Direct link between brain, lymph system found in humans

HELSINKI, Finland, June 15 (UPI) -- Researchers in Finland confirmed a suspected link between the brain and lymphatic system using new imaging technology to answer the question of brain fluid draining into the lymph system without a direct link between the two.

The research team at the University of Helsinki said the discovery could be significant for the way brain diseases and disorders are handled.

"We have recently discovered that in the eye, which is another immune-privileged organ previously considered to lack lymphatic circulation, there exists a lymphatic-like vessel," Aleksanteri Aspelund,a researcher at the University of Helsinki, said in a press release. "This led us to investigate the lymphatic nature of the brain in more detail."

Although they had to develop an effective method of seeing the vessels, the researchers were able to find them in the meningeal linings of a mouse, following to where they drain out of the skull through the foramina at its base, alongside arteries, veins and cranial nerves.

The lymphatic vessels hadn't been found before, said medical student Salli Antila, because unless you know what you're looking for, it's easy to miss them.

It is highly possible that lymphatic clearance of the brain will help researchers working on solutions to diseases characterized by the pathological accumulation of misfolded proteins or fluid in the brain, as well as other neuro-immunological diseases.

"This incredible finding completely changes our understanding of the brain anatomy and gives a chance to look at brain diseases from a completely new angle," Aspelund said.

The study is published in the Journal of Experimental Medicine.