Endothelial cell interactions with native surfaces

Since native vessels are presumably the ideal surface for endothelial cells, we have examined endothelial cell interactions with natural surfaces as a standard to determine the possibilities obtainable on a surface. We have examined three separate types of natural surfaces including human amnion, superficially-injured human arteries, and tanned bovine carotid arteries. When basement membrane collagen is a principal component of a surface, such as with amnion or a superficially denuded large vessel, very rapid cell attachment and spreading occurs. Intact confluent monolayers covering 100% of the amnion surface are present as early as one hour. Human arteries superficially injured to denude their endothelium also exhibit excellent affinity for EC adherence and spreading. Endothelial monolayers cover 80.8% (+/- 5.3) of this surface after one hour, with 91.4% (+/- 1.2) coverage after two hours. For tanned bovine carotid arteries, one and two hour endothelial cell incubation results in coverage of 59.2% (+/- 1.3) and 75.9% (+/- 4.1), respectively. This surface is composed of interstitial collagen of the arterial wall in medial and adventitial layers. Electron microscopy reveals excellent endothelial cell spreading with little or no exposed underlying basement membrane. This suggests that polymeric surfaces designed to mimic injured native surface could allow an endothelialized surface to develop within minutes to hours.