Endothelial cell migration onto metal stent surfaces under static and flow conditions

Restenosis associated with intimal hyperplasia and thrombosis at sites of balloon angioplasty or stent placement remains an important clinical problem. It is likely that loss or damage to the arterial endothelium associated with these interventional procedures as well as the rate of its restoration plays a critical role in the extent of restenosis. Migration of arterial endothelial cells from adjacent intact endothelium is the predominant source of cells involved in re-endothelialization of the injured site. In this paper, we review the influence of hemodynamics on endothelial cell migration, both in vivo and in vitro. In addition, we present recent in vitro studies demonstrating the importance of the nature of metal substrates in modulating endothelial cell migration rate. Finally, we review the cellular and molecular mechanisms likely involved in governing endothelial cell migration, and relate them to a possible scenario of endothelial response to injury at sites of arterial intervention. Understanding the important factors regulating endothelial migration may provide insights that will ultimately lead to methods to accelerate endothelial healing and reduce the occurrence of arterial restenosis.