Antibody-related Disease Research Articles

Bilateral pontine brachium lesions in one autoantibodies directed against MOG positive patient: A case report.

Myelin oligodendrocyte glycoprotein (MOG) antibody-related disease is a relatively recent entity in inflammatory demyelinating disease. Its clinical presentation varies in severity and the lack of specific imaging features makes it easy to misdiagnose. We now report the case of a MOG antibody-positive patient who presented with diplopia and dizziness, and whose brain magnetic resonance imaging (MRI) showed abnormal signals in the bilateral pontine brachium. A previously healthy 52-year-old woman presented with diplopia and dizziness, and was hospitalized 4 days after onset. Brain MRI demonstrated abnormal hyperintense signals in the bilateral pontine brachium on T2-weighted fluid attenuated inversion recovery imaging. MRI enhancement showed abnormal enhancement foci in bilateral pontine brachium and pons. Cerebrospinal fluid examination showed Oligoclonal IgG bands were negative. The IgG index was normal, and serum aquaporin-4 antibody was negative, while serum MOG-Ab was positive (1:100). In conjunction with a positive serum MOG antibody and exclusion of other diseases, diagnosis of MOG antibody-related disease was made. Intravenous methylprednisolone followed by oral corticosteroids. Symptoms resolved completely. At 4-month follow-up. Follow-up after 4 months showed disappearance of the abnormal signal in the left pontine brachium and diminution of abnormal high signal in the right compared to the previous one, and there was no recurrence 1 year after the onset of the disease. If brain MRI indicating bilateral, multiple, and diffuse abnormal signals in the pontine brachium, and a discrepancy between the clinical symptoms and the imaging severity, a diagnosis of demyelinating disease should be considered highly probable. In such cases, anti-MOG antibody testing is essential for further defining the etiology. The clinical phenotype and imaging manifestations of MOG antibody-positive brainstem encephalitis may lack sufficient specificity to be readily identifiable. Timely diagnosis and early glucocorticoid therapy are beneficial in improving prognosis and preventing recurrence.

381 BiP knockdown decreases antibody production in malignant and non-malignant plasma cells

OBJECTIVES/GOALS: Numerous diseases, including AL amyloidosis, are due to expression of aberrant antibodies. Significant effort has gone into plasma cell toxic therapies with varying degrees of success, but no therapies preventing antibody synthesis have been developed. The goal of this study is to assess BiP targeting to prevent antibody secretion in plasma cells. METHODS/STUDY POPULATION: Using 4 multiple myeloma cell lines (KMS11, RPMI8226, ANBL-6, U266), we knocked down BiP expression with RnaseH dependent siRNA or subA toxin, a bacterial toxin that specifically cleaves BiP, and measured changes in unfolded protein and intracellular light chains by flow cytometry during drug induced ER stress created by the intracellular calcium depleting agent thapsigargin. BiP is the master regulator of the unfolded protein response (UPR), an ER stress pathway important for protein folding. BiP is also an ER resident protein folding chaperone important for proper antibody folding. We hypothesized that BiP downregulation will lead to decreased folded antibody in the cell, increased unfolded antibody and constitutive activation of the UPR. RESULTS/ANTICIPATED RESULTS: 1 to 4 hours after treatment with thapsigargin plus siRNA against BiP, levels of BiP are significantly decreased. The levels of intracellular light chains decrease, and the level of unfolded protein within the cells increases dramatically. Interestingly, in alignment with the UPR literature, 24 hours post treatment, these levels have normalized again in surviving cells. SubA treatment increased BiP expression by 4 hours, contrary to our hypothesis, and minimally increased unfolded proteins and minimally decreased intracellular light chains. We expect that further functional testing of antibody secretion by ELIspot assays will show decreased secretion of antibody with BiP siRNA treatment. Combination therapies with other UPR stressing agents may act synergistically to affect antibody production. DISCUSSION/SIGNIFICANCE: BiP knockdown reduces antibodies and boosts unfolded proteins. SubA toxin ineffectiveness likely stems from increased BiP due to feedback loops. Combining anti-BiP treatments with UPR stressing drugs like bortezomib may halt antibody synthesis and induce cell death. These findings support BiP as a viable drug target for antibody-related diseases.

Less common phenotypes of myelin oligodendrocyte glycoprotein antibody-related diseases in children deserve more attention

BackgroundTo facilitate the identification of less common clinical phenotypes of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) in children.MethodsWe retrospectively reviewed medical records of 236 patients with MOGAD. The following phenotypes were considered to be typical for MOGAD: ADEM, ON, TM, and NMOSD. Less common onset clinical phenotypes were screened out; their clinical and magnetic resonance imaging (MRI), diagnosis, treatment, and prognosis were summarized and analyzed.Results16 cases (6.8%) presented as cortical encephalitis, with convulsions, headache, and fever as the main symptoms. 15 cases were misdiagnosed in the early period. 13 cases (5.5%) showed the overlapping syndrome of MOGAD and anti-N-methyl-D aspartate receptor encephalitis (MNOS), with seizures (92.3%) being the most common clinical symptom. 11 cases (84.6%) showed relapses. The cerebral leukodystrophy-like phenotype was present in seven cases (3.0%), with a recurrence rate of 50%. Isolated seizures without any findings on MRI phenotype was present in three cases (1.3%), with the only clinical symptom being seizures of focal origin. Three cases (1.3%) of aseptic meningitis phenotype presented with prolonged fever.Conclusion40/236 (16.9%) of children with MOGAD had less common phenotypes. Less common clinical phenotypes of pediatric MOGAD are susceptible to misdiagnosis and deserve more attention.ImpactThis is the first comprehensive analysis and summary of all less commonl clinical phenotypes of MOGAD in children, while previous studies have only focused on a specific phenotype or case reports.We analyzed the characteristics of MOGAD in children and further revealed the reasons why these less common clinical phenotypes are prone to misdiagnosis and deserve more attention.Our research on treatment has shown that early detection of MOG antibodies and early treatment are of great significance for improving the prognosis of these patients.

Classification of Myelin Oligodendrocyte Glycoprotein Antibody-Related Disease and Its Mimicking Acute Demyelinating Syndromes in Children Using MRI-Based Radiomics: From Lesion to Subject

To develop MRI-based radiomics models from the lesion level to the subject level and assess their value for differentiating myelin oligodendrocyte glycoprotein antibody-related disease (MOGAD) from non-MOGAD acute demyelinating syndromes in pediatrics. 66 MOGAD and 66 non-MOGAD children were assigned to the training set (36/35), internal test set (14/16), and external test set (16/15), respectively. At the lesion level, five single-sequence models were developed alongside a fusion model (combining these five sequences). The radiomics features of each lesion were quantified as the lesion-level radscore (LRS) using the best-performing model. Subsequently, a lesion-typing function was employed to classify lesions into two types (MOGAD-like or non-MOGAD-like), and the average LRS of the predominant type lesions in each subject was considered as the subject-level radscore (SRS). Based on SRS, a subject-level model was established and compared toboth clinical models and radiologists' assessments. At the lesion level, the fusion model outperformed the five single-sequence models in distinguishing MOGAD and non-MOGAD lesions (0.867 and 0.810 ofarea under the curve[AUC] in internal and external testing, respectively). At the subject level, the SRS model showed superior performance (0.844 and 0.846 of AUC in internal and external testing, respectively) compared to clinical models and radiologists' assessments for distinguishing MOGAD and non-MOGAD. MRI-based radiomics models have potential clinical value for identifying MOGAD from non-MOGAD. The fusion model and SRS model can distinguish between MOGAD and non-MOGAD at the lesion level and subject level, respectively, providing a differential diagnosis method for these two diseases.

Peripheral nervous system involvement accompanies central nervous system involvement in anti-glial fibrillary acidic protein (GFAP) antibody-related disease.

Glial fibrillary acidic protein (GFAP) is expressed by astrocytes in the central nervous system (CNS), but also by immature and regenerative Schwann cells in the peripheral nervous system (PNS). GFAP antibodies (GFAP-Abs) in cerebrospinal fluid (CSF) have been mainly described in patients with meningoencephalomyelitis. We aimed to study PNS symptoms in patients with CSF GFAP-Abs. We retrospectively included all patients tested positive for GFAP-Abs in the CSF by immunohistochemistry and confirmed by cell-based assay expressing human GFAPα since 2017, from two French reference centers. In a cohort of 103 CSF GFAP-Abs patients, 25 (24%) presented with PNS involvement. Among them, the median age at onset was 48years and 14/25 (56%) were female. Abnormal electroneuromyography was observed in 11/25 patients (44%), including eight isolated radiculopathies, one radiculopathy associated with polyneuropathy, one radiculopathy associated with sensory neuronopathy, and one demyelinating polyradiculoneuropathy. Cranial nerve involvement was observed in 18/25 patients (72%). All patients except one had an associated CNS involvement. The first manifestation of the disease concerned the PNS in three patients. First-line immunotherapy was administered to 18/24 patients (75%). The last follow-up modified Rankin Scale was ≤ 2 in 19/23 patients (83%). Patients with PNS involvement had significantly more bladder dysfunction than patients with isolated CNS involvement (68 vs 40.3%, p = 0.031). PNS involvement in GFAP-Abs autoimmunity is heterogeneous but not rare and is mostly represented by acute or subacute cranial nerve injury and/or lower limb radiculopathy. Rarely, PNS involvement can be the first manifestation revealing the disease.

A comparative analysis of demographic, clinical and imaging features of myelin oligodendrocyte glycoprotein antibody positive, aquaporin 4 antibody positive, and double seronegative demyelinating disorders - An Indian tertiary care center prospective study.

The aim of the study was to study the demographical, clinical, radiological features, and outcome of anti-myelin oligodendrocyte glycoprotein (MOG) antibody spectrum disorder and compare these features with patients negative for anti-MOG antibody. MOG antibody-associated disease (MOGAD) and aquaporin-4 (AQP4) antibody-related diseases are immunologically distinct pathologies. Our aim was to compare the clinical and radiological features of MOG antibody-related diseases with AQP4 antibody-related diseases and seronegative demyelinating diseases (Non-multiple sclerosis). This was a prospective and cohort study conducted at an apex tertiary care institute in the northern part of India from Jan 2019 to May 2021. We compared clinical, laboratory, and radiological findings of patients with MOGAD, AQP4 antibody-related diseases, and seronegative demyelinating disease. There were a total of 103 patients - 41 patients of MOGAD, 37 patients of AQP4 antibody-related diseases and 25 seronegative demyelinating disease. Bilateral optic neuritis was the most frequent phenotype in patients with MOGAD (18/41) whereas myelitis was the most common phenotype in the AQP4 (30/37) and seronegative groups (13/25). Cortical, juxtacortical lesions, anterior segment optic neuritis, optic sheath enhancement, and conus involvement in myelitis were radiological findings that separated MOGAD from AQP4 related diseases. Nadir Expanded Disability Status Scale (EDSS) and visual acuity were similar across the groups. Last follow-up EDSS was significantly better in the MOG antibody group as compared to AQP4 antibody group (1 [0-8] vs. 3.5 [0-8]; P = 0.03). Encephalitis, myelitis, and seizures were more common in the younger population (<18 vs. >18 years) in MOGAD (9 vs. 2, P = 0.001; 9 vs. 7, P = 0.03; 6 vs. 0, P = 0.001). We identified several clinical and radiological features that can help physicians to distinguish MOGAD from AQP4-immunoglobulin G+neuromyelitis optica spectrum disorder. Differentiation is vital as treatment response might vary among both groups.

Increased number of T cells and exacerbated inflammatory pathophysiology in a human IgG4 knock-in MRL/lpr mouse model.

Immunoglobulin (Ig) G4 is an IgG subclass that can exhibit inhibitory functions under certain conditions because of its capacity to carry out Fab-arm exchange, inability to form immune complexes, and lack of antibody-dependent and complement-dependent cytotoxicity. Although several diseases have been associated with IgG4, its role in the disease pathogeneses remains unclear. Since mice do not express an IgG subclass that is identical to the human IgG4 (hIgG4), we generated hIGHG4 knock-in (KI) mice and analyzed their phenotypes. To preserve the rearrangement of the variable, diversity, and joining regions in the IGH gene, we transfected a constant region of the hIGHG4 gene into C57BL/6NCrSlc mice by using a gene targeting method. Although the mRNA expression of hIGHG4 was detected in the murine spleen, the serum level of the hIgG4 protein was low in C57BL/6-IgG4KI mice. To enhance the production of IgG4, we established an MRL/lpr-IgG4KI mice model by backcrossing. These mice showed a high IgG4 concentration in the sera and increased populations of IgG4-positive plasma cells and CD3+B220+CD138+ T cells in the spleen. Moreover, these mice showed aggravated inflammation in organs, such as the salivary glands and stomach. The MRL/lpr-IgG4KI mouse model established in the present study might be useful for studying IgG4-related disease, IgG4-type antibody-related diseases, and allergic diseases.

Chapter 14 - Motor symptoms in nonparaneoplastic CNS disorders associated with neural antibodies

Motor symptoms are common, and sometimes predominant, in almost all nonparaneoplastic CNS disorders associated with neural antibodies. These CNS disorders can be classified into five groups: (1) Autoimmune encephalitis with antibodies against synaptic receptors, (2) cerebellar ataxias associated with neuronal antibodies that mostly target intracellular antigens. (3) Stiff-person syndrome and progressive encephalomyelitis with rigidity and myoclonus which have antibodies against glutamic acid decarboxylase and glycine receptor, respectively. Both diseases have in common the presence of predominant muscle stiffness and rigidity. (4) Three diseases associated with glial antibodies. Two present motor symptoms mainly due to the involvement of the spinal cord: neuromyelitis optica spectrum disorders with aquaporin-4 antibodies and myelin oligodendrocyte glycoprotein antibody-associated disease. The third disorder is the meningoencephalitis associated with glial fibrillar acidic protein antibodies which frequently also presents a myelopathy. (5) Two antibody-related diseases which are characterized by prominent sleep dysfunction: anti-IgLON5 disease, a disorder that frequently presents a variety of movement disorders, and Morvan syndrome associated with contactin-associated protein-like 2 antibodies and clinical manifestations of peripheral nerve hyperexcitability. In this chapter, we describe the main clinical features of these five groups with particular emphasis on the presence, frequency, and types of motor symptoms.

A Randomized, Placebo-Controlled, Phase 1 Study in Healthy Adult Volunteers of the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of ALPN303, a Potent Dual BAFF/APRIL Antagonist for the Treatment of Autoimmune Cytopenias

Background B cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) are tumor necrosis factor superfamily (TNFSF) members that bind transmembrane activator and calcium-modulating cyclophilin ligand interactor (TACI), B-cell maturation antigen, and/or BAFF receptor (BAFF-R) on B cells and together support B-cell development, survival, and differentiation into antibody-secreting cells (ASC). In preclinical studies, co-neutralization of BAFF and APRIL can directly suppress ASC and reduce circulating immunoglobulins. Autoimmune hemolytic anemia (AIHA) and immune thrombocytopenic purpura (ITP) are diseases characterized by autoantibodies directed against red blood cells and platelets, respectively. Significantly higher levels of both BAFF and APRIL have been observed in the serum of patients with AIHA and ITP compared to healthy subjects, and polymorphisms in BAFF and TACI have been associated with ITP [Abdel-Hamid, et al., Am J Med, 2011; Emmerich, et al., Br J Haematol, 2007; Peng, et al., J Thromb Haemost, 2017; Yu, et al., Blood Adv, 2021]. Currently, there are no B cell targeting agents approved to treat AIHA or ITP. Rituximab, an anti-CD20 therapeutic which depletes CD20+ B cells, and thereby only indirectly reduces autoantibody production, has demonstrated some efficacy in both ITP [Neunert, et al., Blood, 2019] and AIHA [Jäger, et al., Blood Rev, 2019], though it is not approved for use in either indication. Belimumab, an anti-BAFF neutralizing antibody (Ab), has demonstrated encouraging efficacy in the treatment of ITP associated with systemic lupus erythematosus (SLE) [De Marchi, et al., Clin Exp Rheumatol, 2017] and also in combination with rituximab in patients with ITP [Mahévas, et al., Haematologica, 2021], but only had a modest impact on hematological manifestations in SLE patients [Manzi, et al., Ann Rheum Dis, 2012]. To address the shortcomings of existing B-cell-targeting agents, we have developed ALPN-303, an Fc fusion of an engineered TACI variant TNFRSF domain, which substantially improves upon the ligand affinity liabilities of wild type (WT) TACI, resulting in highly potent dual BAFF/APRIL inhibition superior to WT TACI-Fc, or to BAFF- or APRIL-specific monoclonal Abs. In preclinical studies, ALPN-303 demonstrates enhanced pharmacokinetic (PK) and immunomodulatory properties vs. WT TACI-Fc, which may translate to lower and/or less frequent doses in humans. ALPN-303 also suppresses autoantibodies and nephritis in mouse models of lupus. Taken together, these observations suggest that a potent dual BAFF/APRIL antagonist such as ALPN-303, by lowering pathogenic autoantibody levels, may be particularly beneficial in the treatment of antibody-related hematologic diseases, such as autoimmune cytopenias. Methods In this first-in-human study (NCT05034484), healthy adult volunteers have been enrolled in single ascending dose cohorts of intravenously (IV) or subcutaneously (SC) administered ALPN-303. For each IV cohort, the first 2 sentinel subjects are randomized 1:1 to receive ALPN-303 or placebo, followed by the remaining 4 subjects randomized 3:1 to receive ALPN-303 or placebo. SC cohorts are randomized 4:2 to receive a single SC dose of ALPN-303 or placebo. All subjects are followed to assess safety, PK, and pharmacodynamic (PD) effects including impacts on circulating immunoglobulins (Ig), and peripheral B-cell populations. Results ALPN-303 has been well tolerated in all cohorts evaluated to date and exhibits dose-dependent PK and expected PD effects, including dose-dependent reductions in circulating CD38+ (CD19+CD27+IgD-) ASC (Figure 1) and in serum Ig (Figure 2). To date, there have been no serious adverse events, and no events of cytokine release syndrome. Dose escalation will be complete by the time of the meeting; the presentation will include all available safety, PK, and PD data. Conclusions In this phase 1 study, ALPN-303 demonstrates acceptable preliminary safety and tolerability and exhibits dose-dependent PK and expected PD effects on circulating Ig and B-cell populations. These findings support future clinical development of ALPN-303 in patients with antibody-related diseases, including autoimmune cytopenias. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Meningitis? (Anti-myelin oligodendrocyte glycoprotein immunoglobulin G antibodyrelated disease) A clinical analysis

Objective: By analyzing meningitis? (Anti-myelin oligodendrocyte glycoprotein immunoglobulin G antibody-related diseases) clinical diagnosis and treatment methods to improve clinicians’ understanding of autoimmune encephalitis. Methods: Collect 1 case of meningitis? (Anti-myelin oligodendrocyte glycoprotein immunoglobulin G antibody-related disease) patient’s clinical data, combined with literature review, to analyze the diagnosis and treatment methods of this case. Results: The patient, male, 26 years old, was admitted to the hospital mainly because of “headache for 12 days and convulsions once”. After imaging examination, hematology examination, body fluid examination, and repeated confirmation of the clinical treatment plan through remote consultation, hormones, immunosuppressants, immunoglobulins, anti-inflammatory and anti-viral treatments were given. He was discharged from the hospital and re-examined 2 months later. His condition became stable and his indicators improved. Conclusion: For patients with autoimmune encephalitis, in addition to actively doing antibody detection and adjuvant therapy, it is necessary to adhere to the treatment plan mainly focusing on the treatment of autoimmune encephalitis, and do not focus too much on the relevant antibody indicators, so as to avoid deviations in the formulation of treatment plans, resulting in The condition fluctuates, and the patient’s condition persists.

Optic neuritis in Asian type opticospinal multiple sclerosis (OSMS-ON) in a non-Asian population: A functional-structural paradox

BackgroundBiomarkers have improved the classification of autoimmune inflammatory disorders, including optic neuritis (ON) as a frequent presentation of multiple sclerosis, neuromyelitis spectrum disorders, MOG antibody-related disease (MOGAD), and opticospinal multiple sclerosis (OSMS). The phenotype of OSMS in non-Asian populations is less well known. ObjectiveWe investigated the clinical features and prognosis of OSMS–ON in a Brazilian cohort. MethodsThis was a single-center cohort study of patients from Rio de Janeiro (Brazil) with OSMS. All individuals were MOG- and AQP4-seronegative, clinically diagnosed with ON, and had magnetic resonance imaging-confirmed transverse myelitis (TM). Subjects and healthy controls (HCs) were assessed for visual acuity (logMAR VA), automated perimetry mean deviation (MD), intraocular pressure, and spectral-domain optical coherence tomography (OCT), followed by automated retinal layer segmentation of the peripapillary retinal nerve fiber layer (pRNFL) and macular ganglion cell and inner plexiform layer (mGCIPL). Receiver operator characteristic curves were plotted and the area under the curve (AUC) was calculated for group comparisons of retinal asymmetry of the pRNFL and mGCIPL. ResultsThe 30 patients with OSMS were predominantly female and white. The mean age was 48 years (range 20–70 years). Unilateral ON was the index event in 83.3% of patients. Over the average 18-year follow-up period, there were 89 relapses of ON. In individuals with OSMS, the average VA was 0.07±0.14 in the right eye (RE) and 0.13±0.30 in the left eye (LE). The MD was −5.37±5.88 dB and −5.23±3.34 dB for the RE and LE, respectively. There was a significant cumulative loss of VA (p = 0.0003) and MD (p = 0.0001) with a higher number of recurrent episodes. Atrophy of the pRNFL thickness was significant in OSMS (RE, 78.62 ± 16.01 µm; LE, 79.86 ± 13.79 µm) relative to the HC group (RE, 98.87 ± 10.68 µm; LE, 97.87 ± 10.85 µm, p = 0.0001). Likewise, there was significant mGCIPL atrophy in patients with OSMS (RE, 74.96 ± 14.46 µm; LE, 73.88 ± 13.79 µm) relative to the HC group (RE, 90.50 ± 6.74 µm; LE, 90.41± 6.89 µm; p = 0.0001). Retinal asymmetry, inter-eye percentage, and absolute differences accurately separated patients with unilateral ON from HCs (AUC=0.89 and AUC=0.85, respectively). ConclusionA structural-functional paradox was found in OSMS with a high diagnostic value for a novel metric based on retinal asymmetry. The functional visual outcome are excellent despite significant structural damage to the inner retinal layers in patients with a high ON relapse rate and long-term bilateral sequential involvement.

FTY720 Exacerbates Blood-Brain Barrier Dysfunction Induced by IgG Derived from Patients with NMO and MOG Disease.

Neuromyelitis optica (NMO) and myelin oligodendrocyte glycoprotein (MOG) antibody-related disease (MOG disease) are inflammatory demyelinating diseases of the central nervous system (CNS). The disruption of the blood-brain barrier (BBB) is considered a key step in the pathogenesis of NMO and MOG disease. Although a previous report indicated that circulating immunoglobulin G (IgG) from NMO patients disrupts the BBB, the effect of IgG from patients with MOG disease has not been elucidated. In addition, it has been reported that some disease-modifying drugs for multiple sclerosis are harmful to NMO by an unknown mechanism. This study aimed to examine the effects of IgG from patients with NMO or MOG disease on BBB integrity. We also examined the effects of disease-modifying drugs (fingolimod [FTY720] and dimethyl fumarate [DMF]) on IgG-treated brain capillary endothelial cells. We used in vitro BBB models constructed with rat brain capillary endothelial cells (RBECs) to examine the effects on BBB function. The integrity of the RBECs was assessed by measuring transendothelial resistance (TEER) and cell viability. NMO or MOG-IgG treatment decreased TEER and cell viability in the endothelial monolayer model. Although FTY720 and DMF did not affect barrier function or cell viability under normal conditions, disease IgG-induced barrier dysfunctions were worsened by the presence of FTY720. These data indicate that circulating IgG in patients with NMO or MOG disease worsens BBB function. Furthermore, in patients with NMO or MOG disease treated with FTY720, changes in the integrity of the BBB were found to exacerbate the disease.

After discharges following compound muscle action potential in CASPR2 antibody-related disease

A 75-year-old man had a 3-month history of shooting and burning pain in all four limbs, with painless muscle twitches, fatigue and moderate weight loss. During this time, he had...

Efficacy for the Annual Relapse Rate after the Immunosuppressive Therapy in Patients Associated with Anti-AQP4 or Anti-MOG Antibody-Positive Optic Neuritis.

Purpose Although oral prednisolone is the first-line treatment for preventing recurrent optic neuritis (ON) after the completion of acute-phase treatment, especially anti-aquaporin 4 (AQP4) antibody-positive ON, and anti-myelin oligodendrocyte glycoprotein (MOG) antibody-positive ON, some patients experience relapses. Immunosuppressants could be effective in reducing the recurrence rate for neuromyelitis optica spectrum disorder and MOG antibody-related diseases, but there have been few studies addressing this issue focusing on the changes in ophthalmic parameters. The objective of the study was to analyze the impact of off-label uses of immunosuppressants to reduce recurrent ON. Design Retrospective observational study, clinical case series. Methods We reviewed the medical charts of 11 cases (22 eyes) who underwent immunosuppressive therapy in Kobe University Hospital and compared the annualized relapse rate (ARR) before and after immunosuppressive therapy. We also evaluated the dosage of prednisolone, complications of immunosuppressants, and other visual functional ophthalmologic parameters. Results Eleven cases in total had AQP4 antibody (9 cases) and/or MOG antibody (3 cases). One case was double positive for these antibodies. Nine patients received azathioprine and two received mycophenolate mofetil as an initial immunosuppressive therapy. The median duration of immunosuppressant treatment was 2.8 years. The median ON ARR before immunosuppressive therapy was 0.33, and this decreased significantly to 0 after the therapy (p = 0.02). The dose of prednisolone was reduced from 17.8 ± 7.1 mg/day before to 5.8 ± 2.2 mg/day after immunosuppressive therapy (p < 0.01). Although two patients presented with mild elevation of liver enzymes and nausea, all patients were able to continue taking the immunosuppressants. Conclusions Immunosuppressants can potentially decrease relapses and steroid dosage in patients with anti-AQP4 or MOG antibody-positive ON without severe adverse events and the exacerbation of visual acuities.

Is Asian type MS an MS phenotype, an NMO spectrum disorder, or a MOG-IgG related disease?

BackgroundA specific particularity of neurological diseases in Asia is the relative commonality of neuromyelitis optica (NMO) and Asian type MS (OSMS). Both conditions also occur in South American patients. The Brazilian population differs from the European and the Asian populations due to the mixture of ancestralities between European colonizers and African slaves. To better know the clinical characteristics of Brazilian patients with Asian type MS this study aimed to analyze the clinical, radiological and serological data that would help to distinguish between OSMS and NMO and clarify, in a Non-Asian population, if OSMS is an MS phenotype, an NMO spectrum disorder by 2015 classification, or a complement activating antibody to myelin oligodendrocyte glycoprotein (MOG-IgG) antibody-related disease. MethodsWe selected cases retrospectively with NMO and OSMS in the medical registry of patients with idiopathic inflammatory demyelinating diseases under follow-up since 1997 in Federal Hospital da Lagoa, the principal reference center for MS treatment in Rio de Janeiro, Brazil. OSMS has selective involvement of the optic nerve and spinal cord with no cerebral or cerebellar symptoms associated with small spinal cord lesions and negativity for the aquaporin-4 antibody (AQP4-IgG). NMO full-filled the revised criteria (2006) associated with longitudinally extensive transverse myelitis (LETM). We recorded the following data: ethnicity/skin color, neurologic impairment “at nadir” and “at recovery” of the index events (optic neuritis and transverse myelitis), long term disability, mortality, health quality of life scores by the SF-36 questionnaire, CSF IgG oligoclonal bands and serological AQP4-IgG and MOG-IgG antibodies tested by Cell-based assay. The last brain MRIs were classified as either satisfying or not satisfying MAGNIMS radiologic criteria for MS or typical or not typical for NMOSD. The new classification of NMO spectrum disorders (2015) was applied. ResultsForty-one OSMS and 122 NMO cases were analyzed. OSMS affected mainly young white women, causing unilateral optic neuritis and partial myelitis with excellent recovery. After a mean disease duration of 20 years, 90% of the patients had free ambulation, and 70% had a mild disability or no disability. Only 7.2% presented a secondary progressive course, and no deaths occurred. All cases had negativity to AQP4-IgG and MOG-IgG biomarkers. 95% had resonance criteria for MS. OSMS differed from NMO by ethnicity, morbidity, and mortality: most were African descendants, with severe motor and visual dysfunction, and one third died. Only NMO cases full-filled the new NMOSD classification (52 AQP4-IgG positive, 29 AQP4-IgG negative, and 41 AQP4-IgG unknown). ConclusionIn Brazilian patients, OSMS and NMO are different immune-mediated diseases. OSMS is a milder MS phenotype.

Movement disorders with neuronal antibodies: syndromic approach, genetic parallels and pathophysiology.

Movement disorders are a prominent and common feature in many autoantibody-associated neurological diseases, a group of potentially treatable conditions that can mimic infectious, metabolic or neurodegenerative disease. Certain movement disorders are likely to associate with certain autoantibodies; for example, the characteristic dyskinesias, chorea and dystonia associated with NMDAR antibodies, stiff person spectrum disorders with GAD, glycine receptor, amphiphysin or DPPX antibodies, specific paroxysmal dystonias with LGI1 antibodies, and cerebellar ataxia with various anti-neuronal antibodies. There are also less-recognized movement disorder presentations of antibody-related disease, and a considerable overlap between the clinical phenotypes and the associated antibody spectra. In this review, we first describe the antibodies associated with each syndrome, highlight distinctive clinical or radiological 'red flags', and suggest a syndromic approach based on the predominant movement disorder presentation, age, and associated features. We then examine the underlying immunopathophysiology, which may guide treatment decisions in these neuroimmunological disorders, and highlight the exceptional interface between neuronal antibodies and neurodegeneration, such as the tauopathy associated with IgLON5 antibodies. Moreover, we elaborate the emerging pathophysiological parallels between genetic movement disorders and immunological conditions, with proteins being either affected by mutations or targeted by autoantibodies. Hereditary hyperekplexia, for example, is caused by mutations of the alpha subunit of the glycine receptor leading to an infantile-onset disorder with exaggerated startle and stiffness, whereas antibodies targeting glycine receptors can induce acquired hyperekplexia. The spectrum of such immunological and genetic analogies also includes cerebellar ataxias and some encephalopathies. Lastly, we discuss how these pathophysiological considerations could reflect on possible future directions regarding antigen-specific immunotherapies or targeting the pathophysiological cascades downstream of the antibody effects.

Insights into the pathogenesis of multiple sclerosis: genetics and environment

It has been a great honor to host the second MS Summer College in Sapporo. For the past 13 years, clinicians and researchers involved in multiple sclerosis (MS) research have gathered to present their most recent findings and to engage in enthusiastic and informative discussions. Last year, the meeting was reconceived as the first MS Summer College, organized by Professor Kira, and building on the success of that first meeting, it is my great pleasure to welcome everyone to the second MS Summer College. I have confidence that we will continue to advance MS research while deepening our friendship at the same time. The theme of this second MS Summer College was “Insights into the pathogeneses of MS: genetics and environment.” The development of MS is influenced by interactions between multiple genetic and environmental factors. Historically, epidemiological studies have provided clues for the triggers of MS. These studies have identified latitude, or vitamin D as an important risk factor for MS. In addition, the observed link between infectious agents such as Epstein–Barr (EB) virus and MS has led to the “hygiene hypothesis” of MS development, which is further supported by recent advances in the field of mucosal immunology. At this meeting, Professor Goodin gave us an overview of the epidemiology of MS. In the following sessions, Professor Ohno and Dr. Okuno presented their current research on immune regulation by gut microflora, and Professor Fujiwara described recent progress made in the field of autoimmunity triggered by EB virus. In addition to epidemiological and immunological approaches, genetic studies using advanced technologies have identified several human leukocyte antigen (HLA) and non-HLA susceptibility loci involved in MS development. Continued advances in MS genetics lead to the elucidation of MS etiology and further aided in drug discovery and development. Professor Matsushita gave a comprehensive review of recent advances and perspectives in genetic studies on MS. As the effects of individual genes or even combinations of genes on MS development are relatively minor, they explain, at most, only half of the genetic risks for developing MS. Therefore, the limitations of these genetic studies based on “common disease–common variant hypothesis” have been pointed out. In this context, epigenetic mechanisms have been suggested as underlying MS pathogenesis and may partly explain the “missing heritability” of this complex disease. To discuss this in detail, Professor Iwamoto, following an overview of epigenetic studies on MS presented by Dr. Miyazaki, described the recent progress made in the epigenetics of psychiatric disorders, which is expected to provide insights into future research in MS epigenetics. We were also pleased to host Professor Nakashima, who gave a special clinical lecture on the recently identified anti-myelin oligodendrocyte glycoprotein (MOG) antibody-related disease, which has recently been identified among anti-AQP4 antibody-negative neuromyelitis optica and other demyelinating disorders. All these exciting and informative lectures were held in Sapporo, a young and vibrant city surrounded by beautiful nature and with abundant fresh food. I am firmly convinced that this issue of Clinical and Experimental Neuroimmunology (Supplemental Vol. 6) will provide you with the most recent progress in MS research and convey the stimulating atmosphere of the second MS Summer College. The author has no financial interests in the publication of the contents of this article or has no relationships with any company with such financial interests.

56.: Phenotypic variation in Miller Fisher syndrome

This study aims to describe the diverse clinical presentations associated with anti-GQ1b antibody positivity. We report four patients with Miller Fisher Syndrome (MFS) admitted over a period of 3 months to a single tertiary hospital in Sydney, NSW, Australia. Only one patient presented with the classical clinical triad of ataxia, areflexia and ophthalmoplegia. The three other patients presented with a range of signs including blepharoptosis, pseudo-internuclear opthalmoplegia and pseudo-proptosis. Two patients had positive repetitive nerve stimulation and were mistaken for ocular myasthenia gravis. All patients had strongly positive immunoglobulin G anti-GQ1b antibodies detected. While the diversity of clinical presentations delayed formal diagnosis, treatment with intravenous immunoglobulin therapy prompted a complete recovery in all patients. Our patients highlight the spectrum of clinical features associated with GQ1b antibodies. While the classic triad of acute ophthalmoplegia, ataxia, and areflexia is a highly recognisable clinical entity, anti-GQ1b antibody-related disease should also be suspected in patients with limited or atypical forms of Miller Fisher syndrome.

Anti-glutamate receptor ɛ2 antibodies in psychiatric patients with anti-thyroid autoantibodies – A prevalence study in Japan

Patients with anti-thyroid antibodies (ATAs) present various kinds of psychiatric conditions. When these psychiatric patients with ATAs (PPATs) show responsiveness to immunotherapy, they are frequently diagnosed with a diffuse progressive type of Hashimoto's encephalopathy (HE). Anti-glutamate receptor ɛ2 subunit (GluRɛ2) antibodies have previously been reported in HE patients. However, it is unclear whether there is any relationship between PPATs, including HE patients, and anti-GluRɛ2 antibodies. We investigated anti-GluRɛ2 antibodies in the serum and cerebrospinal fluid (CSF) of 15 PPATs, and we compared the results with those of 11 patients with neuropsychiatric systemic lupus erythematosus (NPSLE), an anti-glutamate receptor antibody-related disease. We then compared the neuropsychiatric symptoms between the PPATs with and without anti-GluRɛ2 antibodies. The prevalence of anti-GluRɛ2 antibodies was significantly higher in the CSF than in the serum of PPATs (41.7% versus 6.7%; p=0.040). The prevalence of anti-GluRɛ2 antibodies was slightly higher in the CSF of PPATs than NPSLE patients. PPAT-GluR(+)s showed a significantly higher prevalence of emotional instability (100% versus 33.3%; p=0.03) and also showed a significantly lower prevalence of delusions (0% versus 100%; p=0.001) and hallucinations (17% versus 83%; p=0.038) than PPAT-GluR(−)s. Our results suggest that anti-GluRɛ2 antibodies may be associated with the neuropsychiatric manifestation of PPATs.

Acute tubulointerstitial nephritis associated with autoimmune-related pancreatitis

Various etiologic factors have been identified in tubulointerstitial nephritis (TIN), including allergic drug reaction, infection, and immune-mediated disease. Immune-mediated TIN without significant glomerular involvement has been reported to occur as a renal complication secondary to Sjögren's syndrome, lupus nephritis, and antitubular basement membrane antibody-related disease. We present a first case of acute TIN associated with autoimmune-related pancreatitis (AIP). A 64-year-old man was referred to our division from a surgeon for the close examination of renal dysfunction. The pancreatic and biliary imaging showed segmental narrowing of the pancreatic duct with localized swelling of the pancreatic head, suggesting the carcinoma of the pancreatic head at that time. However, the laboratory findings also showed renal dysfunction with high level of serum immunoglobulin G and hypocomplemetemia. Renal biopsy was performed to investigate the etiology of the renal dysfunction. The renal biopsy specimen showed acute TIN. The patient had no drug history, which may cause TIN. Oral corticosteroid therapy improved the renal function as well as histological damage, the pancreatic imaging study, and the laboratory tests of pancreatic and hepatobiliary enzyme. Although the pancreatic biopsy has not performed in our patient, his clinical course confirmed us that AIP was the final diagnosis for his pancreatic lesion. Despite further examination, there was no evidence of other autoimmune-related diseases such as Sjögren's syndrome. To our knowledge, this is the first report of acute TIN associated with AIP. We suggest that AIP may be an etiologic factor in some cases of TIN.