Gene therapy for vein graft disease.
ABSTRACT Applying gene therapeutics to vein graft disease requires foundational knowledge of the underlying pathophysiology. This review details a brief description of vein graft disease, examines published and unpublished data on gene transfer to veins, and reviews the genes, which have significantly altered vascular biology.
- SourceAvailable from: Laurent J Feldman[show abstract] [hide abstract]
ABSTRACT: Recombinant adenoviruses are the most efficient vectors with which to perform arterial gene transfer. Previous in vivo studies of adenovirus-mediated arterial transfection, however, have been performed using normal or endothelium-denuded arteries. It is unclear whether these results can be extended to atherosclerotic arteries. Accordingly, this study was designed to (a) assess the feasibility of adenovirus-mediated gene transfer to atherosclerotic lesions, and (b) compare the transfection efficiency, anatomic distribution of transfected cells, and duration of transgene expression achieved in normal versus atherosclerotic arteries. A recombinant adenovirus including a nuclear-targeted beta-galactosidase gene was percutaneously delivered to the iliac artery of normal (n = 25) and atherosclerotic (n = 25) rabbits. Transgene expression, assessed by morphometric as well as chemiluminescent analyses, was documented in all normal and atherosclerotic arteries between 3 and 14 d after gene transfer, but was undetectable at later time points. Transfected cells were identified as smooth muscle cells located in the media of normal arteries, and in the neointima and the vasa-vasora of atherosclerotic arteries. Two percent of medial cells, but only 0.2% of medial and neointimal cells expressed the transgene in normal and atherosclerotic arteries, respectively (P = 0.0001). Similarly, nuclear beta-galactosidase activity was higher in normal than in atherosclerotic arteries (3.2 vs. 0.8 mU/mg protein, P = 0.02). These findings indicate that atherosclerosis reduces the transfection efficiency which can be achieved with adenoviral vectors, and thus constitutes a potential limitation to adenovirus-based, arterial gene therapy.Journal of Clinical Investigation 07/1995; 95(6):2662-71. · 12.81 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: The current study was designed to determine the effect of recombinant endothelial nitric oxide synthase (eNOS) gene expression on endothelium-dependent relaxations to bradykinin in isolated canine basilar, coronary, or femoral arteries. Arterial rings were exposed ex vivo (30 minutes at 37 degrees C) to an adenoviral vector encoding either the eNOS gene (AdCMVeNOS) or the beta-galactosidase reporter gene (AdCMVbeta-Gal). Twenty-four hours after transduction, transgene expression was evident mainly in the adventitia. Expression of recombinant proteins was much higher in basilar arteries than in coronary or femoral arteries. Rings of control, AdCMVbeta-Gal, and AdCMVeNOS arteries with and without endothelium were suspended for isometric tension recording. Levels of cGMP were measured by radioimmunoassay. In AdCMVeNOS basilar arteries with endothelium, relaxations to low concentrations of bradykinin (3 x 10(-11) to 10(-9) mol/L) were significantly augmented. In contrast, in coronary and femoral arteries with endothelium, AdCMVeNOS transduction did not affect relaxations to bradykinin. Removal of the endothelium abolished bradykinin-induced relaxations in control and AdCMVbeta-Gal basilar arteries. However, in basilar arteries transduced with AdCMVeNOS even when the endothelium was removed, stimulation with bradykinin (3 x 10(-11) to 10(-9) mol/L) caused relaxations as well as increases in cGMP production. The relaxations to bradykinin were completely blocked by an NOS inhibitor, NG-nitro-L-arginine methyl ester. Electron microscopic analysis revealed that recombinant eNOS protein was expressed in fibroblasts of the basilar artery adventitia. These results suggest that genetically modified adventitial fibroblasts may restore production of NO in cerebral arteries without endothelium. Our findings support a novel concept in vascular biology that fibroblasts in the adventitia may play a role in the regulation of vascular tone after successful transfer and expression of recombinant eNOS gene.Arteriosclerosis Thrombosis and Vascular Biology 09/1998; 18(8):1231-41. · 6.34 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: Vein grafting results in the development of intimal hyperplasia with accompanying changes in guanine nucleotide-binding (G) protein expression and function. Several serum mitogens that act through G protein-coupled receptors, such as lysophosphatidic acid, stimulate proliferative pathways that are dependent on the G protein betagamma subunit (Gbetagamma)-mediated activation of p21ras. This study examines the role of Gbetagamma signaling in intimal hyperplasia by targeting a gene encoding a specific Gbetagamma inhibitor in an experimental rabbit vein graft model. This inhibitor, the carboxyl terminus of the beta-adrenergic receptor kinase (betaARK(CT)), contains a Gbetagamma-binding domain. Vein graft intimal hyperplasia was significantly reduced by 37% (P<0.01), and physiological studies demonstrated that the normal alterations in G protein coupling phenotypically seen in this model were blocked by betaARK(CT) treatment. Thus, it appears that Gbetagamma-mediated pathways play a major role in intimal hyperplasia and that targeting inhibitors of Gbetagamma signaling offers novel intraoperative therapeutic modalities to inhibit the development of vein graft intimal hyperplasia and subsequent vein graft failure.Arteriosclerosis Thrombosis and Vascular Biology 08/1998; 18(8):1275-80. · 6.34 Impact Factor