Since the 1970s, arterial prostheses made of PET (Poly-EthyleneTeraphtalate, Dacron) and ePTFE (expanded Poly-Tetra-Fluoro-Ethylene, microporous Teflon) have been widely used to replace large (internal diameter more than 10 mm) and medium vessels (between 6 and 10 mm). It is estimated that more than a million prostheses are implanted world-wide annually. About 550,000 of these implantations are performed in the USA. Over 65% of them, however, have to be removed during the 10 following years because of complications, such as thrombosis, infection, and pseudoaneurysms. In the past few decades, much has been done to investigate the origin of these unexpected complications, but a clear theory has yet to be worked out. Nonetheless, complete endothelialization, i.e., coverage of the luminal surface by a monolayer of endothelial cells (ECs), has never been observed in synthetic vascular prostheses implanted in humans. The lack of this neo-intima is considered to be the primary cause of complications. Because this natural hemocompatible boundary inhibits thrombosis development it would be an ideal covering layer for the internal surface of prostheses.