AAV vectors expressing angiogenic factors for CHD

肌肉注射AAV载体是运送促红细胞生成素和因子IX等分泌蛋白的有效途径。因此，该载体似乎可用于运送血管生成因子用于治疗冠心病。初步实验表明，这种管理模式确实可能是有用的。在冠状动脉结扎和非冠状动脉结扎的小鼠中，比较了AAV载体通过心内注射进入心肌的血管内皮生长因子。在冠状动脉结扎的小鼠中，可以看到新生血管的形成，而在冠状动脉完整的小鼠中，几乎看不到血管。(1)这个项目的第一个目标是将这些研究扩大到更多的动物。由于与冠状动脉结扎相关的病理生理变化在大鼠身上建立得更好，因此这些研究将在大鼠身上进行。动物将接受电生理学和超声心动图检查，然后处死动物进行病理和血管形成的组织学检查。此外，还将使用一种新的心脏血管三维成像方法。(2)本项目的第二个目标是研究调控血管生成因子在心肌中表达的方法。已有研究表明，心肌组织中高水平表达的血管内皮生长因子可导致血管瘤的形成，因此控制血管生成因子的表达具有重要意义。第一种可能导致血管瘤的形成，重要的是控制血管生成因子的表达。我们将研究的第一种调节模式是使用促红细胞生成素基因中的低氧反应元件。初步数据显示，这种元件的几个拷贝串联排列可以增加基因的表达，以应对缺氧。将测试其他可诱导的启动子，如四环素或黄体酮受体系统。(3)第三个目标是提高新血管形成的质量和数量。血管生成素和成纤维细胞生长因子，单独和联合血管内皮生长因子将被研究。

Intramuscular injection of AAV vectors is an efficient way of delivering secretory proteins such as erythropoietin and Factor IX. It appears, therefore, that this vector could be useful for delivering angiogenic factors for the treatment of coronary heart disease. Preliminary experiments indicate that this model of administration may indeed by useful. VEGF delivered by AAV vectors into the myocardium by intracardiac injection was compared in mice with or without coronary artery ligation. In mice with ligated coronary arteries, ne blood vessel formation was seen, whereas in the mice with intact coronary, very few blood vessels were seen. (1) The first aim of this project is to extend these studies to a larger number of animals. Because the pathophysiological changes associated with ligation of the coronary artery are much better established in rats, these studies will be performed on rats. The animals will be examined by electrophysiology and echocardiography before they are sacrificed for histological examination for pathology and blood vessel formation. Also, a new method for three dimensional imaging of cardiac blood vessels will be used. (2) A second aim of this project is to investigate methods of regulating angiogenic factors of expression in the myocardium. As it has been shown that high level of expression of VEGF in the myocardium may result in hemangioma formation, it is important to control the expression of angiogenic factors. The first may result in hemangioma formation, it is important to control the expression of angiogenic factors. The first mode of regulation that we will investigate that we will investigate is to use the hypoxia responsive element from the erythropoietin gene. Preliminary data showed several copies of this element arranged in tandem could increase the expression of genes in response to anoxia. Other inducible promoters such as the tetracycline or the progesterone receptor system will be tested. (3) A third aim is to improve the quality and quantity of new blood vessel formation. The angiopoietin and fibroblast growth factor, alone and in combination with VEGF will be investigated.