VEGF-Transfected Human Endothelial Cell Coating on Stents Promotes Re-endothelization and Inhibits In-stent Restenosis

The effects of seeding of endothelial cells transfected with vascular endothelial growth factor onto stents on promoting re-endothelization and inhibiting in-stent restenosis (ISR) were observed in this paper. Human umbilical vein endothelial cell (HUVEC) line with the stable expression of vascular endothelial growth factor (VEGF) gene was established. A novel rotational culture device was used to improve the adhesion of transgenic endothelial cells. The morphology, amount and density of cells on the surface were observed respectively by SEM, fluorescence microscope and the image processing technique. An extracorporeal circulation system was used to simulate the transfer process and check the cells adhesion and growth on the modified surface after stenting in vitro. Bare metal stent (BMS), and endothelial cells coated stent (ECS) were deployed in the infra-renal abdominal aorta to detect the efficiency on promoting re-endothelization and inhibiting in-stent restenosis in vivo. The results showed that stents seeded with HUVECs transfected with VEGF were observed by SEM and fluorescence microscope. In vitro studies revealed that cells adhered on the surface of stents confermly. And the covered rate of the surface achieved more than 90 percentages after 24 h. Immunofluorescence of VEGF also showed the high rate of coverage. Cells would lose a few after stent implantation in the flow system. After 6 h, cells kept increasing. ECs-coated stent was associated with a significant reduction in neointimal area and percentage stenosis only compared with bare metal stents. We conclude that ECs-coated stents significantly inhibit neointimal hyperplasia and promote re-endothelization on the surface of stent.