Consistent increase in the prevalence and female ratio of multiple sclerosis over 15 years in northern Japan.

BACKGROUND AND PURPOSE: The prevalence of multiple sclerosis (MS) is considered to be lower in East Asia than in Western countries. An increasing trend has been reported globally for the prevalence of MS. We investigated the changes in the prevalence and clinical characteristics of MS in the Tokachi province of Hokkaido, northern Japan from 2001 to 2016. METHODS: Prevalence was determined on 31 March 2016. Data-processing sheets were collected from all MS-related institutions in Tokachi province. We applied Poser's diagnostic criteria for MS as used in our previous three studies. Cases of neuromyelitis optica spectrum disorders were excluded. RESULTS: In 2016, the crude MS prevalence was 18.6/100 000 (95% confidence interval, 14.3-23.8) in northern Japan. Over the last 15 years, the prevalence of MS in the same area was 8.1, 12.6 and 16.2 in 2001, 2006 and 2011, respectively. The female:male ratio was 3.57, which increased from 2.63 in 2001. The ratios of primary progressive, relapsing-remitting and secondary progressive MS types were 2%, 84% and 14%, respectively. CONCLUSION: Our results demonstrated a consistent increase in MS prevalence among the northern Japanese population, particularly in females, and relatively lower rates of progressive MS in northern Japan than in Western countries.

Structural basis for the altered drug sensitivities of non-small cell lung cancer-associated mutants of human epidermal growth factor receptor.

The epidermal growth factor receptor (EGFR) has an essential role in multiple signaling pathways, including cell proliferation and migration, through extracellular ligand binding and subsequent activation of its intracellular tyrosine kinase (TK) domain. The non-small cell lung cancer (NSCLC)-associated EGFR mutants, L858R and G719S, are constitutively active and oncogenic. They display sensitivity to TK inhibitors, including gefitinib and erlotinib. In contrast, the secondary mutation of the gatekeeper residue, T790M, reportedly confers inhibitor resistance on the oncogenic EGFR mutants. In this study, our biochemical analyses revealed that the introduction of the T790M mutation confers gefitinib resistance on the G719S mutant. The G719S/T790M double mutant has enhanced activity and retains high gefitinib-binding affinity. The T790M mutation increases the ATP affinity of the G719S mutant, explaining the acquired drug resistance of the double mutant. Structural analyses of the G719S/T790M double mutant, as well as the wild type and the G719S and L858R mutants, revealed that the T790M mutation stabilizes the hydrophobic spine of the active EGFR-TK conformation. The Met790 side chain of the G719S/T790M double mutant, in the apo form and gefitinib- and AMPPNP-bound forms, adopts different conformations that explain the accommodation of these ligands. In the L858R mutant structure, the active-site cleft is expanded by the repositioning of Phe723 within the P-loop. Notably, the introduction of the F723A mutation greatly enhanced the gefitinib sensitivity of the wild-type EGFR in vivo, supporting our hypothesis that the expansion of the active-site cleft results in enhanced gefitinib sensitivity. Taken together, our results provide a structural basis for the altered drug sensitivities caused by distinct NSCLC-associated EGFR mutations.

Impact of screening with thyroid ultrasonography in myasthenia gravis patients.

OBJECTIVES: This study was conducted to screen thyroid abnormality evaluated with ultrasonography (US) in patients with myasthenia gravis (MG) and investigate further when malignancy is suspected. METHODS: Thyroid screening using US was conducted in 162 patients with MG. In cases where malignancy was suspected, further investigations were performed. RESULTS: Abnormal US findings were detected in 125 of 162 patients with MG (72 patients with nodules, 74 patients with cysts, 27 patients with diffuse findings such as enlargement, atrophy, a hypoechoic pattern or a heterogenous echoic pattern, and 28 patients with calcification). From among these 125 subjects, 30 patients underwent further examinations such as needle aspiration cytology. As a result, six patients (3.7% of 162 cases) were positive for papillary carcinoma. The size of the carcinoma in three patients was <10 mm, yet the stage of thyroid carcinomas was high (stage III or IVa) in all six cases. CONCLUSIONS: Our data suggest that the prevalence of thyroid carcinoma in cases of MG may be higher than that of the general population. Furthermore, in patients with MG, there is a possibility that the stage of the carcinoma is higher even when the carcinoma is of a very small size. Patients with MG, when diagnosed, should be advised to undergo US screening of the thyroid because most cases of thyroid carcinoma are highly curable.

The role of B cells in multiple sclerosis: implications for B-cell-targeted therapy.

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system. Although most studies have emphasized the role of T cells in the pathogenesis of MS, increasing evidence supports the concept that B cells play a key role in the pathogenesis of MS, mainly in association with the deposition of antibodies and the activation of complement. Emerging pathophysiological findings of B-cell, follicle-like structures in the meninges of patients and observations of decreased interleukin (IL)-10 production from naïve B cells in MS have recently been reported. As more knowledge is gained of the pathophysiology of B cells in MS, the mechanisms of B-cell-mediated neuropharmacology of current therapy had been clarified as well. In this article, we review the increasing evidence that points to a link between B cells and MS, and also discuss the potential of B-cell-targeted therapy in MS.

Relationship between Barkhof criteria and the clinical features of multiple sclerosis in northern Japan.

We previously reported that the prevalence of multiple sclerosis (MS) in the Tokachi Province of Hokkaido increased from 8.6 to 13.1 per 100,000 individuals between 2001 and 2006. Here, we study the frequency of MS patients who fulfill the Barkhof criteria and identified their common features. All 47 subjects in our previous study, who fulfilled Poser's criteria, were included in this study. Of these, 33 satisfied the Barkhof criteria. In 2006, 9.2 per 100,000 MS patients fulfilled the Barkhof criteria; the percentage of patients who fulfilled these criteria was significantly higher among patients born after 1960 than among those born before 1960 (84.3% and 40.0%, respectively). The proportion of patients with conventional MS (C-MS) who fulfilled the Barkhof criteria was higher than that of patients with opticospinal MS (OS-MS) who fulfilled these criteria (93.9% and 71.4%, respectively). Longitudinally extensive spinal cord lesions (LESCLs) were not associated with the brain lesions defined in the Barkhof criteria (Barkhof brain lesions). In Tokachi Province, the increased percentage of MS patients who fulfill the Barkhof criteria was associated with increased C-MS incidence and an increase in the proportion of C-MS patients with Barkhof brain lesions among people born after 1960.

Serial combination therapy: is immune modulation in multiple sclerosis enhanced by initial immune suppression?

BACKGROUND: Although the concept that an initial course of immune-suppression facilitates subsequent immune-modulation (such as Th1 to Th2 deviation) is attractive for several autoimmune diseases, such a mechanism for serial-combination therapy has never been formally demonstrated. Recently, brief mitoxantrone induction-chemotherapy followed by immune-modulation with glatiramer acetate (GA) was significantly more effective at reducing multiple sclerosis disease activity than with GA alone. OBJECTIVE: To examine whether the benefit of initial immune suppression with mitoxantrone before GA treatment is associated with more efficient immune modulation. METHODS: IgG1/IgG4 GA-reactive antibody profiles, previously established as markers of GA-induced Th2 immune-deviation, were prospectively measured in vivo in patients treated with GA alone or with mitoxantrone induction therapy followed by GA. RESULTS: Significant and sustained increase in IgG4 antibodies (and the anticipated reversal of the IgG1/IgG4 ratio) was seen in patients treated with GA alone. Combination therapy resulted in lesser IgG4 induction (and no reversal of IgG1/IgG4 ratio). Thus, the enhanced efficacy of mitoxantrone-GA combination regimen was associated with decreased, rather than increased, efficiency of shifting the GA-reactive IgG1/IgG4 antibody profile. CONCLUSION: These results provide important insights into mechanisms of combination therapy and therapeutic strategies for autoimmune diseases.

Correlation between DJ-1 levels in the cerebrospinal fluid and the progression of disabilities in multiple sclerosis patients.

OBJECTIVES: DJ-1 plays a key role in the anti-oxidative stress function. Increasing evidence supports the role of oxidative stress in the pathogenesis of multiple sclerosis (MS). The aim of this study was to investigate whether the DJ-1 levels were increased in patients with MS and to examine its association with the progression of MS. METHODS: Quantitative immunoblot assays were performed to evaluate the DJ-1 level in serum and cerebrospinal fluid (CSF) collected from relapsing-remitting patients with MS (n = 29), disease controls subjects (n = 14), and healthy subjects (n = 44). RESULTS: No significant difference was observed in the serum DJ-1 level among the patients with MS, disease controls, and healthy controls. However, the CSF DJ-1 levels were significantly higher in the patients with MS than in the disease control subjects (P < 0.0001). A significant positive correlation was also found between the CSF DJ-1 levels and the Multiple Sclerosis Severity Score (P < 0.005, r = 0.501). CONCLUSIONS: These results show that the CSF DJ-1 levels are significantly increased in the CSF of patients with MS and that the CSF DJ-1 levels may be associated with the disease progression of MS. Therefore, DJ-1 possibly plays an important role in the pathogenesis of MS.

Expansion of CD4+CD28- T cells producing high levels of interferon-{gamma} in peripheral blood of patients with multiple sclerosis.

CD4(+) T cells that lack surface expression of the CD28 co-stimulatory molecule (CD4(+)CD28(-) T cells) were expanded in peripheral blood of patients with multiple sclerosis (MS) [5.20 +/- 1.67% vs 13.00 +/- 2.68% (healthy controls (HC) versus patients with MS)]. Both the CD4(+)CD28(+) and CD4(+)CD28(-) T-cell populations of patients with MS produced higher levels of interferon (IFN)-gamma compared with those in HC. In particular, the proportion of IFN-gamma(+) cells among CD4(+)CD28(-) T cells from patients with MS was considerably high. However, expression of co-stimulatory molecules including inducible costimulator (ICOS), activating natural killer receptors, or members of tumor necrosis factor receptor family that replace CD28 in CD4(+)CD28(-) T cells of patients with MS could not be identified. A unique subpopulation bearing the CD45RA(high)CCR7(-) phenotype was identified among the CD4(+)CD28(-) T cells of some patients with MS. Because only MS samples contained this CD45RA(high)CCR7(-) population attributed to terminally differentiated effector memory cells and lacked naive CD45RA(high)CCR7(+) cells, we suggest that CD4(+)CD28(-) T cells of patients with MS represent a cell population which is in more differentiated state than healthy subjects. In patients treated with IFN-beta-1b, IFN-gamma production from CD4(+)CD28(+) T cells was suppressed compared with that in untreated patients. On the contrary, in the CD4(+)CD28(-) population, production of IFN-gamma in IFN-beta-1b-treated patients was not significantly suppressed compared with that in untreated patients with MS. Thus, an additional treatment strategy that specifically targets this cell population may enhance the beneficial effect of IFN-beta on MS.

Increasing prevalence and incidence of multiple sclerosis in northern Japan.

BACKGROUND: We previously reported that prevalence of multiple sclerosis (MS) in Japan was 8.6/100,000 individuals in 2001. This was much higher than prevalence previously reported from Asian countries. A second epidemiologic survey was conducted to assess changes in MS prevalence and incidence over the last 30 years in Tokachi province of Hokkaido, the northernmost island of Japan. METHODS: The authors studied the frequency of MS in the community of Tokachi Province, where the population has stabilized between 350,000 and 360,000 over the last 30 years. The survey was conducted at the same institutions using the same methods as the first survey in 2001. RESULTS: On March 31, 2006, 47 subjects satisfied Poser's criteria for MS. The prevalence rate increased from 8.6 to 13.1/100,000 individuals between 2001 and 2006. The prevalence of conventional MS (C-MS) increased in five years although the prevalence of optic-spinal MS (OS-MS) did not increase. The mean annual incidence increased from 0.15 (1975-1989) to 0.68 (1990-2004). CONCLUSIONS: The results show the highest MS prevalence in Asia; the increase in MS prevalence in Tokachi Province may be due to increased incidence after 1990.

Effect of high fat diet on NKT cell function and NKT cell-mediated regulation of Th1 responses.

Diet is one of the important factors that modulate immune responses. In the present study, we have examined the capacity of dietary lipids to modify immune responses in mice and we have investigated the contribution of glycolipid-reactive natural killer T (NKT) cells in this process. Mice fed, high fat diet (HFD; 21.2% fat, 0.20% cholesterol) for 3 weeks, as compared with mice fed standard fat diet (SFD; 4.3% fat, 0.03% cholesterol), showed significantly reduced interferon-gamma production in sera at 6 or 12 h after intraperitoneal injection of an NKT cell ligand, alpha-galactosylceramide. In contrast, production of interleukin-13 was significantly higher at 2 and 6 h in HFD fed mice compared with mice on SFD. No difference was detected in the serum interleukin-4 levels between these two groups of animals. The proportion of NKT cells in spleen and liver was reduced in mice fed HFD compared with those on SFD. In addition, activation of NKT cells assessed by up-regulation of CD69 was suppressed specifically in liver from mice fed HFD. Recall responses of conventional T cells and delayed-type hypersensitivity (Th1 type) against ovalbumin were significantly suppressed in mice fed HFD in comparison with those fed SFD. This suppression was not observed in CD1d-/- mice, suggesting that NKT cells in mice fed HFD played a role in suppressing Th1 responses. Taken together, our findings suggest a critical link between NKT cells, dietary lipid and adaptive immune responses.

APOE epsilon variation in multiple sclerosis susceptibility and disease severity: some answers.

BACKGROUND: Previous studies have examined the role of APOE variation in multiple sclerosis (MS), but have lacked the statistical power to detect modest genetic influences on risk and disease severity. The meta- and pooled analyses presented here utilize the largest collection, to date, of MS cases, controls, and families genotyped for the APOE epsilon polymorphism. METHODS: Studies of MS and APOE were identified by searches of PubMed, Biosis, Web of Science, Cochrane Review, and Embase. When possible, authors were contacted for individual genotype data. Meta-analyses of MS case-control data and family-based analyses were performed to assess the association of APOE epsilon genotype with disease risk. Pooled analyses of MS cases were also performed to assess the influence of APOE epsilon genotype on disease severity. RESULTS: A total of 22 studies (3,299 MS cases and 2,532 controls) were available for meta-analysis. No effect of epsilon2 or epsilon4 status on MS risk was observed (summary OR 1.14, 95% CI 0.96-1.34 and OR 0.89, 95% CI 0.78-1.01). Results obtained from analyses of APOE genotypes in 1,279 MS families were also negative (p = 0.61). Finally, results from pooled analyses of 4,048 MS cases also argue strongly that APOE epsilon status does not distinguish a relapsing-remitting from primary progressive disease course, or influence disease severity, as measured by the Expanded Disability Status Scale and disease duration. CONCLUSION: Overall, these findings do not support a role for APOE in multiple sclerosis, and underscore the importance of using large sample sizes to detect modest genetic effects, particularly in studies of genotype-phenotype relationships.

Polymorphisms of apolipoprotein E and Japanese patients with multiple sclerosis.

The relation between apolipoprotein (APOE) gene polymorphisms and disease progression of multiple sclerosis (MS) is controversial. The present study was designed to investigate the relation between APOE gene polymorphisms and Japanese patients with MS. We analysed the frequencies of APOE gene polymorphisms in 135 MS patients and 134 healthy controls, using PCR-RFLP. The results showed no significant differences in the distribution of APOE gene polymorphisms between MS patients and controls. With regard to disease progression, there was no association between APOE gene polymorphisms and epsilon4 allele positivity and disease progression index (EDSS/ years). Furthermore, in patients with more than 10 years of disease onset, there were no significant differences between the frequencies of epsilon4 allele and patients with EDSS of more than 6. Although the low rate of epsilon4 allele in Japan should be taken into consideration, our results showed no relation between APOE gene polymorphisms and Japanese patients with MS.

HLA-related subpopulations of MS in Japanese with and without oligoclonal IgG bands. Human leukocyte antigen.

BACKGROUND: Oligoclonal IgG bands (OCB) are present in most patients with MS in Western countries; however, in Japanese MS patients, the OCB-positive rate is not as high. A relationship between immunogenetic backgrounds, namely, human leukocyte antigen (HLA) DR2 and DR4 positivity, and OCB production in MS patients from Hokkaido, the northernmost island of Japan, has been previously suggested by the authors. OBJECTIVES: To investigate the role of OCB in Japanese MS and to verify the interaction between immunogenetic backgrounds and OCB positivity. METHODS: OCB, DR2(15), and DR4 positivity were studied in 45 patients with newly diagnosed MS. In addition to confirming the authors' previous findings, the clinical and demographic features, MRI findings, OCB positivity, and DRB1*15 and DRB1*04 polymorphisms of an expanded data set of 99 MS patients were investigated by using multivariate analysis. Patients with opticospinal MS (OS-MS) were excluded from this study. RESULTS: A relatively low OCB-positive rate (53.3%), HLA-DR15 association with OCB-positive MS (p = 0.0044), and DR4 association with OCB-negative MS (p = 0.0410) were confirmed. DR15 was not associated with OCB-negative MS. Demographic features, disease course, and disability were similar in the OCB-negative and OCB-positive group, whereas there was a preponderance of women in the OCB-positive group. An independent negative association of DRB1*0405 (p = 0.0021, adjusted odds ratio = 0.21) with OCB positivity was found. CONCLUSIONS: MS is heterogeneous in its association with HLA alleles, and based on the immunogenetic differences, the MS patients in this population include at least two HLA-related subpopulations with and without OCB.

An examination of the association between beta2 adrenergic receptor polymorphisms and multiple sclerosis.

In multiple sclerosis (MS), beta-adrenergic receptor densities on peripheral blood mononuclear cells are enhanced, while the astrocytes present in plaques lack beta2 adrenergic receptor (beta2AR) expression. This differentially altered expression suggests that beta2ARs may influence the pathogenesis of MS. In the present study, we investigated the association of polymorphisms of the beta2AR gene with the occurrence of MS. Our results showed no significant differences in the distribution of the polymorphisms between MS patients overall and control subjects. Furthermore, no association was observed between the presence of beta2AR gene polymorphisms and clinical characteristics, such as age at disease onset and disease severity. While a trend towards an increase of the Gly allele frequency in codon 16 was observed in the secondary-progressive MS, this result was not significantly different from that observed in relapsing-remitting MS patients or control subjects. Together, our findings suggest that the presence of beta2AR gene polymorphisms may be inconclusive in the susceptibility to MS or in the clinical characteristics of Japanese patients with MS and, therefore, need further studies.

Prostaglandin E1 protects cultured spinal neurons against the effects of nitric oxide toxicity.

The effects of prostaglandin (PG) E(1) on NO neurotoxicity were examined using rat cultured spinal neurons. Rat cultured spinal neurons exposed to the NO donor, 2,2'-(hydroxynitrosohydrazono) bis-ethanamine (NOC18), showed neurotoxic effects that were accompanied by apoptotic nuclear change, free radical generation, a reduction in glutathione, and mitochondrial dysfunction. PGE(1), at concentrations of 1-100 nM, protected cultured spinal neurons from NO toxicity by reversing the oxidative and pro-apoptotic properties elicited by NOC18 exposure. The administration of PGE(1) increased the intracellular cyclic AMP (cAMP) levels in cultured spinal neurons. In addition, reverse transcriptase-polymerase chain reaction (RT-PCR) analysis confirmed the existence of EP4, a cAMP-elevating PGE receptor, in cultured spinal neurons. The protective effects of PGE(1) against NO neurotoxicity was partially blocked by an inhibitor of MEK [the mitogen-activated protein kinase (MAPK)/extracellular-signal-regulated kinase (ERK) kinase], suggesting that the MAPK/ERK pathway may play a significant role in the activity of PGE(1). PGE(1) up-regulated the expression of the anti-apoptotic protein, Bcl-2, as determined by Western blot analysis. PGE(1) also induced the expression of thioredoxin in cultured spinal neurons. Our data indicate that PGE(1) exerts a protective action against NO neurotoxicity in cultured spinal neurons, and suggests a therapeutic potential of PGE(1) against spinal cord disease, such as amyotrophic lateral sclerosis.

Reverse seroconversion of hepatitis B virus after hematopoietic stem cell transplantation.

Hepatitis B virus (HBV) reactivation in patients previously positive for hepatitis B surface antibody (HBsAb), so-called reverse seroconversion, has been considered to be a rare complication after hematopoietic stem cell transplantation (HSCT). We experienced two patients who developed reverse seroconversion among nine who were HBsAb positive and Hepatitis B core antibody (HBcAb) positive before HSCT; one after autologous bone marrow transplantation (BMT) and another after allogeneic peripheral blood stem cell transplantation (PBSCT). We reviewed the literature and considered that reverse seroconversion of HBV after HSCT is not uncommon among HBsAb positive recipients. The use of corticosteroids, the lack of HBsAb in donor, and a decrease in serum HBsAb and HBcAb levels may predict reverse seroconversion after HSCT.

Heat shock protein 70 gene polymorphism in Japanese patients with multiple sclerosis.

Despite the strength of the association of multiple sclerosis (MS) and human leukocyte antigen (HLA)-DR2, other genetic elements could have a role in the pathophysiology of MS. We investigated possible associations with polymorphic susceptibility genes located within the HLA complex, i.e., heat-shock protein (HSP)70-1, HSP70-2, and HSP70-hom in Japanese patients with MS. Furthermore, we analyzed the influence of HSP70 gene polymorphisms on the severity of the disease, clinical course, magnetic resonance imaging findings, and oligoclonal bands in the cerebrospinal fluid, and HLA in MS patients. The results of the present study indicated that there were no significant differences in the distribution of all HSP70 genotypes and allele frequencies between Japanese MS patients and controls. In MS patients, there were no associations between HSP70 gene polymorphisms and the clinical data. Moreover, there were no significant differences in HSP70 genotype or allele frequencies between MS patients positive for HLA-DRB1*1501 alleles and matched controls. Our data indicate that HSP70 gene polymorphisms are not relevant in the susceptibility to or the severity of Japanese MS patients.

Genetic polymorphisms of IL-1beta and IL-1 receptor antagonist in association with multiple sclerosis in Japanese patients.

In the present study, we have investigated the association of specific polymorphisms of the interleukin (IL)-1beta and IL-1 receptor antagonist (ra) gene with both the susceptibility to and the clinical characteristics of multiple sclerosis (MS) in Japanese patients. We collected and analyzed DNA from 98 MS patients and 104 healthy controls for distribution of IL-1beta or IL-1ra polymorphisms. Our results show no significant differences in the distribution of the polymorphisms between MS patients and controls. Furthermore, no association was observed between IL-1beta or IL-1ra polymorphisms and clinical characteristics, such as age at disease onset, clinical course and severity. Together, our findings suggest that IL-1beta or IL-1ra gene polymorphisms may not be relevant in the susceptibility to MS or the clinical characteristics of Japanese patients with MS.