Medical scientists have discovered secret tunnels that are said to be linking the human brain with the skull.
The discovery of the secret tunnels between the brain and skull could potentially lead to breakthroughs that could help brain disorder research studies. The researchers believe that the tubes act as passageways for the immune cells produced by the bone marrow in the skull to reach the brain quickly.
“We always thought that immune cells from our arms and legs traveled via blood to damaged brain tissue. These findings suggest that immune cells may instead be taking a shortcut to rapidly arrive at areas of inflammation,” Francesca Bosetti, the program director at the NIH’s National Institute of Neurological Disorders and Stroke which funded the study, said in a statement.
Inflammation plays a critical role in many brain disorders and it is possible that the newly described channels may be important in a number of conditions. The discovery of these channels opens up many new avenues of research.
Previously, neuroscientists believed that immune cells were being transported to the brain through the bloodstream from other parts of the body. Apparently, the recently discovered tunnels provide a shortcut for the immune cells to travel to the brain and deal with the inflammation caused by stroke, injury, or any brain disorders.
With the help of advanced technologies and cell-specific dyes in mice, researchers from the Harvard Medical School and Massachusetts General Hospital in Boston spearheaded by Dr. Matthias Nahrendorf identified whether the immune cells traveling to the stroke and meningitis-damaged brain tissues are from the bone marrow in the skull or the large leg bone called the Tibia.
During their study, Dr. Nahrendorf and his colleagues focused on a specific kind of immune cell called neutrophils. This cell is said to be the first to always arrive at the injury site of the brain.
Using the technique developed by the researchers, they were able to tag the immune cells with fluorescent membrane dyes that act as cell trackers. The team reportedly treated the cells with colors and then injected them into the bone marrow sites in their mice models. The scientist injected red-dyed cells into the skull and green-dyed cells into the Tibia.
Once all the dyed cells had settled in, the researchers then induced several models of acute brain inflammation like stroke and chemically induced meningoencephalitis.
During the experiment, the research team discovered that the skull had contributed significantly more neutrophils to the brain than the tibia following a stroke or meningitis. However, it led to the question of how the neutrophils were being delivered. That’s when they discovered the hidden passageways.
“We started examining the skull very carefully, looking at it from all angles, trying to figure out how neutrophils are getting to the brain. Unexpectedly, we discovered tiny channels that connected the marrow directly with the outer lining of the brain,” Dr. Nahrendorf explained.
At the moment, Nahrendorf and his team have to conduct more experiments and further research to determine the other kinds of cells that use the secret tunnels aside from the neutrophils. The team’s study has been published in the journal Nature Neuroscience.