Objective: To study the feasibility of adenovirus mediated gene transfer into vein grafts and the role of the prourokinase gene in protecting vein grafts from thrombosis.
Methods: Fifty-two Wistar rats underwent implantation of reversed autologous jugular vein interposition grafts in the common carotid arteries. Jugular veins were excised and distended with solution containing three different adenovirus vectors (Adv5-CMV, group I; Adv5-CMV/LacZ, group II; Adv5-CMV/Pro-UK, group III) for 30 min, then the jugular veins were reversed and interposed into the divided carotid arteries, and end-to-end anastomoses were performed. The amount of 51Cr-labeled platelets in vein grafts of group I and group III was counted 24 hours postoperatively. On the 14th day, the vein grafts were harvested to examine beta-galactosidase activity and prourokinase (Pro-UK) activity and observe thrombosis in vein grafts.
Results: Extensive blue coloration in the area of intima and media of each vein graft in group II was observed. No blue coloration was seen in group I. Pro-UK activity was not detected in the vein grafts of group I. In group III, the amount of Pro-UK gene expression was 308 IU/g tissue. The amount of 51 Cr labeled platelets in group I and group II was (123.7 +/- 19.4) x 10(6)/g dry wt, (34.4 +/- 5.3) x 10(6)/g dry wt, respectively. The thrombosis rate and occlusion rate of the vein grafts in group I were 30% and 10%, respectively. In group III, all vein grafts were patent and free of thrombosis.
Conclusions: Ex vivo gene transfer before vein grafting is feasible using replication deficient recombinant adenovirus and results in a high level of gene expression in vivo. Direct transfer of the Pro-UK gene into vein grafts may prevent thrombosis.