The Role of Repeat Administration of Adventitial Delivery of Lentivirus-shRNA-Vegf-A in Arteriovenous Fistula to Prevent Venous Stenosis Formation

Purpose: To determine if a second dose of a lentivirus mediated small hairpin RNA that inhibits Vegf-A gene expression (LV-shRNA-Vegf-A) can improve lumen vessel area (LVA) of the outflow vein of an arteriovenous fistula (AVF) and decrease venous neointimal hyperplasia. Materials and Methods: Chronic kidney disease was created in C57BL/6 mice; 28 days later; an AVF was created by connecting the right carotid artery to the ipsilateral jugular vein. Immediately after AVF creation, 5 x 10(6) plaque-forming units of LV-shRNA-Vegf-A or control shRNA was administered to the adventitia of the outflow vein, and a second dose of the same treatment was administered 14 days later. Animals were sacrificed at 21 days, 28 days, and 42 days after AVF creation for reverse transcription polymerase chain reaction and histomorphometric analyses. Results: By day 21, there was a 125% increase in the average LVA (day 21, P = .11), with a decrease in cell proliferation (day 21, P = .0079; day 28, P = .28; day 42, P = .5), decrease in alpha-smooth muscle cell actin staining (day 21, P < .0001; day 28, P < .05; day 42, P = .59), and decrease in hypoxic-stress (day 21, P < .001; day 28, P = .28; day 42, P = .46) in LV versus control shRNA vessels. Conclusions: A second dose of LV-sbRNA-Vegf-A administration results in a moderate improvement in LVA at day 21.