PREVENTION OF THROMBOSIS IN ANGIOPLASTY INJURED ARTERIES

描述(改编自申请人的摘要)：内皮是 具有几种生物活性分子来保护血管 保持完整，保持血管止血。前列环素(PGI2)是 重要的血管保护分子。它能抑制血小板 激活和聚集，抑制平滑肌细胞的激活和聚集 迁移，并抑制单核细胞的激活。它还会减少 血管收缩反应。局部PGI2合成减少，原因是 内皮损伤可能导致过多的血液和血管细胞 激活，从而加速血栓形成和新生内膜的增殖。 全身给予PGI2以增加局部PGI2浓度 由于不良的不利影响，有限的成功。申请人 建议测试在受损的血管中是否局部产生PGI2 可通过基因转移PGI2合成酶和 增强局部PGI2的合成可以预防血管血栓形成。 花生四烯酸(AA)生物合成前列腺素I2的催化作用 前列腺素H合成酶(PGHS，又称环氧合酶) 将AA转换为PGG2，然后将PGG2转换为PGH2。PGH2进一步转化为 通过前列环素合成酶(PGIS)转导至PGI2。在初步研究中，这一点 研究小组已经表明，内皮细胞PGHS-1水平通过 逆转录病毒和腺病毒介导的人PGHS-1基因的转移 伴随着PGI2合成的大幅增加。管理 腺病毒-CMV-PGHS-1进入血管成形术损伤的猪颈动脉 导致PGI2合成增加5倍。为了进一步发展 关于血管基因转移的研究，提出了5个具体目标： 1)评价腺病毒载体介导的前列腺素H的作用 合酶-1(PGHS-1)基因转移预防实验性血栓形成 动物模型；2)评价血管内皮细胞转移的效果 前列环素合成酶(PGIS)单独及与PGHS-1基因的联合作用 培养内皮细胞产生前列腺素I2的程度和持续时间 体外细胞培养和体内血栓形成的预防；3)测定 PGHS-1和/或PGIS基因转移对血管内膜增生的影响 实验动物模型；4)评估非病毒载体 转移PGHS-1和/或PGIS cDNAs促进植物体内PGI2合成 血管保护；5)使用上述基因中最有效的 治疗和确定其预防血栓形成和治疗的有效性 动脉粥样硬化性猪冠状动脉内膜增殖。

DESCRIPTION (adapted from the applicant's abstract): Endothelium is endowed with several biologically active molecules to protect vascular integrity and maintain vascular hemostasis. Prostacyclin (PGI2) is one of the important vasoprotective molecules. It inhibits platelet activation and aggregation, suppresses smooth muscle cell activation and migration, and inhibits monocyte activation. It also diminishes vasoconstrictor responses. Reduced local PGI2 synthesis due to endothelial injury may lead to excessive blood and vascular cell activation thereby accelerating thrombosis and neointimal proliferation. Systemic administration of PGI2 to augment local PGI2 concentration has limited success because of undesirable adverse effects. The applicant proposes to test whether local production of PGI2 at a damaged vascular site can be restored by gene transfer of PGI2 synthetic enzymes and the augmented local PGI2 synthesis can protect against vascular thrombosis. Biosynthesis of PGI2 from arachidonic acid (AA) is catalyzed by prostaglandin H synthase (PGHS, also called cyclooxygenase) which converts AA into PGG2 and than PGG2 to PGH2. PGH2 is further converted to PGI2 by prostacyclin synthase (PGIS). In preliminary studies, this group has shown that endothelial cell PGHS-1 levels are augmented by retrovirus- and adenovirus-mediated transfer of human PGHS-1 cDNA which is accompanied by a large increase in PGI2 synthesis. Administration of adenovirus-CMV-PGHS-1 into angioplasty-damaged pig carotid arteries resulted in a 5-fold increase in PGI2 synthesis. To further the investigation of vascular gene transfer, 5 specific aims are proposed: 1) to evaluate the effect of adenovirus-mediated prostaglandin H synthase-1 (PGHS-1) transfer on preventing thrombosis in experimental animal models; 2) to assess the effect of transfer of endothelial prostacyclin synthase (PGIS) alone and in combination with PGHS-1 gene on the extent and duration of PGI2 production in cultures endothelial cells in vitro and on preventing thrombosis in vivo; 3) to determine the effect of PGHS-1 and/or PGIS gene transfer on intimal hyperplasia in experimental animal models; 4) to evaluate non-viral vectors for transferring PGHS-1 and/or PGIS cDNAs for augmenting PGI2 synthesis in vasoprotection; and 5) to use the most effective of the above gene therapies and determine its efficacy in preventing thrombosis and intimal proliferation in atherosclerotic porcine coronary arteries.