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To evaluate the ability of geldanamycin to modulate two opposing TNFα/TNFR1-triggered signals for inflammation and cell death.The effects of geldanamycin on TNFα-induced proinflammatory cytokine production, apoptosis, NF-κB activation, caspase activation, and necroptosis in a human rheumatoid synovial cell line (MH7A) were evaluated via ELISA/qPCR, flow cytometry, dual-luciferase reporter assay, and western blotting assay, respectively. In addition, therapeutic effects on murine collagen-induced arthritis (CIA) were also evaluated.Geldanamycin disrupted RIPK1 in MH7A, thereby inhibiting TNFα-induced proinflammatory cytokine production and enhancing apoptosis. TNFα-induced NF-κB and MLKL activation was inhibited, whereas caspase 8 activation was enhanced. Recombinant RIPK1 restored the geldanamycin-mediated inhibition of TNFα-induced NF-κB activation. In addition, GM showed more clinical effectiveness than a conventional biologic TNF inhibitor, etanercept, in murine CIA and significantly attenuated synovial hyperplasia, a histopathological hallmark of RA.GM disrupts RIPK1 and selectively inhibits the TNFR1-triggered NF-κB activation signaling pathway, while enhancing the apoptosis signaling pathway upon TNFα stimulation, thereby redressing the balance between these two opposing signals in a human rheumatoid synovial cell line. Therapeutic targeting RIPK1 may be a novel concept which involves TNF inhibitor acting as a TNFR1-signal modulator and have great potential for a more fundamental, effective, and safer TNF inhibitor. Key Points • Geldanamycin (GM) disrupts RIPK1 and selectively inhibits the TNFR1-triggered NF-κB activation signaling pathway while enhancing the apoptosis signaling pathway upon TNFα stimulation, thereby redressing the balance between these two opposing signals in a human rheumatoid synovial cell line, MH7A. • GM showed more clinical effectiveness than a conventional biologic TNF-inhibitor, etanercept, in murine collagen-induced arthritis (CIA), and significantly attenuated synovial hyperplasia, a histopathological hallmark of RA. • Therapeutic targeting RIPK1 may be a novel concept which involves TNF inhibitor acting as a TNFR1-signal modulator and have great potential for a more fundamental, effective, and safer TNF-inhibitor.

Novel biomarkers of rheumatoid arthritis (RA), in addition to antibodies against cyclic citrullinated peptides, are required. Metabolome analysis is a promising approach to identify metabolite biomarkers for clinical diagnosis. We adopted a comprehensive non-targeted metabolomics approach combining capillary electrophoresis time-of-flight mass spectrometry (TOFMS) and liquid chromatography TOFMS. We constructed metabolomics profiling of 286 plasma samples of a Japanese population [92 RA patients, 13 systemic lupus erythematosus (SLE) patients and 181 healthy controls). RA case–control association tests showed that seven metabolites exhibited significantly increased levels in RA samples compared with controls (P < 1.0 × 10−4; UTP, ethanolamine phosphate, ATP, GDP, ADP, 6-aminohexanoic acid and taurine), whereas one exhibited a decreased level (xanthine). The plasma levels of these eight metabolites were not significantly different between seropositive and seronegative RA patients (P > 0.05; n = 68 and 24, respectively). The four nucleotide levels (UTP, ATP, GDP and ADP) were significantly higher in the non-treatment patients in comparison between patients with and without treatment (P < 0.014; n = 57 and 35, respectively). Furthermore, we found that none of the four nucleotide levels showed significant differences in SLE case–control association tests (P > 0.2; 13 patients with SLE and the 181 shared controls) and psoriatic arthritis (PsA) case–control association tests (P > 0.11; 42 patients with PsA and 38 healthy controls), indicating disease specificity in RA. In conclusion, our large-scale metabolome analysis demonstrated the increased plasma nucleotide levels in RA patients, which could be used as potential clinical biomarkers of RA, especially for seronegative RA., Plasma nucleotide levels are new biomarkers for RA

A 26-year-old woman with tuberous sclerosis complex (TSC) received outpatient treatment for the complication of systemic lupus erythematosus (SLE) at our hospital. She visited our hospital with a chief complaint of pitting oedema in bilateral lower legs for 3 days. The urinalysis showed massive proteinuria with a lot of white blood cell casts. The blood tests revealed hypoalbuminaemia, hypercholesterolaemia, hypocomplementaemia, and elevated anti-double-stranded DNA antibody titre. Renal biopsy was not performed because of multiple renal angiomyolipomas, which was one of the features of TSC. She was diagnosed with a nephrotic state due to lupus nephritis. Although she had a standard therapy with high-dose corticosteroid and mycophenolate mofetil and tacrolimus, complete remission had not been achieved leading to a steroid-dependent nephrotic syndrome. During the follow-up, the angiomyolipomas became larger and had a risk of rupture at the age of 29 years. Everolimus, a mechanistic target of rapamycin (mTOR) inhibitor, was started for the treatment of angiomyolipomas, and mycophenolate mofetil and tacrolimus were terminated instead. The activity of lupus nephritis was surprisingly ameliorated, and the amount of corticosteroid successfully tapered. Everolimus has been continued for 6 years without severe side effects. Accumulating evidence suggests that the activated mTOR pathway plays a key role in the pathogenesis of SLE. We reported the long-term efficacy and safety of everolimus for refractory SLE in a patient with TSC for the first time. This case suggests that everolimus can be a promising option for the treatment of lupus nephritis.

Biological disease-modifying anti-rheumatic drugs (bDMARDs) against pathogenic proinflammatory cytokines and lymphocytes, such as tumour necrosis factor-α (TNF-α), interleukin-6, T cells and B cell...

ObjectiveThe causality and pathogenic mechanism of microbiome composition remain elusive in many diseases, including autoimmune diseases such as rheumatoid arthritis (RA). This study aimed to elucidate gut microbiome’s role in RA pathology by a comprehensive metagenome-wide association study (MWAS).MethodsWe conducted MWAS of the RA gut microbiome in the Japanese population (ncase=82, ncontrol=42) by using whole-genome shotgun sequencing of high depth (average 13 Gb per sample). Our MWAS consisted of three major bioinformatic analytic pipelines (phylogenetic analysis, functional gene analysis and pathway analysis).ResultsPhylogenetic case–control association tests showed high abundance of multiple species belonging to the genus Prevotella (e.g., Prevotella denticola) in the RA case metagenome. The non-linear machine learning method efficiently deconvoluted the case–control phylogenetic discrepancy. Gene functional assessments showed that the abundance of one redox reaction-related gene (R6FCZ7) was significantly decreased in the RA metagenome compared with controls. A variety of biological pathways including those related to metabolism (e.g., fatty acid biosynthesis and glycosaminoglycan degradation) were enriched in the case–control comparison. A population-specific link between the metagenome and host genome was identified by comparing biological pathway enrichment between the RA metagenome and the RA genome-wide association study results. No apparent discrepancy in alpha or beta diversities of metagenome was found between RA cases and controls.ConclusionOur shotgun sequencing-based MWAS highlights a novel link among the gut microbiome, host genome and pathology of RA, which contributes to our understanding of the microbiome’s role in RA aetiology.

A 26-year-old woman with Takayasu's arteritis (TAK) experienced back and neck pain during tocilizumab (TCZ) treatment. The levels of C-reactive protein were normal, and ultrasonography revealed no significant changes. Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) showed signal enhancement in the walls of several arteries. Contrast computed tomography showed arterial inflammation in the same lesion. After increasing the dose of prednisolone and TCZ, all signal enhancements decreased and continued to decrease, as observed on days 76 and 132. Thus, DWIBS may be a novel imaging modality for assessing the disease activity of TAK, particularly during follow-up.

The receptor activator of nuclear factor κB ligand (RANKL) is an important factor for osteoclastogenesis and contributes to the pathology of rheumatoid arthritis (RA); thus, the anti-RANKL antibody (Ab) has been expected to protect joint destruction in RA patients. IL-8 also has osteoclastogenic activity; however, the role of IL-8 in the bone pathology of RA as well as the relation between IL-8 and RANKL remain unclear. In the present study, clinical observation revealed serum IL-8 levels of 611 pg ml−1 in RA patients with anti-RANKL Ab and 266 pg ml−1 in the same patients without anti-RANKL Ab. In vitro assay showed that anti-RANKL Ab induced production of IL-8 from pre-osteoclast-like cells (OCLs), and IL-8 promoted the formation of OCLs from peripheral monocytes even without RANKL activity. We further showed that treatment with FK506 (tacrolimus) possibly inhibits the increase in IL-8 levels in RA patients with anti-RANKL Ab, and in vitro assay confirmed that FK506 suppressed IL-8 production in pre-OCLs. These results suggest that inhibition of RANKL induces the change in osteoclastogenesis-promoting factor from RANKL to IL-8, and FK506 may be a valuable combination drug to support the use of anti-RANKL Ab in treatment of RA., A therapeutic anti-RANKL Ab increases IL-8 production in RA

MicroRNAs (miRNAs) modulate the post-transcriptional regulation of target genes and are related to biology of complex human traits, but genetic landscape of miRNAs remains largely unknown. Given the strikingly tissue-specific miRNA expression profiles, we here expand a previous method to quantitatively evaluate enrichment of genome-wide association study (GWAS) signals on miRNA–target gene networks (MIGWAS) to further estimate tissue-specific enrichment. Our approach integrates tissue-specific expression profiles of miRNAs (∼1800 miRNAs in 179 cells) with GWAS to test whether polygenic signals enrich in miRNA–target gene networks and whether they fall within specific tissues. We applied MIGWAS to 49 GWASs (nTotal = 3 520 246), and successfully identified biologically relevant tissues. Further, MIGWAS could point miRNAs as candidate biomarkers of the trait. As an illustrative example, we performed differentially expressed miRNA analysis between rheumatoid arthritis (RA) patients and healthy controls (n = 63). We identified novel biomarker miRNAs (e.g. hsa-miR-762) by integrating differentially expressed miRNAs with MIGWAS results for RA, as well as novel associated loci with significant genetic risk (rs56656810 at MIR762 at 16q11; n = 91 482, P = 3.6 × 10−8). Our result highlighted that miRNA–target gene network contributes to human disease genetics in a cell type-specific manner, which could yield an efficient screening of miRNAs as promising biomarkers.

OBJECTIVES In this study, we investigated whether monocyte CD64 (mCD64) expression is correlated with disease activity in patients with adult-onset Still disease (AOSD) and whether it could be used to distinguish between active and inactive disease states. METHODS We reviewed a series of 10 patients with a definite diagnosis of AOSD, recruited from January 2013 to December 2016. We used flow cytometry to quantitatively measure mCD64 expression levels in patients presenting with active and inactive disease states and statistically analyzed the corresponding changes. RESULTS The mean ± SD values of mCD64 expression levels in patients with active and inactive disease states were 77,148.3 ± 39,066.3 and 19,225.8 ± 7006.2 molecules/cell, respectively, indicating significantly higher mCD64 expression in the active state than in the inactive state (p = 0.005). Receiver operating characteristic analysis with a cutoff value of 31,796.0 molecules/cell was applied to distinguish active from inactive disease states; the sensitivity and specificity were both 100%. In these patients, only the mCD64 expression levels changed in parallel with disease activity under tocilizumab treatment; other conventional biomarkers measured showed no changes. CONCLUSIONS Monocyte CD64 expression could be used to clearly distinguish between active and inactive AOSD. Thus, mCD64 could be a promising biomarker for evaluating the disease activity of AOSD, even in patients receiving tocilizumab treatment.

Objectives: To assess the incidence of reactive lymph node hyperplasia (RLH) and the diagnostic characteristics that can help differentiate it from lymphoproliferative disorders (LPD) in patients w...

Background Severe infections that complicate rheumatoid arthritis may cause significant morbidity and mortality. The Modified Health Assessment Questionnaire (MHAQ) is one of the scores most used for measuring the functional status of rheumatoid arthritis (RA) patients. However, the relationship between the MHAQ score and severe infection risk has not been well studied [1]. Objectives To examine the relationship between disease-associated functional status (MHAQ) and severe infection events (SIE) in rheumatoid arthritis patients. Methods We used data from the “MiRAi” cohort in Japan. In total, 2174 RA outpatients were examined at the Osaka Minami Medical Center between January 2012 and October 2017. The risk factors were identified and evaluated by multivariate logistic regression, linearity analysis. Interactions of SIE risk between MHAQ and treatment were also observed. Results The cohort contributed to 8206 patient-years of follow-up. Overall, 251 SIEs were observed and the incidence of SIE was 3.0 infections per 100 patient-years. The mean age at first observation was 61.7 years and the mean disease duration was 10.3 years. The use of glucocorticoids (GCs), methotrexate (MTX), and biologic and targeted synthetic disease-modifying antirheumatic drugs (bDMARDs/tsDMARDs) was 59.2%, 63.8%, and 40.3%, respectively. The mean Clinical Disease Activity Index (CDAI), Simplified Disease Activity Index (SDAI), Disease Activity Scores of 28 joints (DAS28), and MHAQ at first observation were 9.76±6.39, 10.1±6.87, 2.67±0.96, and 0.43±0.58, respectively. Disease duration, the MHAQ score, and prednisolone dose (p=0.015, 0.007, and Conclusion An increased MHAQ score was lineally associated with SIE, and did not show significant interactions with bDMARD/tsDMARD use or the oral glucocorticoid dose. Therefore, the MHAQ score is considered to be a strong, independent risk factor for infection in RA patients. Reference [1] Yamanaka H, Askling J, Berglind N, Franzen S, Frisell T, Garwood C, Greenberg JD, Ho M, Holmqvist M, Novelli Horne L, et al: Infection rates in patients from five rheumatoid arthritis (R017, 3(2):e000498A) registries: contextualising an RA clinical trial programme. RMD Open 2017, 3(2):e000498. Disclosure of Interests Yuji Yoshida: None declared, Shiro Ohshima Grant/research support from: AbbVie, Eisai, Asahikasei, Speakers bureau: AbbVie, Eisai, Bristol-Meyers, Novartis, Astellas, Nippon-Kayaku, Pfizer, UCB, Ayumi, Daiichi-Sankyo, Takeda, Tanabe-Matsubishi, Chugai, Eri Oguro: None declared, Kentaro Kuzuya: None declared, Yasutaka Okita: None declared, Hidetoshi Matsuoka: None declared, Satoru Teshigawara: None declared, Maiko Yoshimura: None declared, Kentaro Isoda: None declared, Yoshinori Harada: None declared, Jun Hashimoto: None declared, Yukihiko Saeki: None declared

Background: One of the most important complications of biological disease-modifying antirheumatic drugs (bDMARDs) is severe infection, and management of patients who develop severe infection during treatment with bDMARDs is a great concern. However, no consensus exists regarding bDMARDs readministration following treatment for bDMARDs-associated infection. Objectives: We elucidated risk factors associated with severe infection recurrence in patients who developed severe infections during bDMARDs therapy. Severe infection was defined as an infection requiring hospitalization. Moreover, we analyzed whether bDMARDs readministration after severe infection in patients with rheumatoid arthritis (RA) was a risk for severe infection recurrence. Methods: The study sample comprised patients with RA who were examined and prescribed bDMARDs at Osaka Minami Medical Center between January 2010 and December 2017, as part of the MiRAi cohort. The patients who developed severe infections during bDMARDs treatment were followed-up for 12 months. Logistic regression analysis was performed using baseline disease activity, baseline treatment, and disease activity and treatment during the 12-month period. Results: Severe infections developed in 164 of a total of 1192 patients who were treated with bDMARDs during the study period, and the severe infection rate was 5.73/100 patients-years. Among the 164 patients, bDMARDs were readministered in 130 (79.3%), whereas treatment with bDMARDs was discontinued in 34 patients (20.7%). We observed 31 cases of patients with severe infections during the follow-up period (18.9/100 patients-years), of which 20 patients (15.4/100 patients-years) belonged to the bDMARDs readministration group and 11 (32.4/100 patients-years) belonged to the bDMARDs discontinuation group. The adjusted odds ratio (OR) for severe infection recurrence within 12 months in the bDMARDs readministration group was 0.39 [95% confidence interval (CI) 0.16–0.96]. At 12 months after infection, high-dose prednisolone treatment (adjusted OR 1.35, 95%CI 1.08–1.69), high C-reactive protein level (adjusted OR 1.28, 95%CI 1.02–1.62), and low serum albumin levels (adjusted OR 0.30, 95%CI 0.01–0.89) were associated with high risk of severe infection recurrence (Figure). Conclusion: Patients who developed severe infection during bDMARDs treatment were at an extremely high risk for severe infection irrespective of the readministration or discontinuation of bDMARDs after infection. Discontinuation of bDMARDs, high dose of prednisolone 12 months after infection, high levels of C-reactive protein 12 months after infection, and low levels of albumin 12 months after infection were identified as risk factors for severe infection recurrence in these patients. However, bDMARDs readministration did not increase the risk of severe infection recurrence. Reference: [1] Ramiro et al, Ann Rheum Dis 2017;76:1093-1101. Disclosure of Interests: Eri Oguro: None declared, Yuji Yoshida: None declared, Kentaro Kuzuya: None declared, Yasutaka Okita: None declared, Hidetoshi Matsuoka: None declared, Satoru Teshigawara: None declared, Maiko Yoshimura: None declared, Kentaro Isoda: None declared, Yoshinori Harada: None declared, Shiro Ohshima Grant/research support from: AbbVie, Eisai, Asahikasei, Speakers bureau: AbbVie, Eisai, Bristol-Meyers, Novartis, Astellas, Nippon-Kayaku, Pfizer, UCB, Ayumi, Daiichi-Sankyo, Takeda, Tanabe-Matsubishi, Chugai, Jun Hashimoto: None declared, Yukihiko Saeki: None declared

A 66-year-old woman with symptoms of fatigue and headache was diagnosed with giant cell arteritis (GCA). Fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) revealed the strong accumulation of FDG in the descending aorta, abdominal aorta, bilateral subclavian artery, and total iliac artery. Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) showed signal enhancement at the descending aorta and abdominal aorta. We repeated FDG-PET and DWIBS 2 months after the initiation of therapy with prednisolone. In line with the FDG-PET findings, the signal enhancement of the aortic wall completely vanished on DWIBS. DWIBS may be a novel useful tool for the diagnosis and follow-up of GCA treatment.

We report the case of a 40-year-old patient with systemic sclerosis (SSc) and systemic lupus erythematosus (SLE) overlap syndrome with pulmonary arterial hypertension (overlap-PAH) that was successfully treated with a combination of immunosuppressive therapy and the soluble guanylate cyclase stimulator riociguat. She was diagnosed with mixed connective tissue disease (MCTD) two years prior to admission. She was admitted to our hospital with dyspnea on exertion and progressive skin sclerosis. She fulfilled both SLE and SSc classification criteria and was re-diagnosed with overlap syndrome. The tricuspid valve pressure gradient (TRPG) on echocardiography was 64 mmHg at admission. On right heart catheterization, mean pulmonary arterial pressure (mPAP) was 43 mmHg and pulmonary capillary wedge pressure was 15 mmHg. We diagnosed her with SSc-SLE overlap-PAH and started treatment with corticosteroids and intravenous cyclophosphamide. We also started treatment with riociguat because we speculated she had a component of SSc-PAH and that immunosuppressive therapy alone may be insufficient. We chose riociguat because of its favorable treatment effect on SSc-PAH. Two months after treatment, her TRPG improved to 33 mmHg and the skin sclerosis improved dramatically, suggesting the efficacy of multi-drug treatment and the importance of early intervention.

Objective The intestinal microbiota is involved in the pathogenesis of arthritis. Altered microbiota composition has been demonstrated in patients with rheumatoid arthritis (RA). However, it remains unclear how dysbiosis contributes to the development of arthritis. The aim of this study was to investigate whether altered composition of human intestinal microbiota in RA patients contributes to the development of arthritis. Methods We analyzed the fecal microbiota of patients with early RA and healthy controls, using 16S ribosomal RNA−based deep sequencing. We inoculated fecal samples from RA patients and healthy controls into germ-free arthritis-prone SKG mice and evaluated the immune responses. We also analyzed whether the lymphocytes of SKG mice harboring microbiota from RA patients react with the arthritis-related autoantigen 60S ribosomal protein L23a (RPL23A). Results A subpopulation of patients with early RA harbored intestinal microbiota dominated by Prevotella copri; SKG mice harboring microbiota from RA patients had an increased number of intestinal Th17 cells and developed severe arthritis when treated with zymosan. Lymphocytes in regional lymph nodes and the colon, but not the spleen, of these mice showed enhanced interleukin-17 (IL-17) responses to RPL23A. Naive SKG mouse T cells cocultured with P copri−stimulated dendritic cells produced IL-17 in response to RPL23A and rapidly induced arthritis. Conclusion We demonstrated that dysbiosis increases sensitivity to arthritis via activation of autoreactive T cells in the intestine. Autoreactive SKG mouse T cells are activated by dysbiotic microbiota in the intestine, causing joint inflammation. Dysbiosis is an environmental factor that triggers arthritis development in genetically susceptible mice.

Objectives To examine the influence of smoking on biologics treatment against different therapeutic targets, such as TNFα, IL-6, and T cell, in rheumatoid arthritis (RA) and elucidate the underlying molecular mechanism. Methods The association between drug-discontinuation due to poor therapeutic response and smoking status was analyzed individually in biologics against different therapeutic targets by a multivariable logistic regression analysis using the “NinJa” Registry, one of the largest cohorts of Japanese RA patients. In vitro enhancement of TNFα-induced NF-κB activation and subsequent proinflammatory cytokine production by cigarette chemical components was examined by RT-PCR, qPCR, ELISA, and western blotting using an immortalized rheumatoid synovial cell line, MH7A. Results The rate of drug-discontinuation due to poor therapeutic response was higher in the current smoking group than in the never- or ever-smoking groups (the odds ratio of current/never smoking: 2.189, 95%CI; 1.305–3.672,P = 0.003; current/ever: 1.580, 95%CI; 0.879–2.839,P = 0.126) in the TNF inhibitor (TNFi) treatment group. However, this tendency was not observed in either the IL-6 or T cell inhibitor treatment groups. Cigarette smoke chemical components, such as benzo[α]pyrene, known as aryl hydrocarbon receptor (AhR) ligands, themselves activated NF-κB and induced proinflammatory cytokines, IL-1β and IL-6. Furthermore, they also significantly enhanced TNFα-induced NF-κB activation and proinflammatory cytokine production. This enhancement was dominantly inhibited by Bay 11-7082, an NF-κB inhibitor. Conclusions These results suggest a crosstalk between TNFα signaling and AhR signaling in NF-κB activation which may constitute one of the molecular mechanisms underlying the higher incidence of drug-discontinuation in RA patients undergoing TNFi treatment with smoking habits.

Background Vitamin D has been recognised not only in calcium metabolism and bone metabolism but also in the physiological activities of a wide variety of cells, and its deficiency is caused by fractures/falls, osteoporosis and other various disease risks have been reported. Objectives To clarify vitamin D satisfaction status of patients with PsA, which is one of spondyloarthritis, by measuring serum 25OHD concentration. Methods 180 patients with PsA satisfying CASPAR criteria during the visit to our hospital between August 2016 and June 2017, 125 males, averaging age 54.1 y.o., BMI average 24.2, mean disease duration of PsA and psoriasis were 8.1 years, 19.3 years, respectively. The type of psoriatic arthritis was 79 spondylitis type and 101 peripheral type. MTX was 51.7% as an agent for treating PsA, and the average dose was 8.3±3.1 mg/week. The number of biologics use was 37.2%. There were 9 cases of osteoporosis and 21 cases of osteopenia, 20 patients who were undergoing treatment for osteoporosis, and all patients were treated with activated VD3. 110 patients (61.1%) had active type VD3 paint applied to psoriasis eruption. The ACPA positive rate was 7.4%, the rheumatoid factor positive was 17.7%, and average CRP was 0.25±0.36 mg/dl. The test method for the serum 25OHD concentration was measured with the CLIA antibody method (SRL, Inc.). Regarding the judgment criteria of deficiency, although various discussions are in progress, ”the index of serum 25OHD deficiency less than 20 ng/ml” prepared by the institute of medicine (IOM) in 2011 was used. As a study item, firstly, the degree of satisfaction of vitamin D using serum 25OHD concentration was determined. Second, it divided into VD deficient group and non-deficient group age, sex, disease duration, psoriatic arthritis type, blood biochemical test, presence of active VD administration, presence or absence of active type VD coating for skin, presence or absence of MTX · BIO, Osteoporosis · Percentage of osteopenia · The presence or absence of vulnerability fracture history was compared between both groups. Results Mean serum 25OHD concentration in patients with PsA was 16.4±6.3 ng/ml and serum 25OHD deficiency was observed in 134cases (74.4%). Factors that showed significant differences between the two groups (VD deficient group/normal group) were age (54.4/59.0y.o. p=0.032), gender (female rate) 35.0%/11.9%: p=0.040, ACPA negative rate 97.0%/85.2%: p=0.010, serum MMP-3 (69.0/98.4 ng/ml p=0.030), active vitamin D top coating use rate for skin 54.0%/88.9%: p=0.001, Biologics treatment rate 49.3%/11.1%: p Conclusions 74.4% of patients with PsA had vitamin D deficiency. In the vitamin d-deficient group, low age, high female rate, ACPA negative, low serum MMP-3, VD coating low use rate for skin, biological product high usage rate were significant. Disclosure of Interest None declared

Objectives Coagulase-negative staphylococci (CoNS) is listed as the major SSI causative organism in the field of orthopaedic surgery, but detailed report on the presence or absence of methicillin-resistant CoNS of intranasal colonisation is not found. Methods In 13 months from July 2016 to the end of July 2017, 1000 cases of consecutive cases in which nasal cavity culture was performed within one month prior to hospitalisation for patients scheduled for our orthopaedic surgery. 223 men, 777 women, average age 66.4 years old, 197 cases of RA patients, 803 cases except RA patients. The method of intranasal culture is as follows. After culturing for 18 hours at 35 ° C using blood agar medium (daily water) and CHROMager MRSA selective medium (Kanto Kagaku), identification of bacterial species of the genus Staphylococcus grown and cultivation of drug susceptibility tests It was carried out by BD Phoenix according to the method of the Association (CLSI). Results The results of intranasal culture showed that S. aureus, S. epidermidis, CoNS (excluding S. Epidermidis) and culture negative were 18.2%, 27.8%, 7.8%, and 23.9%, respectively. MRSA, MRSE and MRCoNS (excluding MRSE) with methicillin resistance were 3.2%, 22.1% and 1.7%, respectively, and 27.0% of methicillin resistant bacteria were found to exist. Especially in patients with RA, the methicillin-resistant bacterial colonisation rate was significantly higher (p Conclusions Methicillin-resistant Staphylococcus was found to be 27.0% intranasal colonisation of patients in orthopaedic surgery. Especially in RA patient, it was high rate of 38.6%. In the future, we need to consider the selection of perioperative preventive antibacterial drugs. Disclosure of Interest None declared

Background We have previously reported some of the rheumatoid arthritis (RA) patients had Prevotella copri in the intestine. By using germ-free (GF) SKG mice, we also showed that Prevotella –dominated gut microbiota contribute to the development of arthritis 1) . However, P. copri itself has not been isolated from RA patients and their molecular biology was unknown. Objectives Firstly, we planned to evaluate the intestinal microbiota in RA patients before and after the treatment. Second, we isolated P. copri strains from RA patients and healthy controls (HCs) and analysed whether RA patients-derived P. copri expanded in the intestine of GF mice. Methods We first examined whether RA patients have altered composition of microbiota. All the patients were diagnosed according to the American College of Rheumatology/ European League Against Rheumatism 2010 classification criteria for RA. We collected faecal samples from 55 RA patients (61.5±9.5 years, mean ages±SD) and 33 HCs (56.2±8.2 years) to investigate the microbiota by 16S rRNA-based deep sequence technique. We also analysed bacterial counts of Prevotella and Bacteroides fragilis by qPCR method. Moreover, we isolated P. copri from faecal contents of RA patients and HCs. GF mice were inoculated with P. copri from RA patients and HCs for further analysis. Results We found that 34.5% (19/55) of RA patients and 18.1% (6/33) of healthy controls have relatively high abundance of Prevotella (>4%) in the intestine. These results were compatible with our previous observations. When we focused on the patients who harboured high abundance of Prevotella in the gut, Prevotella/B. fragilis ratio was decreased after the treatment. The mean Prevotella/B. fragilis ratio were changed from 1.28 to 0.75 (p=0.08). Further analyses revealed that RA patients-derived P. copri successfully colonised to GF-mice and induced Th17 cells in the large intestine. Conclusions We found that alternation of microbiota composition was observed after the RA treatment. Moreover, we successfully isolated P. copri from RA patients and HCs. RA patients-derived P. copri efficiently expanded in the intestine of GF mice. Reference [1] Maeda Y, et al. Dysbiosis contributes to arthritis development via activation of autoreactive T cells in the intestine. Arthritis Rheumatol2016;68(11):2646–2661. Disclosure of Interest None declared

Background Tocilizumab (TCZ), an inhibitor of interleukin-6 (IL-6), has been widely used to treat rheumatic diseases such as rheumatoid arthritis (RA) and juvenile idiopathic arthritis. Recently, TCZ was approved for use in patients with giant cell aortitis and Takayasu aortitis. However, TCZ treatment sometimes obscures changes in the conventional biomarkers for infection such as serum levels of C-reactive protein (CRP) and procalcitonin (PCT). Presepsin (P-SEP), a subtype of soluble CD14, has been recently identified as a biomarker for sepsis. In addition, we have reported the usefulness of P-SEP for the diagnosis of bacterial infection in RA patients because it is less affected by the disease activity. Objectives To examine the usefulness of P-SEP in RA patients complicated with bacterial infections during TCZ treatment. Methods In this study, 49 RA patients with bacterial infections (i+RA), 76 RA patients without bacterial infections (RA) and 23 healthy controls (HC) were enrolled. The presence of infection was strictly diagnosed by bacteriological examinations, typical clinical characteristics such as fever (38.0°C) and/or CRP elevation and/or increased white blood cell count, and improvements of these manifestations with antibiotics. Serum P-SEP levels were measured by an immunoassay. The CRP and PCT levels were measured simultaneously. Results The median serum P-SEP levels were 186.0 [interquartile range (IQR), 134.0–236.0], 691.0 [IQR, 345.5–842.0], 154.5 [IQR, 145.8–165.5] l, and 161.0 [IQR, 146.5–166.0] pg/mL for TCZ (n=25), i+TCZ (pre-antibacterial treatment; n=7), i+TCZ (post-antibacterial treatment; n=7) and the HC group, respectively. The P-SEP levels of the i+TCZ group were significantly elevated compared with those of the TCZ group (p Conclusions These results suggest that serum P-SEP levels are less affected by TCZ treatment compared with other conventional inflammatory biomarkers such as CRP and PCT. Moreover, P-SEP levels are useful for the assessment of bacterial infections in RA patients treated with TCZ. Reference [1] Tsuji S, et al. Mod Rheumatol2017;27(4):718–720. Disclosure of Interest None declared

Background and purpose Interferons (IFN), such as IFNα and IFNγ, are known to play a pivotal role for the pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE). These IFNs enhance the expression of mCD64. We recently have reported a tight correlation between mCD64 expression levels and SLE disease activity index (SLEDAI) (r=0.68, p Method mCD64 expression levels were assessed quantitatively by using flow cytometry in five patients with NPSLE. The mCD64 expression levels were compared with SLEDAI and other conventional SLE activity markers, such as anti-dsDNA antibody, complements and cerebrospinal fluid (CSF) IL-6. Result The NPSLE events included three headaches, two aseptic meningitis and one acute confusion. At the active phase of these NPSLE events, mCD64 expressions were significantly enhanced at the median of 38 541 (range 31,693–73,287) molecules/cell compared to the treated inactive phase. Additionally, mCD64 expression was significantly higher in CSF IL-6 high (more than 4.3 pg/ml) group than the low group (p=0.011). The mCD64 expression levels were significantly decreased at the inactive phase of the NPSLE after treatment (p=0.027) shown in figure 1. The changes of mCD64 expression levels correlated with SLEDAI (r=0.74, p=0.014). Conclusions mCD64 expression may be a potential biomarker for evaluating not only the disease activity but also the response of treatment in NPSLE.

Objective Semaphorin 4D (Sema4D)/CD100 has pleiotropic roles in immune activation, angiogenesis, bone metabolism, and neural development. We undertook this study to investigate the role of Sema4D in rheumatoid arthritis (RA). Methods Soluble Sema4D (sSema4D) levels in serum and synovial fluid were analyzed by enzyme-linked immunosorbent assay. Cell surface expression and transcripts of Sema4D were analyzed in peripheral blood cells from RA patients, and immunohistochemical staining of Sema4D was performed in RA synovium. Generation of sSema4D was evaluated in an ADAMTS-4–treated monocytic cell line (THP-1 cells). The efficacy of anti-Sema4D antibody was evaluated in mice with collagen-induced arthritis (CIA). Results Levels of sSema4D were elevated in both serum and synovial fluid from RA patients, and disease activity markers were correlated with serum sSema4D levels. Sema4D-expressing cells also accumulated in RA synovium. Cell surface levels of Sema4D on CD3+ and CD14+ cells from RA patients were reduced, although levels of Sema4D transcripts were unchanged. In addition, ADAMTS-4 cleaved cell surface Sema4D to generate sSema4D in THP-1 cells. Soluble Sema4D induced tumor necrosis factor α (TNFα) and interleukin-6 (IL-6) production from CD14+ monocytes. IL-6 and TNFα induced ADAMTS-4 expression in synovial cells. Treatment with an anti-Sema4D antibody suppressed arthritis and reduced proinflammatory cytokine production in CIA. Conclusion A positive feedback loop involving sSema4D/IL-6 and TNFα/ADAMTS-4 may contribute to the pathogenesis of RA. The inhibition of arthritis by anti-Sema4D antibody suggests that Sema4D represents a potential therapeutic target for RA.

To examine whether or not earlier therapeutic intervention with methotrexate (MTX) prevents the development of rheumatoid arthritis (RA) in patients with recent-onset undifferentiated arthritis (UA) showing high anti-citrullinated peptide antibody (ACPA) titers.The patients were divided into two groups, one was treated with MTX (MTX+ group, n = 29), and the other was treated without MTX (MTX- group, n = 19), and other disease-modifying anti-rheumatic drugs were not permitted in the two groups before the primary endpoint was met. The primary endpoint is the occurrence of definite RA, and it was compared in the two groups after 1 year.The percentage of patients who developed definite RA in the MTX+ group (17.2%) was significantly lower than that in the MTX- group (78.9%) (log-rank test, P0.001, n = 48); adjusted hazards ratio: 0.028 [95% confidence interval (CI): 0.003-0.250, P = 0.001, n = 39]. Treatment effectiveness was not decreased by major risk factors of RA onset such as smoking habits and human leukocyte antigen-DRB1 shared epitope (SE) (smoking habit, odds ratio [OR]: 0.041 [95% CI: 0.007-0.246] P0.001; SE, OR: 0.022 [95% CI: 0.002-0.204] P0.001). The safety issues were comparable between the two groups.This suggests that early therapeutic intervention with MTX could safely prevent the development of RA in patients with recent-onset UA showing high ACPA titers.

Background Adult-onset Still9s disease (AOSD) is a systemic inflammatory disease of unknown etiology. Overproduction of multiple inflammatory cytokines and subsequent hyperactivation of monocytes/macrophages are prominent characteristics of AOSD. However, there are no convenient and precise methods for evaluating monocyte/macrophage activation in AOSD. We previously reported that monocyte CD64 (mCD64) expression could be quantitatively measured by flow cytometry and its expression was tightly correlated with the activity of systemic lupus erythematosus. Objectives We examined the association between mCD64 expression and AOSD disease activity. Methods This was a prospective, single-center, observational study conducted between January 2013 and December 2016. Eleven active AOSD patients who fulfilled the Yamaguchi9s criteria for AOSD and had the modified Pouchot score of ≥2 were enrolled. The mCD64 expression levels were quantitatively measured by flow cytometry and individually assessed both before (Pouchot score ≥2) and after treatment (score 0). Other disease-related laboratory data, such as C-reactive protein, ferritin, and white blood cell count, were simultaneously measured. As a control, 16 active systemic lupus erythematosus (SLE) patients (SLE disease activity index ≥6), 22 active rheumatoid arthritis (RA) patients (disease activity score with 28-joint counts >3.2), and 20 healthy controls (HC) (female, 55%; mean age, 38.7±9.1 years) were enrolled. Statistical analysis was performed by the Mann-Whitney and Wilcoxon-paired tests. Results The median mCD64 expression levels were 73,339 [interquartile range (IQR), 45,861–88,181] and 16,443 (IQR, 45,891–88,181) molecules/cell before and after treatment, respectively. Thus, mCD64 expression levels were significantly decreased during the inactive phase compared with those in the active phase in AOSD (p=0.0001). The mCD64 expression levels were significantly higher in patients with active AOSD than in those with active SLE [34,648 (IQR, 44,204–24,657) molecules/cell, p=0.001], active RA [25,167 (IQR, 35,778–22,301) molecules/cell, p Conclusions These results suggest that mCD64 expression levels are highly upregulated in AOSD and tightly correlated with disease activity. The mCD64 expression level may be a useful biomarker for assessing the disease activity of AOSD. References Rau M, et al. J Rheumatol. 2010 Nov;37(11):2369–76. Kikuchi-Taura A, et al. Lupus. 2015 Sep;24(10):1076–80. Pouchot J, et al. Medicine. 1991;70:118–36. Disclosure of Interest None declared

A 72-year-old man presented with persistent oligoarthritis and positive results for rheumatoid factor and was suspected of having rheumatoid arthritis (RA). However, the musculoskeletal ultrasonography (MSUS) findings were not consistent with those of typical RA. He had undergone surgery for carpal tunnel syndrome, which allowed both histopathological and microbiological examinations to be performed. A synovial tissue culture was positive for Sporothrix schenckii, and he was diagnosed with sporotrichal tenosynovitis. He received anti-fungal therapy, and the sporotrichal tenosynovitis resolved. This case suggests that MSUS is a useful modality, and sporotrichal tenosynovitis, though rare, should be considered in the differential diagnosis of RA.

Background and aims Lupus nephritis (LN) is one of the most serious clinical manifestations of systemic lupus erythematosus (SLE). Recently, we have reported that the expression levels of CD64 on monocyte (mCD64), a high-affinity receptor for IgG (FcgRI), correlate with the disease activity of SLE (Lupus 2015;24:1076–80). However, the relation between lupus nephritis (LN) and mCD64 expression is yet to be elucidated. The aim of this study is to investigate whether or not mCD64 expression level correlates with the activity of LN. Methods We quantitatively measured the mCD64 expression levels by flow cytometry in eight SLE patients with biopsy proven LN before and after treatment. All patients fulfilled the 1997 American College of Rheumatology classification criteria for SLE. The mCD64 expression levels of the individual patients were measured both at active (presence of proteinuria >0.5 g/day and/or active urinary sediment) and inactive phase (absence of proteinuria and active urinary sediment). The changes were analysed statistically (Wilcoxon signed-rank test). Results The mean±SD of mCD64 expression levels before and after treatment were 42 463±15 466 and 19 190±1696 molecules/cell, respectively (p Conclusions The mCD64 expression level correlates with the activity of LN, although a larger scale study is needed to confirm the results.

Infection is a serious complication observed in the management of rheumatoid arthritis (RA) patients. The acute inflammatory marker C-reactive protein (CRP) is elevated both during infection and du...

Autoimmunity causes pathological conditions resulting in autoimmune diseases (ADs). Although autoimmunity is a mystery, immunological dogma suggests that autoreactive cell reactivation (ACR) breaks self-tolerance and induces autoimmunity. Thus, ACR is a royal pathway for ADs. Cumulative evidence implicates environmental factors as secondary triggers of ADs in the genetically susceptible hosts. Infection is the most likely trigger. Although several mechanisms have been proposed to explain how infectious agents trigger ADs, ACR is assumed to be an essential pathway. Here, by showing some exemplary ADs, we propose two novel pathways, “molecular modification pathway” and “hyper-immune-inflammatory response pathway”, which induce AD-like conditions directly by infectious agents without ACR. These AD-like conditions are actually not true “ADs” according to the current definition. Therefore, we define them as “pathogen-driven autoimmune-mimicry (PDAIM)”. Confirming PDAIM will open perspectives in developing novel fundamental and non-immunosuppressive therapies for ADs. The idea should also provide novel insights into both the mechanisms of autoimmunity and the pathogenesis of ADs.

Objective To evaluate the efficacious noninferiority of subcutaneous tocilizumab injection (TCZ-SC) monotherapy to intravenous TCZ infusion (TCZ-IV) monotherapy in Japanese patients with rheumatoid arthritis (RA) with an inadequate response to synthetic and/or biologic disease-modifying antirheumatic drugs (DMARDs). Methods This study had a double-blind, parallel-group, double-dummy, comparative phase III design. Patients were randomized to receive TCZ-SC 162 mg every 2 weeks or TCZ-IV 8 mg/kg every 4 weeks; no DMARDs were allowed during the study. The primary end point was to evaluate the noninferiority of TCZ-SC to TCZ-IV regarding the American College of Rheumatology criteria for 20% improvement in disease activity (ACR20) response rates at week 24 using an 18% noninferiority margin. Additional efficacy, safety, pharmacokinetic, and immunogenicity parameters were assessed. Results At week 24, ACR20 response was achieved in 79.2% (95% confidence interval [95% CI] 72.9, 85.5) of the TCZ-SC group and in 88.5% (95% CI 83.4, 93.5) of the TCZ-IV group; the weighted difference was −9.4% (95% CI −17.6, −1.2), confirming the noninferiority of TCZ-SC to TCZ-IV. Remission rates of the Disease Activity Score in 28 joints using the erythrocyte sedimentation rate and the Clinical Disease Activity Index at week 24 were 49.7% and 16.4% in the TCZ-SC group and 62.2% and 23.1% in the TCZ-IV group, respectively. Serum trough TCZ concentrations were similar between the groups over time. Incidences of all adverse events and serious adverse events were 89.0% and 7.5% in the TCZ-SC group and 90.8% and 5.8% in the TCZ-IV group, respectively. Anti-TCZ antibodies were detected in 3.5% of the TCZ-SC group; no serious hypersensitivity was reported in these patients. Conclusion TCZ-SC monotherapy demonstrated comparable efficacy and safety to TCZ-IV monotherapy. TCZ-SC could provide additional treatment options for patients with RA.

To evaluate the safety and efficacy of retreatment with tocilizumab (TCZ) in patients who had participated in the DREAM study (Drug free remission/low disease activity after cessation of tocilizumab [Actemar] monotherapy study) and had experienced loss of efficacy.Patients were retreated with TCZ or other disease modifying antirheumatic drugs (DMARDs). Disease activity was measured using the 28-joint disease activity score (DAS28) for 12 weeks.A total of 164 eligible patients, including 161 who experienced loss of efficacy within 52 weeks of the DREAM study, resumed treatment: 157 with TCZ and 7 with DMARDs and/or infliximab. Of TCZ-treated patients, 88.5 % (139 patients) achieved DAS282.6 within 12 weeks, whereas among patients treated with DMARDs and/or infliximab only 14.3 % (1 patient) achieved DAS282.6. Adverse events were observed in 70 TCZ-treated patients (44.0 %), but no serious infusion reactions were observed.Retreatment with TCZ was well-tolerated and effective in patients who had responded to the preceding TCZ monotherapy but had experienced loss of efficacy after cessation of TCZ.

Objectives: This study aimed to evaluate the safety of CT-P13 in patients with rheumatoid arthritis (RA) during long-term treatment or after switching from innovator infliximab (IFX). Methods: Patients who completed 54 weeks of treatment in a phase I/II study (PI/II) received CT-P13 at an initial dose of 3 mg/kg at Week 62, with dose increases permitted up to 10 mg/kg. The primary endpoint was adverse event (AE) incidence. Results: Thirty-four of 38 patients in the maintenance group and 29 of 33 in the switch group reported at least one AE. Safety profiles in both groups were similar to those in PI/II. Eleven of 28 patients who were positive for anti-drug antibodies (ADA) at Week 62 discontinued the study before Week 110. Forty-one of 43 ADA-negative patients remained negative, and 10 of 28 ADA-positive patients became negative during the study. The mean DAS28 (ESR) at Week 134 was 3.166 in the maintenance group and 3.955 in the switch group. Conclusions: CT-P13 was well tolerated in patients who maintained the treatment after 54 weeks and in patients who switched to CT-P13 after 54 weeks of IFX treatment. The study also demonstrated a stable clinical efficacy of CT-P13 in RA patients.

In this review, recent changes in both treatments and outcomes of rheumatoid arthritis (RA) in Japan were analyzed by viewing the National Database of Rheumatic Diseases by iR-net, one of the largest clinical databases for RA patients in Japan. Regarding drug therapy, the use of methotrexate has been continuously increasing and has established a place as an anchor drug in the treatment of RA among other nonbiologic disease-modifying antirheumatic drugs; however, the dosage used is still significantly less compared with that of western countries. In addition to methotrexate, the use of tacrolimus has increased gradually. The most prominent observed change is a rapid increase in the use of biologics, which rose to stardom in the treatment of RA in Japan and western countries. These changes in drug therapy could allow us to control RA disease activity more tightly. In line with this, the outcomes of patients with RA in Japan have been improving continuously, both clinically and functionally. Subsequently, the use of both NSAIDs and corticosteroids has decreased. In addition, overall rates of joint operations related to RA have also decreased; in particular, a significant decrease was noticed in the incidence of joint replacement and synovectomy. Overall, the trends in treatments and subsequent outcomes for RA in Japan have exactly followed those seen in western countries.

A prospective study was made to seek for a convenient biomarker to predict progression of bone destruction (PBD) in early stages of rheumatoid arthritis (ERA). All participated patients had definite RA and their radiographic stages were mild less than stage II of the Steinbrocker classification, naïve for treatment of any DMARDs or corticosteroids. After the entry, they were treated according to the 2002 ACR management guideline for RA. The candidate biomarkers (RF-IgM, RF-IgG, CARF, ACPA, CRP, ESR, NTx, MMP-3, IL-6 and osteopontin) were measured at the entry. PBD was assessed radiographically by interval changes in the modified Sharp scores (ΔSHS) for 24 months. The associations between ΔSHS and baseline biomarkers were assessed statistically by multivariate regression analyses. Both the baseline ACPA and IL-6 levels correlated with PBD, suggesting that they could predict PBD in ERA.

This article concerns a male patient with Mikulicz's disease (MD) accompanied with marked elevation of serum immunoglobulin (Ig)G4 and IgE levels. His peripheral blood mononuclear cells (PBMC) showed markedly enhanced in vitro production of interleukin (IL)-4, IL-5, IL-13, but not interferon gamma (IFN-gamma) compared with patients with Sjögren's syndrome (SS) and healthy donors, suggesting distinct Th2 bias in this MD patient. Besides the prominent infiltration of IgG4-producing plasma cells, the enhanced expression of both CD40 and CD40 ligand (CD40L) were observed in the swollen salivary gland of the MD patient, suggesting enhanced signaling pathways for the induction of IgG4 and IgE switching. Possible differences between MD and SS in light of their underlying pathogenesis are discussed.

The purpose of this study was to describe the prevalence of total joint arthroplasty (TJA) in Japanese rheumatoid arthritis (RA) patients undergoing conventional drug treatment in a large observational cohort in Japan. A total of 5,177 RA patients were studied for the prevalence of TJA, who were enrolled in the NinJa database during the fiscal year of 2006. The cases of 2,695 RA patients with more than ten years of disease duration were extracted and subjected to further analysis. The prevalence of TJA increased in accordance with the disease duration, and the prevalence was markedly increased after ten years. Among the 2,695 patients with more than ten years of disease duration, 1,431 TJAs were performed in 645 (24.6%) patients. The patients with TJA had higher disease activity than those without TJA. In this cross-sectional study, TJAs were performed in approximately a quarter of the Japanese RA patients with more than ten years of disease duration. The result showed that patients with higher disease activity required TJA.

Osteoclasts are the only somatic cells with bone-resorbing capacity and, as such, they have a critical role not only in normal bone homeostasis (called 'bone remodelling') but also in the pathogenesis of bone destructive disorders such as rheumatoid arthritis and osteoporosis. A major focus of research in the field has been on gene regulation by osteoclastogenic cytokines such as receptor activator of NF-kappaB-ligand (RANKL, also known as TNFSF11) and TNF-alpha, both of which have been well documented to contribute to osteoclast terminal differentiation. A crucial process that has been less well studied is the trafficking of osteoclast precursors to and from the bone surface, where they undergo cell fusion to form the fully differentiated multinucleated cells that mediate bone resorption. Here we report that sphingosine-1-phosphate (S1P), a lipid mediator enriched in blood, induces chemotaxis and regulates the migration of osteoclast precursors not only in culture but also in vivo, contributing to the dynamic control of bone mineral homeostasis. Cells with the properties of osteoclast precursors express functional S1P(1) receptors and exhibit positive chemotaxis along an S1P gradient in vitro. Intravital two-photon imaging of bone tissues showed that a potent S1P(1) agonist, SEW2871, stimulated motility of osteoclast precursor-containing monocytoid populations in vivo. Osteoclast/monocyte (CD11b, also known as ITGAM) lineage-specific conditional S1P(1) knockout mice showed osteoporotic changes due to increased osteoclast attachment to the bone surface. Furthermore, treatment with the S1P(1) agonist FTY720 relieved ovariectomy-induced osteoporosis in mice by reducing the number of mature osteoclasts attached to the bone surface. Together, these data provide evidence that S1P controls the migratory behaviour of osteoclast precursors, dynamically regulating bone mineral homeostasis, and identifies a critical control point in osteoclastogenesis that may have potential as a therapeutic target.

We report a case of Wegener’s granulomatosis (WG) with central nervous system (CNS) involvement in a woman who complained of bilateral visual disturbance. The intracranial necrotizing granulomatous lesion was confirmed by MR imaging and brain biopsy. After high-dose oral corticosteroid treatment, not only clinical manifestations but also laboratory tests improved. Moreover, the CNS lesion completely regressed. This suggests that high-dose corticosteroid alone might be effective in treating WG with CNS involvement.

Among the 5,043 consecutive patients registered in the postmarketing surveillance for leflunomide, 61 were reported to have lung injury and 24 died from it. The adjusted multivariate logistic regression analysis of the risk factors showed that preexisting interstitial lung disease posed the greatest risk, as well as loading dose, smoking history, and low body weight of 40 kg or less with odds ratios of 8.17, 3.97, 3.12, and 2.91, respectively. In 12 patients, lung injury developed even 2 months after leflunomide withdrawal. When patients with (n = 9) and without (n = 13) fatal outcome were compared, eight out of the former, and six out of the latter had preexisting interstitial lung disease; the former showed severe hypoxemia, high serum C-reactive protein level, hypoalbuminemia, and continuous lymphocytopenia, and required mechanical ventilation. On the basis of these results and literature review, the committee proposes that leflunomide should only be recommended as a second-line drug, should not be administered to patients with preexisting interstitial lung disease, should also not be administered to patients with smoking history or those with low body weight, and should be administered without loading dose. Careful monitoring is necessary, and when lung injury develops, leflunomide elimination using colestyramine is mandatory.

An important process in kidney stone formation is the conversion of retentive crystals in renal tubules to concrete stones. Osteopontin (OPN) is the major component of the kidney calcium-containing stone matrix. In this study, we estimated OPN function in early morphological changes of calcium oxalate crystals using OPN knockout mice: 100 mg/kg glyoxylate was intra-abdominally injected into wildtype mice (WT) and OPN knockout mice (KO) for a week, and 24-h urine oxalate excretion showed no significant difference between WT and KO. Kidney crystal depositions were clearly detected by Pizzolato staining but not by von Kossa staining in both genotypes, and the number of crystals in KO was significantly fewer than in WT. Morphological observation by polarized light optical microphotography and scanning electron microphotography (SEM) showed large flower-shaped crystals growing in renal tubules in WT and small and uniform crystals in KO. X-ray diffraction detected the crystal components as calcium oxalate monohydrate in both genotypes. Immunohistochemical staining of OPN showed that the WT crystals contained OPN protein but not KO crystals. We concluded that OPN plays a crucial role in the morphological conversion of calcium oxalate crystals to stones in mouse kidneys.

Osteoclasts are bone-resorbing multinuclear polykaryon that are essential for bone remodeling and are formed through cell fusion of mononuclear macrophage/monocyte-lineage hematopoietic precursors. In arthritic joints, a large number of activated osteoclasts can be detected, which are suggested to be causative of bone erosion in rheumatoid arthritis. It has been fully established that osteoclastogenesis is critically regulated by several key essential factors, such as M-CSF and RANKL. However, regarding their most characteristic property, i.e., cell fusion to form giant polykaryons, there are still miscellaneous questions to be clarified, although several molecules have been shown to be critically involved in this process. Here we review the latest knowledge about osteoclastogenic cell fusion and novel concepts underlying the characteristic phenomenon. Because cell fusion is a genuine property of mature osteoclasts, modulating this process will become a promising therapeutic tool for bone resorptive disorders in the future.

We showed that RGS18, a myeloid lineage-specific RGS protein that is inhibited after activation of the RANK/RANKL system, is a negative regulator of osteoclastogenesis. RGS18 acts through an external acidosis-sensing osteoclastogenic mechanism through the OGR1/NFAT pathway. Introduction: Osteoclasts are bone-resorbing multinuclear giant cells that are differentiated from mononuclear macrophage/monocyte lineage precursors stimulated by the RANK/RANKL system. The regulators of G-protein signaling (RGS) family is a diverse group of proteins that accelerate intrinsic GTP hydrolysis on heterotrimeric G-protein α subunits and play crucial roles in physiological regulation of G-protein –mediated cell signaling in various tissues and organs. We examined the expression and function of RGS18, a myeloid lineage-specific RGS protein, during osteoclastogenesis. Materials and Methods: A macrophage/monocyte lineage cell line, RAW264.7, and primary osteoclast precursor monocytes derived from mouse bone marrow cultured with macrophage-colony stimulating factor (M-CSF ) (bone marrow–derived monocytes [BMMs]) were used in this study. Both cell types differentiate into osteoclast-like cells on activation by RANKL. Expression of different RGS proteins, including RGS18, was assessed by gene-specific RT-PCR. The subcellular distribution of RGS18 on native osteoclasts in bone tissues, as well as in RAW264.7 cells, was examined by immunohistochemistry using a specific polyclonal antibody. Short interfering RNA against RGS18 was used to inhibit the function endogenous RGS18 in these cell types. Activation of NFATc1, an osteoclastogenic transcription factor, on external acidosis was assessed by visualizing the nuclear localization of NFATc1 visualized with anti-NFATc 1 antibody. Results: RAW264.7 and BMM cells both expressed mRNA for 10 different mammalian RGS proteins, including RGS18. Expression of RGS18 is significantly inhibited by RANKL both cell types, and inhibition of RGS18 function using RNA interference prominently enhanced osteoclastogenesis on stimulation with RANKL. The effect of RGS18 inhibition was reversed by blocking of proton-sensing OGR1 signaling, and overexpression of exogenous RGS18 inhibited extracellular acidosis-mediated NFATc1 activation. Immunohistochemical studies of mouse bone tissues revealed expression of RGS18 in osteoclasts in vivo. Conclusions: RGS18 acts as a negative regulator of the acidosis-induced osteoclastogenic OGR1/NFAT signaling pathway, and RANKL stimulates osteoclastogenesis by inhibiting expression of RGS18. Therefore, the results suggest a novel control mechanism of osteoclastogenesis by RGS proteins.

We evaluated the diagnostic value of anti-cyclic citrullinated peptide 2 (anti-CCP2) antibodies and other potential diagnostic biomarkers (IgM rheumatoid factor, anti-agalactosyl IgG antibodies, matrix metalloproteinase 3, C-reactive protein) for predicting early development of rheumatoid arthritis (RA). Patients were defined as having recent-onset undifferentiated arthritis (UA) if they had developed arthritis in two or more joints within the previous 2 years and could not be classified with a well-defined arthropathy. Baseline levels of biomarkers were measured in blood samples collected at the entry of the study and the patients were followed for 1 year to monitor development of RA. Diagnoses of RA and non-RA arthropathies were made according to individual standard diagnostic criteria. A total of 146 patients were enrolled in the study. In the follow-up year, 18 patients developed RA, 54 developed non-RA arthropathies, and 60 remained in the UA category. The sensitivity and specificity of the presence of anti-CCP2 antibodies for the diagnosis of RA were 83.3 and 93.0%, respectively. The positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of anti-CCP2 antibodies for RA (65.2, 97.2, and 91.7%, respectively) were higher than for any other biomarker. Combination of anti-CCP2 with any other biomarker only slightly improved each diagnostic value compared to the presence of anti-CCP2 alone. Among the anti-CCP2-positive patients, the average titer was significantly higher in those with RA than in non-RA or UA patients (163.7 +/- 138.4 vs 55.2 +/- 72.0 U/ml, p = 0.017). Anti-CCP2 antibodies are superior to any other single biomarker for predicting early development of RA in patients with recent-onset UA and the diagnostic value of anti-CCP2 alone is similar to that for biomarker combinations. Moreover, the anti-CCP2 antibody titer is useful to discriminate between patients at high risk for early developing RA from those at risk of developing non-RA arthropathies.

Background Osteoclasts are bone-resorbing multinuclear polykaryons essential for bone remodeling, formed through cell fusion of mononuclear macrophage/monocyte lineage precursor cells upon stimulation by the RANK/RANKL system. Recent studies have revealed that a family of tetraspanin proteins, such as CD9, is critically involved in the cell fusion/polykaryon formation of these cell types. Until now, however, there is limited knowledge about the types of tetraspanins expressed in osteoclasts and their precursors. Methods The expression of different tetraspanin proteins in a monocyte/macrophage-lineage osteoclast precursor cell line, RAW264.7, was cyclopedically investigated using RT-PCR with specific primers and quantitative real-time RT-PCR. The function of two kinds of tetraspanins, Tspan-5 and NET-6, whose expression pattern was altered by RANKL stimulation, was examined by transfecting gene-specific short-interfering RNAs into these cell types. Results Of the 17 tetraspanins in mammalian hematopoietic cells, RAW264.7 cells express mRNA for 12 different kinds of tetraspanins, namely, CD9, CD37, CD53, CD63, CD81, CD82, CD151, NAG-2, NET-6, SAS, Tspan-3, and Tspan-5. Interestingly, during their maturation into osteoclasts upon RANKL stimulation, the transcript for Tspan-5 is up-regulated, whereas that for NET-6 is down-regulated. Targeted inhibition of Tspan-5 by using gene-specific RNA interference suppressed RANKL-induced cell fusion during osteoclastogenesis, whereas inhibition of NET-6 augmented the osteoclastogenesis itself. These results suggest that Tspan-5 and NET-6 have a reciprocal function during osteoclastogenesis, i.e., positive and negative regulation by Tspan-5 and NET-6, respectively. RANKL regulates osteoclastogenesis by altering the balances of these tetraspanin proteins. Conclusions These data indicate that a diversity of tetraspanins is expressed in osteoclast precursors, and that cell fusion during osteoclastogenesis is regulated by cooperation of distinct tetraspanin family proteins such as Tspan-5 and NET-6. This study indicates that functional alterations of tetraspanin family proteins may have therapeutic potential in diseases where osteoclasts play a major role, such as rheumatoid arthritis and osteoporosis.

Background Hemophagocytic lymphohistiocytosis associated with autoimmune diseases is seen in patients with systemic juvenile idiopathic arthritis, adult-onset Still’s disease, and systemic lupus erythematosus, whereas it is rarely seen in patients with dermatomyositis. In addition, central nervous system involvement with dermatomyositis is rare. To the best of our knowledge, this is the first case of hemophagocytic lymphohistiocytosis complicated by leukoencephalopathy in a patient with dermatomyositis accompanied with peripheral T-cell lymphoma. Case presentation A 17-year-old Asian male adolescent with dermatomyositis and hemophagocytic lymphohistiocytosis that were controlled with corticosteroid therapy presented to our hospital with high fever and altered consciousness. Brain magnetic resonance imaging revealed multiple cerebral lesions. We diagnosed the central nervous system lesions as leukoencephalopathy secondary to dermatomyositis and hemophagocytic lymphohistiocytosis. Because corticosteroid and cyclophosphamide pulse therapy was ineffective, he was treated with a modified hemophagocytic lymphohistiocytosis-2004 protocol, which resulted in the disappearance of the lesions of his central nervous system. Conclusions Our findings suggest that the hemophagocytic lymphohistiocytosis-2004 protocol including etoposide should be initiated immediately in patients with hemophagocytic lymphohistiocytosis who respond poorly to treatment for the underlying disease. Moreover, irrespective of the underlying disease, patients with hemophagocytic lymphohistiocytosis with central nervous system lesions might require bone marrow transplantation.