Increased autophagy in peripheral nerves may protect Wistar Ottawa Karlsburg W rats against neuropathy.

OBJECTIVE: Wistar Ottawa Karlsburg W (RT1(u)) rats (WOKW) develop obesity, dyslipidemia, moderate hypertension, hyperinsulinemia and impaired glucose tolerance prone to induce peripheral neuropathy (PN). Autophagy has been shown to prevent neurodegeneration in the central and peripheral nervous system. We analyzed the potential protective role of autophagy in an established rat model in preventing PN. METHODS: We examined electrophysiology (motor-and sensory/mixed afferent conduction velocities and the minimal F-wave latency) and morphology, including ultrathin sections, myelin sheath thickness (g-ratio) and immunohistochemical markers of autophagy and inflammation in the sciatic nerve of five-month-old, male WOKW as compared to Wistar derived, congenic LEW.1W control rats, characterized by the same major histocompatibility complex as WOKW rats (RT1(u)). Moreover, the expression of axonal and synaptic proteins (NF68, GAP43, MP0), autophagy- (Atg5, Atg7, LC3), and apoptosis (cleaved caspase-3)-related markers was measured using Western blot. RESULTS: No abnormalities in nerve electrophysiology and morphology were found in WOKW compared to LEW.1W rats. However, autophagosomes were more frequently apparent in sciatic nerves of WOKW rats. In Western blot analyses no significant differences in expression of neuronal structural proteins were found, but autophagy markers were up-regulated in WOKW compared to LEW.1W sciatic nerves. Immunostaining revealed a greater infiltration of Iba1/ED-1-positive macrophages, CD-3-positive T-cells and LC3-expression in sciatic nerves of WOKW rats. CONCLUSIONS: Our results indicate that WOKW rats show an up-regulated autophagy and a mild inflammatory response but do not develop overt neuropathy. We suggest that autophagy and inflammatory cells may exert a protective role in preventing neuropathy in this rat model of the metabolic syndrome but the mechanism of action is still unclear.

Fatal PML associated with efalizumab therapy: insights into integrin αLß2 in JC virus control.

OBJECTIVES: Progressive multifocal leukoencephalopathy (PML) has become much more common with monoclonal antibody treatment for multiple sclerosis and other immune-mediated disorders. METHODS: We report 2 patients with severe psoriasis and fatal PML treated for ≥3 years with efalizumab, a neutralizing antibody to αLß2-leukointegrin (LFA-1). In one patient, we conducted serial studies of peripheral blood and CSF including analyses of leukocyte phenotypes, migration ex vivo, and CDR3 spectratypes with controls coming from HIV-infected patients with PML. Extensive pathologic and histologic analysis was done on autopsy CNS tissue of both patients. RESULTS: Both patients developed progressive cognitive and motor deficits, and JC virus was identified in CSF. Despite treatment including plasma exchange (PE) and signs of immune reconstitution, both died of PML 2 and 6 months after disease onset. Neuropathologic examination confirmed PML. Efalizumab treatment was associated with reduced transendothelial migration by peripheral T cells in vitro. As expression levels of LFA-1 on peripheral T cells gradually rose after PE, in vitro migration increased. Peripheral and CSF T-cell spectratyping showed CD8+ T-cell clonal expansion but blunted activation, which was restored after PE. CONCLUSIONS: From these data we propose that inhibition of peripheral and intrathecal T-cell activation and suppression of CNS effector-phase migration both characterize efalizumab-associated PML. LFA-1 may be a crucial factor in homeostatic JC virus control.

Serum antibodies to conformational and linear epitopes of myelin oligodendrocyte glycoprotein are not elevated in the preclinical phase of multiple sclerosis.

BACKGROUND: The proposed predictive value of serum anti-myelin antibodies for the development of multiple sclerosis after a first clinically isolated syndrome was recently challenged. OBJECTIVE: To investigate myelin autoantibodies before first disease manifestation using different detection methods. METHODS: Patients with multiple sclerosis who had donated blood at a time prior to development of clinically isolated syndrome were identified via the German National Multiple Sclerosis Society. Control sera were obtained from age- and gender-matched blood donors. IgG-/IgM-antibodies against the extracellular part of native, cell surface-expressed myelin oligodendrocyte glycoprotein were detected by flow cytometry. Antibodies against linear epitopes were identified by immunoblot using recombinant myelin oligodendrocyte glycoprotein (aa1-125) and human myelin basic protein preparations. RESULTS: Fifty eight serum samples from 25 patients covering an interval of 7.3 years-2 months prior to disease onset were available. Longitudinal investigations were performed in 19 patients (2-14 samples per patient, 7 years-2 months prior to disease onset). No significant differences in the prevalence or titres of anti-myelin antibodies were detected between sera of preclinical individuals and healthy donors by either flow cytometry or immunoblot. There was no correlation between interval before clinically isolated syndrome and autoantibody status. Occurrence of antibodies was not associated with symptomatology/severity of clinically isolated syndrome. CONCLUSION: Neither anti-myelin autoantibodies against cell surface-expressed native myelin oligodendrocyte glycoprotein nor against linear epitopes have a predictive or discriminative role during the preclinical disease phase for developing clinically isolated syndrome or multiple sclerosis later in life.

Elevated proinflammatory cytokine expression in affected skin in small fiber neuropathy.

BACKGROUND: Small fiber neuropathy (SFN) is a subtype of sensory neuropathy with acral pain and normal findings in routine nerve conduction studies. METHODS: Twenty-four patients with SFN and matched controls were prospectively studied in this case-control study. Patients were assessed clinically, with standardized pain and depression questionnaires, by neurophysiologic tests, and by quantitative sensory testing. All patients underwent skin punch biopsy in a clinically affected (distal calf) and a nonaffected area (proximal thigh). Blood samples were collected for systemic cytokine gene expression analysis. RESULTS: Patients with SFN had a 2-fold higher gene expression for interleukin (IL)-2 (p < 0.0001), IL-10 (p = 0.01), and transforming growth factor-beta1 (p = 0.001) in peripheral blood. Skin samples from affected areas showed increased IL-6 (7-fold; p = 0.001) and IL-8 (5-fold; p = 0.002) gene expression when compared to healthy controls. In 10/24 patients, SFN was termed length-dependent (LD) because of a > or =5-fold higher intraepidermal nerve fiber density in the proximal than in the distal skin. Patients with LD-SFN had higher gene expression in the affected distal skin than in nonaffected skin for tumor necrosis factor-alpha (2.6-fold; p = 0.04), IL-1beta (2-fold; p = 0.02), IL-6 (>200-fold; p = 0.01), and IL-8 (>500-fold; p = 0.046). Inflammatory cells were present in most SFN samples but their numbers were not correlated with cytokine levels. CONCLUSIONS: Elevated local proinflammatory cytokines may be involved in the pathophysiology of pain in length-dependent small fiber neuropathy. These findings suggest a potential therapeutic role of locally applied cytokine inhibitors.

[Amyotrophic lateral sclerosis: management of bulbar symptoms]. / Amyotrophe Lateralsklerose: Symptomatische Therapie bulbärer Symptome.

Symptomatic treatment of amyotrophic lateral sclerosis (ALS) is relevant in preventing complications and improving quality of life as long as curative therapies are still out of sight. About one third of ALS patients show disabling problems associated with dysarthria, dysphagia, sialorrhea, and a pseudobulbar affective disorder already in the early stages of ALS. A multidisciplinary approach is the cornerstone of symptomatic treatment of bulbar and pseudobulbar ALS features. Except for riluzole randomized controlled trials are lacking. Here, we review the current views with regard to epidemiology, pathophysiology, diagnosis, and practical aspects of treating bulbar and pseudobulbar symptoms.

Rapid-onset central motor plasticity in multiple sclerosis.

OBJECTIVE: To study rapid-onset central motor plasticity, and its relationship to motor impairment and CNS injury in patients with multiple sclerosis (MS). METHODS: In this cross-sectional observational study, motor plasticity was examined neurophysiologically and behaviorally in 22 patients with moderately severe (median Expanded Disability Status Scale score 2.5 [0-6]) stable MS and matched healthy controls. First, plasticity was assessed using paired associative stimulation (PAS), a protocol modeling long-term synaptic potentiation in human cortex. PAS combines repetitive electric nerve stimulation with transcranial magnetic stimulation (TMS) of the contralateral motor cortex. Second, motor learning was tested by a force production task. Motor impairment was assessed by functional tests. CNS injury was evaluated by obtaining normalized N-acetyl-aspartate (NAA/Cr) spectra using magnetic resonance spectroscopy and by the corticomuscular latency (CML) to the abductor pollicis brevis muscle as tested by TMS. RESULTS: Patients with MS performed worse than controls in functional motor tests, CMLs were prolonged, and NAA/Cr was decreased. PAS-induced enhancement of corticospinal excitability and training-induced increments of motor performance were comparable between patients with MS and controls. Neither PAS-induced plasticity nor motor learning performance correlated with motor impairment or measures of CNS injury. Patients with high CNS injury and good motor performance did not differ significantly from those with high CNS injury and poor motor performance with respect to PAS-induced plasticity and motor learning success. CONCLUSIONS: Despite motor impairment and CNS injury in patients with multiple sclerosis (MS), rapid-onset motor plasticity is comparable to that in healthy subjects. Compensation of MS-related CNS injury is unlikely to be constrained by insufficient rapid-onset neuroplasticity.

The PTPN22gain-of-function+1858T(+) genotypes correlate with low IL-2 expression in thymomas and predispose to myasthenia gravis.

Protein tyrosine phosphatase, non-receptor type 22 (PTPN22) inhibits T-cell activation and interleukin-2 (IL-2) production. The PTPN22(gain-of-function)+1858T(+) genotypes predispose to multiple autoimmune diseases, including early-onset (non-thymomatous) myasthenia gravis (MG). The disease association and the requirement of IL-2/IL-2 receptor signaling for intrathymic, negative T-cell selection have suggested that these genotypes may weaken T-cell receptor (TCR) signaling and impair the deletion of autoreactive T cells. Evidence for this hypothesis is missing. Thymoma-associated MG, which depends on intratumorous generation and export of mature autoreactive CD4(+) T cells, is a model of autoimmunity because of central tolerance failure. Here, we analyzed the PTPN22 +1858C/T single nucleotide polymorphism in 426 German Caucasian individuals, including 125 thymoma patients (79 with MG), and investigated intratumorous IL-2 expression levels. Unlike two previous studies on French and Swedish patients, we found strong association of PTPN22 +1858T(+) genotypes not only with early-onset MG (P=0.00034) but also with thymoma-associated MG (P=0.0028). IL-2 expression in thymomas with PTPN22 +1858T(+) genotypes (P=0.028) was lower, implying weaker TCR signaling. We conclude that the PTPN22(gain-of-function) variant biases towards MG in a subgroup of thymoma patients possibly by impeding central tolerance induction.

Altered innate immune response of plasmacytoid dendritic cells in multiple sclerosis.

Plasmacytoid dendritic cells (pDCs) are of crucial importance in immune regulation and response to microbial factors. In multiple sclerosis (MS), pDCs from peripheral blood showed an immature phenotype, but its role in susceptibility to MS is not determined. Because infectious diseases are established triggers of exacerbations in MS, in this study we have characterized the expression of Toll-like receptors (TLR) and the maturation and functional properties of peripheral blood pDCs from clinically stable, untreated MS patients in response to signals of innate immunity. After stimulation of TLR-9, interferon (IFN)-alpha production by pDCs was significantly lower in MS (n = 12) compared to healthy controls (n = 9). In an allogenic two-step co-culture assay we found an impaired effect of TLR-9 stimulation on IFN-gamma expression of autologous naive T cells in MS patients (n = 4). In peripheral blood mononuclear cells, TLR-9 stimulation with type A CpG ODN resulted in a higher expression of TLR-1, -2, -4, -5 and -8 in MS patients (n = 7) compared with healthy controls (n = 11). These findings suggest an altered innate immune response to microbial stimuli in MS patients and may help understanding of why common infectious agents trigger MS attacks.

Stiff person syndrome associated anti-amphiphysin antibodies reduce GABA associated [Ca(2+)]i rise in embryonic motoneurons.

Autoantibodies to the synaptic protein amphiphysin play a crucial pathogenic role in paraneoplastic stiff-person syndrome. Impairment of GABAergic inhibition is the presumed pathophysiological mechanism by which these autoantibodies become pathogenic. Here we used calcium imaging on rat embryonic motor neurons to investigate whether antibodies to amphiphysin directly hinder GABAergic signaling. We found that the immunoglobulin G fraction from a patient with stiff-person syndrome, containing high titer antibodies to amphiphysin and inducing stiffness in rats upon passive transfer, reduced GABA-induced calcium influx in embryonic motor neurons. Depletion of the anti-amphiphysin fraction from the patient's IgG by selective affinity chromatography abolished this effect, showing its specificity for amphiphysin. Quantification of the surface expression of the Na(+)/K(+)/2Cl(2-) cotransporter revealed a reduction after incubation with anti-amphiphysin IgG, which is concordant with a lower intracellular chloride concentration and thus impairment of GABA mediated calcium influx. Thus, anti-amphiphysin antibodies exert a direct effect on GABA signaling, which is likely to contribute to the pathogenesis of SPS.

Basic and escalating immunomodulatory treatments in multiple sclerosis: current therapeutic recommendations.

This review updates and extends earlier Consensus Reports related to current basic and escalating immunomodulatory treatments in multiple sclerosis (MS). The recent literature has been extracted for new evidence from randomized controlled trials, open treatment studies and reported expert opinion, both in original articles and reviews, and evaluates indications and safety issues based on published data. After data extraction from published full length publications and critically weighing the evidence and potential impact of the data, the review has been drafted and circulated within the National MS Societies and the European MS Platform to reach consensus within a very large group of European experts, combining evidence-based criteria and expert opinion where evidence is still incomplete. The review also outlines a few areas of controversy and delineates the need for future research.

Symptomatic treatment of multiple sclerosis. Multiple Sclerosis Therapy Consensus Group (MSTCG) of the German Multiple Sclerosis Society.

Besides immunomodulation and immunosuppression, the specific treatment of symptoms is an essential component of the overall management of multiple sclerosis (MS). Symptomatic treatment is aimed at the elimination or reduction of symptoms impairing the functional abilities and quality of life of the affected patients. Moreover, with symptomatic treatment the development of a secondary physical impairment due to an existing one may be avoided. Many therapeutic techniques as well as different drugs are used for the treatment of MS symptoms, but only a few of them have been investigated, especially in MS patients, and are approved by the national health authorities. Despite an overwhelming number of publications, only a few evidence-based studies exist and consensus reports are very rare, too. Therefore, it seemed necessary to develop a consensus statement on symptomatic treatment of MS comprising existing evidence-based literature as well as therapeutic experience of neurologists who have dealt with these problems over a long time. This consensus paper contains proposals for the treatment of the most common MS symptoms: disorders of motor function and coordination, of cranial nerve function, of autonomic, cognitive, and psychological functions as well as MS-related pain syndromes and epileptic seizures.

Early abnormalities of evoked potentials and future disability in patients with multiple sclerosis.

Evoked potentials (EP) have a role in making the diagnosis of multiple sclerosis (MS) but their implication for predicting the future disease course in MS is under debate. EP data of 94 MS patients examined at first presentation, and after five and ten years were retrospectively analysed. Patients were divided into two groups in relation to the prior duration of disease at the time point of first examination: group 1 patients (n=44) were first examined within two years after disease onset, and group 2 patients (n=50) at later time points. As primary measures sum scores were calculated for abnormalities of single and combined EP (visual (VEP), somatosensory (SEP), magnetic motor evoked potentials (MEP)). In patients examined early after disease onset (group 1), a significant predictive value for abnormal EP was found with MEP and SEP sum scores at first presentation correlating significantly with Expanded Disability Status Scale (EDSS) values after five years, while the VEP sum score was not. The cumulative number of abnormal MEP, SEP and VEP results also indicated higher degrees of disability (EDSS > or = 3.5) after five years. Combined pathological SEP and MEP findings at first presentation best predicted clinical disability (EDSS > or = 3.5) after five years (odds ratio 11.0). EP data and EDSS at first presentation were not significantly linked suggesting that EP abnormalities at least in part represented clinically silent lesions not mirrored by EDSS. For patients in later disease phases (group 2), no significant associations between EP data at first presentation and EDSS at five and ten years were detected. Together with clinical findings and MR imaging, combined EP data may help to identify patients at high risk of long-term clinical deterioration and guide decisions as to immunomodulatory treatment.

["Fatigue" in multiple sclerosis. Development and and validation of the "Würzburger Fatigue Inventory for MS"]. / "Fatigue" bei Multipler Sklerose. Entwicklung und Validierung des "Würzburger Erschöpfungsinventars bei MS".

BACKGROUND: Fatigue is one of the most common, yet poorly defined, disabling symptoms in patients with multiple sclerosis (MS). Several fatigue scales have been developed, but rigorous psychometric methods have not always been applied and validation was mainly based on small numbers of patients. We therefore assembled a new fatigue scale from a set of widely used scales and assessed its psychometric properties in a large sample of MS patients. PATIENTS AND METHODS: Fatigue was assessed in 158 MS patients by four published quantitative scales: the Fatigue Severity Scale (FSS), Modified Fatigue Impact Scale (MFIS), MS-specific Fatigue Severity Scale (MFSS), and Visual Analogue Scale. From these a new fatigue scale, the Würzburg Fatigue Inventory for Multiple Sclerosis (WEIMuS), was assembled. It contains 17 items with values from 0 to 4. The WEIMuS scale was validated in a subgroup of 67 patients and a control group of 68 patients. RESULTS: The MFIS and FSS but not the MFSS showed high internal consistency and split-half reliability. After applying factor analysis within the scales, fairly reliable and valid items originally found in the MFIS and FSS were selected to construct the final 17-item WEIMuS scale, which showed a high degree of reliability. In the validation study, varimax rotated factor analysis extracted two main factors corresponding to both cognitive and physical fatigue. CONCLUSION: The new, two-dimensional WEIMuS showed good psychometric properties, is easy to use, and may therefore be a useful tool for the assessment of MS-associated fatigue. Multiple sclerosis patients suffer from different types of fatigue which could be attributed to cognitive and physical fatigue. Thus, MS-associated fatigue is different from common tiredness.

Macrophage clustering as a diagnostic marker in sural nerve biopsies of patients with CIDP.

BACKGROUND: In adult patients with a slowly progressive demyelinating neuropathy, it may be difficult to distinguish between a hereditary neuropathy and chronic inflammatory demyelinating polyneuropathy (CIDP). The authors previously observed clustering of macrophages around endoneurial blood vessels in sural nerve biopsies from patients with CIDP. OBJECTIVES: To quantitate macrophage clustering around endoneurial blood vessels in CIDP vs hereditary neuropathies. METHODS: The authors studied 21 patients with CIDP, 18 patients with hereditary neuropathies, and 5 normal sural nerves. Numbers of macrophages, T-cells, and blood vessels were counted after immunohistochemical staining. The presence of three or more macrophages around one blood vessel was defined as a cluster. In a subsequent validation analysis, 65 stored biopsy specimens obtained from patients with a chronic neuropathy were re-evaluated for perivascular macrophage clustering according to criteria derived from the quantitative analysis of the first 221 biopsies in a blinded fashion. RESULTS: The percentage of endoneurial vessels with macrophage clusters was higher in CIDP than in hereditary neuropathies (CIDP median = 9.4, range 0 to 48; hereditary NP median = 0, range 0 to 7.7; p < 0.001). The evaluation of the 65 further biopsies showed that the presence of one perivascular macrophage cluster per fascicle proved to be a valid criterion to differentiate between inflammatory and other forms of neuropathy (chi2 test p = 0.0000025, sensitivity 75%, specificity 72%). CONCLUSION: The presence of clusters of macrophages around endoneurial vessels in sural nerve biopsies may serve as a useful additional marker for establishing the pathologic diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP).

Absence of reuptake of serotonin influences susceptibility to clinical autoimmune disease and neuroantigen-specific interferon-gamma production in mouse EAE.

Serotonin (5-hydroxytryptamine, 5-HT) is one of the most extensively studied neurotransmitters of the central nervous system. It also has been identified in constituents of the immune system. Therefore serotonin has been suggested to serve as a mediator of bidirectional interactions between the nervous system and the immune system. We investigated this interaction in experimental autoimmune encephalomyelitis (EAE), a well-defined animal model of autoimmune disease of the central nervous system (CNS) mimicking features of the human disease multiple sclerosis. EAE was induced by immunization with the autoantigens myelin basic protein (MBP) or the immunodominant peptide of myelin oligodendrocyte glycoprotein (MOG) spanning amino acids 35-55 (MOGp 35-55). We studied EAE in knockout (KO) mice lacking the 5-HT transporter (5-HTT) on a C57.BL/6 background, in comparison with wild-type C57.BL/6 animals. After immunization with MOGp 35-55, or with rat MBP, the disease courses of the 5-HTT knockout mice were attenuated as compared to wildtype control mice. This difference was more pronounced in female animals. To dissect potential immune mechanisms underlying this phenomenon, histological studies of the CNS and cytokine measurements in mononuclear cells from the spleens of 5-HTT KO mice and wild-type controls were performed. We found a reduction of the inflammatory infiltrate in the CNS and of the neuroantigen-specific production of IFN-gamma in splenocytes, again accompanied by a gender difference. These findings suggest a potential role of extracellular 5-HT homeostasis in the fine-tuning of neuroantigen-specific immune responses.

[Autoimmune neuropathies--current aspects of immunopathologic diagnostics and therapy]. / Immunneuropathien -- Aktuelle Aspekte der Diagnostik und Therapie.

The group of autoimmune neuropathies includes the Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuritis, multifocal motor neuropathy, neuropathies associated with monoclonal gammopathies, and vasculitic neuropathies. This educational review first addresses diagnostic pathways that facilitate more rational diagnostic decisions. Many therapies are effective for treating immune neuropathies. Unfortunately, none of the available therapies are specific. In the acute phase, glucocorticosteroids, plasmapheresis, and intravenous immunoglobulins play key roles. The list of long-term therapies includes azathioprine, cyclosporine, cyclophosphamide, and immunoglobulins. The therapeutic mechanisms involved are not clear for most of these compounds. Modern immunotherapy has to consider medical aspects, available therapeutic evidence, and long-term economic burden.

Impact of the Asp299Gly polymorphism in the toll-like receptor 4 (tlr-4) gene on disease course of multiple sclerosis.

In multiple sclerosis patients, infection is often associated with disease deterioration. Lipopolysaccharide (LPS) from gram-negative bacteria signals via the toll-like receptor 4 (TLR-4) pathway. Therefore, we investigated the role of an Asp299Gly mutation in the TLR-4 receptor in 890 MS patients with multiple sclerosis and 350 healthy controls. No association of different genotypes with MS susceptibility, MS subtypes, or disease severity was found. In vitro LPS stimulation studies showed a significantly lower proliferation of PBMCs from donors heterozygous for the Asp299Gly mutation in comparison to PBMCs from individuals with the wild-type genotype (p=0.01). However, these functional changes seem not to have any impact on the clinical presentation of MS patients with different TLR-4 genotypes.