Neuroscientists have discovered a previously unknown direct connection between the brain and the immune system - a finding that could significantly impact the treatment of brain disorders like Alzheimer's disease, multiple sclerosis and autism.
Dr Kevin Lee, chairman of the University of Virginia's neuroscience department found the discovery surprising. ''The first time these guys showed me the basic result, I just said one sentence: 'They'll have to change the textbooks,'' he said in a press release Monday.
Dr Jonathan Kipnis, University of Virginia's Center for Brain Immunology and Glia who shared the sentiment: "When we discovered the lymphatic vessels we were very very surprised, because based on the textbooks - these vessels do not exist," Kipnis said in an email to The Huffington Post.
While according to previous research there was no direct connection between the brain and the lymphatic system, the new findings, recently published in the journal Nature, present a model of the lymphatic system that includes the brain.
Though the lymphatic system does not form part of the immune system, it carries lymph, a clear fluid filled with white blood cells that flush toxins from the body. The lymphatic system, which has connections with every other system in the body, was believed to end at the base of the skull.
According to experts, the discovery might help explain links between poor physical health and brain disorders including Alzheimer's and depression.
They point out that the findings could provide a firm biological basis for growing evidence that mental health and the state of the immune system were closely intertwined.
According to Kipnis, the researchers believed that for every neurological disease that had an immune component to it, these vessels might play a major role.
In Alzheimer's there were accumulations of big protein chunks in the brain and they thought these might be accumulating in the brain because they were not being efficiently removed by these vessels, he said.
A condition like diabetes, that impacted the immune system throughout the body, could also be impairing the brain's ability to clear away the toxic proteins that were the hallmarks of the disease, he added.
According to the researchers, the precise role of the vessels remained only a speculation at this stage, and putting these questions to the test would be the focus of the next phase of their research.