Endothelial cells adherent to expanded polytetrafluoroethylene express the intercellular adhesion molecule-1.

Abstract

The foreign body reaction caused by implanted biomaterials is not fully characterized. To evaluate the effect of an expanded polytetrafluoroethylene (ePTFE) surface on the binding of monoclonal antibodies against the intercellular adhesion molecule (ICAM-1) by adherent endothelial cells, an in vitro bioassay was developed. Human saphenous vein endothelial cells (HSVEC) and human umbilical vein endothelial cells (HUVEC) were grown to confluency on fibronectin-pretreated ePTFE and on fibronectin-pretreated polystyrene culture flasks used as controls. Cells were assayed for size, density, viability, and binding of anti-ICAM-1 antibodies. Human peripheral blood leukocytes (PBLs) were then cocultured with HUVEC adherent to ePTFE and control polystyrene and HUVEC were assayed for the binding of anti-ICAM-1 antibodies. The adherence of HSVEC and HUVEC to ePTFE resulted in a twofold increase in the binding of monoclonal antibodies against ICAM-1 compared with controls at 48 hours (p < 0.005). The addition of PBLs to the adherent HUVEC resulted in a four- to eightfold increase in anti-ICAM-1 antibody binding on ePTFE and polystyrene, respectively, at 24 hours. Adherence of endothelial cells to ePTFE results in an increase in the binding of anti-ICAM-1 antibodies. Coculture of adherent HUVEC and PBLs results in a marked increase in the number of cells binding ICAM-1 antibodies. These data support the conclusion that ePTFE is associated with the activation of adherent cells, which is one aspect of a multicellular inflammatory response.