Effect of retroviral transduction on human endothelial cell phenotype and adhesion to Dacron vascular grafts

Retroviral transduction for genetic enhancement of endothelial cell (EC) anti-thrombotic phenotype offers potential for improving the clinical success of vascular graft seeding; however, application of this technique may bring concomitant alteration in cell functionality.

Human microvascular ECs were transduced with a retroviral vector encoding for the marker gene beta-galactosidase. Transduced endothelial cells (rtECs) and nontransduced endothelial cells (ntECs) were evaluated by flow cytometry for expression of intercellular adhesion molecule (ICAM)-1 and tissue factor (TF) on both smooth (coverslips) and graft (Dacron, 6 mm inside diameter) surfaces under static and shear exposed conditions. Graft EC retention was measured after 6-hour pulsatile perfusions. Platelet and neutrophil adherence was measured on perfused coverslips.

Lower levels of ICAM-1 were expressed by rtECs on coverslips under both static (p < 0.01 vs static ntECs) and shear exposed conditions (p < 0.01 vs static and shear ntECs). Accordingly, fewer polymorphonuclear leukocytes adhered to rtEC monolayers (p < 0.01 vs ntECs). No difference in ICAM-1 and TF expression by static graft seeded rtECs and ntECs was observed. However, graft-seeded rtECs that were exposed to wall shear stress displayed less TF than sheared ntECs (p < 0.05). Transduction did not affect EC retention to the sheared graft surface.

These data suggest that retroviral transduction does not elicit a prothrombotic/proinflammatory phenotype, rather indices of these states appear in some conditions to be reduced. Further, transduction does not adversely affect EC adherence to Dacron graft surfaces under arterial hemodynamics.