High resolution lineage tracing of developmental hematopoiesis

项目概要/摘要： 研究细胞类型的起源是理解发育生物学基本过程的关键， 能够在体外产生有益于治疗的细胞和组织。虽然我们对人类行为的理解 尽管已经完成了造血细胞的个体发生，但重大的技术限制使我们无法 具有发育过程中血细胞谱系关系的全貌。例如，普遍的 该领域的观点是，胚胎中出现的造血干细胞（HSC）是负责 哺乳动物一生的血液生产。然而，有限的数据存在，分析长期的命运， 造血祖细胞完全在原位。此外，该领域仍然缺乏对真正的 在成人中将成为终身HSC/祖细胞的细胞的解剖学起源部位。卡马戈 和霍莫兹实验室率先使用原位哺乳动物条形码策略来进行谱系 在单个细胞水平上追踪。我们在这里的建议旨在利用这些系统调查发展 造血的起源我们的申请是基于我们对不可移植的 胚胎多能祖细胞（eMPPs），长期促进出生后造血。 这些发现意味着，除了传统的HSC外，祖细胞群具有活性和实质性的造血干细胞。 对成人多系造血的贡献。我们在这个应用程序中的第一个目标是进一步表征 eMPPs的分子和功能。我们还将探讨造血功能的差异 谱系可以基于它们的eMPP或HSC个体发生而产生。最后，我们将扩展条形码的使用范围 广泛和无偏见地描述血液产生的发育波及其确切特征的方法 原产地。我们的工作有可能揭示血液发育的基本机制， 用于治疗操作。

Project Summary/Abstract: Investigating the origin of cell types is key to understanding basic processes in developmental biology and to enable in vitro production of cells and tissues for therapeutic benefit. While major advances in our understanding the ontogeny of hematopoietic cells have been made, significant technical limitations have precluded us from having a full picture of the lineage relationships of blood cells during development. For instance, the prevailing view in the field is that hematopoietic stem cells (HSCs) that emerge in the embryo are the cells responsible for lifelong blood production in the mammal. However, limited data exist that analyse the long-term fate of the earliest hematopoietic progenitors entirely in situ. Furthermore, the field still lacks a conclusive understanding of the true anatomical site of origin of the cells that will become the lifelong HSCs/progenitors in the adult. The Camargo and Hormoz laboratories have pioneered the use of in situ mammalian barcoding strategies to perform lineage tracing at the single cell level. Our proposal here aims to utilize these systems investigate the developmental origins of hematopoiesis. Our application is based on our identification of a population of non-transplantable embryonic multipotent progenitors (eMPPs) that contribute long-term to post-natal hematopoiesis. These findings imply that progenitor populations in addition to traditional HSCs have an active and substantial contribution to adult multilineage blood production. Our first goal in this application is to further characterize eMPPs molecularly and functionally. We will also explore the idea that functional differences in hematopoietic lineages can arise based on their eMPP or HSC ontogeny. Finally, we will extend the use of our barcoding approaches to broadly and unbiasedly characterize developmental waves of blood production and their exact site of origin. Our work has the potential to uncover basic mechanisms of blood development that could be useful for therapeutic manipulation.