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

Glatiramer acetate in situ forming gel, a new approach for multiple sclerosis treatment

BACKGROUND

Glatiramer acetate (GA), a commonly used treatment for multiple sclerosis (MS), requires long-term frequent injections to ensure its effectiveness. This often leads to adverse effects, patient noncompliance, and economic inefficiency.

OBJECTIVES

In this study, poloxamer, as a thermosensitive polymer modified by chitosan (CS) and hyaluronic acid (HA), was employed to prepare an in situ forming prolonged release formulation of GA to overcome the problems derived from frequent repeated injections and to enhance the patient compliance.

METHODS

The sol-gel formulation was produced through a cold method and optimized using design of experiments. The final product was characterized in terms of gelation time (GT), rheological behaviors, morphological properties, assay, and drug release kinetics.

RESULTS

The in vitro release rate of GA during the first 24 h was quite rapid, but then it continued at a slower rate of 0.05 mg ml-1h-1. The in vivo analysis after the subcutaneous injections showed lower levels of IL-5, IL-13, and uric acid (UA) in mice treated with the gel formulation compared with those receiving free GA in the first few days. However, after 10 days, significantly higher concentrations were detected, which continued to increase slowly.

CONCLUSION

It can be concluded that the designed thermosensitive sol-gel formula is capable of extending the effectiveness of GA and can be considered as a promising sustained release formulation for the treatment of MS.

Disease Modifying Strategies in Multiple Sclerosis: New Rays of Hope to Combat Disability?

Multiple sclerosis (MS) is the most prevalent chronic autoimmune inflammatory- demyelinating disorder of the central nervous system (CNS). It usually begins in young adulthood, mainly between the second and fourth decades of life. Usually, the clinical course is characterized by the involvement of multiple CNS functional systems and by different, often overlapping phenotypes. In the last decades, remarkable results have been achieved in the treatment of MS, particularly in the relapsing- remitting (RRMS) form, thus improving the long-term outcome for many patients. As deeper knowledge of MS pathogenesis and respective molecular targets keeps growing, nowadays, several lines of disease-modifying treatments (DMT) are available, an impressive change compared to the relative poverty of options available in the past. Current MS management by DMTs is aimed at reducing relapse frequency, ameliorating symptoms, and preventing clinical disability and progression. Notwithstanding the relevant increase in pharmacological options for the management of RRMS, research is now increasingly pointing to identify new molecules with high efficacy, particularly in progressive forms. Hence, future efforts should be concentrated on achieving a more extensive, if not exhaustive, understanding of the pathogenetic mechanisms underlying this phase of the disease in order to characterize novel molecules for therapeutic intervention. The purpose of this review is to provide a compact overview of the numerous currently approved treatments and future innovative approaches, including neuroprotective treatments as anti-LINGO-1 monoclonal antibody and cell therapies, for effective and safe management of MS, potentially leading to a cure for this disease.

Novel liposomal glatiramer acetate: Preparation and immunomodulatory evaluation in murine model of multiple sclerosis

The frequent administration rate required for Glatiramer acetate (GA), a first-line therapy for Multiple sclerosis (MS), poses patient compliance issues. Only a small portion of the subcutaneously administered GA is available for phagocytosis by macrophages, as most of it is hydrolyzed at its administration site or excreted renally. To unravel these hurdles, we have prepared liposomal formulations of GA through thin film-hydration method plus extrusion. The clinical and histopathological efficacy of GA-loaded liposomes were assessed in prophylactic and therapeutic manners on murine model of MS (experimental autoimmune encephalomyelitis (EAE)). The selected GA liposomal formulation showed favorable size (275 nm on average), high loading efficiency, and high macrophage localization. Moreover, administration of GA-liposomes in mice robustly suppressed the inflammatory responses and decreased the inflammatory and demyelinated lesion regions in CNS compared to the free GA with subsequent reduction of the EAE clinical score. Our study indicated that liposomal GA could be served as a reliable nanomedicine-based platform to hopefully curb MS-related aberrant autoreactive immune responses with higher efficacy, longer duration of action, fewer administration frequencies, and higher delivery rate to macrophages. This platform has the potential to be introduced as a vaccine for MS after clinical translation and merits further investigations.

Continued dysregulation of the B cell lineage promotes multiple sclerosis activity despite disease modifying therapies

A clear understanding of the origin and role of the different subtypes of the B cell lineage involved in the activity or remission of multiple sclerosis (MS) is important for the treatment and follow-up of patients living with this disease. B cells, however, are dynamic and can play an anti-inflammatory or pro-inflammatory role, depending on their milieu. Depletion of B cells has been effective in controlling the progression of MS, but it can have adverse side effects. A better understanding of the role of the B cell subtypes, through the use of surface biomarkers of cellular activity with special attention to the function of memory and other regulatory B cells (Bregs), will be necessary in order to offer specific treatments without inducing undesirable effects.

Synapse Dysfunctions in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic neuroinflammatory disease of the central nervous system (CNS) affecting nearly three million humans worldwide. In MS, cells of an auto-reactive immune system invade the brain and cause neuroinflammation. Neuroinflammation triggers a complex, multi-faceted harmful process not only in the white matter but also in the grey matter of the brain. In the grey matter, neuroinflammation causes synapse dysfunctions. Synapse dysfunctions in MS occur early and independent from white matter demyelination and are likely correlates of cognitive and mental symptoms in MS. Disturbed synapse/glia interactions and elevated neuroinflammatory signals play a central role. Glutamatergic excitotoxic synapse damage emerges as a major mechanism. We review synapse/glia communication under normal conditions and summarize how this communication becomes malfunctional during neuroinflammation in MS. We discuss mechanisms of how disturbed glia/synapse communication can lead to synapse dysfunctions, signaling dysbalance, and neurodegeneration in MS.

Serum levels of IgM to phosphatidylcholine predict the response of multiple sclerosis patients to natalizumab or IFN-β

We developed an ELISA assay demonstrating the high prevalence of serum IgM to phosphatidylcholine (IgM-PC) in the first stages of multiple sclerosis (MS). We aimed to analyze the role of serum IgM-PC as a biomarker of response to treatment. Paired serum samples from 95 MS patients were obtained before (b.t) and after (a.t) treatment with disease modifying therapies. Patients were classified as non-responders or responders to treatment, according to classical criteria. Serum IgM-PC concentration was analyzed using our house ELISA assay. The level of serum IgM-PC b.t was higher in patients treated later with natalizumab than in those treated with Copaxone (p = 0.011) or interferon-β (p = 0.009). Responders to natalizumab showed higher concentration of serum IgM-PC b.t than those who did not respond to it (p = 0.019). The 73.3% of patients with the highest level of serum IgM-PC b.t responded to natalizumab. IgM-PC level decreased a.t in both cases, non-responders and responders to natalizumab. IgM-PC levels a.t did not decrease in non-responders to interferon-β, but in responders to it the IgM-PC level decreased (p = 0.007). Serum IgM-PC could be a biomarker of response to natalizumab or interferon-β treatment. Further studies would be necessary to validate these results.

Blood-brain barrier: emerging trends on transport models and new-age strategies for therapeutics intervention against neurological disorders

The integrity of the blood–brain barrier (BBB) is essential for normal central nervous system (CNS) functioning. Considering the significance of BBB in maintaining homeostasis and the neural environment, we aim to provide an overview of significant aspects of BBB. Worldwide, the treatment of neurological diseases caused by BBB disruption has been a major challenge. BBB also restricts entry of neuro-therapeutic drugs and hinders treatment modalities. Hence, currently nanotechnology-based approaches are being explored on large scale as alternatives to conventional methodologies. It is necessary to investigate the in-depth characteristic features of BBB to facilitate the discovery of novel drugs that can successfully cross the barrier and target the disease effectively. It is imperative to discover novel strategies to treat life-threatening CNS diseases in humans. Therefore, insights regarding building blocks of BBB, activation of immune response on breach of this barrier, and various autoimmune neurological disorders caused due to BBB dysfunction are discussed. Further, special emphasis is given on delineating BBB disruption leading to CNS disorders. Moreover, various mechanisms of transport pathways across BBB, several novel strategies, and alternative routes by which drugs can be properly delivered into CNS are also discussed.

Lymphocyte Counts and Multiple Sclerosis Therapeutics: Between Mechanisms of Action and Treatment-Limiting Side Effects

Although the detailed pathogenesis of multiple sclerosis (MS) is not completely understood, a broad range of disease-modifying therapies (DMTs) are available. A common side effect of nearly every MS therapeutic agent is lymphopenia, which can be both beneficial and, in some cases, treatment-limiting. A sound knowledge of the underlying mechanism of action of the selected agent is required in order to understand treatment-associated changes in white blood cell counts, as well as monitoring consequences. This review is a comprehensive summary of the currently available DMTs with regard to their effects on lymphocyte count. In the first part, we describe important general information about the role of lymphocytes in the course of MS and the essentials of lymphopenic states. In the second part, we introduce the different DMTs according to their underlying mechanism of action, summarizing recommendations for lymphocyte monitoring and definitions of lymphocyte thresholds for different therapeutic regimens.

Multiple sclerosis and immune system biomarkers: Novel comparison in glatiramer acetate and interferon beta-1a-treated patient groups

BACKGROUND

Multiple sclerosis (MS) is a chronic, demyelinating disease of the central nervous system (CNS). T cells and B lymphocytes are involved in the development of this disease.

METHODS

The following biomarkers were determined in peripheral blood in 28 patients treated with glatiramer acetate (GA) and 21 patients treated with interferon beta 1-a (IFN): IL-10, BAFF, Mx1, IgG, IgG1, IgG2, IgG3 and IgG4 (at baseline and after 6 months of treatment). All participants had confirmed MS diagnosis.

OBJECTIVES

The primary objective is to assess a percentual change of biomarkers after 6 months since the first-line treatment initiation with GA or IFN. The secondary objective is to explore correlations between the baseline biomarkers' values (levels).

RESULTS

A positive trend was observed in the increase in IL-10 concentration by 30.33 % (IFN) and by 15.65 % (GA). In the IFN group, we observed a statistically significant increase in the BAFF protein concentration by 29.9% (P < 0.001). We found that Mx1 protein levels did not change with the administration of GA, which can be explained by the different mechanisms of action of GA. The serum levels of IgG immunoglobulins and both IgG1 and IgG4 subclasses in both groups of patients were increased. Thus, our data were in accordance with the generally accepted assumption that both IFN and GA are capable of modulating the B cell system.

CONCLUSIONS

Our results suggest that treatment with IFN and GA has a more pronounced influence on the B cell system of MS.

The identification, development and therapeutic potential of IL-10-producing regulatory B cells in multiple sclerosis

Regulatory B cells are a rare B-cell subset widely known to exert their immunosuppressive function via the production of interleukin-10 (IL-10) and other mechanisms. B10 cells are a special subset of regulatory B cells with immunoregulatory function that is fully attributed to IL-10. Their unique roles in the animal model of multiple sclerosis (MS) have been described, as well as their relevance in MS patients. This review specifically focuses on the identification and development of B10 cells, the signals that promote IL-10 production in B cells, the roles of B10 cells in MS, and the potential and major challenges of the application of B10-based therapies for MS.

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.

EBV-specific CD8 T lymphocytes and B cells during glatiramer acetate therapy in patients with MS

Objective

Infection with Epstein-Barr virus (EBV) has been associated with clinical activity and risk of developing MS. The purpose of this study is to investigate the impact of glatiramer acetate (GA) therapy on EBV-specific immune responses and disease course.

Methods

We characterized EBV-specific CD8 T lymphocytes and B cells during disease-modifying treatments in 2 groups of patients with MS. We designed a 2-pronged approach consisting of a cross-sectional study (39 untreated patients, 38 patients who had undergone 12 months of GA treatment, and 48 healthy donors compatible for age and sex with the patients with MS) and a 12-month longitudinal study (35 patients treated with GA). CD8 EBV-specific T cells and B lymphocytes were studied using pentamers and multiparametric flow cytometry.

Results

We find that treatment with GA enhances viral recognition by inducing an increased number of circulating virus-specific CD8 T cells (p = 0.0043) and by relieving their features of exhaustion (p = 0.0053) and senescence (p < 0.0001, p = 0.0001). B cells, phenotypically and numerically tracked along the 1-year follow-up study, show a steady decrease in memory B-cell frequencies (p = 0.025), paralleled by an increase of the naive B subset.

Conclusion

GA therapy acts as a disease-modifying therapy restoring homeostasis in the immune system, including anti-EBV responses.

Differential effects of disease modifying drugs on peripheral blood B cell subsets: A cross sectional study in multiple sclerosis patients treated with interferon-β, glatiramer acetate, dimethyl fumarate, fingolimod or natalizumab

Background

Several disease modifying drugs (DMDs) have been approved for the treatment of multiple sclerosis (MS), however, little is known about their differential impact on peripheral blood (PB) B cell subsets.

Methods

We performed a cross sectional study on PB B cells in MS patients treated with interferon-β (n = 25), glatiramer acetate (n = 19), dimethyl fumarate (n = 15), fingolimod (n = 16) or natalizumab (n = 22), untreated MS patients (n = 20), and in patients with non-inflammatory neurological diseases (n = 12). Besides analyzing routine laboratory data, flow cytometry was performed to analyze naïve B cells (CD19+CD20+CD27-IgD+), non-class switched (CD19+CD20+CD27+IgD+) and class-switched memory B cells (CD19+CD20+CD27+IgD-), double negative B cells (CD19+CD20lowCD27-IgD-) and plasmablasts (CD19+CD20lowCD27+CD38++).

Results

Treatment associated changes were found for the overall B cell pool as well as for all B cell subsets. Natalizumab increased absolute numbers and percentage of all B cells mainly by expanding the memory B cell pool. Fingolimod decreased absolute numbers of all B cell subsets and the percentage of total B cells. Fingolimod, dimethyl fumarate and interferon-β treatments were associated with an increase in the fraction of naïve B cells while class switched and non-class switched memory B cells showed decreased percentages.

Conclusion

Our results highlight differential effects of DMDs on the PB B cell compartment. Across the examined treatments, a decreased percentage of memory B cells was found in dimethyl fumarate, interferon-β and fingolimod treated patients which might contribute to the drugs’ mode of action in MS. Further studies are necessary to decipher the exact role of B cell subsets during MS pathogenesis.

Differential Effects of MS Therapeutics on B Cells-Implications for Their Use and Failure in AQP4-Positive NMOSD Patients

B cells are considered major contributors to multiple sclerosis (MS) pathophysiology. While lately approved disease-modifying drugs like ocrelizumab deplete B cells directly, most MS medications were not primarily designed to target B cells. Here, we review the current understanding how approved MS medications affect peripheral B lymphocytes in humans. These highly contrasting effects are of substantial importance when considering these drugs as therapy for neuromyelitis optica spectrum disorders (NMOSD), a frequent differential diagnosis to MS, which is considered being a primarily B cell- and antibody-driven diseases. Data indicates that MS medications, which deplete B cells or induce an anti-inflammatory phenotype of the remaining ones, were effective and safe in aquaporin-4 antibody positive NMOSD. In contrast, drugs such as natalizumab and interferon-β, which lead to activation and accumulation of B cells in the peripheral blood, lack efficacy or even induce catastrophic disease activity in NMOSD. Hence, we conclude that the differential effect of MS drugs on B cells is one potential parameter determining the therapeutic efficacy or failure in antibody-dependent diseases like seropositive NMOSD.

A case of Disseminated Herpes Zoster in a patient with Multiple Sclerosis on Glatiramer acetate

We present a case of Disseminated Herpes Zoster in a 73 year old man who had been taking Glatiramer acetate for 8 years as treatment for Multiple Sclerosis. He presented to the emergency room with complaints of a painful skin lesions on his buttocks and was found to have a generalized papulo-pustular rash. He was treated with IV Acyclovir and concurrent Piperacillin-Tazobactam plus Vancomycin for disseminated herpes zoster with a necrotic bacterial superinfection on his buttocks. Multiple Sclerosis is a chronic immune mediated disease of the CNS and is treated with immunomodulators and immunosuppressive medications. With more than 2 decades of Glatiramer acetate use, it is regarded as the safest immunomodulator without any associated reported infections. This is the first case of Disseminated Herpes Zoster associated with Glatiramer.

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.

Glatiramer acetate protects against oxygen-glucose deprivation/reperfusion-induced injury by inhibiting Egr-1 in H9c2 cells

Myocardial infarction (MI) or heart attack is a deadly event with high prevalence. In the present study, we investigated the effects of the polypeptide copolymer glatiramer acetate (GA) in H9c2 rat cardiomyocytes exposed to oxygen-glucose deprivation/reperfusion injury. Immediately following MI, an acute inflammatory response is triggered that causes activation of various proinflammatory cytokines, infiltration of immune cells, and neovascularization. This response is largely mediated by some genes such as TNF-α, IL-6, ICAM-1, and VEGF. Additionally, the rapid influx of oxidants, such as reactive oxygen species (ROS), leads to a harmful state of oxidative stress. Here, we found that GA could reduce OGD/R-induced inflammation and oxidative stress by inhibiting the expression of TNF-α, IL-6, ICAM-1, and VEGF, and suppressing the production of ROS via reduced NADPH oxidase 1 (NOX1) expression. To elucidate the pathways involved in these promising results, we took a close look at the impact of the endothelial growth response-1 (Egr-1), a transcriptional factor recognized as a mediator of MI-related inflammation and cellular injury. Using siRNA for Egr-1, we found that GA could reduce the expression of ICAM-1 and VEGF by inhibiting Egr-1 expression. Together, our findings indicate a novel therapeutic potential of GA in the treatment of MI.

JNK and phosphorylated Bcl-2 predict multiple sclerosis clinical activity and glatiramer acetate therapeutic response

In this study, we investigated the role of JNK and phospho-Bcl-2 as possible biomarkers of multiple sclerosis (MS) relapse and of glatiramer acetate (GA) therapeutic response in relapsing-remitting MS patients. We enrolled a cohort of 15 GA-treated patients and measured the expression of JNK1, JNK2, phospho-JNK and phospho-Bcl-2 through Western blotting of lysates from peripheral blood mononuclear cells collected at 0, 3, 6, and 12 months after initiating GA therapy. We found significantly higher levels of JNK1 p54 and JNK2 p54 and significantly lower levels of p-Bcl-2 in relapse patients and in GA non-responders. By using receiver operating characteristic analysis, we found that the probability of accurately detecting relapse and response to GA was: 92% and 75.5%, respectively, for JNK1 p54 and 86% and 94.6%, respectively, for p-Bcl-2. Our data suggest that JNK1 and p-Bcl-2 could serve as potential biomarkers for MS relapse and the therapeutic response to GA.

Immunological Aspects of Approved MS Therapeutics

Multiple sclerosis (MS) is the most common neurological immune-mediated disease leading to disability in young adults. The outcome of the disease is unpredictable, and over time, neurological disabilities accumulate. Interferon beta-1b was the first drug to be approved in the 1990s for relapsing-remitting MS to modulate the course of the disease. Over the past two decades, the treatment landscape has changed tremendously. Currently, more than a dozen drugs representing 1 substances with different mechanisms of action have been approved (interferon beta preparations, glatiramer acetate, fingolimod, siponimod, mitoxantrone, teriflunomide, dimethyl fumarate, cladribine, alemtuzumab, ocrelizumab, and natalizumab). Ocrelizumab was the first medication to be approved for primary progressive MS. The objective of this review is to present the modes of action of these drugs and their effects on the immunopathogenesis of MS. Each agent's clinical development and potential side effects are discussed.

A differential sex-specific pattern of IgG2 and IgG4 subclasses of anti-drug antibodies (ADAs) induced by glatiramer acetate in relapsing-remitting multiple sclerosis patients

BACKGROUND

Glatiramer acetate (GA) is a drug for Multiple Sclerosis (MS) treatment. However, its administration induces anti-drug antibodies (ADA). This research evaluated the sex differences in humoral response against GA in RR-MS patients METHODS: We analyzed 69 RR-MS patients, 43 treated with GA and 26 treated with IFN-β. In all cases, the serum concentration of IgG antibodies was determined by UPLC, whereas the levels of IgG subclasses (1-4) of anti-GA antibodies and the concentration of IL-6 were detected by Multiplex and IL-10, and IFN-γ were detected by ELISA.

RESULTS

The total concentration of IgG antibodies in patients did not differ between treatments, whereas the IgG levels of ADA were higher in male and female patients treated with GA (P ≤ 0.0001). The subclasses of IgG anti-GA antibodies were as follows: IgG4>>IgG3>IgG1>IgG2. Statistical analysis showed differences in the IgG2 (P ≤ 0.01) and IgG4 (P ≤ 0.0001) subclasses by sex in RR-MS patients. Levels of IgG1 subclass in male patients correlated positively with the circulatory levels of IL-6 (r_s = 0.587, P ≤ 0.04) and IFN-γ (r_s = 0.721, P ≤ 0.001), while IgG2 subclass levels in female patients correlated with serum levels of IFN-γ (r_s = 0.628, P ≤ 0.0006). Statistical analysis did not detect correlations between the levels of IgG (1-4) subclasses of anti-GA antibodies and the evaluated clinical parameters.

CONCLUSION

This study showed differences in the levels of IgG2 and IgG4 subclasses of ADA between male and female RR-MS patients. Further studies are necessary to take advantage of the clinical potential of this finding.

B Cell-based Therapies for Multiple Sclerosis

The traditional view of multiple sclerosis (MS) as a T cell mediated autoimmune disease of the central nervous system (CNS) has evolved into a concept of an immune-mediated disease where complex bi-directional interactions between T cells, B cells and myeloid cells underlie and shape CNS-directed autoimmunity. B cells are now recognized as major contributors to the pathogenesis of MS, largely due to increased understanding of their biology and the profound anti-inflammatory effects demonstrated by B cell depletion in MS. In this chapter we discuss the fundamental roles B cells play in the pathogenesis of MS and review current and future therapeutic strategies targeting B cells in MS, including B cell depletion with various monoclonal antibodies (mAbs) against the B cell surface markers CD20 and CD19, anti-B cell cytokine therapies, blocking Bruton's tyrosine kinase (BTK) in B cells, and various immunomodulatory and immunosuppressive effects exerted on B cells by virtually all other approved therapies for MS.