Researchers have found that the brain is directly connected to the immune system via vessels previously believed not to exist.
A professor in The University of Virginia's (UVa) Department of Neuroscience and director of UVa's Center for Brain Immunology and Glia, Jonathan Kipnis said the discovery, "changes entirely the way we perceive the neuro-immune interaction. We always perceived it before as something esoteric that can't be studied. But now we can ask mechanistic questions."
Despite the fact that the lymphatic system has been studied several times before, its quite surprising that the vessels connecting these two bodily systems have escaped detection for such a long time.
What also makes the research important is that the discovery could have a significant impact on the study and treatment of neurological diseases including multiple sclerosis, Alzheimer's disease and autism, according to records on Medical News Today.
Prof. Kipnis explained, Instead of asking, 'How do we study the immune response of the brain?', 'Why do multiple sclerosis patients have the immune attacks?', now we can approach this mechanistically."
"Because the brain is like every other tissue connected to the peripheral immune system through meningeal lymphatic vessels," he added.
The unknown vessels were identified owing to the work of post-doctoral fellow in Prof. Kipnis' lab, Antoine Louveau, DNA noted.
Louveau developed a new technique to count the membranes covering the brains of a mouse on a single slide. This involved securing the membranes called meninges to the skullcap before dissection.
In the distribution of the immune cells he was examining, Louveau noticed a vessel-like pattern.
"I called Jony [Kipnis] to the microscope and I said, 'I think we have something,'" Louveau said.
It just needed a simple test for lymphatic vessels to confirm their presence.
"I really did not believe there are structures in the body that we are not aware of. I thought the body was mapped," Prof. Kipnis says. "I thought that these discoveries ended somewhere around the middle of the last century. But apparently they have not."
Explaining why it was probably not been identified before, Prof. Kipnis says that the vessels are "very well hidden." He continued, "It's so close to the blood vessel, you just miss it. If you don't know what you're after, you just miss it."
The next step now is determining how the vessels might be involved in diseases involving the brain and the immune system, such as Alzheimer's.
"We believe that for every neurological disease that has an immune component to it, these vessels may play a major role," Kipnis said.
