Release of PDGF-BB and bFGF by human endothelial cells seeded on expanded polytetrafluoroethylene vascular grafts.

BACKGROUND

The majority of endothelial cell (EC) seeded graft failures are due to anastomotic neointimal fibrous hyperplasia. We investigated the PDGF-BB and bFGF release in vitro by umbilical vein EC seeded on precoated expanded polytetrafluoroethylene (ePTFE) prostheses.

MATERIALS

EC harvested from human umbilical veins were seeded into ePTFE (30 microns internodal distance, 1 cm2 in diameter) disks. ePTFE disks uncoated or precoated with collagen type I, fibronectin, and Matrigel were used, and EC seeded into plastic wells coated as ePTFE disks or uncoated plastic wells served as controls. Scanning electron microscopy study assessed EC coverage. The presence of bFGF and PDGF-BB in serum-free conditioned media from EC seeded into ePTFE grafts and EC seeded into wells was determined by the inhibition antibody-binding assay 72 h after seeding.

RESULTS

EC coverage was similar in uncoated and coated ePTFE grafts. The release of PDGF-BB and bFGF by EC seeded into ePTFE grafts was significantly higher than that observed in EC seeded into plastic wells. The release of PDGF-BB and bFGF was independent from the various substrates used in the experiments in EC seeded into either ePTFE grafts or plastic wells.

CONCLUSIONS

Our findings pointed out that in seeded ePTFE grafts, anastomotic smooth muscle cell proliferation and intimal thickening could take place underneath an intact endothelium because seeded EC may release several growth factors.