Regulation of hemangiogenesis by adenoviral E4 genes

腺病毒E4基因调控血管生成

• 批准号: 6670766
• 负责人: Shahin Rafii
• 金额: $ 29.04万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6670766
• 关键词: Adenoviridae; NOD mouse; SCID mouse; angiogenesis; athymic mouse; cell proliferation; hematopoietic stem cells; human tissue; inflammation; open reading frames; transfection /expression vector; vascular endothelial growth factors; vascular endothelium; virus genetics

DESCRIPTION (provided by applicant): Endothelial and hematopoietic cells are ideal targets for gene therapy because are readily accessible to gene therapy vectors via the circulation and play a critical role in the progression of disease processes including inflammation and tumor angiogenesis. Adenoviral (Ad) vectors which could infect quiescent vascular cells provide ideal vectors to introduce genes into vascular endothelium as well as hematopoietic stem and progenitor cells with high efficiency and low toxicity. However, expression of genes by Ad vectors has been hampered by infiltration of inflammatory cells and intravascular activation of neo-intimal cells. Despite numerous studies defining the role of immune response to Ad vectors the exact mechanism whereby Ad vectors modulate activation status of ECs and hematopoietic cells and subsequent inflammatory response is not know. We have shown that introduction of E1-E4+, but not E1-E4-Ad vectors into primary ECs results in profound alteration in the proliferation and inflammatory status of the ECs. Infection of ECs with E4+ Ad vectors result in the generation of unique state where ECs do not proliferate or undergo apoptosis. This state is also associated with the upregulation of inflammatory adhesion molecules including ICAM, VCAM, and CD34. Moreover, E4 mediated activation of ECs enhance transendothelial migration of hematopoietic precursor cells and proinflammatory cells. These data clearly demonstrate that one or a combination of E4 gene products encoded by seven distinct E4 open reading frames (ORFs) regions may play a critical role in modulation of angiogenic and inflammatory potential of ECs. Based on these data, we hypothesize that gene products encoded by the E4 region of Ad vectors pirate the molecular machinery of ECs resulting in transformation of ECs into a unique pro-angiogenic and proinflammatory state. Identification of E4ORF genes that modulate angiogenic and inflammatory potential of ECs hematopoietic cells will facilitate designing strategies to attenuate vascular toxicity associated with Ad vector gene therapy. The mechanism by which E4ORFs gene products modulate angiogenic and inflammatory potential will be investigated through studying the following experiments: 1) Identifying specific E4ORF genes that alone or in combination modulate angiogenic and inflammatory potential of ECs in in vitro and in vivo models. 2) Assess the effect of E4ORFs gene products in the modulation of angiogenic potential of circulating VEGFR2+AC133+endothelial precursor cells (EPCs) and hematopoietic stem and progenitor cells. 3) Define the mechanism(s) whereby E4ORFs modulate the motility and mitogenic potential of ECs and hematopoietic progenitor and stem cells. 4) Define the role of E4ORFs in physiological models of angiogenesis and inflammation. These experiments may culminate in identification of E4ORFs that promote or inhibit angiogenesis, and diminish E4 mediated vascular toxicity. Incorporation of pro-angiogenic E4ORFs in conjunction with transgenes expressing VEGF, will facilitate developing clinical strategies to enhance collateral formation in ischemic myocardium or limbs. Conversely, E4ORFs with anti-angiogeni properties may be used in clinical strategies that are targeted at inhibiting tumor angiogenesis or blocking aberrant angiogenesis in clinical scenarios, such as diabetic retinopathy.

描述（由申请人提供）： 内皮细胞和造血细胞是基因治疗的理想靶标，因为基因治疗载体可以通过循环易于获取，并在包括炎症和肿瘤血管生成在内的疾病过程的进展中起关键作用。可能感染静态血管细胞的腺病毒（AD）载体提供了理想的载体，以高效和低毒性将基因引入血管内皮以及造血干细胞和祖细胞。然而，AD载体对基因的表达受到炎症细胞的浸润和新触觉细胞的血管内激活的阻碍。尽管许多研究定义了免疫反应对AD载体的作用，但AD矢量调节EC和造血细胞的激活状态以及随后的炎症反应的确切机制不知道。我们已经表明，将E1-E4+的引入，而不是将E1-E4-AD向量引入原发性ECS中会导致EC的增殖和炎症状态的深刻改变。 E4+ AD载体的EC感染导致EC不会增殖或凋亡的独特状态产生。该状态还与包括ICAM，VCAM和CD34在内的炎症粘附分子的上调有关。此外，E4介导的EC激活增强了造血前体细胞和 促炎细胞。这些数据清楚地表明，由七个不同的E4开放式阅读框（ORF）区域编码的E4基因产物的一种或组合在调节EC的血管生成和炎症潜力中可能起关键作用。基于这些数据，我们假设由Ad载体的E4区域编码的基因产物海盗的EC分子机制导致ECS转化为独特的促血管生成和促炎状态。 E4orf基因调节ECS造血细胞的血管生成和炎症潜力的E4ORF基因将有助于设计策略，以减轻与AD载体基因治疗相关的血管毒性。 E4ORFS基因产物调节血管生成和炎症潜力的机制将通过研究以下实验进行研究：1）鉴定EC在体外和体内模型中ECS的血管生成和炎症潜力的特定E4ORF基因。 2）评估E4orfs基因产物在循环VEGFR2+AC133+内皮前体细胞（EPCS）以及造血茎和祖发的循环vegfr2+AC133+内皮前体细胞（EPC）调节中的作用 细胞。 3）定义了E4orf调节EC和造血祖细胞和干细胞的运动性和有丝分裂潜力的机制。 4）定义E4orf在生理中的作用 血管生成和炎症的模型。这些实验可能在识别 促进或抑制血管生成并减少E4介导的血管毒性的E4orfs。 将亲血管生成的E4orf与表达VEGF的转基因结合结合，将促进制定临床策略，以增强缺血性心肌或四肢的侧外形成。 相反，具有抗血管疾病特性的E4orf可以用于临床策略中，该策略旨在抑制肿瘤血管生成或阻断临床情况（例如糖尿病性视网膜病）中的异常血管生成。