What are endothelial cells?

Endothelial cells are specialized cells that line all the blood vessels in a single layer called the endothelium, which forms a selectively permeable barrier between the vessels and tissues. Endothelial cells perform several pivotal functions. Their primary function involves regulating the flow of substances and fluid between the bloodstream and the surrounding tissues. They also play a role in coagulation and fibrinolysis, inflammation, formation of blood vessels, and regulation of vascular tone. These cells vary in structure and function, depending on the tissue and organ. Any dysfunction of endothelial cells can lead to serious health issues, including but not limited to diabetes and cardiovascular, pulmonary, inflammatory, and immune diseases.