Does the Brain Have a Lymphatic System?

We have always thought the brain had no lymphatic system. At the same time, leukocytes and soluble molecules clearly move between the brain and the rest of the body, so we assumed that this transit of cells and molecules to and from the brain involved blood vessels, despite the blood–brain barrier.

A team from the University of Virginia reports on extensive anatomical and functional studies in mice that upend traditional teaching. The researchers demonstrated that vessels in the meninges lining the dural sinuses bear the histological markers of lymphatic vessels. Functional studies involving injection of dye into living animals demonstrated that these vessels drain cerebrospinal fluid into the deep cervical lymph nodes. Presumably, the immun…