During flare-ups of the autoimmune disease multiple sclerosis, certain intestinal immune cells could move to reduce inflammation in the central nervous system.
In people with multiple sclerosis (MS), the immune system attacks the protective sheath that surrounds nerve fibres. Jen Gommerman at the University of Toronto in Canada and her colleagues tracked plasma cells — a type of immune cell — in mice bred to have MS-like symptoms. The researchers discovered that in mice that had central-nervous-system inflammation, plasma cells that produce the antibody IgA migrate from the gut to the brain and spinal cord. This finding is supported by the team’s analysis of fecal samples from people with MS during disease flare-ups.
Compared with mice that have normal numbers of plasma cells, mice engineered with a shortage of plasma cells experienced more serious MS-like symptoms. But these mice improved when given a transfusion of plasma cells from the intestines of healthy mice.
The discovery indicates that communication between the gut and nervous system is an important mechanism in MS, the authors say.