T-cells

An experimental treatment known as OB-002, that works to block an inflammatory molecule in the brain, prevented the development of lesions there after an early-in-life viral infection in a mouse model of multiple sclerosis (MS). The research “Brain-resident memory T cells generated early in life…

The loss of immune B-cells, and the resulting changes in the profile of immune T-cells, is a major mechanism of action for the beneficial effects seen with ublituximab treatment in multiple sclerosis (MS) patients, a study suggests. B-cells are a type of immune cell best known for producing…

Aubagio (teriflunomide), an approved medicine for relapsing forms of multiple sclerosis (MS), specifically targets highly metabolic and more autoreactive T-cells, analysis of the Phase 3 TERI-DYNAMIC clinical trial data shows. The findings, contrary to expectations, support a selective effect of Aubagio on different T-cell populations. The study “Teriflunomide treatment for multiple sclerosis modulates T cell mitochondrial respiration with affinity-dependent effects” was published in the Science Translational Medicine journal. In MS, immune cells, or lymphocytes known as T-cells, attack and destroy myelin, the fat-rich substance that wraps around nerve fibers (axons). Myelin loss creates lesions that affect nerves of the brain and spinal cord. Previous evidence suggested that T-cells, depending on their active or resting state, rely on specific ways of energy production or metabolism. Aubagio, marketed by Sanofi Genzyme, is a well-known inhibitor of a mitochondrial enzyme called dihydroorotate dehydrogenase (DHODH), that is crucial for the activity of T-cells. However, how Aubagio selectively targets the autoreactive T-cells is poorly understood. To shed light on this matter, an international group of researchers used data from the TERI-DYNAMIC clinical trial that tested Aubagio in patients with relapsing form of MS to better understand how the therapy inhibited the patients' self-immune responses. The Phase 3, open-label TERI-DYNAMIC trial (NCT01863888) included 70 patients from Belgium, Germany, and The Netherlands, aged 18 to 56. Participants received Aubagio as a 14 milligram (mg) once-daily, oral dose, and researchers assessed the changes in immune cells' profile up to 24 weeks. Results showed that, contrary to what was expected, Aubagio was not generally decreasing T-cell levels in treated patients. Instead, it significantly reduced a particular subset of T-cells, called "Th1 helper cells." Moreover, researchers found that the diversity of T-cell receptors — the surface proteins that can recognize a particular antigen (a protein that can elicit an immune response) — making T-cells specific to a certain target was reduced in MS patients after treatment with Aubagio. These findings suggested that some T-cells were particularly susceptible to Aubagio. Using a mouse model for MS, the experimental autoimmune encephalomyelitis (EAE) model, researchers showed that the CD4+ T-cells (helper T-cells) and CD8+ T-cells, those that reacted most strongly against self-antigens, were the most sensitive to DHODH inhibition by Aubagio. Moreover, researchers saw that Aubagio was not affecting the production of pro-inflammatory molecules — called cytokines — at the cell level, but their overall decrease probably was due to the reduction in T-cell numbers. In line with these findings, CD4+ T-cells that produced the cytokine interferon gamma were significantly reduced with Aubagio treatment, whereas CD4+ T-cells that produced interleukin 17A were unchanged. This suggests that Aubagio is able to interfere with specific sub-types of immune cells. When the team compared the metabolic profile of T-cells from healthy subjects with that from patients with relapsing-remitting MS (RRMS) in both remission and in relapse phases, they found that the metabolism of T-cells from the last group was significantly altered, and thus targetable. Altogether, the results suggested that T-cells with a high-affinity to self-antigens are more susceptible to inhibition of the DHODH enzyme by Aubagio. “Therapeutic targeting of metabolic alterations might represent an attractive concept in MS, and might represent an as yet unrecognized key mechanism of teriflunomide-mediated immune modulation in this disease,” the researchers concluded.

Stress-induced changes in gut bacteria, or gut microbiota, may play a significant part in the possible link between exposure to stress and the risk of autoimmune disorders such as multiple sclerosis (MS), a mouse research study says. In the study “…

Early, positive safety results from a Phase 1 trial testing a potential immunotherapy, ATA188, in people with progressive multiple sclerosis will be detailed at the 5th Congress of the European Academy of Neurology (EAN) late next month, its developer, Atara Biotherapeutics, announced. ATA188 is an investigational and “off-the-shelf”…

Reactivation of ancient viruses incorporated into the human genome in the course of evolution may be involved in the acute inflammatory response that is characteristic of multiple sclerosis (MS), a study says. The findings of the study, “Expression of endogenous retroviruses reflects increased usage of atypical enhancers in…

Treatment with Mayzent (siponomod) may reduce myelin deterioration by lessening the accumulation of immune cells in brain meninges, and preventing the migration of pro-inflammatory lymphocytes into the brain, according to a study in a mouse model of multiple sclerosis (MS). The research, “A Mouse Model of…

An active form of vitamin D can modulate the activity of immune cells and prevent autoimmune reactions known to be involved in several human diseases such as multiple sclerosis (MS). A study with that finding, led by researchers from The University of Edinburgh in Scotland, reveals a new layer…

Treating multiple sclerosis with Tecfidera induces specific genetic alterations that may reduce the levels of immune T-cells targeting the central nervous system, researchers report. Environmental stimuli may induce epigenetic changes in cells — meaning not alterations in the genes themselves, but changes in gene expression (the process by which information in a gene is synthesized to create a working product, like a protein). Epigenetic changes may induce MS development, as these alterations can cause T-cells to attack the central nervous system. One type of epigenetic change is DNA demethylation, the removal of methyl chemical groups, in which molecules involved in metabolism (such as fumarate) interact with enzymes known as DNA demethylases. This process in key for T-cell activation, function and memory, suggesting that it could be an immunomodulatory target. Fumaric acid esters were shown to be effective in MS clinical trials, leading to the approval of Tecfidera (by Biogen) for people with relapsing-remitting forms of the disease. However, their complete mechanism of action remains unclear. Aiming to address this gap, scientists at the Advanced Science Research Center (ASRC) at The Graduate Center of The City University of New York and the Icahn School of Medicine at Mount Sinai, recruited 98 MS patients, either previously untreated (47 people, mean age of 38.4), treated with Tecfidera (35 people, mean age of 42.3), or treated with glatiramer acetate (16 patients, mean age of 43.4) — marketed as Copaxone by Teva Pharmaceuticals, with generic forms by Sandoz (as Glatopa) and by Mylan. All patients had stable disease for at least three months, but disease duration was shortest in untreated patients — 40.4 months vs. 130 months in those given Tecfidera, and 100 months in patients using glatiramer acetate. Blood samples were collected from each participant to assess epigenetic changes in T-cells expressing the cell surface marker CD4. MS patients typically have an activated form of these cells in their blood and cerebrospinal fluid, the liquid surrounding the brain and spinal cord. Results revealed that, compared to the other two groups, treatment with Tecfidera was associated with a lower percentage of T-cells containing the CD3, CD4, and CD8 markers, as well as lower levels of subsets of T-cells expressing the CCR4 and CCR6 receptors, which are critical to T-cell migration to the gut, brain, and skin. Treatment with glatiramer acetate resulted in significantly milder alterations in T-cell percentages compared to no treatment. Researchers then found that FAEs induce excessive methylation — the addition of methyl groups — in T-cells containing CD4, compared to glatiramer acetate. Specifically, this overmethylation was observed in a micro-RNA — tiny RNA molecules than control gene expression — known as miR-21, key for the differentiation of a subset of T-cells called T helper-17 (Th17) cells and for CCR6 expression in MS mouse models. These Th17 cells are critical in tissue inflammation and destruction, and have been implicated in MS. The epigenetic effects of FAEs were subsequently validated by comparing pre- to post-treatment with Tecfidera in seven patients. In turn, in vitro (lab dish) experiments showed that FAEs act specifically on the activation of naïve T-cells — those able to respond to new pathogens to the immune system — containing the CD4 or the CD8 markers. Of note, patients with MS have shown increased miR-21 levels, particularly during acute relapses. As such, the team hypothesized that its hypermethylation by FAEs could contribute to remission and the prevention of relapses in this patient population. These results "suggest that the metabolic-epigenetic interplay in T-cells could be harnessed for therapeutic purposes," the researchers wrote, and that the immunomodulatory effect of FAEs in MS is due at least in part to the epigenetic regulation of T-cells. The researchers believe that their findings have a broader implication, beyond MS. "Our findings about therapeutically active metabolites have implications for the treatment of not only multiple sclerosis but also other autoimmune diseases, such as psoriasis and inflammatory bowel disease, which involve the same type of T-cells," Achilles Ntranos, the study’s lead author, said in a press release. "Understanding the epigenetic effect of metabolites on the immune system will help us develop several novel strategies for the treatment of autoimmune diseases, which could help patients and physicians achieve better clinical outcomes," Ntranos added. Patrizia Casaccia, the study’s senior author, concluded: "It may one day be possible to target and suppress production of the specific brain-homing T-cells that play a role in the development of MS."

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 findings suggest that Satb1 may be a therapeutic target for autoimmune diseases like MS. The research article, “Satb1 regulates the effector program of encephalitogenic tissue Th17 cells in chronic inflammation,” was published in the journal Nature Communications. Immune cells called T-helper 17 (Th17) cells play a range of roles in immunity, including protecting against infecting pathogens — 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's 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.  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. “Together, 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,” 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.

Treatment with a single dose of Ocrevus (ocrelizumab) depleted a subset of immune T-cells within two weeks in patients with relapsing multiple sclerosis (MS) or primary progressive MS (PPMS), according to a study. The study, “Ocrelizumab Depletes CD20+ T Cells in Multiple Sclerosis Patients,” was published in the journal Cells. Autoreactive immune T-cells, which attack the body’s own tissues, have been regarded as the primary mediator of MS; however, this view has been challenged by the effectiveness of therapies targeting immune B-cells that contain the CD20 cell surface protein in reducing disease activity. One such therapy is Genentech’s Ocrevus, an anti-CD20 monoclonal antibody, which was first approved in the U.S. in 2017 for patients with relapsing MS or PPMS. Because CD20 is mainly expressed by B-cell precursors and mature B-cells, Ocrevus is often considered to selectively deplete CD20-containing B-cells. However, CD20 is also expressed by highly activated T-cells with the CD3 protein marker, characterized by the increased production of proinflammatory molecules, or cytokines. These T-cells are found in the blood, cerebrospinal fluid — the liquid surrounding the brain and spinal cord — and chronic brain lesions of MS patients, and show an elevated expression of the CD8 and CD45 markers. Off-label use of rituximab (marketed as Rituxan in the U.S. and MabThera in Europe), a lymphoma and rheumatoid arthritis treatment that also targets CD20, has been associated with the depletion of CD20-containing T-cells in MS patients. Therefore, targeting this T-cell subtype has been hypothesized as an additional mechanism for rituximab’s clinical effectiveness. However, scientists did not know whether Ocrevus, which is different from rituximab in terms of CD20 binding and cell toxicity, also depletes CD20-positive T-cells. To address this unknown, a team from Hannover Medical School in Germany analyzed blood samples of MS patients through a technique called multicolor flow cytometry prior to the first dose of Ocrevus and after two weeks, immediately before the second dose. They intended to evaluate the characteristics of the patients’ peripheral blood mononuclear cells, which include T-cells, B-cells, monocytes, and macrophages. A total of 21 patients (13 women) were included, with a median age of 43 years (range 22-65 years). Of the participants, 17 had the relapsing form of the disease for a median of 14.6 years, while four had PPMS for a median of 5.6 years. The analysis found T-cells containing CD20 and CD3 in all patients. These cells accounted for 2.4% of all CD45-expressing lymphocytes — white blood cells that include T- and B-cells — and for a significant proportion (18.4%) of all CD20 cells. Evaluation of the cells’ fluorescence intensity revealed that CD20 levels were significantly lower on T-cells than on B-cells also expressing this marker. Treatment with one dose of Ocrevus substantially lowered the levels of CD20-positive T- and B-cells within two weeks, reflected by a frequency of 0.04% and an absolute cell count decrease from 224.9 to 0.57/microliter. “Our results demonstrate that treatment with [Ocrevus] does not exclusively target B-cells, but also CD20+ T-cells, which account for a substantial amount of CD20-expressing cells,” the researchers wrote. “These findings suggest that CD20+ T-cells might play a pivotal role in the pathogenesis of MS, and we speculate that depletion of CD3+CD20+ cells by anti-CD20 monoclonal antibodies might contribute to the efficacy of anti-CD20 therapy,” they added. However, they also emphasized that the findings need to be confirmed in studies with larger groups of MS patients.

An altered metabolism and signaling is associated with the ability of a subset of immune T helper 17 (Th17) cells to induce neuroinflammation, according to a new study of mice. The findings may lead to new treatments for multiple sclerosis (MS) and other chronic inflammatory diseases, the scientists said.

Treatment with autologous hematopoietic stem cell transplant (aHSCT) led to a sustained decrease in disability and almost no clinical relapses in patients with relapsing-remitting multiple sclerosis (RRMS) who had failed to respond to prior immunosuppressive therapies, an Australian Phase 2 trial shows. Trial findings were published in the study, “Prospective phase…

Aspirin, administered orally at low doses, was sufficient to suppress multiple sclerosis (MS) symptoms in a mouse model of relapsing-remitting MS (RRMS) and chronic MS, a study reports. The clinical benefits of aspirin were linked to an increase in the number of regulatory T-cells, those responsible for shutting…

Homotaurine, a compound proven safe for humans in long-term clinical trials, has eased autoimmune responses, brain inflammation, and multiple sclerosis-like symptoms in a mouse model of the disease, a study has found. The findings represent proof-of-principle evidence that homotaurine may represent a new potential class…

Atara Biotherapeutics’ investigational ATA190, a cell therapy that wipes out immune B-cells infected with the Epstein-Barr virus (EBV), led to neurological improvements and reduced symptoms in patients with primary and secondary progressive multiple sclerosis (MS), a Phase 1 trial shows. The trial results were published in the Journal…

Multiple sclerosis (MS) treatment Tecfidera (dimethyl fumarate) binds to a specific amino acid in key enzymes to inhibit their activity, according to a study that sheds more light on this therapy’s little-known mechanism of action. This newly identified regulatory mechanism may lead to the discovery of new compounds…

Stanford Researchers Open Medical Cannabis Company with Oral Therapy for MS Pain, Spasticity as Initial Goal Let’s be clear up front. There’s no indication that you’ll be able to buy a cannabis pill from this company anytime soon — or ever. The company’s website says that testing…

Infection with the most common member of the herpes virus family, called HHV-6, may pass unnoticed and without symptoms, but the very act of being infected significantly accelerated the development and progression of a multiple sclerosis-like disease in nonhuman primates, a study reports. Its findings support the role of viral infection in…

An enzyme produced by bacteria in the gut was seen to activate immune cells linked to the development and progression of multiple sclerosis, a finding that may pave the way for a vaccine that might alter autoimmune mechanisms involved in MS. The study, “…

A person’s genes influence the development of multiple sclerosis (MS), but so does the environment — both that in which an MS patient lives, and that which a patient creates through diet and other lifestyle choices, researchers said in a Thursday session at the 34th congress of the European…

Vitamin D may increase the therapeutic benefits of glucocorticosteroids (GCs) for multiple sclerosis (MS) through a protein complex called mTORc1, according to a study in a mouse model and in cells from MS patients. The study, “Vitamin D augments glucocorticosteroid efficacy via inhibition of mTORc1,” was presented…

Treatment with Rapacan (rapamycin) decreased the size and volume of brain lesions in patients with multiple sclerosis (MS), an Iranian study reports. The study, “Promising effect of rapamycin on multiple sclerosis,” was published in the journal Multiple Sclerosis and Related Disorders. Rapamycin, or sirolimus, is an immunosuppressive…

Lymphatic vessels, the “roads” that work to clear waste material from the brain, can also carry messages that direct immune system attacks against myelin, promoting the onset of multiple sclerosis (MS), new study shows. While the identity of these messages remains unknown, the findings suggest that blocking these signals could…

How B-cells Work to Promote T-cell Attacks on Myelin That Lead to MS Detailed in Study I keep a close eye on reports about B-cells and T-cells because they’re the targets of Lemtrada, which is my current disease-modifying therapy. (The DMT Ocrevus targets B-cells alone). So, this…

B-cells in the immune system play an important role in the unfolding of inflammation and brain lesions in multiple sclerosis (MS), largely by how they influence the actions of another immune system cell, called T-cells, a new study reports. Its findings help explain why therapies…

Removing a specific microRNA molecule — miR-150 – eased disease severity, inflammation, and loss of myelin in a mouse model of multiple sclerosis (MS), researchers report. Their study, “Silencing miR-150 Ameliorates Experimental Autoimmune Encephalomyelitis,” was published in the journal Frontiers in Neuroscience. Micro RNAs (miRNAs) are…

Missouri Trial to Examine if Fasting Alters Gut Microbiome and Immune System of RRMS Patients in Helpful Ways The impact of various diets on multiple sclerosis (MS) has been studied, but this new study will look into whether fasting has an impact. The researchers at Washington University…

New research shows that overreactive and tissue-damaging T-cells can transition into regulatory T-cells that help to control the immune system’s response. These findings open the door to further understanding of the mechanism underlying this transition, knowledge that can help scientists in designing more effective, targeted immunotherapies for diseases like multiple…

A new fluorescent imaging strategy allows researchers to track T-cells and further understand their dynamics in vivo, giving them insight into what happens when these immune cells attack myelin in a mouse model of multiple sclerosis (MS). The new technology was reported in the study, “A timer for…