Seeding of expanded polytetrafluoroethylene (ePTFE) vascular grafts. A morphological study of porcine endothelial and fibroblast cells.

The need to improve clinical results with small and medium calibre grafts has led to extensive research on cell seeding of prosthetic materials. Numerous problems remain regarding identification, seeding, adhesion and survival of the cells attached. We have studied the behaviour of seedings of endothelial and fibroblast cells on ePTFE grafts. Scanning electron microscopy allows us to observe the morphological characteristics and their interaction with the biopolymers. It has been possible to differentiate both cellular types by their characteristics and interactions with the ePTFE. At the same time, from this "in vitro" study it can be concluded that the time needed to obtain a stable and confluent monolayer on ePTFE pretreated with fibronectin is between 18 hours to 4 days for endothelial cells, and 24 hours for fibroblasts. These would be the optimal time periods for "in vivo" grafting of the seeded prostheses.