Adeno-Associated Virus-Mediated Gene Transfer in a Rabbit Vein Graft Model

Abstract

therosclerosis causing vascular disease remains one of the most important predictors for morbidity and mortality, being usually treated via angioplasty and bypass grafting. In coronary artery surgery, autologous saphenous vein and internal thoracic artery grafts are the most widely used bypass conduits. 1 Late graft failure after the operation, caused by stenoses and occlusion of the venous grafts as a result of intima hyperplasia or progression of the vascular disease, leads to a high incidence of re-operations and increased mortality. 2 The molecular mechanisms of the bypass stenoses, which are analogous to those in native vessels, make a gene therapeutic approach attractive. 2,3 The development of recombinant and adeno-viral vectors, as well as their therapeutic application in gene delivery, is an emerging field that may result in clinical acceptance on this field. Among the many vector systems, recombinant adenoviral vectors have the advantage of being produced with adequate titers for in vivo applications and being capable of transducing cardiovascular target cells effectively. 4 However, transduction is often handicapped by the induction of an immunological response in the surrounding tissue and limited by a transient gene expression. 5,6 In contrast to the adenoviral vectors, recombinant adeno-associated viral vectors (AAV), based on the serotype 2, allow long-term transgene expression after in vivo application in various tissues with low immunological responses. 7,8 The earliest experimental results demonstrated that recombinant AAV was also a promising vector for cardiovascular gene therapy because effective gene transfer into rat arteries, native jugular canine veins and the mammalian myocardium could be observed. 4,6,9 There are, however, pathophysiological differences between normal veins and veins used as bypasses, thus interest in native vein transduction is limited in cardiac surgery; furthermore, expression beyond 3 weeks is of essential importance for clinical use. 6 Higher blood pressure followed by a higher shear stress leads to unavoidable damage to the endothelium perioperatively and is responsible for the alterations in vein grafts.It was our aim to investigate the virus-mediated gene transduction with a recombinant AAV in an animal model, which could minimize the tissue damage. For this purpose, a bypass model in rabbits using the right jugular vein interposed end-to-end to the ipsilateral carotid artery was designed and AAV preparations were transduced into the venous grafts. For this preliminary experimental study, we planned no negative control group as our objective was to evaluate the transduction rate and the feasibility, not the patency rate of the bypasses. Future studies introducing iNOS into the AAV vector will include a control group to evaluate the impact of the transduction upon the patency rate of the bypasses. Methods Cell CultureThe human cervix epitheloid carcinoma cell line HeLa Adeno-Associated Virus-Mediated Gene Transfer in a Rabbit Vein Graft ModelEckehard Gerd Kilia...

Efficient Gene Transfer and Durable Transgene Expression in Grafted Rabbit Veins

“…The 24 weeks of veingraft transgene expression reported here is several months longer than we could find in any previous study, including those using adeno-associated virus (AAV) and lentivirus. 42,43 Both AAV and lentivirus are potentially useful vectors for preventing vein-graft disease. AAV has the advantage of low immunogenicity and an excellent safety record in humans; lentivirus could possibly provide longer term expression due to its ability to integrate in the genome.…”

Mechanisms of Vein Graft Adaptation to the Arterial Circulation

“…The transfected gene is not able to insert itself into the host genome and is thus diluted with cell proliferation. Adeno-associated virus has also been reported as a useful delivery vector, with reduced immunogenicity [117]. Lentivirus vector, which is a member of the retrovirus vector family, has advantages over adenovirus vectors.…”

Gene Transfer of Calcitonin Gene-Related Peptide Inhibits Macrophages and Inflammatory Mediators in Vein Graft Disease

“…In the past, Kilian et al [15] showed transfected native rabbit jugular veins with recombinant AAV vector,Moreover, low immunogenicity of AAV may also allow long-term transgene expression; Sen et al [16] showed that AAV1 have advantages over AAV2 for vascular gene delivery at low titres; Stachler et al [17] showed that mosaic AAV1 particles in a 50-100-fold enhancement in endothelial cell gene transfer and suggest that mosaic virions hold significant promise for targeted gene delivery to the vasculature.In the present study we showed that recombinant mosaic AAV2/1 facilitates an effective gene transfection in an autologous rabbit vein grafts model. Our data have shown that AAV2/1.CGRP was transfected effectively to vein grafts( Fig.…”