Prelining autogenic endothelial cells in allogeneic vessels inhibits thrombosis and intimal hyperplasia: an efficacy study in dogs.

BACKGROUND The long-term patency rates in vascular transplants (diameter<3.0-4.0mm) are very low due to thrombus formation and intimal hyperplasia. A possible mechanism is the loss of the endothelial cells (ECs) lining. Previous attempts to reseed ECs had poor results due to seeded cell loss, severe antigenicity, and low compliance. The objectives of this study were to generate an allogeneic vascular substitution with autogenic ECs and low antigenicity. METHODS ECs from mongrels were obtained and multiplied in vitro, then seeded to the allogeneic vein luminal surface, which was preserved by freeze-drying radiation. The cultivated cells' secretory function was confirmed by von Willebrand factor detection. The allogeneic vascular was then transplanted into animals' necks in situ. The physical properties, EC state, and vascular structure of the allogeneic vascular grafts were studied. RESULTS The secretory function of ECs did not vary in vitro. The expression level of MHC-II antigen in freeze-dried radiation-treated vasculature was lower than normal fresh vasculature (P<0.05). ECs covered the vascular inner surface and adhered tightly after implantation. As assessed by scanning electron micrograph, most ECs adhered tightly, and the cell polarity changed in accordance with the direction of the force. Allograft blood vessels with autogenic ECs implanted showed significant decreases in both thrombosis and intimal hyperplasia. CONCLUSION Allograft blood vessels seeded with autogenic ECs improved the patency of small-diameter grafts in a canine model. Our study showed a significant decrease in both thrombosis and intimal hyperplasia.