Deborah Devis writes:

The gut is well known for being the first line of defence against infection, but it seems it also protects our most important organ – the brain.

According to surprising new research, antibodies that defend the perimeter of the brain are normally found in, and trained by, our gut.

“This finding opens a new area of neuroimmunology, showing that gut-educated antibody-producing cells inhabit and defend regions that surround the central nervous system,” says Dorian McGavern from the National Institutes of Health, US, co-author of a paper in the journal Nature.

The work brought together researchers from the NIS and the University of Cambridge, UK. They found that special IgA antibodies were present in the outer meninges – membranes that cover the brain and spinal cord – of both mice and humans.

“This finding was completely unexpected,” says McGavern. “Prior to our study, IgA cells had not been shown to reside in the dura mater – the outer meninge – under steady state conditions.”

The researchers first found these cells in mice then confirmed that IgA was also present in human cells they collected from the meninges during surgery. [Continue reading…]