BOEC in Biology

描述(申请人提供)：我们的初步数据表明，分子工程的BOEC(血液生长内皮细胞)可以用于血友病A的有效基因治疗。本项目将研究BOEC生物学的几个方面，这些方面与BOEC的这一潜在治疗用途直接相关。三个特定的目标将利用给予NOD的人类BOEC模型(要么是未经操纵的，要么是表达人类第VIII因子的)。SCID小鼠。在目标1中，我们将确定BOEC的骨髓“归位”行为。我们将确定BOEC在静脉注射时的短期和长期去向。我们将确定BOEC植入骨髓和脾的机制。我们将确定BOEC的骨髓/脾种植是否可以从药理上增加(组胺，或β-1-整合素激活抗体，或VEGF，或1L6加干细胞因子)。我们将确定BOEC在骨髓中明显较低的播种频率是否是建立BOEC移植物的随机或预编程特征。在目标2中，我们将研究有关BOEC体内移植物扩张和寿命的某些问题。我们将证实我们的初步印象，即BOEC在静脉注射后在体内显著扩张。我们将确定这种体内扩张是否是可预测的，并取决于BOEC先前的传代历史。我们将努力确认我们的fVIlI转基因表达载体在BOEC中不存在沉默问题。在目标3中，我们期望证明静脉注射BOEC后体内内皮细胞的扩张是由于真正的BOEC细胞而不是污染的造血祖细胞。这些研究中的每一项都解决了在BOEC技术应用于治疗之前必须了解的一个问题。除了最终的治疗方法外，这些研究还将定义这种独特细胞类型的各个方面。

DESCRIPTION (provided by applicant): Our preliminary data indicate that molecularly engineered BOEC (blood outgrowth endothelial cells) can be used for effective gene therapy of hemophilia A. The present project will examine several aspects of BOEC biology that are directly relevant to this potential therapeutic use of BOEC. Three Specific Aims will utilize the model of human BOEC (either unmanipulated or engineered to express human factor VIII) given to NOD. SCID mice. In Aim 1 we will identify the marrow "homing" behavior of BOEC. We will determine where BOEC go in the short- and long-terms when given intravenously. We will identify mechanisms underlying BOEC seeding of marrow and spleen. We will determine if BOEC seeding of marrow/spleen can be increase pharmacologically (with histamine, or beta-1-integrin activating antibody, or VEGF, or 1L6 plus stem cell factor). We will determine if the apparently low seeding frequency of BOEC in marrow is a stochastic or pre-programmed characteristic of establishing a BOEC graft. In Aim 2 we will examine certain issues regarding BOEC graft expansion and longevity in vivo. We will confirm our preliminary impression that BOEC expand substantially in vivo after being administered intravenously. We will determine if this in vivo expansion is predicatble and is dependent on the prior passaging history of the BOEC. We will seek to confirm that silencing of our fVIlI transgene expression vector is not a problem in BOEC. in Aim 3 we expect to document that endothelial expansion in vivo after intravenous administration of BOEC is due to a true BOEC cell rather than a contaminating hematopoietic precursor cell. Each of these studies addresses an issue that is necessary to understand before BOEC technology can be applied for therapeutics. Aside from eventual therapeutics, these studies will define aspects of this unique cell type.