Brain endothelial cells are a type of cells that make up the blood-brain barrier, a selective barrier that controls the exchange of substances between the blood and the brain. These cells play a crucial role in protecting the brain from harmful substances and maintaining its optimal environment. Research in this area focuses on understanding the function of brain endothelial cells, their role in brain health and disease, and developing ways to target them for therapeutic interventions in neurological disorders such as Alzheimer's disease, stroke, and brain tumors. Studying brain endothelial cells can provide valuable insights into the mechanisms underlying brain function and dysfunction, and potentially lead to the development of new treatments for various brain disorders.