Extensive research over the last decades basically failed to identify a common cause of noninfectious inflammatory central nervous system (CNS) demyelinating disease. To a great extent, this may ...reflect that the group of inflammatory CNS demyelinating disorders likely contains multiple pathogenetically distinct disease entities. Indeed, the greatest success so far in deciphering the pathogenesis of a CNS demyelinating disorder resulted from the discovery of anti-aquaporin (AQP)-4 antibodies (ab), which allowed progressive delineation of neuromyelitis optica (NMO), formerly considered a variant of the most common CNS demyelinating disorder, multiple sclerosis (MS), as a distinct disease. Nowadays, AQP-4+ NMO is considered an autoimmune astrocytopathy, in which CNS demyelination occurs only as a consequence of a primary destruction of astrocytes. Delineating these patients concomitantly revealed that not all patients presenting with clinically NMO-suggestive disease phenotype express AQP-4 ab, which created the pathogenetically undefined category of NMO spectrum disorders (NMOSD). Recent investigations discovered that a subgroup of these AQP-4– NMOSD patients produce an ab response against myelin oligodendrocyte glycoprotein (MOG), a molecule expressed on the outer lamella of the myelin sheath. Using pathophysiologically meaningful cell-based assays, this humoral response is extremely rare in adult MS and absent in classical AQP-4+ NMO, sharply differentiating the evolving group from both established disorders. In this review, we summarize available clinical, immunological and histopathological data on patients with MOG+ CNS demyelinating disease. By comparing this clearly distinct cohort to AQP-4+ NMO as well as MS, we propose that MOG+ CNS demyelinating disease represents a distinct novel disease entity. In addition to its diagnostic value, we furthermore provide mechanistic insight on how this peripheral anti-MOG ab response may be of pathogenetic relevance in triggering acute flares of inflammatory CNS demyelination.
The immune reconstitution inflammatory syndrome can be a serious complication of immune reversal in the treatment of progressive multifocal leukoencephalopathy. A new potential treatment for IRIS is ...described in this letter.
To the Editor:
The immune reconstitution inflammatory syndrome (IRIS) can be a serious complication in immunocompromised patients in whom progressive multifocal leukoencephalopathy (PML) has developed. IRIS occurs in such patients when their immunocompromised state reverses.
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Although restored immune surveillance is vital for clearing the JC virus that causes PML, improved management strategies for IRIS are needed because of its potential for considerable complications and death. The common, though unproven, use of glucocorticoids to treat IRIS may limit JC viral clearance.
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Because of the indirect implication of chemokine receptor 5–positive (CCR5+) T cells in IRIS pathophysiology,
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we used the small-molecule CCR5 . . .
Progressive multifocal leukoencephalopathy (PML) is an opportunistic infection of the CNS caused by the JC virus, which infects white and grey matter cells and leads to irreversible demyelination and ...neuroaxonal damage. Brain MRI, in addition to the clinical presentation and demonstration of JC virus DNA either in the CSF or by histopathology, is an important tool in the detection of PML. In clinical practice, standard MRI pulse sequences are utilized for screening, diagnosis and monitoring of PML, but validated imaging-based outcome measures for use in prospective, interventional clinical trials for PML have yet to be established. We review the existing literature regarding the use of MRI and PET in PML and discuss the implications of PML histopathology for neuroradiology. MRI not only demonstrates the localization and extent of PML lesions, but also mirrors the tissue destruction, ongoing viral spread, and resulting inflammation. Finally, we explore the potential for imaging measures to serve as an outcome in PML clinical trials and provide recommendations for current and future imaging outcome measure development in this area.
The antigen-specific activation of pathogenic T cells is considered essential in the initiation and maintenance of multiple sclerosis (MS). The site of activation, the differential involvement of ...CD4+, and CD8+ T cells, their functional phenotype, and specificity, are important aspects to understand MS pathogenesis. The analysis of clonal expansions of brain-infiltrating T cells may reveal local antigen-driven activation or specific brain homing and allow the identification of putatively pathogenic T cells. We used high-throughput T cell receptor β-chain variable gene (TRBV) sequencing (-seq) of genomic (g)DNA, which reflects the quantity and diversity of the TRBV repertoire, to characterize three white matter demyelinating lesions with different location and inflammatory activity, and paired peripheral blood memory CD4+ and CD8+ T cell pools from a secondary progressive (SP)MS patient. Our results revealed an important sharing of clonally expanded T cells with identical TRBV sequence (clonotypes) across MS lesions independently of their proximity or inflammatory activity. Comparison with circulating T cells showed that the most frequent brain-infiltrating CD8+, but not CD4+ clonotypes were also those with highest frequency in the peripheral blood, indicating clonal expansion inside the brain or specific brain homing of CD4+ but not CD8+ T cells. Parallel TRBV-seq of complementary (c)DNA that reflects the activation status of the cells, revealed differences between lesions regarding inflammatory activity and appears to facilitate the identification of putatively pathogenic T cells in active lesions. Approaches to identify pathogenic T cells in brain lesions using TRBV-seq may benefit from focusing on lesions with high inflammatory activity and from combining gDNA and cDNA sequencing.
Background:
Histopathological studies have revealed four different immunopathological patterns of lesion pathology in early multiple sclerosis (MS). Pattern II MS is characterised by immunoglobulin ...and complement deposition in addition to T-cell and macrophage infiltration and is more likely to respond to plasma exchange therapy, suggesting a contribution of autoantibodies.
Objective:
To assess the frequency of anti-myelin oligodendrocyte glycoprotein (MOG), anti-M1-aquaporin-4 (AQP4), anti-M23-AQP4, anti-N-methyl-d-aspartate-type glutamate receptors (NMDAR) and 25 other anti-neural antibodies in pattern II MS.
Methods:
Thirty-nine serum samples from patients with MS who had undergone brain biopsy (n = 24; including 13 from patients with pattern II MS) and from histopathologically non-classified MS patients (n = 15) were tested for anti-MOG, anti-M1-AQP4, anti-M23-AQP4, anti-NMDAR, anti-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor-type glutamate receptors (AMPAR), anti-gamma-aminobutyric acid receptors (GABABR), anti-leucine-rich, glioma-activated protein 1 (LGI1), anti-contactin-associated protein 2 (CASPR2), anti-dipeptidyl-peptidase-like protein-6 (DPPX), anti-Tr/Delta/notch-like epidermal growth factor–related receptor (DNER), anti-Hu, anti-Yo, anti-Ri, anti-Ma1/Ma2, anti-CV2/collapsin response mediator protein 5 (CRMP5), anti-glutamic acid decarboxylase (GAD), anti-amphiphysin, anti-Ca/RhoGTPase-activating protein 26 (ARHGAP26), anti-Sj/inositol-1,4,5-trisphosphate receptor 1 (ITPR1), anti-Homer3, anti-carbonic anhydrase–related protein (CARPVIII), anti-protein kinase gamma (PKCgamma), anti-glutamate receptor delta 2 (GluRdelta2), anti-metabotropic glutamate receptor 1 (mGluR1) and anti-mGluR5, as well as for anti-glial nuclei antibodies (AGNA) and Purkinje cell antibody 2 (PCA2).
Results:
Antibodies to MOG belonging to the complement-activating immunoglobulin G1 (IgG1) subclass were detected in a patient with pattern II MS. Detailed brain biopsy findings are shown.
Conclusion:
This is the largest study on established anti-neural antibodies performed in MS so far. MOG-IgG may play a role in a small percentage of patients diagnosed with pattern II MS.
The diagnostic and pathophysiological relevance of antibodies to aquaporin-4 (AQP4-Ab) in patients with neuromyelitis optica spectrum disorders (NMOSD) has been intensively studied. However, little ...is known so far about the clinical impact of AQP4-Ab seropositivity.
To analyse systematically the clinical and paraclinical features associated with NMO spectrum disorders in Caucasians in a stratified fashion according to the patients' AQP4-Ab serostatus.
Retrospective study of 175 Caucasian patients (AQP4-Ab positive in 78.3%).
Seropositive patients were found to be predominantly female (p < 0.0003), to more often have signs of co-existing autoimmunity (p < 0.00001), and to experience more severe clinical attacks. A visual acuity of ≤ 0.1 during acute optic neuritis (ON) attacks was more frequent among seropositives (p < 0.002). Similarly, motor symptoms were more common in seropositive patients, the median Medical Research Council scale (MRC) grade worse, and MRC grades ≤ 2 more frequent, in particular if patients met the 2006 revised criteria (p < 0.005, p < 0.006 and p < 0.01, respectively), the total spinal cord lesion load was higher (p < 0.006), and lesions ≥ 6 vertebral segments as well as entire spinal cord involvement more frequent (p < 0.003 and p < 0.043). By contrast, bilateral ON at onset was more common in seronegatives (p < 0.007), as was simultaneous ON and myelitis (p < 0.001); accordingly, the time to diagnosis of NMO was shorter in the seronegative group (p < 0.029). The course of disease was more often monophasic in seronegatives (p < 0.008). Seropositives and seronegatives did not differ significantly with regard to age at onset, time to relapse, annualized relapse rates, outcome from relapse (complete, partial, no recovery), annualized EDSS increase, mortality rate, supratentorial brain lesions, brainstem lesions, history of carcinoma, frequency of preceding infections, oligoclonal bands, or CSF pleocytosis. Both the time to relapse and the time to diagnosis was longer if the disease started with ON (p < 0.002 and p < 0.013). Motor symptoms or tetraparesis at first myelitis and > 1 myelitis attacks in the first year were identified as possible predictors of a worse outcome.
This study provides an overview of the clinical and paraclinical features of NMOSD in Caucasians and demonstrates a number of distinct disease characteristics in seropositive and seronegative patients.
OBJECTIVES:To evaluate the presence of antibodies to conformation-intact myelin oligodendrocyte glycoprotein (MOG) in a subgroup of adult patients with clinically definite multiple sclerosis (MS) ...preselected for a specific clinical phenotype including severe spinal cord, optic nerve, and brainstem involvement.
METHODS:Antibodies to MOG were investigated using a cell-based assay in 3 groups of patients104 preselected patients with MS (group 1), 55 age- and sex-matched, otherwise unselected patients with MS (group 2), and in 22 brain-biopsied patients with demyelinating diseases of the CNS (n = 19 with MS), 4 of whom classified as MS type II (group 3). Recognized epitopes were identified with mutated variants of MOG.
RESULTS:Antibodies to MOG were found in about 5% (5/104) of preselected adult patients with MS. In contrast, in groups 2 and 3, none of the patients tested positive for MOG antibodies. Patients with MS with antibodies to MOG predominantly manifested with concomitant severe brainstem and spinal cord involvement and had a severe disease course with high relapse rates and failure to several disease-modifying therapies. Three of them had been treated with plasma exchange with a favorable response. All anti-MOG–positive patients with MS showed typical MS lesions on brain MRI. Longitudinal analysis up to 9 years revealed fluctuations and reappearance of anti-MOG reactivity. Epitope mapping indicated interindividual heterogeneity, yet intraindividual stability of the antibody response.
CONCLUSIONS:Antibodies to MOG can be found in a distinct subgroup of adult MS with a specific clinical phenotype and may indicate disease heterogeneity.
Background:
Daclizumab is a monoclonal antibody that binds the high-affinity interleukin-2 receptor and was approved for the treatment of relapsing multiple sclerosis. Due to severe inflammatory ...brain disorders, the approval was suspended in March 2018.
Objective and Methods:
This retrospective cohort study summarizes clinical, laboratory, radiological, and histological findings of seven patients who developed meningo-/encephalitis after daclizumab therapy.
Results:
Patients presented with encephalitis and/or meningitis and suffered from systemic symptoms such as fever (5/7), exanthema (5/7), or gastrointestinal symptoms (4/7). Secondary autoimmune diseases developed. Blood analysis revealed an increase in eosinophils (5/7). Six patients fulfilled the diagnostic criteria for a drug reaction with eosinophilia and systemic symptoms (DRESS). Magnetic resonance imaging (MRI) showed multiple contrast-enhancing lesions, and enhancement of the ependyma (6/7), meninges (5/7), cranial or spinal nerves (2/7), and a vasculitic pattern (3/7). Histology revealed a pronounced inflammatory infiltrate consisting of lymphocytes, plasma cells and eosinophils, and densely infiltrated vessels. Most patients showed an insufficient therapeutic response and a high disability at last follow-up (median Expanded Disability Status Scale (EDSS) 8). Two patients died.
Conclusion:
Meningoencephalitis and DRESS may occur with daclizumab therapy. This potential lethal side effect is characterized by a dysregulated immune response. Our findings underline the importance of postmarketing drug surveillance.
Axonal loss is a major component of the pathology of multiple sclerosis (MS) and the morphological basis of permanent clinical disability. It occurs in demyelinating plaques but also in the so‐called ...normal‐appearing white matter (NAWM). However, the contribution of Wallerian degeneration to axonal pathology is not known. Here, we analyzed the extent of Wallerian degeneration and axonal pathology in periplaque white matter (PPWM) and lesions in early multiple sclerosis biopsy tissue from 63 MS patients. Wallerian degeneration was visualized using an antibody against the neuropeptide Y receptor Y1 (NPY‐Y1R). The number of SMI‐32‐positive axons with non‐phosphorylated neurofilaments was significantly higher in both PPWM and plaques compared to control white matter. APP‐positive, acutely damaged axons were found in significantly higher numbers in plaques compared to PPWM. Strikingly, the number of NPY‐Y1R‐positive axons undergoing Wallerian degeneration was significantly higher in PPWM and plaques than in control WM. NPY‐Y1R‐positive axons in PPWM were strongly correlated to those in the lesions. Our results show that Wallerian degeneration is a major component of axonal pathology in the periplaque white matter in early MS. It may contribute to radiological changes observed in early MS and most likely plays a major role in the development of disability.
Multiple sclerosis (MS) is an autoimmune disorder characterized by chronic inflammation, demyelination, and neuronal damage. During autoimmunity, cytokines are important mediators of the ...inflammation. In this line, interleukin-27 (IL-27) modulates inflammation and can be produced directly at inflammatory sites such as in the joints during rheumatoid arthritis or in the central nervous system (CNS) during MS. While in animal models of MS, treatment with IL-27 decreases the disease severity, its role in humans is not clearly established and it is not known if IL-27 could be detected in the cerebrospinal fluid (CSF) of MS patients.
In this study, we measured IL-27 levels using a quantitative enzyme-linked immunosorbent assay in CSF of patients with relapsing remitting multiple sclerosis (RRMS), isolated optic neuritis (ON) and non-inflammatory neurological disease (NIND) as well as in the sera of healthy donors (HD) and RRMS patients undergoing different disease modifying treatments. We further confirmed by immunohistology of patient biopsies the identity of IL-27 producing cells in the brain of active MS lesions.
We observed that IL-27 levels are increased in the CSF but not in the sera of RRMS compared to HD. We confirmed that IL-27 is expressed in active MS plaques by astrocytes of MS patients.
Our results point toward a local secretion of IL-27 in the CNS that is increased during autoimmune processes. We propose that local production of IL-27 could sign the induction of a regulatory response that promotes inflammation's resolution. The effect of new immunomodulatory therapies on cerebral IL-27 production could be used to understand the biology of IL-27 in MS disease.