Successful therapy with rituximab in three patients with probable neurosarcoidosis.

BACKGROUND: Neurosarcoidosis occurs in about 5-15% of patients with sarcoidosis. Therapy with corticosteroids is generally accepted as the first-line medication, followed by various immunomodulating and cytotoxic agents or combined therapy. However, some patients show an unsatisfactory outcome or have adverse events and require novel treatment strategies. METHODS: We describe three patients with systemic sarcoidosis and central nervous system involvement who received CD20-targeted B-cell depletion with rituximab. RESULTS: Treatment with rituximab was well tolerated and followed by marked remission in patients nonresponsive to other immunosuppressive agents. CONCLUSION: Rituximab may be used for patients with neurosarcoidosis who are nonresponsive to established treatment regimes.

Ovarian Reserve in Women With Neuromyelitis Optica Spectrum Disorder.

Neuromyelitis optica spectrum disorder (NMOSD) is a neuroinflammatory disease. The majority of NMOSD patients is seropositive for aquaporin-4 (AQP4) antibodies. AQP4 is the main water channel protein in the central nervous system, but has also been identified in the female reproductive system. Fertility issues and ovarian reserve has not yet been studied in females with NMOSD. The purpose of this study was to measure serum Anti-Müllerian hormone (AMH) in females with NMOSD compared to healthy controls (HC), in combination with other lifestyle and reproduction parameters. AMH is independent from the menstrual cycle and a reliable indicator of both ovarian reserve and ovarian function. We included a total of 32 reproductive-age females, 18 HC and 14 with NMOSD. We used an enzymatically amplified two-site immunoassay to determine serum AMH level. In comparison to HC, mean AMH value was reduced in NMOSD. Apart from that significantly more women with NMOSD showed low AMH levels (< 0.8 ng/ml). Low AMH was associated with disease activity. In contrast, none of the immunotherapies for NMOSD, neither any reproductive life style parameter was associated with a decreased AMH. Our results contribute to understanding of hindered fertility in females with NMOSD and enables neurologists to better counsel female patients.

Treatment of multiple sclerosis during pregnancy - safety considerations.

INTRODUCTION: Women with multiple sclerosis (MS) are treated early in the disease course with disease modifying therapies (DMT). Updated information is needed on pregnancy outcomes of DMT-exposed pregnancies and the effect of the drug withdrawal on MS disease activity. Areas covered: In this review, we will cover the most important updated management strategies in planning a pregnancy when having MS. Expert opinion: MS itself does not increase the risk of adverse pregnancy outcomes and does not negatively influence the long-term course of the disease. As MS became a treatable disease, management of DMTs before, during and after pregnancy is important. This requires updated knowledge on safety of DMTs as well as data of the effect on disease activity after drug withdrawal. A special challenge is the handling of women with highly active MS, as pregnancy might not be powerful enough to suppress the risk of rebound relapses. Exclusive breastfeeding is an option for many women who want to do so, but in cases of high disease activity and those women who do not want to breastfeed, early reintroduction of MS therapies should be considered.

Listeria rhombencephalitis mimicking a demyelinating event in an immunocompetent young patient.

BACKGROUND: Listeriosis caused by listeria monocytogenes (LM) is a potentially lethal foodborne infection of the central nervous system (CNS) and the third most common cause of bacterial meningitis. Foods most commonly implicated are soft cheeses, raw or ready-to-eat meat and pre-processed foods. The incubation time is between 11 and 70 days. Rarely LM rhombencephalitis (RE) can occur, which typically has a biphasic course with non- specific prodromal symptoms like fever, malaise, fatigue, headache, nausea and vomiting followed by cranial nerve palsies, ataxia and hemi- or tetraparesis. OBJECTIVE: To report a 31-year old immunocompetent female developing a severe abscessing RE caused by LM, which was initially assessed as a relapse after a clinically isolated syndrome (CIS). METHODS: Case report. RESULTS: Patients with CIS or multiple sclerosis, who present with brainstem symptoms should be evaluated carefully. The presence of clinical and paraclinical red flags in the diagnostic evaluation of a suspected CNS white matter disease should raise the awareness of clinicians for potential differential diagnoses.

The immunomodulatory effect of laquinimod in CNS autoimmunity is mediated by the aryl hydrocarbon receptor.

Though several functional properties of laquinimod have been identified, our understanding of the underlying mechanisms is still incomplete. Since the compound elicits similar immunomodulatory effects to ligands of the aryl hydrocarbon receptor (AhR), we compared the efficacy of laquinimod in experimental autoimmune encephalomyelitis (EAE)-afflicted wild-type and AhR-deficient mice. Laquinimod failed to ameliorate clinical symptoms and leukocyte infiltration in AhR-deficient mice; however, treatment exerted neuroprotection by elevation of brain-derived neurotrophic factor (BDNF) independent of genetic profile. Thus, our data identify the AhR pathway in these mutant mice as crucial for the immunomodulatory, but not neuroprotective, efficacy of laquinimod in EAE.

Laquinimod in the treatment of multiple sclerosis: a review of the data so far.

Laquinimod (ABR-215062) is a new orally available carboxamide derivative, which is currently developed for relapsing remitting (RR) and chronic progressive (CP) forms of multiple sclerosis (MS; RRMS or CPMS) as well as neurodegenerative diseases. Its mechanism of action may comprise immunomodulatory effects on T-cells, monocytes, and dendritic cells as well as neuroprotective effects with prominent actions on astrocytes. Laquinimod was tested in Phase II and III clinical trials in RRMS at different dosages ranging from 0.1 to 0.6 mg/day. The compound was well tolerated, yet at the dosages tested only led to moderate effects on the reduction of relapse rates as primary study endpoint in Phase III trials. In contrast, significant effects on brain atrophy and disease progression were observed. While there were no significant safety signals in the clinical trials, the Committee for Medicinal Products for Human Use (CHMP) refused marketing authorization for RRMS based on the assessment of the risk-benefit ratio with regard to data from animal studies. At present, the compound is further tested in RRMS as well as CPMS and Huntington's disease at different concentrations. Results from these trials will further inform about the clinical benefit of laquinimod in patient cohorts with a persisting, but still insufficiently met need for safe and at the same time effective oral compounds with neuroprotective effects.

Relevance of endoglin, IL-1α, IL-1ß and anti-ovarian antibodies in females with multiple sclerosis.

Few studies support the concept of reduced fertility in females with multiple sclerosis (MS). Recently we reported on reduced serum levels of Anti-Müllerian Hormone (AMH) in reproductive-age females with MS, suggestive of reduced ovarian reserve. The cause for this observation is not evident and remains speculative. The aim of the study is to examine possible immunological mechanisms interfering with fertility, as well as ovarian reserve that might affect the reproductive potential in women with MS. ELISA experiments were done to detect anti-ovarian antibodies (AOA), endoglin and interleukin (IL)-1α/-1ß in sera of 85 MS females, including 15 women with known low AMH level as a marker of ovarian reserve, compared to 63 healthy controls. Groups did not differ with respect to age, smoking habits, BMI, and use of oral contraceptives. MS females showed significantly increased endoglin values compared to healthy controls. Remarkable, the highest endoglin values were found in subjects with low AMH. AOA were neither detectable in MS patients nor control subjects. IL-1α and IL-1ß levels did not differ between groups. Our data established no relevance of IL-1α/-1ß or AOA in ovarian insufficiency/dysfunction but suggests the involvement of endoglin in RRMS.

Dietary Fatty Acids Directly Impact Central Nervous System Autoimmunity via the Small Intestine.

Growing empirical evidence suggests that nutrition and bacterial metabolites might impact the systemic immune response in the context of disease and autoimmunity. We report that long-chain fatty acids (LCFAs) enhanced differentiation and proliferation of T helper 1 (Th1) and/or Th17 cells and impaired their intestinal sequestration via p38-MAPK pathway. Alternatively, dietary short-chain FAs (SCFAs) expanded gut T regulatory (Treg) cells by suppression of the JNK1 and p38 pathway. We used experimental autoimmune encephalomyelitis (EAE) as a model of T cell-mediated autoimmunity to show that LCFAs consistently decreased SCFAs in the gut and exacerbated disease by expanding pathogenic Th1 and/or Th17 cell populations in the small intestine. Treatment with SCFAs ameliorated EAE and reduced axonal damage via long-lasting imprinting on lamina-propria-derived Treg cells. These data demonstrate a direct dietary impact on intestinal-specific, and subsequently central nervous system-specific, Th cell responses in autoimmunity, and thus might have therapeutic implications for autoimmune diseases such as multiple sclerosis.

Serum anti-Müllerian hormone levels in reproductive-age women with relapsing-remitting multiple sclerosis.

BACKGROUND: Fertility might be reduced in women with multiple sclerosis (MS), although only few studies exist and the underlying reasons are not well understood. Similar to other autoimmune diseases, a decreased ovarian reserve may contribute to impaired fertility in women with MS. Anti-Müllerian hormone (AMH) is an established marker of the ovarian reserve and an objective indicator of ovarian function, which is independent of the hypothalamus-pituitary-gonadal axis function. OBJECTIVE: The purpose of this study was to determine AMH levels in females with relapsing-remitting MS (RRMS) in combination with other reproduction and lifestyle factors. METHODS: A total of 76 reproductive-age females with RRMS and 58 healthy controls were included in this case control study. An enzymatically amplified two-site immunoassay was used to measure serum AMH level. RESULTS: Mean AMH level was significantly decreased in females with RRMS (p<0.04), and a higher proportion of females with RRMS showed very low AMH values (<0.4 ng/ml) compared to healthy controls (p<0.05). The majority of these women were currently without any disease modifying treatment. CONCLUSIONS: Our data contribute to our understanding of impaired fertility in women with MS. The unexpected finding that the majority of MS subjects with very low AMH levels were currently without medication requires further evaluation.

Neuroprotective dimethyl fumarate synergizes with immunomodulatory interferon beta to provide enhanced axon protection in autoimmune neuroinflammation.

INTRODUCTION: Despite recent advances in development of treatments for multiple sclerosis, there is still an unmet need for more effective and also safe therapies. Based on the modes of action of interferon-beta (IFN-ß) and dimethyl fumarate (DMF), we hypothesized that anti-inflammatory and neuroprotective effects may synergize in experimental autoimmune encephalomyelitis (EAE). METHODS: EAE was induced in C57BL/6 mice by immunization with MOG35-55-peptide. Murine IFN-ß was injected s.c. every other day at 10.000IU, and DMF was provided at 15mg/kg by oral gavage twice daily. Control mice received PBS injections and were treated by oral gavage with the vehicle methylcellulose. Mice were scored daily by blinded observers and histological, FACS and cytokine studies were performed to further elucidate the underlying mechanism of action. RESULTS: Combination therapy significantly ameliorated EAE disease course in comparison to controls and monotherapy with IFN-ß. Histological analyses showed a significant effect on axon preservation with almost twice as much axons present in inflamed lesions as compared to control. Remarkably, the effect on axonal preservation was more pronounced under combination therapy than with both monotherapies. Neither monotherapy nor combination therapy demonstrated modulation of cytokines and frequency of antigen presenting cells. DISCUSSION: Combination of IFN-ß and DMF resulted in greater beneficial effects with improved tissue protection as compared to the respective monotherapies. Further combination studies of these safe therapies in human disease are warranted.

Review of laquinimod and its therapeutic potential in multiple sclerosis.

INTRODUCTION: Multiple sclerosis (MS) is a chronic immunological disease of the central nervous system characterized by early inflammatory demyelination and subsequent neurodegeneration. Although major progress has occurred, MS is still an incurable disease. Further, parenteral application and/or safety issues of the currently licensed drugs are associated with low patient compliance. Thus, there remains an unmet need for the development of more effective and well-tolerated oral therapies for the treatment of MS. At this point in time, different oral available substances are under investigation and hold promise in the treatment of relapsing-remitting MS (RRMS). AREAS COVERED: The physical, chemical and pharmacological properties of laquinimod , as well as its suggested mechanisms of action, clinical efficacy and side-effect profile are reviewed. EXPERT OPINION: Laquinimod is a new orally administered synthetic drug designed as an immunomodulator. Its mechanisms of action are not yet fully elucidated. Studies in mice and humans revealed different mechanisms of action, including anti-inflammatory and neuroprotective effects. So far, Phase II and Phase III clinical trials have shown its efficacy on magnetic resonance imaging based measures of disease activity, annualized relapse rate and disability progression in RRMS patients. Current data suggest a relatively modest efficacy by measures of relapse rate and there seems to be no superiority in comparison to established disease-modifying agents in relapsing-remitting MS. Further studies are necessary to evaluate both neuroprotective efficacy and optimal dosage of laquinimod in more detail.

Oral available agents in the treatment of relapsing remitting multiple sclerosis: an overview of merits and culprits.

Multiple sclerosis (MS) is a chronic immunological disease of the central nervous system characterized by early inflammatory demyelination and subsequent neurodegeneration. Major therapeutic progress has occurred during the past decade, in particular since the introduction of immunomodulatory agents, however, MS is still an incurable disease. In addition, parenteral application of the currently licensed drugs is associated with injection-related adverse events (AEs) and low patient compliance. Thus, there remains an unmet need for the development of more effective and well tolerated oral therapies for the treatment of MS. A number of new orally administered agents including fingolimod, laquinimod, teriflunomide, cladribine, and BG-12 have been licensed recently or are currently under investigation in relapsing remitting MS patients. In multi-center, randomized, placebo-controlled phase III clinical studies, all of these agents have already shown their efficacy on both clinical disease parameters and magnetic resonance imaging-based measures of disease activity in patients with relapsing remitting MS. However, there are essential differences concerning their clinical efficacy and side-effect profiles. Additionally, the mechanisms by which these substances exert clinical efficacy have not been fully elucidated. In this article, we review the pharmaceutical properties of fingolimod, laquinimod, teriflunomide, cladribine, and BG-12; and their suggested mechanisms of action, clinical efficacy, and side-effect profiles.

Natalizumab-associated reversible encephalopathy syndrome mimicking progressive multifocal leukoencephalopathy.

Progressive multifocal leukoencephalopathy is a rare but potentially lethal adverse event in natalizumab treated multiple sclerosis patients. We report on a 40-year old Caucasian man with typical relapsing progressive multiple sclerosis, who developed a reversible leukoencephalopathy syndrome after 43 natalizumab infusions mimicking progressive multifocal leukoencephalopathy. To our knowledge, this is the first case of its kind. Our case suggests that awareness ought to be sharpened for reversible leukoencephalopathy syndrome in the follow-up of natalizumab treated multiple sclerosis patients.

Anti-inflammatory effects of levetiracetam in experimental autoimmune encephalomyelitis.

Levetiracetam (LEV) is an established anticonvulsant with numerous mechanisms of action. Apart from its anti-epileptic effects, recent experimental studies suggest anti-inflammatory properties via modulation of interleukin (IL)-1ß and transforming-growth-factor (TGF)-ß1. However, its anti-inflammatory properties have not yet been examined in an autoimmune inflammatory disease of the central nervous system (CNS). We investigated LEV anti-inflammatory properties in experimental autoimmune encephalomyelitis, an established mouse model of multiple sclerosis. FACS analyses, ELISA, histology and rt-PCR experiments were done to explore potential anti-inflammatory effects. In line with prior studies, we demonstrate that LEV modulates both the relative gene expression and secretion of IL-1ß and TGF-1ß. However, these changes were not sufficient to alter the disease course or histological parameters. Additionally, LEV showed no effects on the absolute number of different immune cell subsets. In summary, LEV showed only minor anti-inflammatory effects not sufficient to ameliorate disease course in an autoimmune inflammatory disease of CNS.

Endogenous ciliary neurotrophic factor modulates anxiety and depressive-like behavior.

On a molecular level, depression is characterized by an altered monoaminergic neurotransmission as well as a modulation of cytokines and other mediators in the central nervous system. In particular, neurotrophic factors may influence affective behavior including depression and anxiety. Ciliary neurotrophic factor (CNTF) plays an important role in the regulation of neuronal development, neuroprotection and may also influence cognitive processes. Here we investigate the affective behavior in mice deficient for CNTF (CNTF -/- mice) at young age of 10-20 weeks. CNTF -/- mice displayed an increased anxiety-like behavior with a 30% reduction of the time spent in the bright compartment of the light/dark box as well as a significantly increased startle response. In the learned helplessness paradigm, CNTF -/- mice are more prone to depressive-like behavior. In the hippocampus of 20 weeks old, but not 10 weeks old, CNTF -/- mice, these changes correlated with a loss of parvalbumin immunoreactive GABAergic interneurons and a reduction of serotonin levels as well as 5-HT receptor 1A expression. Modulation of monoaminergic neurotransmitter levels via chronic application of the antidepressants amitriptyline and citalopram did not exert beneficial effects. These data imply that endogenous CNTF plays a pivotal role for the structural maintenance of hippocampal functions and thus has an important impact on the modulation of affective behavior in rodent models of anxiety and depression.

Constitutive activity of NF-kappa B in myeloid cells drives pathogenicity of monocytes and macrophages during autoimmune neuroinflammation.

The NF-κB/REL-family of transcription factors plays a central role in coordinating the expression of a wide variety of genes controlling immune responses including autoimmunity of the central nervous system (CNS). The inactive form of NF-κB consists of a heterodimer which is complexed with its inhibitor, IκB. Conditional knockout-mice for IκBα in myeloid cells (lysMCreIκBα(fl/fl)) have been generated and are characterized by a constitutive activation of NF-κB proteins allowing the study of this transcription factor in myelin-oligodendrocyte-glycoprotein induced experimental autoimmune encephalomyelitis (MOG-EAE), a well established experimental model for autoimmune demyelination of the CNS.In comparison to controls, lysMCreIκBα(fl/fl) mice developed a more severe clinical course of EAE. Upon histological analysis on day 15 p.i., there was an over two fold increased infiltration of T-cells and macrophages/microglia. In addition, lysMCreIκBα(fl/fl) mice displayed an increased expression of the NF-κB dependent factor inducible nitric oxide synthase in inflamed lesions. These changes in the CNS are associated with increased numbers of CD11b positive splenocytes and a higher expression of Ly6c on monocytes in the periphery. Well in accordance with these changes in the myeloid cell compartment, there was an increased production of the monocyte cytokines interleukin(IL)-12 p70, IL-6 and IL-1beta in splenocytes. In contrast, production of the T-cell associated cytokines interferon gamma (IFN-gamma) and IL-17 was not influenced.In summary, myeloid cell derived NF-κB plays a crucial role in autoimmune inflammation of the CNS and drives a pathogenic role of monocytes and macrophages independently from T-cells.

Modulation of autoimmune demyelination by laquinimod via induction of brain-derived neurotrophic factor.

Laquinimod is a promising, orally available compound that has been successfully evaluated in placebo-controlled phase II/III studies of relapsing-remitting multiple sclerosis (MS). Studies are ongoing to further define laquinimod's modulatory mechanisms. Analyses in the animal model of experimental autoimmune encephalomyelitis (EAE) demonstrate that laquinimod reduces infiltration of leukocytes into the central nervous system, induces a Th1 to Th2/3 shift, and suppresses Th17 responses. To evaluate the potential neuroprotective capacity of laquinimod via modulation of brain-derived neurotrophic factor (BDNF), we analyzed the expression of BDNF in blood samples from 203 MS patients treated with laquinimod. Furthermore, we investigated the effect of laquinimod in EAE using a conditional BDNF knockout strain lacking BDNF expression in myeloid cells and T cells (LLF mice). Treatment with laquinimod resulted in a significant and persistent increase in BDNF serum levels of MS patients when compared to baseline and placebo-treated patients. LLF mice treated with laquinimod display a more severe EAE disease course in comparison to wild-type mice. Furthermore, laquinimod-treated wild-type monocytes secreted an anti-inflammatory cytokine pattern in comparison to untreated wild-type monocytes and treated LLF monocytes. Adoptive transfer of laquinimod stimulated monocytes into mice with EAE ameliorated the disease course. Consistent with immunomodulatory properties, laquinimod skewed monocytes toward a regulatory phenotype and also acted via modulation of BDNF, which may contribute to neuroprotection in MS patients.

Laquinimod: a promising oral medication for the treatment of relapsing-remitting multiple sclerosis.

INTRODUCTION: MS is a chronic immunological disease of the CNS. Due to a lack of curative treatment approaches, current principles aim at the reduction of inflammatory disease activity. Today, many different substances are under investigation in Phase III clinical trials and hold promise in the treatment of relapsing-remitting MS (RRMS). Laquinimod is a promising new orally administered substance which has demonstrated beneficial effects in placebo-controlled trials in patients with RRMS and is currently under investigation in two global Phase III trials. AREAS COVERED: The authors review the pharmaceutical properties of laquinimod, its suggested mechanisms of action, clinical efficacy and adverse profile. This review contains data that have been presented by experts in the field at international meetings and congresses and that have been published in peer-reviewed journals. EXPERT OPINION: While laquinimod has been shown to have a promising safety profile, its mechanisms of action are not completely understood and further research is necessary to clarify this. Studies conducted in EAE, the mouse model of MS, have demonstrated immunomodulatory and neuroprotective mechanisms of action. Hopefully, the two current pivotal Phase III trials currently underway will shed some light on laquinimod confirming its clinical potential and add to the current armamentarium for the treatment of RRMS.

Inflammation modulates anxiety in an animal model of multiple sclerosis.

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) characterized by inflammation, but also degenerative changes. Besides neurological deficits, the rate of affective disorders such as depression and anxiety is at least six fold increased. Many aspects of MS can be mimicked in the animal model of myelin oligodendrocyte glycoprotein experimental autoimmune encephalomyelitis (MOG-EAE). Here we investigate behavioral changes in C57BL/6 mice suffering from mild MOG-EAE. In the later phase of the disease, mice were subjected to behavioral tests including the light-dark-box (LD Box), the acoustic startle response (SR) with a pre-pulse inhibition protocol as well as the learned helplessness (LH) paradigm. Behavioral data were correlated with the motor performance in an open field and rotarod test (RR). In the RR and open field, there was no significant difference in the motor performance between controls and mice suffering from mild MOG-EAE. Yet EAE mice displayed an increased anxiety-like behavior with a 23% reduction of the time spent in the bright compartment of the LD Box as well as an increased SR. In the LH paradigm, mice suffering from MOG-EAE were twice as much prone to depressive-like behavior. These changes correlate with an increase of hippocampal tissue tumor necrosis factor alpha levels and neuronal loss in the hippocampus. Modulation of monoaminergic transmission by chronic application of the antidepressant amitriptyline resulted in a decreased startle reaction and increased hippocampal norepinephrine levels. These data imply that chronic inflammation in the CNS may impact on emotional responses in rodent models of anxiety.