An article in the magazine Nature describes a break-through discovery that the brain is connected to the body’s immune system through tiny lymphatic vessels that no one previously knew existed. They were recently discovered in research involving rat brains.

The lymphatic vessels had not been identified before because they are very small and well-hidden, and closely follow a blood vessel that goes into the sinuses where imaging is more difficult. A researcher said: “if you didn’t know what you were looking for, you would not see them.” This new knowledge means we can now begin to study and understand the neuro-immune interaction.

The major significance of this discovery is felt to be the chances to now better investigate neurological diseases such as autism, Alzheimer’s, and MS. For example, in Alzheimer’s it is thought that the brain accumulates protein chunks, and this may be because the protein is not being efficiently removed by the newly-discovered lymphatic vessels. The researchers believe that there may be numerous other neurological diseases which are somehow related to malfunctioning lymphatic vessels in the brain, and that this new discovery may lead to new ways of treating those diseases. As one of the authors said, “They will have to change the textbooks now.”