what are endothelial cells

Endothelial cells are cells that line the inner surface of blood vessels and lymphatic vessels, forming an interface between circulating blood or lymph in the lumen and the rest of the vessel wall. The endothelial cells serve as a permeable barrier to regulate the passage of substances between blood-stream and surrounding tissue. In basic research, endothelial cells are critical in applications related to wound healing, angiogenesis, blood brain barrier (BBB), inflammatory processes, diabetes and other cardiovascular diseases.