Wnt signaling in hematopoietic development

项目概要/摘要： 造血干细胞（HSCs）在血液中产生所有终末分化细胞。HSC的能力 重建这些血细胞谱系的生命是骨髓移植治疗的功效的基础， 治疗各种血液疾病，包括白血病、贫血和自身免疫。虽然这是一个 在现有的有效治疗方法中，三分之二需要移植的患者缺乏匹配的供体。 因此，治疗性HSC的替代来源将是该领域的布恩。人多能干细胞 人PSC（hPSC）代表了基于细胞的疗法的潜在来源，包括患者特异性造血干细胞的衍生。 可移植的造血干细胞，这将另外规避免疫排斥和同种异体反应，这两个主要问题， 在诊所里 拟议的合作研究利用了两位主要研究者的专业知识， 在干细胞生物学、斑马鱼遗传学和发育、鼠HSC生物学方面的研究兴趣和技能， 造血发育以及Wnt生物学和生物化学。使用斑马鱼和hPSC作为模型系统， 他们试图识别和表征在早期造血发育过程中指导造血发育的分子线索， 胚胎阶段，强调Wnt信号的作用。拟议的研究将以他们的发现为基础 由Wnt 9a/Frizzled 9/EGFR调节的信号传导轴是HSC出现所特别需要的， 扩展到脊椎动物门。该提案将利用斑马鱼和体外谱系追踪方法 hPSC的分化方案结合单细胞测序方法来确定分子 这一要求的机制，并提供一个新的水平了解后外侧中胚层如何 被指示生成HSC。 这些研究的长期目标是更好地了解HSC在胚胎中的发育， 以便将这些信息转化为hPSC。这项研究的成功完成将产生深远的影响 对HSC的衍生和扩展，从而将有助于克服目前的障碍， 有效治疗需要骨髓移植治疗的疾病。

Project Summary/Abstract: Hematopoietic stem cells (HSCs) give rise to all terminally differentiated cells in the blood. The ability of HSCs to reconstitute these blood cell lineages for life underlies the efficacy of bone marrow transplantation therapy for treatment of various blood disorders, including leukemias, anemia, and autoimmunity. Although this is an established and effective treatment, two-thirds of patients in need of a transplant lack a matched donor. Therefore, alternative sources of therapeutic HSCs would be a boon to the field. Human pluripotent stem cells (hPSCs) represent a potential source for cell-based therapies, including the derivation of patient-specific transplantable HSCs, which would additionally circumvent immune rejection and alloreactivity, both major issues in the clinic. The proposed collaborative research leverages the expertise of two Principal Investigators with complementary research interests and skills in stem cell biology, zebrafish genetics and development, murine HSC biology, hematopoietic development, and Wnt biology and biochemistry. Using zebrafish and hPSCs as model systems, they seek to identify and characterize the molecular cues that direct hematopoietic development during early embryonic stages, with an emphasis on the role of Wnt signaling. The proposed studies will build on their finding that a signaling axis regulated by Wnt9a/Frizzled9/EGFR is specifically required for HSC emergence and expansion across vertebrate phyla. This proposal will leverage lineage tracing methods in zebrafish and in vitro differentiation protocols of hPSCs combined with single-cell sequencing approaches to determine the molecular mechanisms of this requirement, and to provide a new level of understanding of how posterior lateral mesoderm is instructed to generate HSCs. The long-term goal of these studies is to gain a better understanding of how HSCs develop in the embryo in order to translate this information to hPSCs. Successful completion of this research will have a profound impact on HSC derivation and expansion, and thereby will be instrumental in overcoming current obstacles to the effective treatment of diseases requiring bone marrow transplant therapy.