In vitro evaluation of electrostatic endothelial cell transplantation onto 4 mm interior diameter expanded polytetrafluoroethylene grafts

Purpose: To perform an in vitro evaluation of electrostatic endothelial cell transplantation of human umbilical vein endothelial cells (HUVEC) onto segments of 4 mm internal diameter expanded polytetrafluoroethylene (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 physiologic shear stress (15 dynes/cm(2)) under steady now conditions within a flow loop system. Biochemical assays were performed on freshly transplanted grafts by means of radioimmunoassay for prostacyclin and thromboxane A(2). Results: There was a 30% loss of HUVEC after 30 minutes of shear stress exposure from the grafts subjected to gravitational transplantation with no additional significant (alpha = 0.05) loss after 120 minutes. Grafts subjected to electrostatic transplantation had no significant (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 +/- 6274 HUVEC/cm(2)) retained 2.3 times more HUVEC than the counterparts subjected 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 method of cell transplantation. Conclusions: (1) The electrostatic transplantation technique was superior to the gravitational transplantation technique in terms of cellular retention when the ePTFE grafts were exposed to physiologic shear stress. (2) Production of prostacyclin and thromboxane A(2) did not differ between transplanted HUVEC subjected to gravitational or electrostatic procedures.