Evaluation of Electrostatically Endothelial Cell Seeded Expanded Polytetrafluoroethylene Grafts in a Canine Femoral Artery Model

(1) Purpose: The purpose of this study was to evaluate the extent (luminal coverage) of the endothelial cell (EC) lining/neointimal development and the thromboresistance of electrostatically EC seeded small diameter e-PTFE vascular grafts. (2) Methods: This evaluation consisted of harvesting autologous, canine jugular vein ECs, electrostatically EC seeding the e-PTFE grafts (4 mm GORE-TEX,® Length = 6 cm), implanting the grafts in a canine femoral artery model for six weeks, and excising the graft for histological and scanning electron microscopy evaluations. (3) Results: The results of the histological evaluation (mid-graft region only) indicated that the electrostatic EC seeding significantly affected neointimal development (p<0.01) and the degree of thrombus formation (p<0.001) within the EC seeded grafts versus the untreated control grafts. Scanning electron microscopy examination demonstrated a mature, confluent endothelium with a “cobblestone” appearance on the EC seeded graft luminal surface. The control grafts demonstrated an equal distribution of SMCs through the graft wall while the electrostatically EC seeded graft sections exhibited an uneven SMC cellular distribution which was skewed toward the graft luminal surface. (4) Conclusions: The presence of electrostatic EC seeding significantly (p<0.01) enhanced the development of a neointima and reduced the incidence of thrombosis in e-PTFE grafts implanted in a canine femoral artery model. Results of the mid-graft SMC migration measurements indicate that the electrostatic EC seeding had a significant (p<0.001) impact on the acute healing of the standard wall e-PTFE vascular graft specimens.