The Evolving Mechanisms of Action of Glatiramer Acetate

Glatiramer Acetate Modifies the Immune Profiles of Monocyte-Derived Dendritic Cells In Vitro Without Affecting Their Generation

Glatiramer acetate (GA) is the first-line therapy for relapsing-remitting multiple sclerosis (MS) and is increasingly demonstrating promising therapeutic benefits in a range of other conditions. Despite its extensive use, the precise pharmacological mechanism of GA remains unclear. In addition to T and B cells, dendritic cells (DCs) and monocytes play significant roles in the neuroinflammation associated with MS, positioning them as potential initial targets for GA. Here, we investigated GA's influence on the differentiation of human monocytes from healthy donors into monocyte-derived dendritic cells (moDCs) and assessed their activation status. Our results indicate that GA treatment does not hinder the differentiation of monocytes into moDCs or macrophages. Notably, we observed a significant increase in the expression of molecules required for antigen recognition, presentation, and co-stimulation in GA-treated moDCs. Conversely, there was a significant downregulation of CD1a, which is crucial for activating auto-aggressive T cells that respond to the lipid components of myelin. Furthermore, GA treatment resulted in an increased expression of CD68 on both CD14+CD16+ and CD14+CD16- monocyte subsets. These in vitro findings suggest that GA treatment does not impede the generation of moDCs under inflammatory conditions; however, it may modify their functional characteristics in potentially beneficial ways. This provides a basis for future clinical studies in MS patients to elucidate its precise mode of action.

A review on multiple sclerosis: Unravelling the complexities of pathogenesis, progression, mechanisms and therapeutic innovations

Multiple sclerosis (MS) is a chronic, inflammatory demyelinating disorder of the central nervous system (CNS) targeting myelinated axons. Pathogenesis of MS entails an intricate genetic, environmental, and immunological interaction. Dysregulation of immune response i.e. autoreactive T & B-Cells and macrophage infiltration into the CNS leads to inflammation, demyelination, and neurodegeneration. Disease progression of MS varies among individuals transitioning from one form of relapsing-remitting to secondary progressive MS (SPMS). Research advances have unfolded various molecular targets involved in MS from oxidative stress to blood-brain barrier (BBB) disruption. Different pathways are being targeted so far such as inflammatory and cytokine signaling pathways to overcome disease progression. Therapeutic innovations have significantly transformed the management of MS, especially the use of disease-modifying therapies (DMTs) to reduce relapse rates and control disease progression. Advancements in research, neuroprotective strategies, and remyelination strategies hold promising results in reversing CNS damage. Various mice models are being adopted for testing new entities in MS research.

Immune mechanisms and shared immune targets in neurodegenerative diseases

The immune system plays a major part in neurodegenerative diseases. In some, such as multiple sclerosis, it is the primary driver of the disease. In others, such as Alzheimer disease, amyotrophic lateral sclerosis and Parkinson disease, it has an amplifying role. Immunotherapeutic approaches that target the adaptive and innate immune systems are being explored for the treatment of almost all neurological diseases, and the targets and approaches are often common across diseases. Microglia are the primary immune cells in the brain that contribute to disease pathogenesis, and are consequently a common immune target for therapy. Other therapeutic approaches target components of the peripheral immune system, such as regulatory T cells and monocytes, which in turn act within the CNS. This Review considers in detail how microglia, monocytes and T cells contribute to the pathogenesis of multiple sclerosis, Alzheimer disease, amyotrophic lateral sclerosis and Parkinson disease, and their potential as shared therapeutic targets across these diseases. The microbiome is also highlighted as an emerging therapeutic target that indirectly modulates the immune system. Therapeutic approaches being developed to target immune function in neurodegenerative diseases are discussed, highlighting how immune-based approaches developed to treat one disease could be applicable to multiple other neurological diseases.

Sportizumab - Multimodal progressive exercise over 10 weeks decreases Th17 frequency and CD49d expression on CD8+ T cells in relapsing-remitting multiple sclerosis: A randomized controlled trial

BACKGROUND

Multiple Sclerosis (MS) represents a neuroinflammatory autoimmune disease characterized by the predominance of circulating T cell subsets with proinflammatory characteristics and increased central nervous system (CNS)-homing potential. Substantial evidence confirms various beneficial effects of chronic exercise interventions in MS, but it is unknown how long-term multi-modal intense exercise affects MS-associated lymphocytes that are commonly targeted by medication in persons with relapsing remitting MS (pwRRMS).

METHODS

A total of 45 participants with defined RRMS were randomized to either the exercise (n = 22) or passive waitlist-control group (n = 23). A 10-week intervention consisting of progressive resistance and strength-endurance exercises was applied (3x/week à 60 min). Blood was drawn before (T1) and after (T2) the intervention period. Flow cytometry was used for phenotyping lymphocyte subsets.

RESULTS

Relative protein expression of CD49d within CD8+ T cells, quantified via mean fluorescence intensity (MFI), is significantly associated with the Expanded Disability Status Scale (p = 0.007, r = 0.440), decreased in the exercise group (p = 0.001) only, and was significantly lower in the exercise compared to the control group at T2 (p < 0.001). T helper (Th) 17 cell frequency decreased only in the exercise group (p < 0.001). CD8+CD20+ T cell frequency was significantly lower in the exercise compared to the control group at T2 (p = 0.003), without showing significant time effects.

CONCLUSION

The 10-week multimodal exercise intervention mainly affected circulating T cells harboring a pathophysiological phenotype in MS. The findings of a decreased frequency of pathogenic Th17 cells and the reduced CNS-homing potential of CD8+ T cells, indicated by reduced CD49d MFI, substantiate the positive effects of exercise on cellular biomarkers involved in disease activity and progression in MS. To confirm exercise-mediated beneficial effects on both disease domains, clinical endpoints (i.e., relapse rate, lesion formation, EDSS score) should be assessed together with these cellular and molecular markers in studies with a larger sample size and a duration of six to twelve months or longer.

Intralesional injection of CpG ODNs complexed with glatiramer acetate mitigates systemic cytokine toxicities and synergistically advances checkpoint blockade efficacy

PD-L1/PD-1 checkpoint inhibitors (CPIs) are mainstream agents for cancer immunotherapy, but the prognosis is unsatisfactory in solid tumor patients lacking preexisting T-cell reactivity. Adjunct therapy strategies including the intratumoral administration of immunostimulants aim to address this limitation. CpG oligodeoxynucleotides (ODNs), TLR9 agonists that can potentiate adaptive immunity, have been widely investigated to tackle PD-L1/PD-1 resistance, but clinical success has been hindered by inconsistent efficacy and immune-related toxicities caused by systemic exposure. Here, we utilized glatiramer acetate (GA), the FDA-approved, lysine-rich polypeptides to complex CpG into polycationic nanoparticles (R4B) and investigated the safety and antitumor efficacy of CpG ODNs in the murine CT26 colorectal carcinoma model. In a maximum tolerated dose study, repetitive R4B treatment displayed comparable antitumor efficacy to CpG alone treatment within a dose range from 15 µg to 150 µg while significantly attenuating systemic proinflammatory cytokine IL-6 release. A pharmacokinetic and biodistribution analysis confirmed that R4B localized and gradually released CpG around the lesions within 96 h while 'naked' CpG quickly diffused from the injection site. Genome-wide transcriptome analysis validated that R4B treatment activated prominent TLR9-driven immune system responses in both lesions and spleens. In a CT26 multiple tumor model, intratumoral administration of R4B generated systemic immune efficacy, evidenced by an abscopal effect on untreated tumors. Notably, R4B treatment accomplished these effects with mitigated systemic proinflammatory cytokines when compared with CpG alone. We further discovered that combining R4B with anti-PD-1 treatment led to the most pronounced effects on tumor growth and longest benefits to survival time. Our investigation into possible mechanisms underlying this phenomenon included increased recruitment of cytotoxic CD8+ T cells and natural killer (NK) cells to the tumor microenvironments and the reversal of PD-L1/PD-1 axis inhibition. In summary, these results warrant further investigation for safely improving clinical responses in CPI-resistant solid tumor patients with localized CpG ODN therapy.

Star-Shaped Glatiramer Acetate Mitigates Pulmonary Dysfunction and Brain Neurodegeneration in a Murine Model of Cryptococcus-Associated IRIS

Cryptococcal-associated immune reconstitution inflammatory syndrome (C-IRIS) is a clinical worsening or new presentation of cryptococcal disease following the initiation of antiretroviral therapy. C-IRIS is primarily driven by an influx of pathological CD4 + T cells, which triggers a hyperinflammatory response. The murine model of C-IRIS is a way to study the disease in mice and understand how the immune system triggers life-threatening outcomes in patients. We previously developed a murine C-IRIS model and demonstrated that C-IRIS is triggered by pathological CD4 + T cells, particularly Th1 cells, in the brain, which triggers neurodegeneration and pulmonary dysfunction. Using this unique mouse model, we tested the therapeutic effect of a star-shaped glatiramer acetate (sGA), which is a more effective isomeric form than linear GA. Here, we observed that sGA suppresses Th1 differentiation in the lung tissues, reducing CD4 + T cell and Th1 cell count. It also reduced microglia populations in the brain. Together, these changes improved respiratory dysfunction caused by C-IRIS, lowered mortality rate, and reduced brain neurodegeneration. These findings suggest that sGA could be an effective therapeutic strategy for managing C-IRIS.

Astrocytes and microglia in multiple sclerosis and neuromyelitis optica

Multiple sclerosis and neuromyelitis optica are autoimmune neurodegenerative diseases primarily targeting myelin sheath and neuroglia. In multiple sclerosis, autoantibodies destroy oligodendrocytes and myelin, which underlies primary neurologic symptoms. Focal damage to myelin triggers reactive astrogliosis and microgliosis, which contribute to and to a large extent define the disease progression. In neuromyelitis optica, autoantibodies against water channel aquaporin 4 (AQP4), which are localized at astrocytic endfeet mediate damage of the glia limitans thus facilitating infiltration of blood-borne molecules and cells that propagate the damage to nerves and neurons. This primary astrocytopathy recruits microglia, which contribute to the neuroinflammatory response. Neuroglial cells therefore are potential targets for cell-specific therapies.

Multiple sclerosis: a narrative overview of current pharmacotherapies and emerging treatment prospects

Multiple sclerosis (MS) is a chronic autoimmune disease characterized by pathological processes of demyelination, subsequent axonal loss, and neurodegeneration within the central nervous system. Despite the availability of numerous disease-modifying therapies that effectively manage this condition, there is an emerging need to identify novel therapeutic targets, particularly for progressive forms of MS. Based on contemporary insights into disease pathophysiology, ongoing efforts are directed toward developing innovative treatment modalities. Primarily, monoclonal antibodies have been extensively investigated for their efficacy in influencing specific pathological pathways not yet targeted. Emerging approaches emphasizing cellular mechanisms, such as chimeric antigen receptor T cell therapy targeting immunological cells, are attracting increasing interest. The evolving understanding of microglia and the involvement of ferroptotic mechanisms in MS pathogenesis presents further avenues for targeted therapies. Moreover, innovative treatment strategies extend beyond conventional approaches to encompass interventions that target alterations in microbiota composition and dietary modifications. These adjunctive therapies hold promise as complementary methods for the holistic management of MS. This narrative review aims to summarize current therapies and outline potential treatment methods for individuals with MS.

The contribution of tumor necrosis factor to multiple sclerosis: a possible role in progression independent of relapse?

Tumor necrosis factor (TNF) is a pleiotropic cytokine regulating many physiological and pathological immune-mediated processes. Specifically, it has been recognized as an essential pro-inflammatory cytokine implicated in multiple sclerosis (MS) pathogenesis and progression. MS is a chronic immune-mediated disease of the central nervous system, characterized by multifocal acute and chronic inflammatory demyelination in white and grey matter, along with neuroaxonal loss. A recent concept in the field of MS research is disability resulting from Progression Independent of Relapse Activity (PIRA). PIRA recognizes that disability accumulation since the early phase of the disease can occur independently of relapse activity overcoming the traditional dualistic view of MS as either a relapsing-inflammatory or a progressive-neurodegenerative disease. Several studies have demonstrated an upregulation in TNF expression in both acute and chronic active MS brain lesions. Additionally, elevated TNF levels have been observed in the serum and cerebrospinal fluid of MS patients. TNF appears to play a significant role in maintaining chronic intrathecal inflammation, promoting axonal damage neurodegeneration, and consequently contributing to disease progression and disability accumulation. In summary, this review highlights the current understanding of TNF and its receptors in MS progression, specifically focusing on the relatively unexplored PIRA condition. Further research in this area holds promise for potential therapeutic interventions targeting TNF to mitigate disability in MS patients.

Can Glatiramer Acetate Prevent Cognitive Impairment by Modulating Oxidative Stress in Patients with Multiple Sclerosis?

Multiple sclerosis (MS) is an autoimmune disease characterized by demyelination and neuroinflammation, often accompanied by cognitive impairment. This study aims (1) to investigate the potential of glatiramer acetate (GA) as a therapy for preventing cognitive decline in patients with MS (pwMS) by modulating oxidative stress (OS) and (2) to seek out the differences in cognition between pwMS in a cohort exhibiting good clinical evolution and control subjects (CS). An exploratory, prospective, multicentre, cross-sectional case-control study was conducted, involving three groups at a 1:1:1 ratio-41 GA-treated pwMS, 42 untreated pwMS, and 42 CS. The participants performed a neuropsychological battery and underwent venepuncture for blood sampling. The inclusion criteria required an Expanded Disability Status Scale score of ≤3.0 and a minimum of 5 years of MS disease. Concerning cognition, the CS had a better performance than the pwMS (p = <0.0001), and between those treated and untreated with GA, no statistically significant differences were found. Regarding oxidation, no statistically significant differences were detected. Upon categorizing the pwMS into cognitively impaired and cognitively preserved groups, the lactate was elevated in the pwMS with cognitive preservation (p = 0.038). The pwMS exhibited a worse cognitive performance than the CS. The pwMS treated with GA did not show an improvement in oxidation. Lactate emerged as a potential biomarker for cognitive preservation.

Antimicrobial peptide glatiramer acetate targets Pseudomonas aeruginosa lipopolysaccharides to breach membranes without altering lipopolysaccharide modification

Antimicrobial peptides (AMPs) are key components of innate immunity across all domains of life. Natural and synthetic AMPs are receiving renewed attention in efforts to combat the antimicrobial resistance (AMR) crisis and the loss of antibiotic efficacy. The gram-negative pathogen Pseudomonas aeruginosa is one of the most concerning infecting bacteria in AMR, particularly in people with cystic fibrosis (CF) where respiratory infections are difficult to eradicate and associated with increased morbidity and mortality. Cationic AMPs exploit the negatively charged lipopolysaccharides (LPS) on P. aeruginosa to bind and disrupt bacterial membrane(s), causing lethal damage. P. aeruginosa modifies its LPS to evade AMP killing. Free-LPS is also a component of CF sputum and feeds pro-inflammatory cycles. Glatiramer acetate (GA) is a random peptide co-polymer-of glycine, lysine, alanine, tyrosine-used as a drug in treatment of multiple sclerosis (MS); we have previously shown GA to be an AMP which synergises with tobramycin against CF P. aeruginosa, functioning via bacterial membrane disruption. Here, we demonstrate GA's direct binding and sequestration/neutralisation of P. aeruginosa LPS, in keeping with GA's ability to disrupt the outer membrane. At CF-relevant LPS concentrations, however, membrane disruption by GA was not strongly inhibited. Furthermore, exposure to GA did not result in increased Lipid A modification of LPS or in increased gene expression of systems involved in AMP sensing and LPS modification. Therefore, despite the electrostatic targeting of LPS by GA as part of its activity, P. aeruginosa does not demonstrate LPS modification in its defence.

Catalytic Antibodies May Contribute to Demyelination in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Here we report preliminary data demonstrating that some patients with myalgic encephalomyelitis/chronic fatiguesyndrome (ME/CFS) may have catalytic autoantibodies that cause the breakdown of myelin basic protein (MBP). We propose that these MBP-degradative antibodies are important to the pathophysiology of ME/CFS, particularly in the occurrence of white matter disease/demyelination. This is supported by magnetic resonance imagining studies that show these findings in patients with ME/CFS and could explain symptoms of nerve pain and muscle weakness. In this work, we performed a series of experiments on patient plasma samples where we isolated and characterized substrate-specific antibodies that digest MBP. We also tested glatiramer acetate (copaxone), an FDA approved immunomodulator to treat multiple sclerosis, and found that it inhibits ME/CFS antibody digestion of MBP. Furthermore, we found that aprotinin, which is a specific serine protease inhibitor, specifically prevents breakdown of MBP while the other classes of protease inhibitors had no effect. This coincides with the published literature describing catalytic antibodies as having serine protease-like activity. Postpandemic research has also provided several reports of demyelination in COVID-19. Because COVID-19 has been described as a trigger for ME/CFS, demyelination could play a bigger role in patient symptoms for those recently diagnosed with ME/CFS. Therefore, by studying proteolytic antibodies in ME/CFS, their target substrates, and inhibitors, a new mechanism of action could lead to better treatment and a possible cure for the disease.

Use of Cells, Supplements, and Peptides as Therapeutic Strategies for Modulating Inflammation after Spinal Cord Injury: An Update

Spinal cord injury is a traumatic lesion that causes a catastrophic condition in patients, resulting in neuronal deficit and loss of motor and sensory function. That loss is caused by secondary injury events following mechanical damage, which results in cell death. One of the most important events is inflammation, which activates molecules like proinflammatory cytokines (IL-1β, IFN-γ, and TNF-α) that provoke a toxic environment, inhibiting axonal growth and exacerbating CNS damage. As there is no effective treatment, one of the developed therapies is neuroprotection of the tissue to preserve healthy tissue. Among the strategies that have been developed are the use of cell therapy, the use of peptides, and molecules or supplements that have been shown to favor an anti-inflammatory environment that helps to preserve tissue and cells at the site of injury, thus favoring axonal growth and improved locomotor function. In this review, we will explain some of these strategies used in different animal models of spinal cord injury, their activity as modulators of the immune system, and the benefits they have shown.

Effect of Disease-Modifying Therapies on COVID-19 Vaccination Efficacy in Multiple Sclerosis Patients: A Comprehensive Review

According to current knowledge, the etiopathogenesis of multiple sclerosis (MS) is complex, involving genetic background as well as several environmental factors that result in dysimmunity in the central nervous system (CNS). MS is an immune-mediated, inflammatory neurological disease affecting the CNS. As part of its attack on the axons of the CNS, MS witnesses varying degrees of myelin and axonal loss. A total of about 20 disease-modifying therapies (DMTs) are available today that, both in clinical trials and in real-world studies, reduce disease activity, such as relapses, magnetic resonance imaging lesions, and disability accumulation. Currently, the world is facing an outbreak of the new coronavirus disease 2019 (COVID-19), which originated in Wuhan, Hubei Province, China, in December 2019 and spread rapidly around the globe. Viral infections play an important role in triggering and maintaining neuroinflammation through direct and indirect mechanisms. There is an old association between MS and viral infections. In the context of MS-related chronic inflammatory damage within the CNS, there has been concern regarding COVID-19 worsening neurological damage. A high rate of disability and increased susceptibility to infection have made MS patients particularly vulnerable. In addition, DMTs have been a concern during the pandemic since many DMTs have immunosuppressive properties. In this article, we discuss the impact of DMTs on COVID-19 risks and the effect of DMTs on COVID-19 vaccination efficacy and outcome in MS patients.

Inconsistent Effects of Glatiramer Acetate Treatment in the 5xFAD Mouse Model of Alzheimer's Disease

Alzheimer's disease (AD) is a chronic neurodegenerative disorder that involves strong inflammatory components. Aberrant and prolonged inflammation in the CNS is thought to contribute to the development of the pathology. The use of single cytokine approaches to curb or leverage inflammatory mechanisms for disease modifying benefit has often resulted in conflicting data. Furthermore, these treatments were usually delivered locally into the CNS parenchyma, complicating translational efforts. To overcome these hurdles, we tested the use of glatiramer acetate (GA) in reducing amyloid beta (Aβ) plaque pathology in the 5xFAD model of AD. GA immunizations were begun at the ages of 2.5 months, 5.5 months, and 8.5 months, and GA was delivered weekly for 8 weeks. While previous data describe potential benefits of GA immunization in decreasing Aβ levels in murine models of AD, we found modest decreases in Aβ levels if given during the development of pathology but, surprisingly, found increased Aβ levels if GA was administered at later stages. The impact of GA treatment was only significant for female mice. Furthermore, we observed no changes between microglial uptake of plaque, CD11c immunopositivity of microglia, or levels of TMEM119 and P2Ry12 on microglia. Overall, these data warrant exercising caution when aiming to repurpose GA for AD.

Multiple sclerosis and glatiramer acetate: Risk factors for central retinal vein occlusion?

Multiple sclerosis may present an increased risk for venous thromboembolism. Ophthalmological symptoms include loss of vision, visual field loss, changes in color vision, diplopia and nystagmus. First-line treatments for multiple sclerosis are beta-interferon, glatiramer acetate, dimethyl fumarate and teriflunomide. To the best of our knowledge, no ophthalmologic side effects have been reported with glatiramer acetate. We present a woman with multiple sclerosis on glatiramer acetate therapy with a central retinal vein occlusion in the absence of other risk factors.

Risk of cervical pre-cancer and cancer in women with multiple sclerosis exposed to high efficacy disease modifying therapies

There is a growing need to better understand the risk of malignancy in the multiple sclerosis (MS) population, particularly given the relatively recent and widespread introduction of immunomodulating disease modifying therapies (DMTs). Multiple sclerosis disproportionately affects women, and the risk of gynecological malignancies, specifically cervical pre-cancer and cancer, are of particular concern. The causal relationship between persistent human papillomavirus (HPV) infection and cervical cancer has been definitively established. To date, there is limited data on the effect of MS DMTs on the risk of persistent HPV infection and subsequent progression to cervical pre-cancer and cancer. This review evaluates the risk of cervical pre-cancer and cancer in women with MS, including the risk conferred by DMTs. We examine additional factors, specific to the MS population, that alter the risk of developing cervical cancer including participation in HPV vaccination and cervical screening programs.

Prophylactic Glatiramer Acetate Treatment Positively Attenuates Spontaneous Opticospinal Encephalomyelitis

Background: Glatiramer acetate (GA) is a well-established treatment option for patients with clinically isolated syndrome and relapsing-remitting multiple sclerosis (MS) with few side effects. The double transgenic mouse model spontaneous opticospinal encephalomyelitis (OSE), based on recombinant myelin oligodendrocyte glycoprotein_35-55 reactive T and B cells, mimicks features of chronic inflammation and degeneration in MS and related disorders. Here, we investigated the effects of prophylactic GA treatment on the clinical course, histological alterations and peripheral immune cells in OSE. Objective: To investigate the effects of prophylactic glatiramer acetate (GA) treatment in a mouse model of spontaneous opticospinal encephalomyelitis (OSE). Methods: OSE mice with a postnatal age of 21 to 28 days without signs of encephalomyelitis were treated once daily either with 150 µg GA or vehicle intraperitoneally (i. p.). The animals were scored daily regarding clinical signs and weight. The animals were sacrificed after 30 days of treatment or after having reached a score of 7.0 due to animal care guidelines. We performed immunohistochemistry of spinal cord sections and flow cytometry analysis of immune cells. Results: Preventive treatment with 150 µg GA i. p. once daily significantly reduced clinical disease progression with a mean score of 3.9 ± 1.0 compared to 6.2 ± 0.7 in control animals (p < 0.01) after 30 d in accordance with positive effects on weight (p < 0.001). The immunohistochemistry showed that general inflammation, demyelination or CD11c⁺ dendritic cell infiltration did not differ. There was, however, a modest reduction of the Iba1⁺ area (p < 0.05) and F4/80⁺ area upon GA treatment (p < 0.05). The immune cell composition of secondary lymphoid organs showed a trend towards an upregulation of regulatory T cells, which lacked significance. Conclusions: Preventive treatment with GA reduces disease progression in OSE in line with modest effects on microglia/macrophages. Due to the lack of established prophylactic treatment options for chronic autoimmune diseases with a high risk of disability, our study could provide valuable indications for translational medicine.

Safety and Monitoring of the Treatment with Disease-Modifying Therapies (DMTs) for Multiple Sclerosis (MS)

BACKGROUND

Disease-Modifying Therapies (DMTs) for Multiple Sclerosis (MS) are widely used given their proven efficacy in the relapsing form of the disease, while recently, Siponimod and Ocrelizumab have been approved for the progressive forms of the disease. Currently, 22 diseasemodifying drugs are approved by the FDA, while in 2012, only nine were present in the market. From March 2019 until August 2020, six new drugs were approved. This rapid development of new DMTs highlighted the need to update our knowledge about their short and long-term safety.

OBJECTIVE

This review summarizes the available safety data for all the Disease-Modifying Therapies for Multiple Sclerosis and presents the monitoring plan before and during the treatment.

METHODS

A literature search was conducted using PUBMED and COCHRANE databases. Key journals and abstracts from major annual meetings of Neurology, references of relevant reviews, and relative articles were also manually searched. We prioritized systematic reviews, large randomized controlled trials (RCTs), prospective cohort studies, and other observational studies. Special attention was paid to guidelines and papers focusing on the safety and monitoring of DMTs.

CONCLUSION

Data for oral (Sphingosine 1-phosphate (S1P) receptor modulators, Fumarates, Teriflunomide, Cladribine), injectables (Interferons, Glatiramer acetate, Ofatumumab), and infusion therapies (Natalizumab, Ocrelizumab, Alemtuzumab) are presented.

Autoreactive lymphocytes in multiple sclerosis: Pathogenesis and treatment target

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) characterized by destruction of the myelin sheath structure. The loss of myelin leads to damage of a neuron’s axon and cell body, which is identified as brain lesions on magnetic resonance image (MRI). The pathogenesis of MS remains largely unknown. However, immune mechanisms, especially those linked to the aberrant lymphocyte activity, are mainly responsible for neuronal damage. Th1 and Th17 populations of lymphocytes were primarily associated with MS pathogenesis. These lymphocytes are essential for differentiation of encephalitogenic CD8⁺ T cell and Th17 lymphocyte crossing the blood brain barrier and targeting myelin sheath in the CNS. B-lymphocytes could also contribute to MS pathogenesis by producing anti-myelin basic protein antibodies. In later studies, aberrant function of Treg and Th9 cells was identified as contributing to MS. This review summarizes the aberrant function and count of lymphocyte, and the contributions of these cell to the mechanisms of MS. Additionally, we have outlined the novel MS therapeutics aimed to amend the aberrant function or counts of these lymphocytes.

Treatment and Relapse Prevention of Typical and Atypical Optic Neuritis

Optic neuritis (ON) is an inflammatory condition involving the optic nerve. Several important typical and atypical ON variants are now recognized. Typical ON has a more favorable prognosis; it can be idiopathic or represent an early manifestation of demyelinating diseases, mostly multiple sclerosis (MS). The atypical spectrum includes entities such as antibody-driven ON associated with neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody disease (MOGAD), chronic/relapsing inflammatory optic neuropathy (CRION), and sarcoidosis-associated ON. Appropriate and timely diagnosis is essential to rapidly decide on the appropriate treatment, maximize visual recovery, and minimize recurrences. This review paper aims at presenting the currently available state-of-the-art treatment strategies for typical and atypical ON, both in the acute phase and in the long-term. Moreover, emerging therapeutic approaches and novel steps in the direction of achieving remyelination are discussed.

Thinking outside the box: non-canonical targets in multiple sclerosis

Multiple sclerosis (MS) is an immune-mediated disease of the central nervous system that causes demyelination, axonal degeneration and astrogliosis, resulting in progressive neurological disability. Fuelled by an evolving understanding of MS immunopathogenesis, the range of available immunotherapies for clinical use has expanded over the past two decades. However, MS remains an incurable disease and even targeted immunotherapies often fail to control insidious disease progression, indicating the need for new and exceptional therapeutic options beyond the established immunological landscape. In this Review, we highlight such non-canonical targets in preclinical MS research with a focus on five highly promising areas: oligodendrocytes; the blood-brain barrier; metabolites and cellular metabolism; the coagulation system; and tolerance induction. Recent findings in these areas may guide the field towards novel targets for future therapeutic approaches in MS.

Positive effect of immunomodulatory therapies on disease progression in Huntington's disease? Data from a real-world cohort

Background:

The role of neuroinflammation and autoimmune processes in neurodegenerative diseases is not fully understood. Activation of microglia with expression of proinflammatory cytokines supports the hypothesis that immune processes may play an important role in the pathophysiology of Huntington’s disease (HD) and thus, immunomodulating therapies might have potential neuroprotective properties. Until now, no disease-modifying therapy (DMT) is available for HD.

Objective:

The aim of this research was to characterize a cohort of patients suffering from both HD and autoimmune demyelinating diseases of the central nervous system (classified as G35-37 in ICD-10; ADD-CNS) in comparison to HD cases without ADD-CNS. In particular, we were interested to investigate potential modulating effects on disease manifestation and progression of HD over time of prescribed immunomodulating medications (DMT).

Methods:

We analyzed the course of HD regarding motoric, functional, and cognitive aspects, using longitudinal data of up to 2 years from the worldwide registry study ENROLL-HD. Additional cross-sectional data in the largest cohort worldwide of HD patients was analyzed using demographic and molecular genetic parameters. Data were analyzed using analysis of variance (ANOVA) for cross-sectional and repeated-measures ANOVA for longitudinal parameters in IBM SPSS Statistics V.27.

Results:

Within the ENROLL-HD database, we investigated N = 21,116 participants and identified n = 60 participants suffering from ADD-CNS. Molecular, genetic, and demographic data did not differ between groups. The subgroup of n = 32 participants with motor-manifest HD revealed better cognitive performance in five out of eight cognitive tests at baseline with less progression over time in two tests (all p < 0.05). Differentiation between DMT-treated and untreated patients revealed better cognitive and motor performance in the DMT group; those patients, however, tended to be younger. Pre-manifest HD patients simultaneously diagnosed with ADD-CNS (n = 12) showed lower functional scores and more decline over time when compared with other pre-manifest HD (p < 0.05).

Conclusion:

Patients suffering from motor-manifest HD and simultaneously from ADD-CNS have better cognitive capacities compared with other motor-manifest HD patients. Moreover, DMTs might have beneficial effects on progression of neurodegeneration including the motor phenotype. However, this effect might have been biased by younger age in DMT-treated patients. Pre-manifest HD patients showed more functional impairment as expected due to their additional ADD-CNS disease.

Thioctamer: a novel thioctic acid-glatiramer acetate nanoconjugate expedites wound healing in diabetic rats

The current work aims to design thioctic acid (TA) and glatiramer acetate (GA) nanoconjugate (thioctamer) loaded hydrogel formula as well as evaluation of thioctamer preclinical efficacy in expediting wound healing in a rat model of the diabetic wound. Thioctamer was prepared by conjugation of GA and TA in a 1:1 molar ratio. Particle size, zeta potential, and thermodynamic stability of the prepared thioctamer were assessed. Thioctamer was loaded in hydroxypropyl methylcellulose-based hydrogel and in vitro release study was investigated. The ability of thioctamer to enhance the process of wound healing in diabetic rats was investigated by assessing wound contraction and immunohistochemical assessment of the inflammation markers IL-6 and TNF-α. The results demonstrated that thioctamer showed particle size of 137 ± 21.4 nm, polydispersity index (PDI) of 0.235, and positive zeta potential value of 7.43 ± 4.95 mV. On day 7 of making a skin excision, diabetic rat wounds administered thioctamer preparation showed almost complete healing (95.6 ± 8.6%). Meanwhile, % of wound contraction in animals treated with TA or GA groups exhibited values amounting to 56.5 ± 5.8% and 62.6 ± 7.1%, respectively. Histological investigation showed that the highest healing rate was noted in the thioctamer group animals, as the surface of the wound was nearly fully protected by regenerated epithelium with keratinization, with few inflammatory cells noticed. Thioctamer significantly (p<.05) inhibited IL-6 and TNF-α expression as compared with sections obtained from the negative control, TA, GA, or positive control group animals on day 7. The evidence of the ability of thioctamer to significantly expedite wound healing in the diabetic rats is presented.

Glatiramer Acetate Immunomodulation: Evidence of Neuroprotection and Cognitive Preservation

Novel, neuroprotective uses of Copaxone (generic name: glatiramer acetate-GA) are being examined, primarily in neurological conditions involving cognitive decline. GA is a well-studied synthetic copolymer that is FDA-approved for immune-based treatment of relapsing remitting multiple sclerosis (RRMS). Clinical studies have explored the potential mechanism of action (MOA) and outcomes of GA immunization in patients. Furthermore, results from these and animal studies suggest that GA has a direct immunomodulatory effect on adaptive and innate immune cell phenotypes and responses. These MOAs have been postulated to have a common neuroprotective impact in several neuroinflammatory and neurodegenerative diseases. Notably, several clinical studies report that the use of GA mitigated MS-associated cognitive decline. Its propensity to ameliorate neuro-proinflammatory and degenerative processes ignites increased interest in potential alternate uses such as in age-related macular degeneration (AMD), amyotrophic lateral sclerosis (ALS), and Alzheimer's disease (AD). Preclinical studies are exploring less frequent subcutaneous administration of GA, such as once weekly or monthly or a single dosing regimen. Indeed, cognitive functions were found to be either preserved, reversed, or improved after the less frequent treatment regimens with GA in animal models of AD. In this systematic review, we examine the potential novel uses of GA across clinical and pre-clinical studies, with evidence for its beneficial impact on cognition. Future investigation in large-size, double-blind clinical trials is warranted to establish the impact of GA immunomodulation on neuroprotection and cognitive preservation in various neurological conditions.

Treatment Challenges in Multiple Sclerosis – A Continued Role for Glatiramer Acetate?

Earlier diagnosis, access to disease-modifying therapies (DMTs), and improved supportive care have favorably altered the disease course of multiple sclerosis (MS), leading to an improvement in long-term outcomes for people with MS (PwMS). This success has changed the medical characteristics of the population seen in MS clinics. Comorbidities and the accompanying polypharmacy, immune senescence, and the growing number of approved DMTs make selecting the optimal agent for an individual patient more challenging. Glatiramer acetate (GA), a moderately effective DMT, interacts only minimally with comorbidities, other medications, or immune senescence. We describe here several populations in which GA may represent a useful treatment option to overcome challenges due to advanced age or comorbidities (e.g., hepatic or renal disease, cancer). Further, we weigh GA's potential merits in other settings where PwMS and their neurologists must base treatment decisions on factors other than selecting the most effective DMT, e.g., family planning, conception and pregnancy, or the need for vaccination.

An Immunomodulatory Peptide Dendrimer Inspired from Glatiramer Acetate

Glatiramer acetate (GA) is a random polypeptide drug used to treat multiple sclerosis (MS), a chronic autoimmune disease. With the aim of identifying a precisely defined alternative to GA, we synthesized a library of peptide dendrimers with an amino acid composition similar to GA. We then challenged the dendrimers to trigger the release of the anti-inflammatory cytokine interleukin-1 receptor antagonist (IL-1Ra) from human monocytes, which is one of the effects of GA on immune cells. Several of the largest dendrimers tested were as active as GA. Detailed profiling of the best hit showed that this dendrimer induces the differentiation of monocytes towards an M2 (anti-inflammatory) state as GA does, however with a distinct immune marker profile. Our peptide dendrimer might serve as starting point to develop a well-defined immunomodulatory analog of GA.

Lymphomatoid papulosis in a patient treated with glatiramer acetate and the glatiramoid Glatopa for multiple sclerosis: A case report

A 48-year-old Caucasian woman with history of multiple sclerosis (MS) presented with erythematous papulonodular lesions in her extremities and trunk. She was being treated with glatiramer acetate (GA) for the past 10 years and the glatiramoid, Glatopa, for 2 years prior to this presentation. A skin biopsy showed CD30⁺ lymphoproliferative disorder consistent with lymphomatoid papulosis (LyP). Three weeks after stopping Glatopa, her skin lesions were improved. It remains unclear whether GA’s or Glatopa’s capability to alter T-cell differentiation, may have a link with LyP. This case report is a reminder to be vigilant for skin lesions in patients with MS.

Evaluating Effects of Glatiramer Acetate Treatment on Amyloid Deposition and Tau Phosphorylation in the 3xTg Mouse Model of Alzheimer's Disease

Neuroinflammation driven by the accumulation of amyloid β (Aβ) can lead to neurofibrillary tangle formation in Alzheimer's Disease (AD). To test the hypothesis that an anti-inflammatory immunomodulatory agent might have beneficial effects on amyloid and tau pathology, as well as microglial phenotype, we evaluated glatiramer acetate (GA), a multiple sclerosis drug thought to bias type 2 helper T (T_h2) cell responses and alternatively activate myeloid cells. We administered weekly subcutaneous injections of GA or PBS to 15-month-old 3xTg AD mice, which develop both amyloid and tau pathology, for a period of 8 weeks. We found that subcutaneous administration of GA improved behavioral performance in novel object recognition and decreased Aβ plaque in the 3xTg AD mice. Changes in tau phosphorylation were mixed with specific changes in phosphoepitopes seen in immunohistochemistry but not observed in western blot. In addition, we found that there was a trend toward increased microglia complexity in 3xTg mice treated with GA, suggesting a shift toward homeostasis. These findings correlated with subtle changes in the microglial transcriptome, in which the most striking difference was the upregulation of Dcstamp. Lastly, we found no evidence of changes in proportions of major helper T cell (T_h) subtypes in the periphery. Overall, our study provides further evidence for the benefits of immunomodulatory therapies that alter the adaptive immune system with the goal of modifying microglia responses for the treatment of Alzheimer's Disease.

Adipokines as Immune Cell Modulators in Multiple Sclerosis

Multiple sclerosis (MS), a chronic inflammatory and demyelinating disease of the central nervous system (CNS), is a major clinical and societal problem, which has a tremendous impact on the life of patients and their proxies. Current immunomodulatory and anti-inflammatory therapies prove to be relatively effective; however, they fail to concomitantly stop ongoing neurological deterioration and do not reverse acquired disability. The proportion to which genetic and environmental factors contribute to the etiology of MS is still incompletely understood; however, a recent association between MS etiology and obesity was shown, with obesity greatly increasing the risk of developing MS. An altered balance of adipokines, which are white adipose tissue (WAT) hormones, plays an important role in the low-grade chronic inflammation during obesity by their pervasive modification of local and systemic inflammation. Vice versa, inflammatory factors secreted by immune cells affect adipokine function. To explore the role of adipokines in MS pathology, we will here review the reciprocal effects of adipokines and immune cells and summarize alterations in adipokine levels in MS patient cohorts. Finally, we will discuss proof-of-concept studies demonstrating the therapeutic potential of adipokines to target both neuroinflammation and neurodegeneration processes in MS.

Glatiramer acetate attenuates depressive/anxiety-like behaviors and cognitive deficits induced by post-weaning social isolation in male mice

RATIONALE

Major depressive disorder (MDD) is a debilitating disorder with adverse effects on mood, memory, and quality of life.

OBJECTIVES

In this study, the antidepressant potential of glatiramer acetate (GA), a drug used in the management of multiple sclerosis, was investigated in acute and chronic models of depression in male mice. The acute antidepressant screening was performed with the forced swim (FST) and tail suspension (TST) tests. In the chronic phase, post-weaning social isolation (SI) was used to induce depressive-/anxiety-like behaviors.

METHODS

Mice were reared in two different groups of social (SG) and isolated (IG) for 4 weeks. IG mice were treated with 0.5, 1.0, and 2.0 mg/kg of GA for the last 2 weeks of the SI period. Animals were assessed by the behavioral tests of depression, anxiety, learning, and memory, and hippocampal brain-derived neurotrophic factor (BDNF) level was measured.

RESULTS

The acute tests confirmed the antidepressant potential of GA. In the chronic phase, GA could reduce immobility time in FST (P < 0.05), increase exploration activity in open field test (P < 0.05), increase open arms duration (P < 0.05) and entries in elevated plus maze (P<0.001), and improve memory and learning in passive avoidance test (P < 0.05). The BDNF level was increased in IG mice and decreased in IG mice treated with GA.

CONCLUSIONS

Our results showed that GA improved depressive-/anxiety-like behaviors and cognitive dysfunction of SI reared mice without increasing the BDNF level which may be associated with other mechanisms of actions of GA.

Effect of switching glatiramer acetate formulation from 20 mg daily to 40 mg three times weekly on immune function in multiple sclerosis

Background

Many RRMS patients who had been treated for over 20 years with GA 20 mg/ml daily (GA20) switched to 40 mg/ml three times-a-week (GA40) to reduce injection-related adverse events. Although GA40 is as effective as GA20 in reducing annualized relapse rate and MRI activity, it remains unknown how switching to GA40 from GA20 affects the development of pathogenic and regulatory immune cells.

Objective

To investigate the difference in immunological parameters in response to GA20 and GA40 treatments.

Methods

We analyzed five pro-inflammatory cytokines (IL-1β, IL-23, IL-12, IL-18, TNF-α), and three anti-inflammatory/regulatory cytokines (IL-10, IL-13, and IL-27) in serum. In addition, we analyzed six cytokines (IFN-γ, IL-17A, GM-CSF, IL-10, IL-6, and IL-27) in cultured PBMC supernatants. The development of Th1, Th17, Foxp3 Tregs, M1-like, and M2-like macrophages were examined by flow cytometry. Samples were analyzed before and 12 months post switching to GA40 or GA20.

Results

Pro- and anti-inflammatory cytokines were comparable between the GA40 and GA20 groups. Development of Th1, Th17, M1-like macrophages, M2-like macrophages, and Foxp3 Tregs was also comparable between the two groups.

Conclusions

The immunological parameters measured in RRMS patients treated with GA40 three times weekly are largely comparable to those given daily GA20 treatment.

Vaccine Considerations for Multiple Sclerosis in the COVID-19 Era

People with multiple sclerosis (MS) are at risk for infections that can result in amplification of baseline symptoms and possibly trigger clinical relapses. Vaccination can prevent infection through the activation of humoral and cellular immune responses. This is particularly pertinent in the era of emerging novel vaccines against severe acute respiratory syndrome coronavirus 2, the virus that causes coronavirus disease 2019 (COVID-19). MS disease-modifying therapies (DMTs), which affect the immune system, may impact immune responses to COVID-19 vaccines in people with MS. The objective of this article is to provide information on immune system responses to vaccinations and review previous studies of vaccine responses in people with MS to support the safety and importance of receiving currently available and emerging COVID-19 vaccines. Immunological studies have shown that coordinated interactions between T and B lymphocytes of the adaptive immune system are key to successful generation of immunological memory and production of neutralizing antibodies following recognition of vaccine antigens by innate immune cells. CD4+ T cells are essential to facilitate CD8+ T cell and B cell activation, while B cells drive and sustain T cell memory. Data suggest that some classes of DMT, including type 1 interferons and glatiramer acetate, may not significantly impair the response to vaccination. DMTs-such as sphingosine-1-phosphate receptor modulators, which sequester lymphocytes from circulation; alemtuzumab; and anti-CD20 therapies, which rely on depleting populations of immune cells-have been shown to attenuate responses to conventional vaccines. Currently, three COVID-19 vaccines have been granted emergency use authorization in the USA on the basis of promising interim findings of ongoing trials. Because analyses of these vaccines in people with MS are not available, decisions regarding COVID-19 vaccination and DMT choice should be informed by data and expert consensus, and personalized with considerations for disease burden, risk of infection, and other factors.

COVID-19 in Patients with Multiple Sclerosis: Associations with Disease-Modifying Therapies

BACKGROUND

Disease-modifying therapies (DMTs) for multiple sclerosis (MS) target immunity and have the potential to increase the risk of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection and alter its clinical course. We assessed these risks in patients with MS (PwMS).

OBJECTIVE

The objective of this study was to describe the overall risk of coronavirus disease 2019 (COVID-19) infection, severe disease course, and potential population-level predictors of COVID-19 infection in PwMS, and to provide a context using a cohort of patients with systemic lupus erythematosus (SLE). In addition, the association of different MS DMTs with the incidence and clinical course of COVID-19 was evaluated. Safety data from the Biogen Global Safety Database are also presented on reported cases of COVID-19 in patients treated with Biogen MS therapies.

METHODS

The IBM® Explorys electronic health record database of > 72,000,000 patients from US healthcare networks identified patients with MS or SLE, with and without polymerase chain reaction-confirmed COVID-19. COVID-19 cumulative incidence, hospitalization, and deaths among DMT classes were compared using logistic regression (adjusted for age, sex, body mass index, comorbidities, and race/ethnicity). As a secondary data source to assess safety data, COVID-19 reports for Biogen MS therapies were extracted and described from Biogen's Global Safety Database.

RESULTS

30,478 PwMS with an open DMT prescription were identified within Explorys; 344 were COVID-19 positive. The most significant risk factors for acquiring COVID-19 were comorbidity score ≥ 1, body mass index ≥ 30, and Black/African ancestry. Similar risk factors were also identified for patients with SLE. Patients with MS were less likely to develop COVID-19 when treated with interferons (0.61%) and glatiramer acetate (0.51%), vs all other MS DMTs (both p < 0.001); anti-CD20 therapy was associated with the highest risk (3.45%; p < 0.0001). In the Biogen Global Safety Database, we identified 1217 patients who were COVID-19 positive treated with intramuscular interferon beta-1a, peginterferon beta-1a, natalizumab, dimethyl fumarate, diroximel fumarate, or fampridine.

CONCLUSIONS

Comorbidities, obesity, and Black/African ancestry, but not age, were associated with a higher risk of SARS-CoV-2 infection in PwMS. Interferons and glatiramer acetate were associated with a reduced COVID-19 risk, whereas anti-CD20 therapies were associated with an increased risk, within the treated MS cohort. COVID-19 safety reports for patients receiving Biogen MS therapies were consistent with the Explorys database and MS literature, illustrating the replicability and power of this approach.

Parkinson's Disease: Can Targeting Inflammation Be an Effective Neuroprotective Strategy?

The reason why dopamine neurons die in Parkinson’s disease remains largely unknown. Emerging evidence points to a role for brain inflammation in neurodegeneration. Essential questions are whether brain inflammation happens sufficiently early so that interfering with this process can be expected to slow down neuronal death and whether the contribution from inflammation is large enough so that anti-inflammatory agents can be expected to work. Here I discuss data from human PD studies indicating that brain inflammation is an early event in PD. I also discuss the role of T-lymphocytes and peripheral inflammation for neurodegeneration. I critically discuss the failure of clinical trials targeting inflammation in PD.

PEGylation enables subcutaneously administered nanoparticles to induce antigen-specific immune tolerance

The development of nanomaterials to induce antigen-specific immune tolerance has shown promise for treating autoimmune diseases. While PEGylation has been widely used to reduce host immune responses to nanomaterials, its tolerogenic potential has not been reported. Here, we report for the first time that a subcutaneous injection of PEGylated poly(lactide-co-glycolide) (PLGA) nanoparticles containing auto-antigen peptide MOG_35-55 without any tolerogenic drugs is sufficient to dramatically ameliorate symptoms after disease onset in an antigen-specific manner in a mouse model of multiple sclerosis. Neither free MOG_35-55 nor particles without PEG exhibit this efficacy. Interestingly, mechanistic studies indicate that PEGylation of nanoparticles does not reduce dendritic cell activation through direct nanoparticle-cell interactions. Instead, PEGylated nanoparticles induce lower complement activation, neutrophil recruitment, and co-stimulatory molecule expression on dendritic cells around the injection sitecompared to non-PEGylated PLGA nanoparticles, creating a more tolerogenic microenvironment in vivo. We further demonstrate that the locally recruited dendritic cells traffic to lymphoid organs to induce T cell tolerance. These results highlight the critical role of surface properties of nanomaterials in inducing immune tolerance via subcutaneous administration.

The influence of glatiramer acetate on Th17-immune response in multiple sclerosis

Glatiramer acetate (GA) is approved for the treatment of multiple sclerosis (MS). However, the mechanism of action of GA in MS is still unclear. In particular, it is not known whether GA can modulate the pro-inflammatory Th17-type immune response in MS. We investigated the effects of original GA (Copaxone^®, Teva, Israel) and generic GA (Timexone^®, Biocad, Russia) on Th17- and Th1-type cytokine production in vitro in 25 patients with relapsing-remitting MS and 25 healthy subjects. Both original and generic GA at concentrations 50–200 μg/ml dose-dependently inhibited interleukin-17 and interferon-γ production by anti-CD3/anti-CD28-activated peripheral blood mononuclear cells from MS patients and healthy subjects. This effect of GA was reproduced using purified CD4⁺ T cells, suggesting that GA can directly modulate the functions of Th17 and Th1 cells. At high concentrations (100–200 μg/ml), GA also suppressed the production of Th17-differentiation cytokines (interleukin-1β and interleukin-6) by lipopolysaccharide (LPS)-activated dendritic cells (DCs). These GA/LPS-treated DCs induced lower interleukin-17 and interferon-γ production by autologous CD4⁺ T cells compared to LPS-treated DCs. These data suggest that GA can inhibit Th17-immune response and that this inhibitory effect is preferentially exercised by direct influence of GA on T cells. We also demonstrate a comparable ability of original and generic GA to modulate pro-inflammatory cytokine production.

Long-term drug treatment in multiple sclerosis: safety success and concerns

INTRODUCTION

The portfolio of multiple sclerosis (MS) disease modifying treatments (DMTs) has significantly expanded over the past two decades. Given the lifelong use of MS pharmacotherapy, understanding their long-term safety profiles is essential in determining suitable and personalized treatment.

AREAS COVERED

In this narrative review, we summarize the short-, mid-, and long-term safety profile of currently available MS DMTs categories. In addition to the initial trial findings, safety outcomes derived from long-term extension studies (≥5-20 years) and safety-based prescription programs have been reviewed. In order to better understand the risk-benefit ratio for each particular DMT group, a short description of the DMT-based efficacy outcomes has been included.

EXPERT OPINION

Long-term extension trials, large observational studies and real-world databases allow detection of rare and potentially serious adverse events. Two-year-long trials are unable to fully capture the positive and negative effects of immune system modulation and reconstitution. DMT-based monitoring programs can provide greater insights regarding safe use of MS medications in different patient populations and clinical settings. During the process of shared DMT decision, both MS care providers and their patients should be aware of an ever-expanding number of drug-based adverse events and their influence on the risk-benefit analysis.

Repopulation of T, B, and NK cells following alemtuzumab treatment in relapsing-remitting multiple sclerosis

OBJECTIVE

To characterize long-term repopulation of peripheral immune cells following alemtuzumab-induced lymphopenia in relapsing-remitting MS (RRMS), with a focus on regulatory cell types, and to explore associations with clinical outcome measures.

METHODS

The project was designed as a multicenter add-on longitudinal mechanistic study for RRMS patients enrolled in CARE-MS II, CARE-MS II extension at the University of Southern California and Stanford University, and an investigator-initiated study conducted at the Universities of British Columbia and Chicago. Methods involved collection of blood at baseline, prior to alemtuzumab administration, and at months 5, 11, 17, 23, 36, and 48 post-treatment. T cell, B cell, and natural killer (NK) cell subsets, chemokine receptor expression in T cells, in vitro cytokine secretion patterns, and regulatory T cell (Treg) function were assessed. Clinical outcomes, including expanded disability status score (EDSS), relapses, conventional magnetic resonance imaging (MRI) measures, and incidents of secondary autoimmunity were tracked.

RESULTS

Variable shifts in lymphocyte populations occurred over time in favor of CD4+ T cells, B cells, and NK cells with surface phenotypes characteristic of regulatory subsets, accompanied by reduced ratios of effector to regulatory cell types. Evidence of increased Treg competence was observed after each treatment course. CD4+ and CD8+ T cells that express CXCR3 and CCR5 and CD8+ T cells that express CDR3 and CCR4 were also enriched after treatment, indicating heightened trafficking potential in activated T cells. Patterns of repopulation were not associated with measures of clinical efficacy or secondary autoimmunity, but exploratory analyses using a random generalized estimating equation (GEE) Poisson model provide preliminary evidence of associations between pro-inflammatory cell types and increased risk for gadolinium (Gd+) enhancing lesions, while regulatory subsets were associated with reduced risk. In addition, the risk for T2 lesions correlated with increases in CD3+CD8+CXCR3+ cells.

CONCLUSIONS

Lymphocyte repopulation after alemtuzumab treatment favors regulatory subsets in the T cell, B cell, and NK cell compartments. Clinical efficacy may reflect the sum of interactions among them, leading to control of potentially pathogenic effector cell types. Several immune measures were identified as possible biomarkers of lesion activity. Future studies are necessary to more precisely define regulatory and effector subsets and their contributions to clinical efficacy and risk for secondary autoimmunity in alemtuzumab-treated patients, and to reveal new insights into mechanisms of immunopathogenesis in MS.

TRIAL REGISTRATION

Parent trials for this study are registered with ClinicalTrials.gov: CARE-MS II: NCT00548405, CARE-MS II extension: NCT00930553 and ISS: NCT01307332.

Inflammation and Oxidative Stress in Multiple Sclerosis: Consequences for Therapy Development

CNS inflammation is a major driver of MS pathology. Differential immune responses, including the adaptive and the innate immune system, are observed at various stages of MS and drive disease development and progression. Next to these immune-mediated mechanisms, other mediators contribute to MS pathology. These include immune-independent cell death of oligodendrocytes and neurons as well as oxidative stress-induced tissue damage. In particular, the complex influence of oxidative stress on inflammation and vice versa makes therapeutic interference complex. All approved MS therapeutics work by modulating the autoimmune response. However, despite substantial developments in the treatment of the relapsing-remitting form of MS, approved therapies for the progressive forms of MS as well as for MS-associated concomitants are limited and much needed. Here, we summarize the contribution of inflammation and oxidative stress to MS pathology and discuss consequences for MS therapy development.

Multiple Sclerosis and Cancer: The Ying-Yang Effect of Disease Modifying Therapies

Over the past two decades, the field of multiple sclerosis (MS) has been transformed by the rapidly expanding arsenal of new disease modifying therapies (DMTs). Current DMTs for MS aim to modulate innate and adaptive immune responses toward a less inflammatory phenotype. Since the immune system is also critical for identifying and eliminating malignant cells, immunosuppression from DMTs may predictably increase the risk of cancer development in MS patients. Compared with healthy controls, patients with autoimmune conditions, such as MS, may already have a higher risk of developing certain malignancies and this risk may further be magnified by DMT treatments. For those patients who develop both MS and cancer, these comorbid presentations create a challenge for clinicians on how to therapeutically address management of cancer in the context of MS autoimmunity. As there are currently no accepted guidelines for managing MS patients with prior history of or newly developed malignancy, we undertook this review to evaluate the molecular mechanisms of current DMTs and their potential for instigating and treating cancer in patients living with MS.

Inhaled nebulized glatiramer acetate against Gram-negative bacteria is not associated with adverse pulmonary reactions in healthy, young adult female pigs

The developmental speed of new antimicrobials does not meet the emergence of multidrug-resistant bacteria sufficiently. A potential shortcut is assessing the antimicrobial activity of already approved drugs. Intrudingly, the antibacterial action of glatiramer acetate (GA) has recently been discovered. GA is a well-known and safe immunomodulatory drug particular effective against Gram-negative bacteria, which disrupts biological membranes by resembling the activity of antimicrobial peptides. Thus, GA can potentially be included in treatment strategies used to combat infections caused by multidrug-resistant Gram-negatives. One potential application is chronic respiratory infections caused by Pseudomonas aeruginosa, however the safety of GA inhalation has never been assessed. Here, the safety of inhaling nebulized GA is evaluated in a preclinical pig model. The potential side effects, i.e., bronchoconstriction, respiratory tract symptoms and systemic- and local inflammation were assessed by ventilator monitoring, clinical observation, biochemistry, flowcytometry, and histopathology. No signs of bronchoconstriction assessed by increased airway peak pressure, Ppeak, or decreased oxygen pressure were observed. Also, there were no signs of local inflammation in the final histopathology examination of the pulmonary tissue. As we did not observe any potential pulmonary side effects of inhaled GA, our preliminary results suggest that GA inhalation is safe and potentially can be a part of the treatment strategy targeting chronic lung infections caused by multidrug-resistant Gram-negative bacteria.

Understanding regulatory B cells in autoimmune diseases: the case of multiple sclerosis

The suppressive function of B cells is mediated mostly through their provision of cytokines with anti-inflammatory properties, in particular interleukin-10. This B cell activity has been convincingly described in mice with autoimmune, infectious, as well as malignant diseases, and evidence is accumulating of its relevance in human. This review provides a personal view of this B cell function using multiple sclerosis and its animal model experimental autoimmune encephalomyelitis as representative examples, in an attempt to bridge observations obtained in mice and human, with the goal of providing a coherent transversal framework to further explore this field, and eventually manipulate this B cell function therapeutically.

Prevotella histicola, A Human Gut Commensal, Is as Potent as COPAXONE® in an Animal Model of Multiple Sclerosis

Multiple sclerosis (MS) is a demyelinating disease of the central nervous system. We and others have shown that there is enrichment or depletion of some gut bacteria in MS patients compared to healthy controls (HC), suggesting an important role of the gut bacteria in disease pathogenesis. Thus, specific gut bacteria that are lower in abundance in MS patients could be used as a potential treatment option for this disease. In particular, we and others have shown that MS patients have a lower abundance of Prevotella compared to HC, whereas the abundance of Prevotella is increased in patients that receive disease-modifying therapies such as Copaxone® (Glatiramer acetate-GA). This inverse correlation between the severity of MS disease and the abundance of Prevotella suggests its potential for use as a therapeutic option to treat MS. Notably we have previously identified a specific strain, Prevotella histicola (P. histicola), that suppresses disease in the animal model of MS, experimental autoimmune encephalomyelitis (EAE) compared with sham treatment. In the present study we analyzed whether the disease suppressing effects of P. histicola synergize with those of the disease-modifying drug Copaxone® to more effectively suppress disease compared to either treatment alone. Treatment with P. histicola was as effective in suppressing disease as treatment with Copaxone®, whereas the combination of P. histicola plus Copaxone® was not more effective than either individual treatment. P. histicola-treated mice had an increased frequency and number of CD4⁺FoxP3⁺ regulatory T cells in periphery as well as gut and a decreased frequency of pro-inflammatory IFN-γ and IL17-producing CD4 T cells in the CNS, suggesting P. histicola suppresses disease by boosting anti-inflammatory immune responses and inhibiting pro-inflammatory immune responses. In conclusion, our study indicates that the human gut commensal P. histicola can suppress disease as efficiently as Copaxone® and may provide an alternative treatment option for MS patients.

Impact of Glatiramer Acetate on B Cell-Mediated Pathogenesis of Multiple Sclerosis

Growing evidence indicates that B cells play a key role in the pathogenesis of multiple sclerosis (MS). B cells occupy distinct central nervous system (CNS) compartments in MS, including the cerebrospinal fluid and white matter lesions. Also, it is now known that, in addition to entering the CNS, B cells can circulate into the periphery via a functional lymphatic system. Data suggest that the role of B cells in MS mainly involves their in situ activation in demyelinating lesions, leading to altered pro- and anti-inflammatory cytokine secretion, and a highly effective antigen-presenting cell function, resulting in activation of memory or naïve T cells. Clinically, B cell-depleting agents show significant efficacy in MS. In addition, many disease-modifying therapies (DMTs) traditionally understood to target T cells are now known to influence B cell number and function. One of the earliest DMTs to be developed, glatiramer acetate (GA), has been shown to reduce the total frequency of B cells, plasmablasts, and memory B cells. It also appears to promote a shift toward reduced inflammation by increasing anti-inflammatory cytokine release and/or reducing pro-inflammatory cytokine release by B cells. In the authors' opinion, this may be mediated by cross-reactivity of B cell receptors for GA with antigen (possibly myelin basic protein) expressed in the MS lesion. More research is required to further characterize the role of B cells and their bidirectional trafficking in the pathogenesis of MS. This may uncover novel targets for MS treatments and facilitate the development of B cell biomarkers of drug response.