Dietary change seems to alter the symptoms of the autoimmune disorder multiple sclerosis (MS) — an effect that could be due to certain gut bacteria that regulate immune responses, two studies suggest.
Sergio Baranzini at the University of California, San Francisco, and his colleagues transplanted bacteria taken from the intestines of people with MS into mice. They found that when MS-like disease was induced in the mice, the animals were more severely affected than mice given bacteria from healthy people. The mice also had fewer regulatory T cells, which dampen inflammation, and higher levels of inflammatory proteins.
In a separate study, Hartmut Wekerle and Gurumoorthy Krishnamoorthy at the Max Plank Institute of Neurobiology in Martinsried, Germany, and their colleagues assessed the microbiomes of 34 sets of identical twins in which just one twin had MS. Mice colonized with gut microbes from the healthy twins produced more interleukin-10, an anti-inflammatory protein that protects against autoimmune disease, than mice treated with samples from twins with MS.