IN-VITRO EVALUATION OF ELECTROSTATIC ENDOTHELIAL-CELL TRANSPLANTATIONONTO 4 MM INTERIOR DIAMETER EXPANDED POLYTETRAFLUOROETHYLENE GRAFTS

Purpose: To perform an in vitro evaluation of electrostatic endothelia l cell transplantation of human umbilical vein endothelial cells (HUVE C) onto segments of 4 mm internal diameter expanded polytetrafluoroeth ylene (ePTFE) vascular prostheses. Methods: This evaluation consisted of exposing vascular graft segments that had been subjected to either electrostatic or gravitation transplantation with HUVEC to a physiolog ic shear stress (15 dynes/cm(2)) under steady now conditions within a flow loop system. Biochemical assays were performed on freshly transpl anted grafts by means of radioimmunoassay for prostacyclin and thrombo xane A(2). Results: There was a 30% loss of HUVEC after 30 minutes of shear stress exposure from the grafts subjected to gravitational trans plantation with no additional significant (alpha = 0.05) loss after 12 0 minutes. Grafts subjected to electrostatic transplantation had no si gnificant (alpha = 0.05) loss of HUVEC during exposure to physiologic shear stress. Furthermore, after 120 minutes of shear-stress exposure, the grafts subjected to electrostatic transplantation (78,420 +/- 627 4 HUVEC/cm(2)) retained 2.3 times more HUVEC than the counterparts sub jected to gravitational transplantation (34,427 +/- 4637 HUVEC/cm(2)). The biochemical assay results indicated no significant (alpha = 0.05) production of prostacyclin or thromboxane A(2) regardless of the meth od of cell transplantation. Conclusions: (1) The electrostatic transpl antation technique was superior to the gravitational transplantation t echnique in terms of cellular retention when the ePTFE grafts were exp osed to physiologic shear stress. (2) Production of prostacyclin and t hromboxane A(2) did not differ between transplanted HUVEC subjected to gravitational or electrostatic procedures.