Satoshi Ito

University of Tsukuba, Tsukuba, Ibaraki, Japan

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Publications (130)406.81 Total impact

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    ABSTRACT: Rheumatoid arthritis (RA) is a chronic inflammatory disease accompanied by many complications, and serious infections are associated with many of the advanced therapeutics used to treat it. We assessed serum procalcitonin (PCT) levels to distinguish bacterial infection from other complications in patients with RA. One hundred eighteen patients experiencing an RA flare, noninfectious complication of RA or its treatment, nonbacterial infection, or bacterial infection were studied. Serum PCT concentrations were determined with a chemiluminescent enzyme immunoassay. All patients experiencing an RA flare showed negative PCT levels (≤ 0.1 ng/ml; n = 18). The PCT level was higher in the bacterial infection group (25.8% had levels ≥ 0.5 ng/ml) than in the other 3 groups (0.0-4.3% had levels ≥ 0.5 ng/ml) and the difference was significant among groups (p = 0.003). Conversely, no statistically significant difference was observed among the groups with C-reactive protein (CRP) concentration ≥ 0.3 mg/dl (p = 0.513), white blood cell (WBC) count > 8500/mm(3) (p = 0.053), or erythrocyte sedimentation rate (ESR) > 15 mm/h (p = 0.328). The OR of high PCT level (≥ 0.5 ng/ml) for detection of bacterial infection was 19.13 (95% CI 2.44-149.78, p = 0.005). Specificity and positive likelihood ratio of PCT ≥ 0.5 ng/ml were highest (98.2% and 14.33, respectively) for detection of bacterial infection, although the sensitivity was low (25.8%). Serum PCT level is a more specific marker for detection of bacterial infection than either CRP, ESR, or WBC count in patients with RA. High PCT levels (≥ 0.5 ng/ml) strongly suggest bacterial infection. However, PCT < 0.5 ng/ml, even if < 0.2 ng/ml, does not rule out bacterial infection and physicians should treat appropriately.
    No preview · Article · Jul 2012 · The Journal of Rheumatology
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    ABSTRACT: Objective To compare reasons for discontinuation and drug retention rates per reason among anticytokine therapies, infliximab, etanercept and tocilizumab, and the risk of discontinuation of biological agents due to adverse events (AE) in patients with rheumatoid arthritis (RA). Method This prospective cohort study included Japanese RA patients who started infliximab (n=412, 636.0 patient-years (PY)), etanercept (n=442, 765.3 PY), or tocilizumab (n=168, 206.5 PY) as the first biological therapy after their enrolment in the Registry of Japanese Rheumatoid Arthritis Patients for Long-term Safety (REAL) database. Drug retention rates were calculated using the Kaplan–Meier method. To compare risks of drug discontinuation due to AE for patients treated with these biological agents, the Cox proportional hazard model was applied. Results The authors found significant differences among the three therapeutic groups in demography, clinical status, comorbidities and usage of concomitant drugs. Development of AE was the most frequent reason for discontinuation of biological agents in the etanercept and tocilizumab groups, and the second most frequent reason in the infliximab group. Discontinuation due to good control was observed most frequently in the infliximab group. Compared with etanercept, the use of infliximab (HR 1.69; 95% CI 1.14 to 2.51) and tocilizumab (HR 1.98; 95% CI 1.04 to 3.76) was significantly associated with a higher risk of discontinuation of biological agents due to AE. Conclusions Reasons for discontinuation are significantly different among biological agents. The use of infliximab and tocilizumab was significantly associated with treatment discontinuation due to AE compared with etanercept.
    No preview · Article · Apr 2012 · Annals of the rheumatic diseases
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    ABSTRACT: A 36-year-old woman was diagnosed with systemic lupus erythematosus (SLE). Seven days after beginning glucocorticoid treatment, she developed reduced visual acuity, and atypical severe central serous chorioretinopathy (CSC) was confirmed. Since glucocorticoid use is an important risk factor for CSC, the PSL was reduced, tacrolimus was added, and the visual acuity improved rapidly. Reduction in glucocorticoid combined with the use of immunosuppressive agents is one option for preventing a deterioration in atypical severe CSC while still controlling SLE.
    No preview · Article · Mar 2012 · Modern Rheumatology
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    ABSTRACT: To investigate associations between continuous treatments with tumor necrosis factor (TNF) antagonists and risk for developing serious infections (SIs) over 3 years in Japanese patients with rheumatoid arthritis (RA) enrolled in the Registry of Japanese RA Patients for Long-Term Safety (REAL) database. We analyzed 727 RA patients who had started either infliximab or etanercept (the anti-TNF group; 1,480.1 patient-years [PY]) and 571 RA patients who had started conventional nonbiologic disease-modifying antirheumatic drugs (the unexposed group; 1,104.1 PY) at the time of enrollment in the REAL. We assessed the occurrence of SIs within a 3-year observation period, including the period after switching to other TNF antagonists, and all SIs, unlimited to the first one in each patient as reported in other studies, to evaluate the real safety of TNF antagonists in daily practice. The incidence rate of SIs per 100 PY was 5.54 (95% confidence interval [95% CI] 4.44-6.84) in the anti-TNF group and 2.72 (95% CI 1.87-3.83) in the unexposed group. Poisson regression analysis revealed that the relative risk (RR) of continuous use of TNF antagonists for SIs after adjusting for baseline and time-dependent covariates was significantly elevated both overall (1.97, 95% CI 1.25-3.19) and for the first year (2.40, 95% CI 1.20-5.03), but not for the second and third years combined (1.38, 95% CI 0.80-2.43). The adjusted RR for SIs of etanercept compared to infliximab was not significantly elevated. Continuous anti-TNF therapy was significantly associated with increased risks for developing SIs during, but not after, the first year.
    Full-text · Article · Mar 2012
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    ABSTRACT: Objectives To examine the improvement in health-related quality of life (HRQOL) in association with disease activity in myeloperoxidase (MPO)-antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis patients treated with cyclophosphamide plus prednisolone. Methods According to the Japanese Patients with MPO-ANCA-Associated Vasculitis (JMAAV) study protocol, a total of 48 patients with newly diagnosed MPO-ANCA-associated vasculitis received a standardized cyclophosphamide plus prednisolone regimen, and their clinical courses were followed for 18 months following their entry into the study. Disease activity was assessed using the Birmingham Vasculitis Activity Score (BVAS) 2003. HRQOL was assessed using MOS Short-Form 36 (SF-36) v2. BVAS new/worse, BVAS persistent, and SF-36 domain scores (norm-based) were calculated for the 32 eligible patients. Results The mean SF-36 domain scores were significantly lower than the Japanese general population norm. Stepwise multiple linear regression analysis showed that the presence of new or worsening features of the nervous system was significantly associated with a deterioration in physical function. During the 18 months of follow-up, there were significant improvements in BVAS new/worse and all SF-36 domains except for general health and role emotional. Conclusion MPO-ANCA-associated vasculitis patients experienced a considerable deterioration in HRQOL. The standardized cyclophosphamide plus prednisolone regimen of the JMAAV study induced remission in the majority of patients, and the induction of remission accompanied a recovery in HRQOL.
    No preview · Article · Feb 2012 · Modern Rheumatology
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    ABSTRACT: Systemic lupus erythematosus (SLE) is an autoimmune disease that causes multiple organ damage. Although recent genome-wide association studies (GWAS) have contributed to discovery of SLE susceptibility genes, few studies has been performed in Asian populations. Here, we report a GWAS for SLE examining 891 SLE cases and 3,384 controls and multi-stage replication studies examining 1,387 SLE cases and 28,564 controls in Japanese subjects. Considering that expression quantitative trait loci (eQTLs) have been implicated in genetic risks for autoimmune diseases, we integrated an eQTL study into the results of the GWAS. We observed enrichments of cis-eQTL positive loci among the known SLE susceptibility loci (30.8%) compared to the genome-wide SNPs (6.9%). In addition, we identified a novel association of a variant in the AF4/FMR2 family, member 1 (AFF1) gene at 4q21 with SLE susceptibility (rs340630; P = 8.3×10(-9), odds ratio = 1.21). The risk A allele of rs340630 demonstrated a cis-eQTL effect on the AFF1 transcript with enhanced expression levels (P<0.05). As AFF1 transcripts were prominently expressed in CD4(+) and CD19(+) peripheral blood lymphocytes, up-regulation of AFF1 may cause the abnormality in these lymphocytes, leading to disease onset.
    Full-text · Article · Jan 2012 · PLoS Genetics
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    ABSTRACT: Methylation status of the cytokine genes may play a role in the pathogenesis of inflammatory diseases, such as rheumatoid arthritis (RA) and chronic periodontitis (CP). This study was undertaken to evaluate whether the DNA methylation profile of the interleukin-6 (IL-6) gene promoter was unique to individuals with RA and CP. The study participants consisted of 30 patients with RA, 30 patients with CP, and 30 age-, sex-, and smoking status-balanced healthy controls. Genomic DNA isolated from peripheral blood was modified by sodium bisulfite and analyzed for DNA methylation levels of IL-6 gene with direct sequencing. Levels of IL-6 were determined by an enzyme-linked immunosorbent assay. The region of IL-6 gene promoter from -1200 to +27 bp was shown to contain 19 CpG motifs. The methylation levels of the CpG motif at -74 bp were significantly lower in patients with RA and CP than those in controls (P = 0.0001). Both levels of serum IL-6 and IL-6 production by mononuclear cells were significantly different between individuals with and without the methylation at -74 bp (P = 0.03). The +19 bp motif exhibited differential levels of the methylation among the groups, which was not associated with serum levels of IL-6. The other 17 CpG motifs exhibited comparable levels of the methylation between the groups. These results suggest that hypomethylated status of a single CpG in the IL-6 promoter region may lead to increased levels of serum IL-6, implicating a role in the pathogenesis of RA and CP.
    No preview · Article · Nov 2011 · Journal of Periodontology
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    ABSTRACT: Interstitial lung disease (ILD) is induced by various factors in humans. However, the exact mechanism of ILD remains elusive. This study sought to determine the role of natural killer (NK) 1.1(+) γδT cells in ILD. The injection of IL-18 plus IL-2 (IL-18/IL-2) into C57BL6 (B6) mice induced acute ILD that resembled early-stage human ILD. An accumulation of NK1.1(+) γδT cells similar to NK cells was evident in the lungs. The T Cell Receptor (TCR) Vγ and Vδ repertoires of NK1.1(+) γδT cells indicated polyclonal expansion. The expression of IL-2 receptor β (Rβ) and IL-18Rβ in NK1.1(+) γδT cells was higher than in NK1.1(-) γδT cells. IL-18/IL-2 stimulated the proliferation of NK1.1(+) γδT cells, but not NK1.1(-) γδT cells. The IL-18/IL-2-stimulated NK1.1(+) γδT cells produced higher concentrations of IFN-γ than did NK1.1(-) γδT cells. Moreover, NK1.1(+) γδT and NK1.1(-) γδT cells constituted completely different cell populations. The IL-18/IL-2-induced ILD was milder in TCRδ(-/-) and IFN-γ(-/-) mice, compared with B6 mice. Furthermore, cell-transfer experiments demonstrated that NK1.1(+) γδT cells could induce the expansion of NK cells and IFN-γ mRNA in the lung by IL-18/IL-2. Our results suggest that NK1.1(+) γδT cells function as inflammatory mediators in the early phase of IL-18/IL-2-induced ILD.
    Preview · Article · Sep 2011 · American Journal of Respiratory Cell and Molecular Biology
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    ABSTRACT: Human six-transmembrane epithelial antigen of prostate4 (STEAP4), an ortholog of mouse tumor necrosis factor-α-induced adipose-related protein (TIARP), plays a role in tumor necrosis factor (TNF)-dependent arthritis models. However, its role in rheumatoid arthritis (RA) is still obscure. This study explored such a role for STEAP4. The expressions of STEAP4, TNFα, and IL-6 were compared in synovia of RA and osteoarthritis patients. STEAP4 induction was examined in TNFα-stimulated fibroblast-like synoviocytes (FLS) in vitro. FLS (with/without TNFα stimulation) were also analyzed for IL-6 expression after STEAP4 knockdown, using siRNA or transfection with STEAP4-plasmid DNA. IL-8, cell proliferation, and apoptosis were also evaluated in STEAP4-overexpressing FLS. The expression of STEAP4 in joints correlated with TNFα expression, specifically in RA synovium. In the cultured FLS, STEAP4 protein expression was augmented by TNFα activation, and localized in endosomal/lysosomal compartments. STEAP4 downregulation by siRNA enhanced the expression of IL-6 mRNA, while STEAP4 overexpression suppressed IL-6 and IL-8 expression, inhibited cell proliferation, and induced apoptosis via caspase-3. The results indicated that human STEAP4 is regulated by TNFα in synovium, where it controls IL-6 secretion and proliferation of FLS, suggesting that STEAP4 might potentially suppress the pathogenesis of TNFα-induced arthritis such as RA.
    No preview · Article · Jun 2011 · Modern Rheumatology
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    ABSTRACT: Although large-scale studies established many susceptibility genes to systemic lupus erythematosus (SLE), effect of each gene is not sufficiently large to be used alone to identify individuals with strong genetic predisposition. In this study, we analyzed the cumulative number of risk alleles at eight established susceptibility loci, HLA-DRB1, IRF5, STAT4, BLK, TNFAIP3, TNIP1, FCGR2B and TNFSF13, in 282 Japanese female SLE and 222 healthy female controls. The average number of risk alleles was significantly increased in SLE (8.07±1.60) than healthy controls (7.02±1.64) (P=1.63 × 10(-12)). Significant gene-gene interaction was not detected. When the subjects carrying seven risk alleles were used as a reference, the odds ratio (OR) for individuals carrying 10 and 11-13 risk alleles were 4.17 (95% confidence interval (CI) 1.89-9.19, P=0.0002) and 8.77 (95% CI 1.92-40.0, P=0.0016), respectively. In contrast, subjects with ≤4 risk alleles were significantly decreased in SLE (OR 0.15, CI 0.03-0.67, P=0.007). The proportion of the patients with neurologic disorder was significantly increased in those carrying ≥10 risk alleles than those with <10 (OR 2.30, CI 1.09-4.83, P=0.025). This study suggested that the cumulative number of risk alleles may efficiently distinguish groups with high and low genetic predisposition to SLE and its severe manifestation.
    No preview · Article · May 2011 · Journal of Human Genetics
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    ABSTRACT: To compare tumor necrosis factor-α (TNF-α) inhibitors to nonbiological disease-modifying antirheumatic drugs (DMARD) for the risk of serious infection in Japanese patients with rheumatoid arthritis (RA). Serious infections occurring within the first year of the observation period were examined using the records for patients recruited to the Registry of Japanese Rheumatoid Arthritis Patients for Longterm Safety (REAL), a hospital-based prospective cohort of patients with RA. The analysis included 1144 patients, 646 of whom were treated with either infliximab or etanercept [exposed group: 592.4 patient-years (PY)]. The remaining 498 patients received nonbiological DMARD with no biologics (unexposed group: 454.7 PY). In the unexposed group, the incidence rate for all serious adverse events (SAE) was 9.02/100 PY and for serious infections, 2.64/100 PY. In the exposed group, SAE occurred in 16.04/100 PY and serious infections in 6.42/100 PY. The crude incidence rate ratio comparing serious infections in the exposed group with the unexposed group was 2.43 (95% CI 1.27-4.65), a significant increase. A multivariate analysis revealed that the use of TNF inhibitors is a significant independent risk factor for serious infection (relative risk 2.37, 95% CI 1.11-5.05, p = 0.026). Our study has provided the first epidemiological data on Japanese patients with RA for the safety of TNF inhibitors compared to nonbiological DMARD for up to 1 year of treatment. Anti-TNF therapy was associated with a significantly increased risk for serious infections, compared to treatment with nonbiological DMARD.
    No preview · Article · Apr 2011 · The Journal of Rheumatology
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    ABSTRACT: SPI1, also referred to as PU.1, is an Ets family transcription factor that interacts with IRF2, IRF4, and IRF8. In view of the significance of the type I interferon pathway in systemic lupus erythematosus (SLE), this study was undertaken to investigate a possible association between SPI1 polymorphisms and SLE. A case-control association study was performed using 6 tag single-nucleotide polymorphisms (SNPs), as well as a SNP located upstream of SPI1 previously found to be associated with acute myelogenous leukemia, in 400 Japanese patients with SLE and 450 healthy controls. Resequencing of all exons and known regulatory regions was performed to identify functional polymorphisms. Association of genotype and SPI1 expression was examined using the GENEVAR database and reporter assays. A significant association was detected in 2 SNPs in intron 2 (rs10769258 and rs4752829) (P = 0.005 and P = 0.008, respectively, under the dominant model). The association was stronger in patients with nephropathy. Resequencing identified a potentially functional polymorphism in the 3'-untranslated region (3'-UTR), rs1057233, which was in strong linkage disequilibrium with the SNPs in intron 2. The number of risk alleles at rs1057233 was strongly correlated with SPI1 messenger RNA (mRNA) level in the database analysis (P = 0.0002), and was confirmed by a reporter assay. Interestingly, rs1057233 alters a target sequence for microRNA hsa-miR-569 (miR-569). Transfection experiments demonstrated that miR-569 inhibits expression of a reporter construct with the 3'-UTR sequence containing the nonrisk allele but not the risk allele. Our findings indicate that a SNP in the 3'-UTR of SPI1 is associated with elevated SPI1 mRNA level and with susceptibility to SLE.
    Full-text · Article · Mar 2011 · Arthritis & Rheumatology
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    ABSTRACT: The Toll-like receptor 7 (TLR7) gene, encoded on human chromosome Xp22.3, is crucial for type I interferon production. A recent multicenter study in East Asian populations, comprising Chinese, Korean and Japanese participants, identified an association of a TLR7 single-nucleotide polymorphism (SNP) located in the 3' untranslated region (3' UTR), rs3853839, with systemic lupus erythematosus (SLE), especially in males, although some difference was observed among the tested populations. To test whether additional polymorphisms contribute to SLE in Japanese, we systematically analyzed the association of TLR7 with SLE in a Japanese female population. A case-control association study was conducted on eight tag SNPs in the TLR7 region, including rs3853839, in 344 Japanese females with SLE and 274 healthy female controls. In addition to rs3853839, two SNPs in intron 2, rs179019 and rs179010, which were in moderate linkage disequilibrium with each other (r2 = 0.53), showed an association with SLE (rs179019: P = 0.016, odds ratio (OR) 2.02, 95% confidence interval (95% CI) 1.15 to 3.54; rs179010: P = 0.018, OR 1.75, 95% CI 1.10 to 2.80 (both under the recessive model)). Conditional logistic regression analysis revealed that the association of the intronic SNPs and the 3' UTR SNP remained significant after we adjusted them for each other. When only the patients and controls carrying the risk genotypes at the 3' UTR SNP position were analyzed, the risk of SLE was significantly increased when the individuals also carried the risk genotypes at both of the intronic SNPs (P = 0.0043, OR 2.45, 95% CI 1.31 to 4.60). Furthermore, the haplotype containing the intronic risk alleles in addition to the 3' UTR risk allele was associated with SLE under the recessive model (P = 0.016, OR 2.37, 95% CI 1.17 to 4.80), but other haplotypes were not associated with SLE. The TLR7 intronic SNPs rs179019 and rs179010 are associated with SLE independently of the 3' UTR SNP rs3853839 in Japanese women. Our findings support a role of TLR7 in predisposition for SLE in Asian populations.
    Full-text · Article · Mar 2011 · Arthritis research & therapy

  • No preview · Article · Feb 2011 · Modern Rheumatology
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    ABSTRACT: It is reported that in salivary glands of Sjögren's syndrome (SS), interferon gamma (IFNγ) and IFNγ-inducible genes containing signal transducers and activators of transcription 1 (STAT1) are upregulated and play a crucial role in the pathogenesis of SS. The aim of this study is to clarify which phosphorylation of STAT1, serine727 (Ser(727)) or tyrosine701 (Tyr(701)) of STAT1, is important for IFNγ signaling and IFNγ-induced apoptosis in salivary gland cells. We established STAT1 Tyr(701) variant (tyrosine to phenylalanine; Y701F) and STAT1 Ser(727) variant (serine to alanine; S727A), which were transfected into human salivary gland (HSG) cells. HSG cells transfected with these mutant-STAT1 were analyzed on the expression of IFNγ-inducible genes and apoptosis after stimulation with IFNγ. In Y701F mutant-STAT1 transfected HSG cells (Ser(727)-dominant HSG cells), IFNγ-inducible genes such as IP10, IRF1, and Fas expression were increased after stimulation with IFNγ. In Ser(727)-dominant HSG cells, the induction of apoptosis after stimulation with IFNγ was also increased compared with S727A mutant-STAT1 transfected HSG cells (Tyr(701)-dominant HSG cells). Phosphorylation of Ser(727) in STAT1 might be more important in IFNγ signaling and the induction of apoptosis in HSG cells than phosphorylation of Tyr(701). Accordingly, we propose that phosphorylation of Ser(727) in STAT1 could be a potentially suitable new therapeutic target for SS patients to prevent the destruction of salivary glands.
    No preview · Article · Feb 2011 · International Journal of Rheumatic Diseases
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    ABSTRACT: Periodontopathic bacteria have been implicated as contributory to the etiology of rheumatoid arthritis (RA). Anticyclic citrullinated peptide (CCP) antibodies and rheumatoid factor (RF) were shown to be associated with RA. This study examines whether serum levels of antibodies to periodontopathic bacteria may affect clinical and laboratory profiles of RA. The study participants consisted of 80 patients with RA, and 38 age-, sex-, smoking status-, and periodontal condition-balanced healthy controls. After periodontal and rheumatologic examination, serum levels of immunoglobulin G (IgG) antibodies to Porphyromonas gingivalis (Pg), Prevotella intermedia, Aggregatibacter actinomycetemcomitans (Aa) (previously Actinobacillus actinomycetemcomitans), and Eikenella corrodens (Ec) and those of anti-CCP antibodies and RF were determined by an enzyme-linked immunosorbent assay. Patients with RA showed significantly higher levels of anti-Pg and anti-CCP antibodies than controls (P = 0.04 and P <0.0001). In contrast, IgG responses to Aa and Ec in patients with RA were significantly lower than those in controls (P <0.0001 and P = 0.0001). Multiple logistic regression analysis revealed a significant association of anti-Pg and anti-Aa IgG responses with RA, after adjustment for age, sex, and smoking (P = 0.005 and P = 0.02). Anti-Pg titer displayed a significant correlation with RF levels, probing depth, and clinical attachment level (P = 0.03, P = 0.03, and P = 0.02). These results suggest that serum levels of anti-Pg IgG antibodies were associated with RA, and might affect serum levels of RF and periodontal condition in patients with RA.
    No preview · Article · Feb 2011 · Journal of Periodontology
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    ABSTRACT: The aim of this study was to clarify the role of the immune response to muscarinic type 3 receptor (M3R) in the pathogenesis of Sjögren's syndrome (SS). M3R(-/-) mice were immunized with murine M3R peptides and their splenocytes were inoculated into Rag1(-/-) (M3R(-/-)→Rag1(-/-)) mice. M3R(-/-)→Rag1(-/-) mice had high serum levels of anti-M3R antibodies and low saliva volume. Histological examination showed marked infiltration of mononuclear cells in the salivary glands and immunohistochemistry demonstrated that the majority of these cells were CD4(+) T cells with a few B cells and several IFN-γ- and IL-17-producing cells. Apoptotic cells were present in the salivary glands of M3R(-/-)→Rag1(-/-) mice. Moreover, transfer of only CD3(+) T cells from M3R(-/-) immunized with M3R peptides into Rag1(-/-) mice resulted in cell infiltration and destruction of epithelial cells in the salivary glands, suggesting that M3R reactive CD3(+) T cells play a pathogenic role in the development of autoimmune sialoadenitis. Our findings support the notion that the immune response to M3R plays a crucial role in the pathogenesis of SS-like autoimmune sialoadenitis.
    No preview · Article · Dec 2010 · Journal of Autoimmunity
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    ABSTRACT: Methotrexate (MTX) is indispensable for the treatment of rheumatoid arthritis (RA). However, a small number of patients treated with MTX occasionally encounter some life-threatening events, including myelosuppression. Renal insufficiency, one of risk factors for these events, is difficult to assess because the serum creatinine concentration level and estimated glomerular filtration rate are sometimes inaccurately determined in aged RA patients. As a better indicator to evaluate this pathology, we measured the serum cystatin-C (Cys-C) level in 78 RA patients ≥ 50 years who were treated with MTX and observed for a year. The measurement achieved successful screening of two patients with leukocytopenia, one with interstitial lung disease (ILD), and two with liver dysfunction. An additional four referral inpatients with MTX-induced adverse events (three with pancytopenia, one with ILD) were enrolled for analysis, amounting to 82 patients. The logistic regression analysis showed that a correlation was observed between myelotoxicity and serum Cys-C level (elevation per 0.1 mg/dl; odds ratio 2.34, 95% confidence interval 1.08-5.09, p = 0.03). In conclusion, elderly RA patients potentially have subclinical renal insufficiency detected by the serum Cys-C concentration level. The elevated level of serum Cys-C is a more sensitive indicator to predict MTX-induced myelotoxicity than that of serum creatinine.
    No preview · Article · Dec 2010 · Modern Rheumatology
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    ABSTRACT: Imatinib and nilotinib are inhibitors that selectively target a set of protein tyrosine kinases, including abelson kinase (Abl), together with the chimeric oncoprotein, breakpoint cluster region-abelson kinase (Bcr-Abl), as well as stem cell factor receptor (KIT), platelet-derived growth factor receptor (PDGFR), discoidin domain receptor (DDR), and colony stimulating factor-1 receptor (CSF-1R). The aim of the present study was to investigate whether imatinib or nilotinib was effective against arthritis in the glucose-6-phosphate isomerase (GPI)-induced arthritis mouse model. Imatinib or nilotinib was administered orally to the arthritic mice at different time points. Efficacy was evaluated by visual scoring and by determining the production of anti-GPI antibody. Splenocytes from the arthritic mice were cultured with GPI in the presence of imatinib or nilotinib in vitro, and cytokine levels in the culture supernatants were analyzed. To investigate the effects of imatinib and nilotinib on T-cell proliferation, lymph node cells from the arthritic mice were cultured with GPI in the presence of imatinib or nilotinib in vitro. Interleukin (IL)-17 mRNA expression in the arthritic ankle joints from the onset of arthritis was analyzed by real-time polymerase chain reaction (PCR). The administration of imatinib from day 0 showed suppression of arthritis (P < 0.05), the administration of nilotinib from day 0 resulted in pronounced suppression of arthritis (P < 0.01), and that from day 7 showed significant inhibition of the progression of arthritis (P < 0.05). A reduction in anti-GPI antibodies was correlated with the therapeutic efficacy of imatinib, but not with that of nilotinib. Imatinib dose-dependently inhibited tumor necrosis factor (TNF)-α, IL-6, interferon (IFN)-γ, and IL-17 production by splenocytes in vitro, while nilotinib inhibited only IL-17 and IFN-γ production in a dose-dependent fashion. Imatinib at 3 μM exerted a mild antiproliferative effect on CD4+ T cells (P < 0.05), whereas imatinib at 10 μM and nilotinib at 3 and 10 μM demonstrated a marked antiproliferative effect (P < 0.01). The IL17 gene expression level on day 7 tended to be higher than that on day 14. These findings suggest that imatinib and nilotinib could prevent autoimmune arthritis, essentially via distinct mechanisms, in that imatinib inhibits both inflammatory and T-cell-derived cytokine production, whereas nilotinib suppresses T-cell-derived cytokine production. Imatinib and nilotinib could have therapeutic potential for rheumatoid arthritis (RA) and other inflammatory diseases.
    No preview · Article · Dec 2010 · Modern Rheumatology
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    ABSTRACT: To compare magnetic resonance imaging (MRI) and ultrasonography (US) in the detection of joint inflammation of rheumatoid arthritis (RA), 6 patients with RA were examined by US and low-field 0.3-T nonenhanced dedicated extremity MRI (compacTscan). All patients were females, with mean age of 50.2 years, mean disease duration of 13.5 years, and mean disease activity score (DAS)28-CRP of 1.78. Each patient was treated with either infliximab, etanercept, adalimumab, or tocilizumab. Intercarpal joints, radioulnar joints, second through fifth proximal interphalangeal (PIP) joints, and first through fifth metacarpophalangeal (MCP) joints (a total of 132 joints, 22 joints in each patient) were assessed by MRI for presence of joint inflammation. A total of 156 joints (24 first interphalangeal and radiocarpal joints plus the above 132 joints), were assessed by grayscale US (GS-US) and power Doppler US (PD-US) for presence of joint inflammation by two trained ultrasonographers. We assessed correlations between joint inflammations on MRI and GS-US/PD-US, and also interobserver correlation between the two ultrasonographers by calculating intraclass correlation coefficients (ICC). Synovial hypertrophy and/or synovial fluid was detected in 74/156 joints on GS-US, and synovitis was detected in 10/156 joints on PD-US and in 38/132 joints on MRI. Using PD-US as a reference, sensitivity of MRI in detection of synovitis was 80%. Using MRI as a reference, sensitivity of PD-US was 21%. Specificity of PD-US was higher than that of MRI. Overall agreement between GS-US and MRI and between PD-US and MRI was 0.56 and 0.76, respectively, suggesting that results of PD-US are close to those of MRI. ICC was 0.545 for GS-US and 0.807 for PD-US, suggesting specificity of PD-US in detecting joint inflammation. Our results show that findings of PD-US correlated with those of MRI. Low-field MRI and PD-US are useful tools for assessment of patients with RA.
    No preview · Article · Dec 2010 · Modern Rheumatology

Publication Stats

2k Citations
406.81 Total Impact Points

Institutions

  • 2004-2014
    • University of Tsukuba
      • Institute of Clinical Medicine
      Tsukuba, Ibaraki, Japan
  • 1999-2007
    • Niigata University
      • Division of Clinical Nephrology and Rheumatology
      Niahi-niigata, Niigata, Japan
  • 2002
    • Saiseikai Niigata Second Hospital.
      Niahi-niigata, Niigata, Japan