骨髓组织模型，由成骨细胞、间充质基质细胞和内皮细胞组成 在骨支架内，用于在体外维持急性淋巴细胞白血病（ALL）表型。然后我将使用 该模型（目的2）研究恶性ALL母细胞的分泌组或ALL母细胞本身如何相互作用 在工程模型中使用健康的造血干细胞和祖细胞（HSPC）以及健康的基质。 我假设一个能够在体外支持HSPC的工程化人类BM微环境， 保持ALL原始细胞的表型比单层培养物或患者更接近未操作样品 衍生的异种移植模型，进一步使研究直接和间接的淋巴母细胞与健康 骨髓已经确定急性白血病改变了它们的微环境生态位， 许多情况下，在治疗过程中使用间质来保护恶性克隆;我假设这个模型系统 将能够更好地预测治疗反应，识别ALL耐药的潜在机制。我们 实验室在人体组织工程、iPSC技术和治疗测试方面拥有强大的专业知识， 在造血、癌症和测序专家的支持下，我相信所提出的项目将成功 建立了一种研究恶性白血病转化过程中人类骨髓的新工具， 对治疗的抵抗

PROJECT SUMMARY / ABSTRACT Acute leukemias represent the most frequent group of cancer (~30%) in children and young adults. The advancement of experimental therapeutics for high risk leukemias has been limited by the inadequacy of immortalized cell lines and the cumbersome nature and limited throughput of in vivo xenograft models. In this context, the lack of robust systems for in vitro culture of primary leukemia samples is a significant barrier for the development of effective genetic and chemical screens in pediatric leukemia. In vitro systems, including engineered tissues and organ-on-a-chip systems, are gaining increased interest in the stem cell and cancer fields as human-specific platforms for the study of disease and therapeutic testing. In vitro models of the bone marrow (BM) have yet to gain momentum, largely due to their reduced throughput, technical barriers in biological research, and the heterogeneity of starting stromal cell populations. Further, there have been only few attempts to culture primary donor-derived malignant blood cells in engineered systems, which enable patient-specific studies of disease. In this proposed project, I will (Aim 1) engineer a human, induced pluripotent stem cell (iPSC)- derived bone marrow tissue model, comprised of osteoblasts, mesenchymal stromal cells, and endothelial cells within a bone scaffold, for maintenance of acute lymphoblastic leukemia (ALL) phenotype in vitro. I will then use this model to (Aim 2) study how the secretome of malignant ALL blasts, or the ALL blasts themselves, interact with both healthy hematopoietic stem and progenitor cells (HSPCs) and healthy stroma in the engineered model. I hypothesize that an engineered human BM microenvironment, capable of supporting HSPCs in vitro, will maintain the phenotype of ALL blasts closer to unmanipulated samples than monolayer cultures or patient derived xenograft models, further enabling studies of direct and indirect lymphoblast interactions with the healthy bone marrow. It has been well established that acute leukemias alter their microenvironmental niche, and in many cases, use the stroma to protect malignant clones during treatment; I hypothesize that this model system will be better able to predict therapeutic responses, identifying potential mechanisms of resistance in ALL. Our lab brings strong expertise in engineering human tissues, iPSC technologies, and therapeutic testing, and with support of experts in hematopoiesis, cancer, and sequencing, I believe that the proposed project will successfully establish a novel tool for studying the human bone marrow during malignant leukemic transformation and resistance to therapy.