Biochemistry of Leukemia Virus Core Binding Factor

描述(申请人提供)：再生医学的一个重要目标是在体外从胚胎或诱导的多能干细胞中制造造血干细胞(HSCs)。目前还没有人实现这一目标。阻碍进展的一个关键因素是我们只部分了解HSC是如何在胚胎中形成和成熟的。拟议的实验的目的是有序地了解胚胎中HSC的形成，并将我们所学到的应用于小鼠和人类胚胎干细胞培养。造血祖细胞和干细胞是从胚胎中的一小部分内皮细胞分化而来的，这些细胞被称为造血源内皮。我们最近发现，大多数血源性内皮细胞都能产生祖细胞，只有少数血源性内皮细胞能产生造血干细胞。可以通过Ly6a驱动的转基因表达来鉴定产生HSC的血源性内皮细胞。在这一应用中，我们提出了评估Ly6a驱动的转基因在优化胚胎干细胞生产HSC方面的效用的实验。表达Ly6a的细胞上调了许多炎症标志物，因此我们将研究炎症在胚胎HSC形成中的作用。最后，我们将检查我们在表达Ly6a的细胞上识别的其他细胞表面标记的实用性。骨髓移植是许多恶性和非恶性血液病患者的救命手段。不幸的是，并不是每个患者都有合适的捐赠者。从患者来源的iPS细胞中培养出造血干细胞的能力将解决这个问题。我们认为，如果我们要成功地在体外生产HSCs，了解HSCs在胚胎中是如何形成的是必要的。

DESCRIPTION (provided by applicant): An important objective in regenerative medicine is to make hematopoietic stem cells (HSCs) from embryonic or induced pluripotent stem cells in vitro. No one has yet achieved this goal. A critical factor hindering progress is that we only partially understand how HSCs form and mature in the conceptus. The purpose of the proposed experiments is to understand HSC formation in the embryo in order, and apply what we learn to mouse and human embryonic stem cell cultures. Hematopoietic progenitor and stem cells differentiate from a small population of endothelial cells in the conceptus called hemogenic endothelium. We recently discovered that most hemogenic endothelium produces progenitors, and only a subset of hemogenic endothelium produces HSCs. The HSC-producing hemogenic endothelium can be identified by expression of a Ly6a-driven transgene. In this application we propose experiments to evaluate the utility of the Ly6a-driven transgene in optimizing HSC production from embryonic stem cells. Ly6a-expressing cells have upregulated many markers of inflammation, thus we will examine the role of inflammation in HSC formation in the embryo. Finally, we will examine the utility of other cell surface markers we have identified on Ly6a-expressing cells. Bone marrow transplantation is a life-saving procedure for many patients with malignant and nonmalignant hematologic disease. Unfortunately not every patient has a suitable donor. The ability to produce HSCs from patient-derived iPS cells would solve this problem. We believe that understanding how HSCs form in the embryo is necessary if we are to successfully produce them in vitro.