The international MS microbiome study (iMSMS, www.imsms.org) may shed light on the role the gut flora plays in MS. Many people are familiar with the concept of gut flora- the bacteria and other organisms that live in the digestive tract quietly, not causing disease- but often my patients are less familiar with the terms microbiota and microbiome.
Here are a few definitions:
microbiota– the microorganisms that populate our bodies without causing infection
microbiome- the complement of genes carried by the microbiota as a whole
Although microbiota reside in other organs in the body, the gut harbors the largest and most diverse collection of organisms. Strikingly, we harbor 10 times more cells and 150 times more DNA from bacterial than human origin. This fact alone is believed to have profound implications in how our immune system relates to our external environment.
Fascinating research on the role of the gut microbiota in the mouse model of MS (EAE,experimental autoimmune encephalomyelitis), has shown a prominent role for gut flora in certain strains of mice. Mice can be raised in a germ-free environment, thereby disallowing for colonization of the GI tract. In some strains of mice, EAE is less severe (or even absent) without gut microbiota. We then can selectively colonize the gut with specific strains of organisms, and some seem to be protective while others appear disease-promoting. (1)
Dr. Sergio Baranzini is a Professor of Neurology at UCSF and the principal investigator of the iMSMS. This international effort aims to recruit 2000 patients and ‘matched controls’ to better understand the role of the microbiota in multiple sclerosis. In time, this study may shed light on the process of MS, but also may open new avenues for treating and/or preventing this disease. It is an observational study and will not affect your current treatment regimen.
If you are interested in receiving more material regarding participation in the microbiome project at UCSF, visit our website iMSMS.org or call 415-502-7197.
1. Lee YK, Proinflammatory T-cell responses to gut microbiota promote experimental autoimmune encephalomyelitis. Proc Natl Acad Sci , 2011 Mar 15;108 Suppl 1:4615-22.
Elizabeth Crabtree, MD
Associate Clinical Professor of Neurology
Director of Patient Education and Support
UCSF Multiple Sclerosis Center