Tomomi Yonekawa

Characteristic Cerebrospinal Fluid Cytokine/Chemokine Profiles in Neuromyelitis Optica, Relapsing Remitting or Primary Progressive Multiple Sclerosis

Background Differences in cytokine/chemokine profiles among patients with neuromyelitis optica (NMO), relapsing remitting multiple sclerosis (RRMS), and primary progressive MS (PPMS), and the relationships of these profiles with clinical and neuroimaging features are unclear. A greater understanding of these profiles may help in differential diagnosis. Methods/Principal Findings We measured 27 cytokines/chemokines and growth factors in CSF collected from 20 patients with NMO, 26 with RRMS, nine with PPMS, and 18 with other non-inflammatory neurological diseases (OND) by multiplexed fluorescent bead-based immunoassay. Interleukin (IL)-17A, IL-6, CXCL8 and CXCL10 levels were significantly higher in NMO patients than in OND and RRMS patients at relapse, while granulocyte-colony stimulating factor (G-CSF) and CCL4 levels were significantly higher in NMO patients than in OND patients. In NMO patients, IL-6 and CXCL8 levels were positively correlated with disability and CSF protein concentration while IL-6, CXCL8, G-CSF, granulocyte-macrophage colony-stimulating factor (GM-CSF) and IFN-γ were positively correlated with CSF neutrophil counts at the time of sample collection. In RRMS patients, IL-6 levels were significantly higher than in OND patients at the relapse phase while CSF cell counts were negatively correlated with the levels of CCL2. Correlation coefficients of cytokines/chemokines in the relapse phase were significantly different in three combinations, IL-6 and GM-CSF, G-CSF and GM-CSF, and GM-CSF and IFN-γ, between RRMS and NMO/NMOSD patients. In PPMS patients, CCL4 and CXCL10 levels were significantly higher than in OND patients. Conclusions Our findings suggest distinct cytokine/chemokine alterations in CSF exist among NMO, RRMS and PPMS. In NMO, over-expression of a cluster of Th17- and Th1-related proinflammatory cytokines/chemokines is characteristic, while in PPMS, increased CCL4 and CXCL10 levels may reflect on-going low grade T cell and macrophage/microglia inflammation in the central nervous system. In RRMS, only a mild elevation of proinflammatory cytokines/chemokines was detectable at relapse.

Anti-neurofascin antibody in patients with combined central and peripheral demyelination

Objectives: We aimed to identify the target antigens for combined central and peripheral demyelination (CCPD). Methods: We screened target antigens by immunohistochemistry and immunoblotting using peripheral nerve tissues to identify target antigens recognized by serum antibodies from selected CCPD and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) cases. We then measured the level of antibody to the relevant antigen in 7 patients with CCPD, 16 patients with CIDP, 20 patients with multiple sclerosis, 20 patients with Guillain-Barré syndrome, 21 patients with other neuropathies, and 23 healthy controls (HC) by ELISA and cell-based assays using HEK293 cells. Results: At the initial screening, sera from 2 patients with CCPD showed cross-like binding to sciatic nerve sections at fixed intervals, with nearly perfect colocalization with neurofascin immunostaining at the node and paranode. ELISA with recombinant neurofascin revealed significantly higher mean optical density values in the CCPD group than in other disease groups and HC. Anti-neurofascin antibody positivity rates were 86% in patients with CCPD, 10% in patients with multiple sclerosis, 25% in patients with CIDP, 15% in patients with Guillain-Barré syndrome, and 0% in patients with other neuropathies and HC. The cell-based assay detected serum anti-neurofascin antibody in 5 of 7 patients with CCPD; all others were negative. CSF samples examined from 2 patients with CCPD were both positive. In anti-neurofascin antibody–positive CCPD patients, including those with a limited response to corticosteroids, IV immunoglobulin or plasma exchange alleviated the symptoms. Conclusion: Anti-neurofascin antibody is frequently present in patients with CCPD. Recognition of this antibody may be important, because patients with CCPD who are antibody positive respond well to IV immunoglobulin or plasma exchange.

Distinct genetic and infectious profiles in Japanese neuromyelitis optica patients according to anti-aquaporin 4 antibody status

Objective To clarify whether genetic and common infectious backgrounds are distinct, according to anti-aquaporin 4 (AQP4) antibody status in Japanese patients with neuromyelitis optica (NMO). Methods We analysed human leucocyte antigen (HLA)-DRB1 and HLA-DPB1 alleles, and IgG antibodies against Helicobacter pylori, Chlamydia pneumoniae, varicella zoster virus and Epstein–Barr virus nuclear antigen (EBNA) in 116 patients with NMO, including 39 patients with neuromyelitis optica spectrum disorder (NMOSD), 145 multiple sclerosis (MS) patients and 367 unrelated healthy controls. 77 NMO/NMOSD patients were seropositive for AQP4 antibody while 39 were seronegative. Results Compared with healthy controls, NMO/NMOSD patients showed a significantly lower frequency of DRB1*0901 and significantly higher frequencies of DRB1*1602 and DPB1*0501, which conferred susceptibility to anti-AQP4 antibody positive NMO/NMOSD, but not antibody negative NMO/NMOSD. DRB1*0901 was a common protective allele, irrespective of the presence or absence of anti-AQP4 antibody. Anti-H pylori and anti-C pneumoniae antibodies were more commonly detected in anti-AQP4 antibody positive NMO/NMOSD patients than healthy controls. Antibody negative NMO/NMOSD patients did not differ from healthy controls regarding the presence of these antibodies. The presence or absence of antibodies against varicella zoster virus and EBNA did not vary among the groups. The frequencies of antibodies against these four pathogens were not significantly different between MS patients and healthy controls. Conclusions Our results suggest that HLA-DRB1*1602 and DPB1*0501 alleles and H pylori and Chlamydia pneumonia infection are risk factors only for anti-AQP4 antibody positive NMO/NMOSD but not for anti-AQP4 antibody negative NMO/NMOSD.

Genetic and Infectious Profiles of Japanese Multiple Sclerosis Patients

Background Nationwide surveys conducted in Japan over the past thirty years have revealed a four-fold increase in the estimated number of multiple sclerosis (MS) patients, a decrease in the age at onset, and successive increases in patients with conventional MS, which shows an involvement of multiple sites in the central nervous system, including the cerebrum and cerebellum. We aimed to clarify whether genetic and infectious backgrounds correlate to distinct disease phenotypes of MS in Japanese patients. Methodology/Principal Findings We analyzed HLA-DRB1 and -DPB1 alleles, and IgG antibodies specific for Helicobacter pylori, Chlamydia pneumoniae, varicella zoster virus, and Epstein-Barr virus nuclear antigen (EBNA) in 145 MS patients and 367 healthy controls (HCs). Frequencies of DRB1*0405 and DPB1*0301 were significantly higher, and DRB1*0901 and DPB1*0401 significantly lower, in MS patients as compared with HCs. MS patients with DRB1*0405 had a significantly earlier age of onset and lower Progression Index than patients without this allele. The proportion and absolute number of patients with DRB1*0405 successively increased with advancing year of birth. In MS patients without DRB1*0405, the frequency of the DRB1*1501 allele was significantly higher, while the DRB1*0901 allele was significantly lower, compared with HCs. Furthermore, DRB1*0405-negative MS patients were significantly more likely to be positive for EBNA antibodies compared with HCs. Conclusions Our study suggests that MS patients harboring DRB1*0405, a genetic risk factor for MS in the Japanese population, have a younger age at onset and a relatively benign disease course, while DRB1*0405-negative MS patients have features similar to Western-type MS in terms of association with Epstein-Barr virus infection and DRB1*1501. The recent increase of MS in young Japanese people may be caused, in part, by an increase in DRB1*0405-positive MS patients.

A nationwide survey of hypertrophic pachymeningitis in Japan

Objectives To clarify the prevalence, frequent causes and distinct features of hypertrophic pachymeningitis (HP) according to background conditions in a nationwide survey in Japan. Methods The study began with a preliminary survey to determine the approximate number of HP patients diagnosed from 1 January 2005 to 31 December 2009, and was followed by a questionnaire survey for clinical and laboratory findings. HP was defined as a condition with thickening of the cranial or spinal dura mater with inflammation, evidenced by MRI or histology. Results Crude HP prevalence was 0.949/100 000 population. The mean age at onset was 58.3±15.8 years. Among 159 cases for whom detailed data were collated, antineutrophil cytoplasmic antibody (ANCA)-related HP was found in 54 cases (34.0%) and IgG4/multifocal fibrosclerosis (MFS)-related HP in 14 cases (8.8%). Seventy cases (44.0%) were classified as ‘idiopathic’ and 21 (13.2%) as ‘others’. ANCA-related HP cases showed a female preponderance, a higher age of onset, and higher frequencies of otological symptoms and elevated systemic inflammatory biomarkers, but lower frequencies of diplopia compared with idiopathic HP. IgG4/MFS-related HP cases showed a marked male predominance; all had cranial HP while none had isolated spinal HP or decreased sensation. Conclusions HP is not extremely rare. ANCA-related HP is the most frequent form, followed by IgG4/MFS-related HP. Both forms have unique features, which may help to differentiate background causes.

Extensive loss of connexins in Baló's disease: Evidence for an auto-antibody-independent astrocytopathy via impaired astrocyte-oligodendrocyte/ myelin interaction

Extensive aquaporin-4 (AQP4) loss without perivascular deposition of either activated complement or immunoglobulins is a characteristic of Baló’s disease. Our aim in this study was to investigate the relationship between astrocytopathy and demyelination in Baló’s disease, focusing on connexins (Cx), which form gap junctions among glial cells and myelin. Autopsied specimens from four cases that provided seven actively demyelinating concentric lesions infiltrated with numerous CD68+ macrophages were immunohistochemically examined for the astrocyte markers glial fibrillary acidic protein (GFAP), AQP4, Cx43, Cx30 and megalencephalic leukoencephalopathy with subcortical cyst 1 (MLC1). Specimens were also stained for oligodendrocyte/myelin markers, namely Cx32, Cx47, myelin-associated glycoprotein (MAG), myelin oligodendrocyte glycoprotein (MOG), oligodendrocyte-specific protein (OSP) and Nogo-A. Serum samples from six patients that had undergone magnetic resonance imaging, confirming a diagnosis of Baló’s disease, were assayed for the presence of anti-Cx43, -Cx32 and -AQP4 antibodies. Despite the presence of numerous GFAP- and MLC1-positive astrocytes, there was a marked decrease in the levels of Cx43, Cx32 and Cx47. At the leading edges, Cx43 and AQP4 were mostly absent despite positive GFAP, MLC1, Cx32, Cx47, MOG, MAG, and OSP immunoreactivity. Of the six Baló’s disease patients, none were positive for anti-Cxs or -AQP4 antibodies. Baló’s disease is characterized by extensive loss of Cxs and AQP4, and a lack of auto-antibodies to Cxs and AQP4. Loss of Cx43 and AQP4 in the presence of other oligodendrocyte/myelin proteins at the leading edges suggests the possibility that auto-antibody-independent astrocytopathy may contribute to disease pathology via the disruption of astrocyte–oligodendrocyte/myelin interactions.

Quantitative assays for anti-aquaporin-4 antibody with subclass analysis in neuromyelitis optica

Background: To clarify the clinical relevance of anti-aquaporin-4 (anti-AQP4) antibody titers and immunoglobulin (IgG) subclass. Methods: Using a bridging enzyme-linked immunosorbent assay (ELISA), a flow cytometric assay (FCMA) and an immunofluorescence assay (IFA) for anti-AQP4 antibodies, sera from 142 patients with multiple sclerosis (MS) as defined by the McDonald criteria (2005), 29 with neuromyelitis optica (NMO) who fulfilled the 1999 criteria, 19 with recurrent and/or longitudinally extensive myelitis (RM/LM), 86 with other non-inflammatory neurological diseases (OND) and 28 healthy controls (HC) were studied. Results: Anti-AQP4 antibody positivity rates by IFA, FCMA, and ELISA were 41.4%, 51.7% and 48.3%, respectively, in NMO (1999) patients, and 0% in the OND and HC groups. Twenty-six MS patients (18.3%) were positive for the antibody; 17 met the 2006 NMO criteria, including positivity for anti-AQP4 antibody, and five had longitudinally extensive myelitis (LM). Among the cases with anti-AQP4 antibody detected by FCMA, IgG1, 2, 3, and 4 anti-AQP4 antibodies were found in 97.8%, 37.0%, 6.5% and 6.5% respectively. There was no association of either antibody positivity or level of anti-AQP4 antibody IgG subclasses with clinical parameters after adjustment of p values for multiple comparisons. Conclusions: FCMA and bridging ELISA are useful for detecting and quantifying anti-AQP4 antibodies.

A nationwide survey of combined central and peripheral demyelination in Japan

Objectives To clarify the clinical features of combined central and peripheral demyelination (CCPD) via a nationwide survey. Methods The following characteristics were used to define CCPD: T2 high-signal intensity lesions in the brain, optic nerves or spinal cord on MRI, or abnormalities on visual-evoked potentials; conduction delay, conduction block, temporal dispersion or F-wave abnormalities suggesting demyelinating neuropathy based on nerve conduction studies; exclusion of secondary demyelination. We conducted a nationwide survey in 2012, sending questionnaires to 1332 adult and paediatric neurology institutions in Japan. Results We collated 40 CCPD cases, including 29 women. Age at onset was 31.7±14.1 years (mean±SD). Sensory disturbance (94.9%), motor weakness (92.5%) and gait disturbance (79.5%) were common. Although cerebrospinal fluid protein levels were increased in 82.5%, oligoclonal IgG bands and elevated IgG indices were detected in 7.4% and 18.5% of cases, respectively. Fifteen of 21 patients (71.4%) had abnormal visual-evoked potentials. Antineurofascin 155 antibodies were positive in 5/11 (45.5%). Corticosteroids, intravenous immunoglobulins and plasmapheresis resulted in an 83.3%, 66.7% and 87.5% improvement, respectively, whereas interferon-β was effective in only 10% of cases. CCPD cases with simultaneous onset of central nervous system (CNS) and peripheral nervous system (PNS) involvement exhibited greater disability, but less recurrence and more frequent extensive cerebral and spinal cord MRI lesions compared to those with temporarily separated onset, whereas optic nerve involvement was more common in the latter. Conclusions CCPD shows different characteristics from classical demyelinating diseases, and distinctive features exist between cases with simultaneous and temporarily separated onset of CNS and PNS involvement.

Interleukin-7 receptor alpha gene polymorphism influences multiple sclerosis risk in Asians

A recent genome-wide survey identified non–human leukocyte antigen ( HLA ) genes that are related to multiple sclerosis (MS). Among these, an association of a single nucleotide polymorphism (SNP), rs6897932, in the interleukin-7 receptor α gene ( IL-7RA ) with MS susceptibility has been widely replicated in Caucasians.1,–,3 The SNP located in the transmembrane domain of IL-7Rα is nonsynonymous and functional: the MS-susceptible CC allele increases levels of the soluble form of IL-7Rα via exon skipping, and decreases the expression of membrane-bound IL-7Rα, thereby causing decreased IL-7/IL-7R signaling.1,–,3 IL-7/IL-7R signaling induces thymic production of FOXP3+ regulatory T cells, which efficiently ameliorate experimental autoimmune encephalomyelitis,4 an animal model of MS. Thus, the rs6897932 polymorphism of the IL-7RA gene may confer MS susceptibility through decreased production of FOXP3+ regulatory T cells due to downregulated IL-7/IL-7R signaling. This polymorphism has never been reported in either MS or neuromyelitis optica (NMO) in Asians. Therefore, in the present cross-sectional study, we investigated the association of the IL-7RA SNP rs6897932 with non-NMO MS and NMO in the Japanese. ### Methods. All patients with NMO fulfilled the 2006 Wingerchuk5 criteria for NMO, while those with NMO spectrum disorders who did not completely meet the criteria were excluded. All non-NMO patients with MS satisfied …

Comparison of clinical, immunological and neuroimaging features between anti-aquaporin-4 antibody-positive and antibody-negative Sjögren’s syndrome patients with central nervous system manifestations

Background and objective: The objective of this study is to clarify clinical, immunological, and neuroimaging features in anti-aquaporin-4 (AQP4) antibody-positive and antibody-negative Sjögren’s syndrome (SS) patients with central nervous system (CNS) involvement. Methods: Medical records and MRI scans were retrospectively analyzed in 22 consecutive SS patients with CNS manifestations. Results: Seven (31.8%) patients were positive for anti-AQP4 antibodies. The frequency of visual impairment was higher in anti-AQP4 antibody-positive patients than in antibody-negative patients (71.4% vs. 0.0%, p = 0.0008). Brain MRI showed that discrete lesions were more commonly found in the cerebrum, brainstem, and optic nerve in anti-AQP4 antibody-positive patients than in antibody-negative patients (p = 0.002, p = 0.006, and p = 0.004, respectively), while spinal cord MRI showed that posterior column lesions in the cervical spinal cord were more frequent in anti-AQP4 antibody-positive patients than in antibody-negative patients (71.4% vs. 14.3%, p = 0.01). SS-A antibody titers were higher in anti-AQP4 antibody-positive patients than in antibody-negative patients (p = 0.012) and were also higher in patients with longitudinally extensive spinal cord lesions (LESCLs) than in those without LESCLs (p = 0.019). Conclusions: In SS, the presence of anti-AQP4 antibodies is associated with involvement of the optic nerve, cerebrum and brainstem, and with cervical posterior column lesions in the spinal cord.