Growth and fibrinolytic parameters of human umbilical vein endothelial cells seeded onto cardiovascular grafts.

It was the aim of this study to investigate possible effects of biomaterials used to produce vascular grafts on the fibrinolytic system of endothelial cells. Therefore growth conditions for human umbilical vein endothelial cells on polytetrafluoroethylene and on polyurethane were optimized. Tissue culture polystyrene was used as a control material. We could demonstrate that precoating of the materials with fibronectin significantly increased the growth rate of human umbilical vein endothelial cells on these materials. Furthermore, we showed that human umbilical vein endothelial cells grown on polytetrafluoroethylene or polyurethane released more plasminogen activator inhibitor-1 and tissue type-plasminogen activator into the conditioned media than did human umbilical vein endothelial cells grown on tissue culture polystyrene. Human umbilical vein endothelial cells cultured on polytetrafluoroethylene also deposited more plasminogen activator inhibitor-1 into the extracellular matrix than did control cells grown on tissue culture polystyrene. Our results give evidence that human umbilical vein endothelial cells grown on two biomaterials used to construct vascular grafts, namely polytetrafluoroethylene and polyurethane, produce tissue-type plasminogen activator as well as plasminogen activator inhibitor-1, two major components of the fibrinolytic system also expressed by endothelial cells in vivo. In conclusion, our data suggest that endothelial cells grown on vascular grafts show functional integrity concerning their fibrinolytic system, which in turn might contribute to reduce the thrombogenic properties of the graft material.