[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE:
We aimed to report the frequency and implications of antibodies to myelin oligodendrocyte glycoprotein (MOG-ab) in adults with demyelinating syndromes suspicious for neuromyelitis optica (NMO).
Samples from 174 patients (48 NMO, 84 longitudinally extensive myelitis (LETM), 39 optic neuritis (ON), and three acute disseminated encephalomyelitis (ADEM) who presented initially with isolated LETM) were retrospectively examined for AQP4-ab and MOG-ab using cell-based assays.
MOG-ab were found in 17 (9.8%) patients, AQP4-ab in 59 (34%), and both antibodies in two (1.1%). Among the 17 patients with MOG-ab alone, seven (41%) had ON, five (29%) LETM, four (24%) NMO, and one (6%) ADEM. Compared with patients with AQP4-ab, those with MOG-ab were significantly younger (median: 27 vs. 40.5 years), without female predominance (53% vs. 90%), and the clinical course was more frequently monophasic (41% vs. 7%) with a benign outcome (median Expanded Disability Status Scale: 1.5 vs. 4.0). In eight patients with paired serum-cerebrospinal fluid (CSF) samples, five had MOG-ab in both samples and three only in serum. Antibody titres did not differ among clinical phenotypes or disease course. MOG-ab remained detectable in 12/14 patients (median follow-up: 23 months) without correlation between titres' evolution and outcome.
MOG-ab identify a subgroup of adult patients with NMO, LETM and ON that have better outcome than those associated with AQP4-ab. MOG-ab are more frequently detected in serum than CSF and the follow-up of titres does not correlate with outcome.
Multiple Sclerosis 10/2014; Oct 24. · 4.86 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Purpose
Only a fraction of patients do benefit from disease modifying treatments in RRMS and data on IVIG are controversial, it has been suggested that there is a subpopulation of patients with good clinical response to IVIG.
In the prospective, multicenter, open label, exploratory study RRMS patients receiving IVIG therapy were genotyped and several immune parameters were collected.
To distinguish between potential responders and non-responders each of the observed genotypes was combined with the corresponding scores of 65 immune parameters in a stepwise approach. Non-responders were defined as being positive for 4 or more out of 9 individual scores. Responders scored either 0 or 1, while non-responders scored between 7 and 9 (p = 1.2*10− 7).
In summary, combination of genomic and functional immune parameters allowed prospective discrimination between responders and non-responders toward IVIG therapy in this learning panel of RRMS patients and will be confirmed in a validation study.
Journal of Neuroimmunology 10/2014; · 2.79 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We have recently demonstrated the safety and tolerability of a novel therapeutic regimen employing autologous blood cells chemically coupled with seven myelin peptides to induce antigen-specific tolerance in MS (ETIMS study). The aim of the current study was an extended safety analysis to assess the effect of the ETIMS approach on antibodies to common autoantigens, the myelin peptides used and common recall antigens. None of the patients showed induction of autoantibody responses. One patient had a measurable myelin peptide-specific response at baseline, which was reduced after treatment. Total immunoglobulins and recall antibody responses showed no significant change.
Journal of Neuroimmunology 09/2014; · 2.79 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Myelin oligodendrocyte glycoprotein (MOG) antibodies have been recently described in children with acute disseminating encephalomyelitis (ADEM), but the clinical and neuroradiological characterisation of this subgroup is lacking.
[Show abstract][Hide abstract] ABSTRACT: Interactions between TIRC7 (a novel seven-transmembrane receptor on activated lymphocytes) and its ligand HLA-DR might be involved in the inflammatory process in multiple sclerosis (MS).
Methods comprised immunohistochemistry and microscopy on archival MS autopsies, proliferation-, cytokine-, and surface-staining assays using peripheral blood lymphocytes (PBLs) from MS patients and an in vitro model.
TIRC7 was expressed in brain-infiltrating lymphocytes and strongly correlated with disease activity in MS. TIRC7 expression was reduced in T cells and induced in B cells in PBLs obtained from MS patients. After ex vivo activation, T cell expression of TIRC7 was restored in patients with active MS disease. The interaction of TIRC7(+) T lymphocytes with cells expressing HLA-DR on their surface led to T cell proliferation and activation whereas an anti-TIRC7 mAb preventing interactions with its ligand inhibited proliferation and Th1 and Th17 cytokine expression in T cells obtained from MS patients and in myelin basic protein-specific T cell clone.
Our findings suggest that TIRC7 is involved in inflammation in MS and anti-TIRC7 mAb can prevent immune activation via selective inhibition of Th1- and Th17-associated cytokine expression. This targeting approach may become a novel treatment option for MS.
[Show abstract][Hide abstract] ABSTRACT: Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system (CNS), which is characterized by the presence of pathogenic serum autoantibodies against aquaporin 4 (AQP4) in the vast majority of patients. The contribution of T cells to the formation of astrocyte destructive lesions is currently unclear. However, active human NMO lesions contain CD4+ T-lymphocytes expressing the activation marker Ox40, and that the expression was more profound compared to that seen in MS lesions of comparable activity. Therefore, we analyzed the role of T-cell activation within the CNS in the initiation of NMO lesions in an experimental model of co-transfer of different encephalitogenic T-cells and human AQP4 antibody containing NMO immunoglobulin (NMO IgG). We further studied the expression of the T-cell activation marker Ox40 in NMO and multiple sclerosis lesions in different stages of activity.
All encephalitogenic T-cell lines used in our experiments induced brain inflammation with a comparable extent of blood brain barrier damage, allowing human NMO IgG to penetrate into the brain and spinal cord tissue. However, astrocyte destructive NMO lesions were only seen with T-cells, which showed signs of activation in the lesions. T-cell activation was reflected by the expression of the activation marker Ox40 and pronounced production of gamma-IFN, which was able to increase the production of complement proteins and of the Fc gamma III receptor (Fcgr3) and decreased production of complement inhibitory protein Factor H in microglia.
Our data indicate that local activation of T-cells provide an inflammatory environment in the CNS, which allows AQP4 auto-antibodies to induce astrocyte destructive NMO-like lesions.
[Show abstract][Hide abstract] ABSTRACT: The recent detection of aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) autoantibodies in acquired inflammatory demyelinating diseases, such as neuromyelitis optica, or acute disseminated encephalomyelitis, and multiple sclerosis, in children strongly indicates that B-cell-dependent mechanisms contribute to the pathogenesis. This review aims to give an overview of the role of autoantibodies in inflammatory demyelinating pediatric diseases, with a focus on antibodies to AQP4 and MOG.
[Show abstract][Hide abstract] ABSTRACT: Autoantibodies targeting conformationally intact myelin oligodendrocyte glycoprotein (MOG) are found in different inflammatory diseases of the CNS, but their antigenic epitopes have not been mapped. We expressed mutants of MOG on human HeLa cells and analyzed sera from 111 patients (104 children, 7 adults) who recognized cell-bound human MOG, but had different diseases, including acute disseminated encephalomyelitis (ADEM), one episode of transverse myelitis or optic neuritis, multiple sclerosis (MS), anti-aquaporin-4 (AQP4)-negative neuromyelitis optica (NMO), and chronic relapsing inflammatory optic neuritis (CRION). We obtained insight into the recognition of epitopes in 98 patients. All epitopes identified were located at loops connecting the β strands of MOG. The most frequently recognized MOG epitope was revealed by the P42S mutation positioned in the CC'-loop. Overall, we distinguished seven epitope patterns, including the one mainly recognized by mouse mAbs. In half of the patients, the anti-MOG response was directed to a single epitope. The epitope specificity was not linked to certain disease entities. Longitudinal analysis of 11 patients for up to 5 y indicated constant epitope recognition without evidence for intramolecular epitope spreading. Patients who rapidly lost their anti-MOG IgG still generated a long-lasting IgG response to vaccines, indicating that their loss of anti-MOG reactivity did not reflect a general lack of capacity for long-standing IgG responses. The majority of human anti-MOG Abs did not recognize rodent MOG, which has implications for animal studies. Our findings might assist in future detection of potential mimotopes and pave the way to Ag-specific depletion.
The Journal of Immunology 09/2013; · 5.36 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Myelin oligodendrocyte glycoprotein (MOG) has been identified as a target of demyelinating autoantibodies in animal models of inflammatory demyelinating diseases of the CNS, such as multiple sclerosis (MS). Numerous studies have aimed to establish a role for MOG antibodies in patients with MS, although the results have been controversial. Cell-based immunoassays using MOG expressed in mammalian cells have demonstrated the presence of high-titre MOG antibodies in paediatric patients with acute disseminated encephalomyelitis, MS, aquaporin-4-seronegative neuromyelitis optica, or isolated optic neuritis or transverse myelitis, but only rarely in adults with these disorders. These studies indicate that MOG antibodies could be associated with a broad spectrum of acquired human CNS demyelinating diseases. This Review article discusses the current literature on MOG antibodies, their potential clinical relevance, and their role in the pathogenesis of MOG antibody-associated demyelinating disorders.
[Show abstract][Hide abstract] ABSTRACT: Background: Neuromyelitis optica (NMO) is a severe, disabling disease of the central nervous system (CNS) characterized by the formation of astrocyte-destructive, neutrophil-dominated inflammatory lesions in the spinal cord and optic nerves. These lesions are initiated by the binding of pathogenic aquaporin 4 (AQP4)-specific autoantibodies to astrocytes and subsequent complement-mediated lysis of these cells. Typically, these lesions form in a setting of CNS inflammation, where the blood–brain barrier is open for the entry of antibodies and complement. However, it remained unclear to which extent pro-inflammatory cytokines and chemokines contribute to the formation of NMO lesions. To specifically address this question, we injected the cytokines interleukin-1 beta, tumor necrosis factor alpha, interleukin-6, interferon gamma and the chemokine CXCL2 into the striatum of NMO-IgG seropositive rats and analyzed the tissue 24 hours later by immunohistochemistry. Results: All injected cytokines and chemokines led to profound leakage of immunoglobulins into the injected hemisphere, but only interleukin-1 beta induced the formation of perivascular, neutrophil-infiltrated lesions with AQP4 loss and complement-mediated astrocyte destruction distant from the needle tract. Treatment of rat brain endothelial cells with interleukin-1 beta, but not with any other cytokine or chemokine applied at the same concentration and over the same period of time, caused profound upregulation of granulocyte-recruiting and supporting molecules. Injection of interleukin-1 beta caused higher numbers of blood vessels with perivascular, cellular C1q reactivity than any other cytokine tested. Finally, the screening of a large sample of CNS lesions from NMO and multiple sclerosis patients revealed large numbers of interleukin-1 beta-reactive macrophages/activated microglial cells in active NMO lesions but not in MS lesions with comparable lesion activity and location. Conclusions: Our data strongly suggest that interleukin-1 beta released in NMO lesions and interleukin-1 beta-induced production/accumulation of complement factors (like C1q) facilitate neutrophil entry and BBB breakdown in the vicinity of NMO lesions, and might thus be an important secondary factor for lesion formation, possibly by paving the ground for rapid lesion growth and amplified immune cell recruitment to this site.
[Show abstract][Hide abstract] ABSTRACT: The aim of this observational study was to analyze clinical and immunological effects of rituximab treatment in neuromyelitis optica (NMO) and longitudinally extensive transverse myelitis (LETM) patients. We report on four NMO and two recurrent LETM patients who were treated with rituximab. Overall, B-cell depletion resulted in profound clinical stabilization in all patients. Rituximab did not affect titers of antibodies to aquaporin-4 (AQP4-IgG) and myelin oligodendrocyte glycoprotein, immunoglobulin (Ig) isotypes and IgG subtype distribution, even after long-term B-cell depletion. Relapses were not associated with re-emerging B-cells, serum levels of B-cell activating factor (BAFF) or AQP4-IgG titers. BAFF serum levels increased following rituximab treatment.
Journal of the neurological sciences 03/2013; · 2.32 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Nerve growth factor (NGF), a member of the neurotrophin family, is responsible for the maintenance and survival of cholinergic neurons in the basal forebrain. The degeneration of cholinergic neurons and reduced acetycholine levels are hallmarks of Alzheimer's disease (AD) as well as associated with learning and memory deficits. Thus far, NGF has proven the most potent neuroprotective molecule against cholinergic neurodegeneration. However, delivery of this factor into the brain remains difficult. Recent studies have begun to elucidate the potential use of monocytes as vehicles for therapeutic delivery into the brain. In this study, we employed different transfection and transduction methods to generate NGF-secreting primary rat monocytes. Specifically, we compared five methods for generating NGF-secreting monocytes: (1) cationic lipid-mediated transfection (Effectene and FuGene), (2) classical electroporation, (3) nucleofection, (4) protein delivery (Bioporter) and (5) lentiviral vectors. Here, we report that classical transfection methods (lipid-mediated transfection, electroporation, nucleofection) are inefficient tools for proper gene transfer into primary rat monocytes. We demonstrate that lentiviral infection and Bioporter can successfully transduce/load primary rat monocytes and produce effective NGF secretion. Furthermore, our results indicate that NGF is bioactive and that Bioporter-loaded monocytes do not appear to exhibit any functional disruptions (i.e. in their ability to differentiate and phagocytose beta-amyloid). Taken together, our results show that primary monocytes can be effectively loaded or transduced with NGF and provides information on the most effective method for generating NGF-secreting primary rat monocytes. This study also provides a basis for further development of primary monocytes as therapeutic delivery vehicles to the diseased AD brain.
Journal of immunological methods 03/2013; · 2.35 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In 2008 the Austrian Task Force for Neuromyelitis Optica (NMO) started a nation-wide network for information exchange and multi-centre collaboration. Their aim was to detect all patients with NMO or NMO spectrum disorders (NMO-SD) in Austria and to analyse their disease courses and response to treatment.
(1) As of March 2008, 1957 serum samples (of 1557 patients) have been tested with an established cell based immunofluorescence aquaporin-4 antibody (AQP4-ab) assay with a high sensitivity and specificity (both >95%). All tests were performed in a single reference laboratory (Clinical Dept. of Neurology of the Innsbruck Medical University). (2) A nation-wide survey with several calls for participation (via email newsletters, articles in the official journal of the Austrian Society of Neurology, and workshops) was initiated in 2008. All collected data will be presented in a way that allows that every individual patient can be traced back in order to ensure transparency and to avoid any data distortion in future meta-analyses. The careful and detailed presentation allows the visualization and comparison of the different disease courses in real time span. Failure and response to treatment are made visible at one glance. Database closure was 31 December 2011. All co-operators were offered co-authorship.
All 71 NMO- or NMO-SD patients with AQP4-ab positivity (age range 12.3 to 79.6 years) were analysed in detail. Sex ratio (m:f = 1:7) and the proportion of patients without oligoclonal bands in cerebrospinal fluid (86.6%) were in line with previously published results. All identified patients were Caucasians.
A nationwide collaboration amongst Austrian neurologists with good network communications made it possible to establish a database of 71 AQP4-ab positive patients with NMO/NMO-SD. This database is presented in detail and provides the basis for further studies and international cooperation in order to investigate this rare disease.
PLoS ONE 01/2013; 8(11):e79649. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Recently we showed that antibodies to myelin oligodendrocyte glycoprotein (MOG) can be found in aquaporin-4 (AQP4)-immunoglobulin (IgG) seronegative pediatric and adult patients with definite and high-risk neuromyelitis optica (NMO). OBJECTIVE: The purpose of this study was to describe the clinical characteristics and temporal dynamics of MOG-IgG in AQP4-IgG seronegative pediatric patients presenting with definite NMO. METHODS: Children with definite NMO who were referred for further testing of serum antibodies for AQP4 and MOG with a cell-based assay were included in this study. Clinical disease course, cerebrospinal fluid and magnetic resonance imaging (MRI) studies of these patients were reviewed. RESULTS: Between 2008 and 2012 eight children who fulfilled the diagnostic criteria of definite NMO were recruited. Two children with definite NMO tested positive for AQP4-IgG but were negative for MOG-IgG antibodies. Three children had an absence of AQP4-IgG and MOG-IgG antibodies. Three children with definite NMO had high titers of serum MOG-IgG antibodies (≥1: 160), but no AQP4-directed humoral immune response. Longitudinal analysis of serum samples of the latter three children showed persisting high MOG-IgG titers over time. CONCLUSION: Pediatric patients presenting with clinical symptoms and MRI findings highly suggestive of NMO but with high and persisting MOG-IgG antibody titers are most likely to represent a distinct subgroup of acute demyelinating diseases with important clinical and therapeutic implications.
[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE: Biomarkers are required for the diagnosis and monitoring of disease progression in Parkinson disease (PD). To date, most studies have concentrated on α-synuclein (α-Syn), a protein involved in Parkinson disease pathogenesis, as a potential biomarker, with inconsistent outcomes. Recently, naturally occurring autoantibodies against α-Syn (α-Syn-nAbs) have been detected in the serum of patients with PD. They represent a putative diagnostic marker for PD. METHODS: We established and validated an ELISA to quantify α-Syn-nAbs in serum samples. We analyzed serum samples from 62 patients with PD, 46 healthy controls (HC), and 42 patients with Alzheimer disease (AD) using this newly established ELISA. Additionally, serum levels of endogenous α-Syn were measured. RESULTS: There was a significant difference in α-Syn-nAbs levels between the investigated groups (p = 0.005; Kruskal-Wallis test). Levels of α-Syn-nAbs were significantly lower in patients with PD compared to HC (p < 0.05; Dunn multiple comparison post hoc test) or patients with AD (p < 0.05). Furthermore, we detected no difference between patients with AD and HC. The sensitivity and specificity of the assay for patients with PD vs HC were 85% and 25%, respectively. The α-Syn-nAbs levels did not correlate with age, Hoehn & Yahr status, or duration of disease. Endogenous α-Syn had no influence on α-Syn-nAbs levels in sera. CONCLUSIONS: Using a well-validated assay, we detected reduced α-Syn-nAbs levels in patients with PD compared to patients with AD and HC. The assay did not achieve criteria for use as a diagnostic tool to reliably distinguish PD from HC. Further studies are needed to assess α-Syn-nAbs as a biomarker in PD.
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Microarray technology may offer a new opportunity to gain insight into disease-specific global protein expression profiles. The present study was performed to apply a serum antibody microarray to screen for differentially regulated cytokines in Parkinson's disease (PD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS). RESULTS: Serum samples were obtained from patients with clinical diagnoses of PD (n = 117), MSA (n = 31) and PSP/CBS (n = 38) and 99 controls. Cytokine profiles of sera from patients and controls were analyzed with a semiquantitative human antibody array for 174 cytokines and the expression of 12 cytokines was found to be significantly altered. In a next step, results from the microarray experiment were individually validated by different immunoassays. Immunoassay validation confirmed a significant increase of median PDGF-BB levels in patients with PSP/CBS, MSA and PD and a decrease of median prolactin levels in PD. However, neither PDGF-BB nor prolactin were specific biomarkers to discriminate PSP/CBS, MSA, PD and controls. CONCLUSIONS: In our unbiased cytokine array based screening approach and validation by a different immunoassay only two of 174 cytokines were significantly altered between patients and controls.