Th17

Berberine, plant compound, eases disease severity in MS mouse model

Treatment with berberine, a compound found in many plants, eased disease severity and showed anti-inflammatory effects in a mouse model of multiple sclerosis (MS), a new study reports. “These results confirmed that treatment with berberine efficiently improved the disease in the animal model of MS,” the researchers wrote, noting…

TH17-suppressing Pregnancy Proteins May Be MS Therapeutic Target

Proteins called PSGs suppress the pro-inflammatory activity of immune Th17 cells during pregnancy, potentially playing a protective role against complications and miscarriage, a study finds.Ā  The impaired regulation of Th17 is associated with pregnancy complications, like preeclampsia and preterm delivery ā€” and also with the development…

Protein That Turns Certain T-cells into Inflammatory Agents Identified in Early Study

A protein called Satb1 appears to be the "on switch" that turns a type of T-cell called Th17 from its typical protective role into one that is disease-causing, and key in the development of multiple sclerosis (MS) and other inflammatory autoimmune disorders, a study reports. These findingsĀ suggest thatĀ Satb1 may be a therapeutic target for autoimmune diseases like MS. The research article, ā€œSatb1 regulates the effector program of encephalitogenic tissue Th17 cells in chronic inflammation,ā€ was published in the journalĀ Nature Communications. Immune cells called T-helper 17 (Th17) cells play a range of roles in immunity, including protecting against infecting pathogens ā€” bacteria, viruses, and other microorganisms that can cause disease. But Th17 cells are also players in the development of such autoimmune diseases as MS, psoriasis, inflammatory bowel disease, and rheumatoid arthritis. This is because Th17 cells can be stimulated to become T-cells that engage in pathogenic, or disease-causing, immune programs. How Th17 cells switch from their typical and helpful immunity role to that of a pathogenic actor has not been resolved, although it is thought critical to treating inflammatory autoimmune diseases. An international team led by researchers at Osaka University and Kyoto University, in Japan, tried to identify the mechanism behind the disease-causing program of Th17 cells. To do so, they built upon previous findings showing that a protein regulator called Satb1 is important in the development of Th17 cell subsets. "We have known for some time that Satb1 is indispensable for the development of T-cells in the thymus. However, how it is involved in the regulation of pathogenic processes of Th17 cells in inflamed tissues had not been examined," Keiko Yasuda, MD, the study'sĀ lead author, said in a press release. Researchers used a standard mouse model of MS, called experimental autoimmune encephalomyelitis (EAE) mice. These animals had genetically-modified Th17 cells that lacked Satb1. Researchers tested how Th17 cells lacking Satb1 acted when subject to inflammatory conditions, and how they were stimulated to activate a "pathogenic effector program." Interestingly, these modified mice were resistant to the development of EAE, or MS-like, disease. Researchers saw fewer Th17 cells infiltrating the animals' spinal cord. Also, Th17 cells lacking Satb1 showed poorer production of key pathogenic signaling molecules in autoimmunity, notably one called granulocyte-macrophage colony-stimulating factor (GM-CSF). GM-CSF is known to cause localized tissue inflammation in MS and other inflammatory autoimmune diseases. Researchers went on to show that Satb1 can act as a switch between benign and pathogenic Th17 cells, depending on their exposure to healthy or inflammatory conditions. They found molecules that boost the pathogenicity of Th17 cells, such as Bhlhe40, and molecules that promote normal immune function, such as PD-1. Ā Of note, PD-1 is shut down when Th17 cells engage in their pathogenic effector program. These results showed Satb1 to be a key regulator of Th17 cell pathogenicity in these MS mice. Halting Th17 cells from making Satb1 may offer a way of treatting various autoimmune diseases. ā€œTogether, our findings, in addition to providing novel insights into the molecular mechanisms underlying the pathogenic program of tissue Th17 cells in mice, may help design novel immunotherapeutic approaches such as small molecule modifiers of Satb1 for the treatment of autoimmune diseases,ā€ the researchers wrote. Future studies are needed to confirm these results in people. A previous study in people also suggested a link between Satb1 and the pathogenic function of Th17 cells in the central nervous system of MS patients. Overall, "our results suggest that manipulating Satb1 gene expression in Th17 cells could form the basis of novel treatments for various autoimmune diseases caused by Th17 cells. If we can prevent the pathogenic processes of Th17 cells, we may be able to alleviate or even eliminate disease symptoms," concluded Shimon Sakaguchi, PhD, one of the study's senior authors.

High Levels of Pro-Inflammatory Immune Cells in Intestines May Promote MS Activity, Study Reports

People with multiple sclerosis have high levels of pro-inflammatory TH17 immune cells in their intestines that correlate with change in the micro-organism mix in their gut and the levels of their disease activity, a study reports. Researchers said the findings suggest that diet, probiotics and therapies that regulate TH17 cells could help treat MS. Probiotics are supplements containing beneficial bacteria. The study, ā€œHigh frequency of intestinal TH17 cells correlates with microbiota alterations and disease activity in multiple sclerosis,ā€ was published in the journal Science. Research has shown that TH17 cells, also known as T helper 17 cells, play a role in the development of MS. In fact, they were the first harmful immune T-cells to infiltrate the central nervous system, according to studies in animals Where TH17 cells become activated has been unclear, however. Studies in mice suggested it was mainly in the small intestine. Research has also indicated that their activation increases the potential for a person to develop an autoimmune brain disease like multiple sclerosis. An autoimmune disease occurs when the immune system, which defends the body against disease, decides that a person's healthy cells are foreign, and attacks those cells. Researchers decided to see if the findings in mouse models of MS applied to people with the disease. They discovered a link between higher levels of TH17 cells in MS patients' intestines and autoimmune brain problems. They also found a correlation between higher levels of TH17 cells and changes in patients' gut microbiome. The team then identified which bacteria were changing in the gut. Patients with increased levels of TH17 cells and higher disease activity had a higher ratio of Firmicutes to Bacteroidetes bacteria and more Streptococcus strains in their gut, particularly Streptococcus mitis and Streptococcus oralis. Previous studies have shown that these species promote TH17 cell differentiation in humans. Cell differentiation involves a cell transforming from one cell type to another ā€” usually a more specialized type. This dramatically changes a cell's size, shape, metabolic ā€” or fuel-burning ā€” activity, and responsiveness to signals. Some studies have suggested a link between T-cell differentiation and brain autoimmune diseases. ā€œOn the basis of our findings, we speculate that, under certain conditions, or because of still unknown virulence factors, these Streptococcus strains can colonize the small intestine and favor TH17 cell differentiation in the human gut mucosa [linings],ā€ researchers wrote. In addition to more Streptococcus bacteria, the team detected lower levels of Prevotella bacteria in MS patients with disease activity than in healthy controls or patients with no disease activity. This decrease may also promote TH17 cell differentiation because ā€œPrevotella is capable of producing the anti-inflammatory metabolite propionate that limits intestinal TH17 cell expansion in mice," the researchers wrote. Overall, the team concluded that ā€œour data demonstrate that brain autoimmunity is associated with specific microbiota modifications and excessive TH17 cell expansion in the human intestine.ā€ The findings suggest that regulating TH17 cell expansion, along with changes in diet aimed at regulating intestinal linings, could be ways to help treat MS.

#ACTRIMS2017 – Some Fatty Acids in Diet Help, Others Hurt Immune System, Study Reports

Short-chain dietary fatty acids, such as propionate, drive the production of regulatory immune T-cells in patients with multiple sclerosis (MS), while long-chain acids promote T-cells that are involved in inflammatory processes. Since the beneficial fatty acids are safe and can be obtained as over-the-counter dietary supplements, researchers suggest they could…

Brickell Biotech Targeting MS and Other Autoimmune Diseases

Brickell Biotech, Inc., a pharmaceutical company developingĀ novel therapies in the field of dermatology, recently announced it has exclusive worldwide rights over a series of new, retinoic acid-related orphan nuclear receptor gamma (RORy) inhibitors from the New York University (NYU) and Orca Pharmaceuticals.Ā As part of the agreement, Brickell will be…