In this movie Dr. Evelina Sjöstedt shows the cellular organization of the blood brain barrier in 3D and explains how this system can protect the brain against unwanted molecules, but also can be a problem when developing new treatments for diseases of the brain.

Normal brain function is dependent on integrity of the blood brain barrier and regulation of the cerebral blood flow, which both are controlled by a minimal functional unit called the neurovascular unit. The neurovascular unit is built of cells and extracellular matrix components that locally maintain homeostasis. The astrocytes and endothelia cells are the major components of the neurovascular unit and the interplay between these cells form a tight network around the blood vessels of the brain that coordinates what molecules are allowed to enter the brain and what molecules should be excreted back into the blood stream.

Link to movie