According to a recent study, published in the journal, Science, people with multiple sclerosis (MS) have high levels of pro-inflammatory TH17 immune cells in their intestines, which have been linked to the micro-organism mix in the gut and levels of disease activity.
Researchers said the findings suggest that diet, probiotics (which contain ‘good bacteria’) and therapies that regulate TH17 cells could be used to help treat MS.
T helper 17 (TH17) cells are key players in MS, and studies in animal models demonstrated that effector TH17 cells that trigger brain autoimmunity originate in the intestine.
The researchers set out to validate the crucial role of the intestinal environment in humans by promoting TH17 cell expansion in MS patients.
They found that increased frequency of TH17 cells correlates with high disease activity and with specific alterations of the gut mucosa-associated microbiota in MS patients.
By using 16S ribosomal RNA sequencing, they analysed the microbiota isolated from small intestinal tissues and found that MS patients with high disease activity and increased intestinal TH17 cell frequency showed a higher Firmicutes/Bacteroidetes ratio, increased relative abundance of Streptococcus, and decreased Prevotella strains compared to healthy controls and MS patients with no disease activity.
The research demonstrates that the intestinal TH17 cell frequency is inversely related to the relative abundance of Prevotella strains in the human small intestine.
The data demonstrates that brain autoimmunity is associated with specific microbiota modifications and excessive TH17 cell expansion in the human intestine.
The findings suggest that regulating TH17 cell expansion, along with changes in diet, could be ways to help treat MS.
Source: MS-UK (19/07/17)