Endothelial cells are a type of cell that lines the interior surface of blood vessels and lymphatic vessels. They play a crucial role in regulating blood vessel function, including controlling blood clotting, inflammation, and the movement of substances in and out of the blood vessels. Endothelial cells also contribute to the formation of new blood vessels through a process known as angiogenesis. Research in this area focuses on understanding the role of endothelial cells in various physiological and pathological processes, including cardiovascular disease, cancer, and inflammation, with the aim of developing new therapies and treatments.