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Objective B-cell activating factor (BAFF) is implicated in SLE pathogenesis. Blocking BAFF signalling has contributed to reducing glucocorticoid dosage and preventing organ damage. However, clinical characteristics of patients who may benefit from this therapy are not yet fully elucidated. Therefore, we identified patients with high BAFF-bioactivity to investigate their clinical characteristics and BAFF-producing cells. Methods We established the reporter cell for BAFF and investigated the clinical characteristics of SLE patients with high BAFF-bioactivity. We identified BAFF-expressing kidney cells using publicly available scRNA-seq data and immunohistological analysis. SLE patients were stratified based on the bioactivity of BAFF and type-I IFN (IFN-I) to identify associated characteristic clinical manifestations. Results SLE patients, especially patients with LN, had significantly higher serum BAFF-bioactivity than healthy controls (HC) and non-LN patients. Additionally, single-cell-RNA-seq data and immunohistological analysis of kidney samples from LN patients revealed that BAFF is expressed in glomerular macrophages and mesangial cells. Notably, BAFF bioactivity was elevated in the urine of LN patients compared with that of non-LN patients, while no IFN-I bioactivity was detected in the urine. Furthermore, SLE stratification based on bioactivities of serum BAFF and IFN-I revealed the clinical characteristics of patients: high BAFF represented patients with LN and high IFN-I represented patients with blood and skin manifestations. Conclusions Monitoring urinary BAFF-bioactivity may be valuable in diagnosing LN. Furthermore, stratification based on serum BAFF and IFN-I bioactivities may allow the identification of appropriate patients for biologics targeting BAFF and IFN-I.

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease, and many peripheral immune cell populations (ICPs) are thought to be altered according to the course of the disease. However, it is unclear which ICPs are associated with the clinical phenotypes of SLE. We analyzed peripheral blood mononuclear cells (PBMCs) of 28 SLE patients using mass cytometry and identified 30 ICPs. We determined the proliferative activity of ICPs by measuring the proportion of cells expressing specific markers and Ki-67 among CD45+ cells (Ki-67+ proportion). We observed an increased Ki-67+ proportion for many ICPs of SLE patients and examined the association between their Ki-67+ proportions and clinical findings. The Ki-67+ proportions of five ICPs [classical monocyte (cMo), effector memory CD8+ T cell (CD8Tem), CXCR5− naive B cell (CXCR5− nB), and CXCR5− IgD−CD27− B cell (CXCR5− DNB)] were identified as clinically important factors. The SLE Disease Activity Index (SLEDAI) was positively correlated with cMo and plasma cells (PC). The titer of anti-DNA antibodies was positively correlated with cMo, CXCR5− nB, and CXCR5− DNB. The C4 level was negatively correlated with CXCR5− DNB. The bioactivity of type I interferon was also positively correlated with these ICPs. Fever and renal involvement were associated with cMo. Rash was associated with CD8Tem and CXCR5− DNB. On the basis of the proliferative activity among five ICPs, SLE patients can be classified into five clusters showing different SLE phenotypes. Evaluation of the proliferative activity in each ICP can be linked to the clinical phenotypes of individual SLE patients and help in the treatment strategy.

We conducted a Japanese GWAS for systemic sclerosis (SSc) comprising 1,428 cases and 112,599 controls, the largest Asian GWAS for SSc ever, and identified three novel signals. The lead SNP in FCGR/FCRL region had a strong effect size (OR 2.05, P = 4.9×10−11). The complete LD SNP, rs10917688, was found in a cis-regulatory element and a part of binding motifs for IRF8. IRF8 was a significant locus in the European GWAS and rs10917688 showed an association only in the presence of the risk allele of IRF8 in Japanese. rs10917688 was marked with H3K4me1 in primary B cells, and the heritability was enriched in active histone marks of primary B cells. A meta-analysis with the latest European GWAS found additional 30 significant loci including three novel signals. PRS constructed with the effect sizes of the meta-analysis indicated potential portability of genetic associations beyond populations (AUC: 0.593). The fitting of PRS was improved by further prioritizing the top 5% SNPs of IRF8 biding sites in B cells, underscoring common genetic architecture across populations and critical roles of B cells and IRF8 for SSc development.

ObjectivesRaynaud’s phenomenon (RP) is a peripheral vascular disorder that frequently occurs in systemic sclerosis (SSc). Although therapeutic heating seems reasonable given that RP is elicited by cold stimuli, the effects of heating are still unclear. We examined the effects of heating applied on various body parts in SSc patients with RP of fingers.MethodsFourteen SSc patients heated their neck, elbows, and wrists with disposable heating pads for 1 week each. The visual analogue scale (VAS) for RP during each heating period was compared with that of each 1-week pre-treatment interval. On the day after the expiration of each heating period, their finger temperature, the finger blood flow, and angiogenesis-related factors (vascular endothelial growth factor, endostatin, angiopoietin-1, and angiopoietin-2) obtained from the cubital vein and fingertip were measured.ResultsThe mean VAS was significantly reduced during the heating of the neck and elbows. Fingertip blood samples showed significantly increased angiopoietin-1 after each of the heating periods and increased endostatin after wrist heating. After the termination of heating, changes in finger temperature or blood flow could not be detected.ConclusionsHeating the neck or elbows can alleviate RP in SSc. The heat up-regulates angiopoietin-1 in the fingers.

Autoimmune inflammatory rheumatic disease (AIRD) patients are at high risk of the coronavirus disease 2019 (COVID-19), but the medium-term effects of immunosuppressants on vaccine efficacy are unknown. We investigated the duration of humoral responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) wild-type and Omicron variant in AIRD patients administered with two doses of the BNT162b2 (Pfizer-BioNTech) vaccine.Serum-neutralizing antibody (NAb) and anti-receptor-binding domain (RBD)/spike antibody levels were measured. Short- and medium-term effects of immunosuppressants were analyzed pre-vaccination (Term 1) and 14-42 days (Term 2) and 100-200 days (Term 3) after the second vaccination.From Feb 1, 2021, to Feb 28, 2022, 439 AIRD patients and 146 healthy controls were investigated. The seropositivity rate and logGlucocorticoids, TNFis, and abatacept treatments negatively affect the longevity of humoral responses to SARS-CoV-2, including Omicron, after two vaccine doses. These findings may inform the timing of additional vaccination for AIRD patients.Cloud Funding of Peace Winds Japan; Center of Innovation Program from the Ministry of Education, Culture, Sports, Science and Technology of Japan; Japan Society for the Promotion of Science KAKENHI; Japan Agency for Medical Research and Development; Kansai Economic Federation; Mitsubishi Zaidan; and Research Grant from Japan Agency for Medical Research and Development-Core Research for Evolutional Science and Technology.

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

TAFRO syndrome is a newly proposed disease that is characterised by thrombocytopenia, anasarca, fever, reticulin fibrosis (or renal dysfunction), and organomegaly. Generally, high doses of corticosteroids are recommended for the initial treatment of TAFRO syndrome; however, some patients experience prolonged refractory thrombocytopenia after initiating such therapies. If corticosteroid treatment alone is ineffective, additional immunosuppressive therapies such as cyclosporine A are recommended. Since long-term use of immunosuppressive therapies with TAFRO syndrome sometimes causes serious infection, it is important to recognise the time to recovery from thrombocytopenia. In this study, we investigated how long it took to recover from thrombocytopenia, to aid clinicians in decision-making regarding the need to strengthen treatment for prolonged thrombocytopenia. Here, we describe three of our patients with TAFRO syndrome exhibiting prolonged thrombocytopenia. We also investigated the median period to recovery from this complication (defined as the time to increase the platelet count above 50,000/µL) after the initiation of high-dose corticosteroid treatment in our 3 cases and 38 peer-reviewed cases. We found that it took our patients 61 days to recover from thrombocytopenia; in comparison, our investigation of the 38 peer-reviewed case reports revealed a median recovery time of 47.5 days among previously reported patients. We showed the time to recovery from thrombocytopenia in patients with TAFRO syndrome for the first time. Our findings ought to be useful for decision-making among clinicians regarding the administration of other immunosuppressive treatments in addition to corticosteroid.

ObjectiveDespite the importance of type I interferon (IFN-I) in systemic lupus erythematosus (SLE) pathogenesis, the mechanisms of IFN-I production have not been fully elucidated. Recognition of nucleic acids by DNA sensors induces IFN-I and interferon-stimulated genes (ISGs), but the involvement of cyclic guanosine monophosphate (GMP)–AMP synthase (cGAS) and stimulator of interferon genes (STING) in SLE remains unclear. We studied the role of the cGAS–STING pathway in the IFN-I-producing cascade driven by SLE serum.MethodsWe collected sera from patients with SLE (n=64), patients with other autoimmune diseases (n=31) and healthy controls (n=35), and assayed them using a cell-based reporter system that enables highly sensitive detection of IFN-I and ISG-inducing activity. We used Toll-like receptor-specific reporter cells and reporter cells harbouring knockouts of cGAS, STING and IFNAR2 to evaluate signalling pathway-dependent ISG induction.ResultsIFN-I bioactivity and ISG-inducing activities of serum were higher in patients with SLE than in patients with other autoimmune diseases or healthy controls. ISG-inducing activity of SLE sera was significantly reduced in STING-knockout reporter cells, and STING-dependent ISG-inducing activity correlated with disease activity. Double-stranded DNA levels were elevated in SLE. Apoptosis-derived membrane vesicles (AdMVs) from SLE sera had high ISG-inducing activity, which was diminished in cGAS-knockout or STING-knockout reporter cells.ConclusionsAdMVs in SLE serum induce IFN-I production through activation of the cGAS–STING pathway. Thus, blockade of the cGAS–STING axis represents a promising therapeutic target for SLE. Moreover, our cell-based reporter system may be useful for stratifying patients with SLE with high ISG-inducing activity.

ObjectivesInappropriate activation of neutrophils plays a pathological role in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). The aim of this study was to investigate the functions of semaphorin 4D (SEMA4D) in regulation of neutrophil activation, and its involvement in AAV pathogenesis.MethodsSerum levels of soluble SEMA4D were evaluated by ELISA. Blood cell-surface expression of membrane SEMA4D was evaluated by flow cytometry. To determine the functional interactions between neutrophil membrane SEMA4D and endothelial plexin B2, wild-type and SEMA4D−/− mice neutrophils were cultured with an endothelial cell line (MS1) stained with SYTOX green, and subjected to neutrophil extracellular trap (NET) formation assays. The efficacy of treating human neutrophils with recombinant plexin B2 was assessed by measuring the kinetic oxidative burst and NET formation assays.ResultsSerum levels of soluble SEMA4D were elevated in patients with AAV and correlated with disease activity scores. Cell-surface expression of SEMA4D was downregulated in neutrophils from patients with AAV, a consequence of proteolytic cleavage of membrane SEMA4D. Soluble SEMA4D exerted pro-inflammatory effects on endothelial cells. Membranous SEMA4D on neutrophils bound to plexin B2 on endothelial cells, and this interaction decreased NET formation. Recombinant plexin B2 suppressed neutrophil Rac1 activation through SEMA4D’s intracellular domain, and inhibited pathogen-induced or ANCA-induced oxidative burst and NET formation.ConclusionsNeutrophil surface SEMA4D functions as a negative regulator of neutrophil activation. Proteolytic cleavage of SEMA4D as observed in patients with AAV may amplify neutrophil-mediated inflammatory responses. SEMA4D is a promising biomarker and potential therapeutic target for AAV.

A contribution of epigenetic modifications to B cell tolerance has been proposed but not directly tested. Here we report that deficiency of ten-eleven translocation (Tet) DNA demethylase family members Tet2 and Tet3 in B cells led to hyperactivation of B and T cells, autoantibody production and lupus-like disease in mice. Mechanistically, in the absence of Tet2 and Tet3, downregulation of CD86, which normally occurs following chronic exposure of self-reactive B cells to self-antigen, did not take place. The importance of dysregulated CD86 expression in Tet2- and Tet3-deficient B cells was further demonstrated by the restriction, albeit not complete, on aberrant T and B cell activation following anti-CD86 blockade. Tet2- and Tet3-deficient B cells had decreased accumulation of histone deacetylase 1 (HDAC1) and HDAC2 at the Cd86 locus. Thus, our findings suggest that Tet2- and Tet3-mediated chromatin modification participates in repression of CD86 on chronically stimulated self-reactive B cells, which contributes, at least in part, to preventing autoimmunity.

Background:For patients with connective tissue diseases (CTD), vasodilators are used to treat Raynaud’s phenomenon (RP), they are difficult to control only by medication. Although physicians recommend the use of a portable handwarmer or gloves to patients with CTD presenting with RP, sustained heat-retention effects cannot be obtained from them because the patients’ daily life-related activities prevent their continued use. Since the wrist mounted disposable heat pad maintains the degrees of freedom of the hands and fingers and can remain usable during the daily activities, we considered this heat pad as a useful and highly practical heating method for CTD patients presenting with RP.Objectives:To investigate the usability and changes in symptoms resulting from the use of the wrist mounted disposable heat pad in CTD patients presenting with RP.Methods:Subjects were 23 outpatients with CTD presenting with RP (23 females; mean age 62.6 years; mean duration following the onset of RP 10.3 years; 12 systemic sclerosis, 5 mixed connective tissue disease, 5 Sjögren’s syndrome, and 1 systemic lupus erythematosus) who had used the wrist mounted disposable heat pad (put the pad in a specifically designed holder and wrap it around wrist joint (max. temperature 42 degrees Celsius, heat-retention time 6 hours)). We investigated through interviews with them the use situations, usability, and changes in RP. During their using the heat pad, medication and daily life-related precautions against RP continued to be implemented as before.Results:Many patients had no knowledge of the heat pad (n=17, 73.9%). The most common wearing time of the heat pad was 5–6 hours (n=8, 34.8%). As for scenes of wearing the heat pad, patients who wore the pad when being out of the home accounted for the highest proportion (n=16, 69.6%), and as follows: at home (n=6, 26.1%), during kitchen work (n=3, 13.0%), and during housework (n=2, 8.7%). 17 patients (73.9%) replied that usability was “good”, and 18 (78.3%) replied that usability was “better” compared with conventional measures. Moreover, many patients (n=16, 69.6%) replied that RP and associated symptoms had become reduced or alleviated. No patients replied that RP and associated symptoms had become exacerbated or severer. In terms of advantages of using the heat pad, patients who replied that the site on which the pad was mounted was felt to be warm accounted for the highest proportion (n=8, 34.8%), and those who replied that sites other than where the pad was mounted (such as fingertips, hands, and arms) were also warmed accounted for virtually the same proportion (n=7, 30.4%). Over 60% of the patients (n=14, 60.9%) replied that symptoms associated with RP (skin color, cold sensation, and pain) had become reduced or disappeared. In terms of disadvantages of using the heat pad, patients who replied that it was bothersome to use the pad accounted for the highest proportion while other patients made replies referring to cost and bad appearance. No significant accident occurred and as many as 17 patients (73.9%) replied that they would like to continue to use the heat pad in the future.Conclusion:There have been few reports evaluating the usefulness of a heat pad for RP. The wrist mounted disposable heat pad was thought to be a heating method having the potential to achieve high levels of usability and practicality on CTD patients presenting with RP. Given that the heat pad alleviated RP or caused sites other than where the pad was mounted to be felt warm even though it did not directly heat the hands and fingers, the pad seemed to have usefulness attributed to the heating of the wrist. Although the heat pad seems to be an excellent method for addressing RP in patients’ daily lives, we hope that this heat pad will be evaluated on a larger number of patients with the addition of objective indices.References:[1]Koscheyev VS, et al. Aviat Space Environ Med. 72: 713-719, 2001.Disclosure of Interests:Naoto Azuma: None declared, Tetsuya Furukawa: None declared, Yoshihito Shima Grant/research support from: Endowed chair funded by/accepted a researcher from Kirikai Chemical and Kobayashi Pharmaceutical., Kiyoshi Matsui Grant/research support from: Asahi Kasei Pharma, Astellas Pharma (research grants), Speakers bureau: Bristol-Myers Squibb (lecture fees)

Systemic sclerosis (SSc) is a connective tissue disease, the pathogenesis of which is thought to involve interleukin-6 (IL-6), an inflammatory cytokine. This is based on findings of its concentration in patient serum, the results of an IL-6 suppression experiment in an animal model, and the results of a pilot study using IL-6 receptor antibody. However, it appears that a number of factors are involved in the pathology of SSc depending on the state of disease progression. In addition, the degree of involvement of IL-6 differs depending on the difference of organs within particular severe symptoms. Based on the findings from measurements of patient serum, the influence of IL-6 on the pathogenesis of SSc is greater in patients at a relatively early phase of the disease and in patients with lung lesions. Interleukin-13 (IL-13) is one of pro-fibrotic factors, and it is afraid that SSc patients with higher IL-13 have already lost the influence of IL-6. Therefore, although a clinical trial using the anti-IL-6 receptor antibody tocilizumab is underway, it is important to recognize the state of SSc patients prior to selecting treatment.

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.

The retention of the anti-rheumatic agent tocilizumab (TCZ) has not been well documented in patients with rheumatoid arthritis (RA). We conducted an observational study to compare the retention of TCZ and anti-tumour necrosis factor (TNF) drugs in the treatment of patients with RA.We reviewed continuation rates and causes of discontinuation of biological agents (biologics) by assessing medical records of patients with RA who were administered biologics at our institute from September 1999 to April 2012, using the Osaka University Biologics for Rheumatic Diseases (BiRD) registry.A total of 401 patients were included. TCZ, infliximab (IFX), etanercept (ETN), and adalimumab (ADA) were administered to 97, 103, 143, and 58 patients, respectively. There were some differences between the baseline characteristics of the groups. The median duration (range) of TCZ, IFX, ETN, and ADA administration was 2.5 (0.1-12.6), 1.9 (0.0-7.7), 2.9 (0.0-11.3), and 1.3 (0.0-3.4) years, respectively. Continuation rates for TCZ and ETN were significantly higher than those for IFX and ADA. Multivariate analyses showed that discontinuation due to lack or loss of efficacy was significantly less common in the TCZ group than in the other groups. Discontinuation due to overall adverse events was not significantly different between treatment groups.TCZ and ETN show better retention than IFX or ADA in the treatment of RA.

Treatment of refractory Takayasu arteritis (TA) remains an unresolved clinical issue. Patients usually respond to glucocorticoid (GC) therapy, but often relapse on tapering of the GC dose. The aim of the present study was to assess the safety and efficacy of the interleukin-6 (IL-6) receptor antibody tocilizumab (TCZ) in patients with TA refractory to conventional therapies including GC. Four patients with TA who had shown GC resistance received TCZ infusions (8 mg/kg) every 4 weeks a total of at least 24 times (range, 24 to 51). Clinical symptoms, the serum levels of acute phase proteins and IL-6, GC dosage necessary to maintain remission, and cross-sectional imaging by enhanced CT and MRI were assessed. All patients achieved good clinical response and rapid normalization of the acute phase proteins such as C-reactive protein and serum amyloid A during the therapy with TCZ. The mean dosage of prednisolone could be reduced from 21.3 mg/day to 1.5 mg/day. Although the serum IL-6 level was transiently elevated in all patients after several TCZ infusions, it gradually recovered to the initial level. Along with the decrease of serum IL-6, two patients exhibited significant reduction in thickened arterial lesions. No drug-related adverse effects were noted. In this small group of patients with refractory TA, TCZ therapy was effective and well-tolerated. Further larger studies should be conducted to confirm this finding.

Objective This study aimed to validate the Japanese version of the LupusPRO questionnaire for use with systemic lupus erythematosus patients. Methods Participants were 205 lupus patients recruited from three rheumatology centers in Japan. Demographic data were collected and quality of life was assessed using the LupusPRO and the Short Form Health Survey-12. Disease activity was evaluated by physicians using the Systemic Lupus Erythematosus Activity Index. Some participants completed questionnaires 10–14 days after the first survey. Internal consistency reliability, test-retest reliability, content validity and convergent validity were examined, and confirmatory factor analysis was performed. Results Participants’ mean age was 47.8 ± 13.6 years. Older participants scored lower on physical quality of life and higher on coping than younger participants. The LupusPRO showed satisfactory test-retest reliability ( n = 111). Test-retest reliability was lower for the mental and social aspects of quality of life, indicating fluctuations in quality of life during the two-week interval. Internal consistency reliability was good and convergent validity with the corresponding domains of the Short Form Health Survey-12 was satisfactory. Confirmatory factor analysis showed a good model fit. Conclusion The Japanese LupusPRO is a reliable and valid measure to evaluate treatment interventions for systemic lupus erythematosus.

Sleep problems are common in patients with systemic lupus erythematosus (SLE). This study aimed to examine the following: (1) predictors of sleep quality and (2) fluctuations in sleep quality in patients with SLE. Patients with SLE were recruited from three rheumatology centers in Japan. We collected demographic and clinical data and data on sleep quality as measured by the Pittsburgh Sleep Quality Index (PSQI), the Medical Outcome Study Short Form-12, and the Lupus Patient Reported Outcome Tool (LupusPRO). Fluctuations in sleep quality were examined by administering the PSQI a second time after a 2-week interval. We used multiple linear regression analysis to predict sleep quality. Of 205 patients who completed the survey, 62.9% showed poor sleep quality. The largest fluctuation in sleep quality was for "waking in the middle of the night or early morning." "LupusPRO pain/vitality" was a major predictor of poor sleep. The other significant predictors were mostly LupusPRO subscales and clinical variables and SF-12 subscales were mostly non-predictive. The majority of the participants had poor sleep quality. A lupus-specific QoL scale is important for understanding poor sleep quality in SLE patients. Symptom management appeared to play a key role in improving sleep quality.

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease that mainly affects the joints. Many rheumatologists have recently correlated the pathogenesis of RA with the citrullination of ...

B-cell receptor (BCR) signaling plays a critical role in B-cell activation and humoral immunity. In this study, we discovered a critical function of leucine-rich repeat kinase 1 (LRRK1) in BCR-mediated immune responses. Lrrk1−/− mice exhibited altered B1a-cell development and basal immunoglobulin production. In addition, these mice failed to produce IgG3 antibody in response to T cell–independent type 2 antigen due to defects in IgG3 class-switch recombination. Concomitantly, B cells lacking LRRK1 exhibited a profound defect in proliferation and survival upon BCR stimulation, which correlated with impaired BCR-mediated NF-κB activation and reduced expression of NF-κB target genes including Bcl-xL, cyclin D2, and NFATc1/αA. Furthermore, LRRK1 physically interacted and potently synergized with CARMA1 to enhance NF-κB activation. Our results reveal a critical role of LRRK1 in NF-κB signaling in B cells and the humoral immune response.

Interleukin-6 (IL-6), originally identified as a B cell differentiation factor, is a typical cytokine featuring redundancy and pleiotropic activity. IL-6 provides a warning signal and participates in host defense against acute environmental stress such as infections and injuries by inducing immune responses, hematopoiesis and acute-phase reactions. However, its abnormal persistent production plays an important pathological role in the development of various immune-mediated diseases through its pleiotropic activity, in particular induction of an imbalance of CD4 positive effector subsets (Th17 >> regulatory T cells), and autoantibody production. IL-6 blockade was thus expected to constitute a novel strategy for the treatment of diseases and to this purpose tocilizumab (TCZ), a humanized anti-IL-6 receptor monoclonal antibody, was developed. World-wide clinical trials have proved the efficacy and tolerable safety of TCZ for patients with moderate-tosevere rheumatoid arthritis and it is now used as an innovative biologic for rheumatoid arthritis in more than 90 countries. Moreover, findings of recent pathological analyses of other immune-mediated diseases as well as favorable results of pilot or case studies with off-label use of TCZ strongly imply that IL-6 blockade strategy will be broadly applicable for the treatment of various systemic autoimmune diseases including systemic lupus erythematosus, systemic sclerosis, polymyositis and large-vessel vasculitis, as well as of chronic inflammatory diseases such as polymyalgia rheumatica and Bechet’s disease.

A 47-year-old female patient with Behcet’s disease had been treated with colchicine, prednisolone, cyclosporine A, and infliximab. Because she relapsed, however, treatment with tocilizumab, a humanized anti-interleukin 6 receptor antibody, was started. This treatment suppressed the patient’s clinical manifestations, including ocular attacks, for 1 year and improved her visual acuity. This experience indicates that tocilizumab may constitute a therapeutic option for refractory Behcet’s disease.

The cytokine interleukin (IL)-6 has a wide range of biological activities. It contributes to host defense against pathogens by inducing immune responses, hematopoiesis, and acute-phase reactions. However, dysregulation of IL-6 production plays a significant pathological role in various autoimmune and chronic inflammatory disorders. Because IL-6 blockade was anticipated to provide a novel strategy for the treatment of such diseases, tocilizumab, a humanized anti-IL-6 receptor antibody, was developed. Clinical trials have demonstrated the efficacy of tocilizumab for patients with moderate to severe rheumatoid arthritis, resulting in approval in more than 90 countries worldwide of this innovative biologic for the treatment of rheumatoid arthritis. Tocilizumab was also approved in Japan for the treatment of Castleman's disease and juvenile idiopathic arthritis. Results of recent pilot or case studies have indicated that tocilizumab may become a novel drug for various other autoimmune disorders, including systemic lupus erythematosus, systemic sclerosis, polymyositis, and vasculitis syndrome, as well as inflammatory disorders such as adult-onset Still's disease, Crohn's disease, amyloid A amyloidosis, polymyalgia rheumatica, and spondylarthritides. It has been demonstrated that an imbalance of CD4-positive T-helper subsets [Th17 and/or Th1 >> regulatory T cells (Treg)] plays a major role in the development of several autoimmune disorders. In murine models of autoimmune disorders, the anti-IL-6 receptor antibody induced Treg and inhibited Th17 and/or Th1 differentiation, indicating that tocilizumab treatment may be able to repair this imbalance in human diseases as well. Drug Dev Res 72:717–732, 2011. © 2011 Wiley Periodicals, Inc.

Several lines of evidence have suggested that pancreatic β-cell destruction is caused by inflammatory cellular responses mediated by T lymphocytes in individuals with type 1A diabetes. B lymphocytes, which play an important role in the production of autoantibodies to β-cell antigens such as insulin, glutamic acid decarboxylase (GAD) or insulinoma associated antigen 2 (IA-2) in type 1A diabetes, are also known as professional antigen-presenting cells and T-lymphocyte activators. Here, we report a case of long-standing autoimmune type 1 diabetes with common variable immunodeficiency, which is known as a functional deficiency of B lymphocytes. A 51-year-old man was admitted to our hospital because of hyperglycemia. He had suffered from frequent bacterial infections from early childhood. At 16 years old, he was diagnosed with common variable immunodeficiency. At age 27, he experienced sudden-onset diabetic ketosis and was diagnosed with type 1 diabetes. Enzyme-linked immunospot (ELISPOT) assay recently revealed that interferon-γ-producing T lymphocytes but not interleukin 4-producing T lymphocytes, which react with GAD and insulin B1-18, were present at increased levels in his peripheral blood at 51 years old. This case represents the longest reported interval between onset of type 1 diabetes and confirmation of cell-mediated autoimmunity against pancreatic β-cells in a patient with common variable immunodeficiency.

Ankylosing spondylitis (AS) is a chronic inflammatory osteoarticular disease. Although the etiology remains unknown, proinflammatory cytokines, such as tumor necrosis factor α and interleukin-6, have been implicated in the development of AS. Here, we report that a patient with AS, whose disease had been refractory to conventional treatment regimens and who needed to receive continuous corticosteroid, responded well to tocilizumab. While further clinical evaluation is required, tocilizumab may be an optional treatment for AS.

Interferon gamma (IFN-gamma) production is a critical step of antituberculosis (anti-TB) immune response. The purpose of this study was to determine the influences of biologics, including the interleukin (IL)-6 receptor-inhibitor tocilizumab (TCZ), and tumor necrosis factor (TNF) antagonists infliximab (INF) and etanercept (ETA), on Mycobacterium tuberculosis (MTB) antigen-induced IFN-gamma production. MTB antigen (ESAT-6 and CFP-10)-induced IFN-gamma-releasing assay was performed with or without addition of biologics (TCZ, ETA, and INF) using whole blood from patients with active TB. ETA and INF inhibited IFN-gamma production in a dose-dependent manner. In whole blood from TB patients, ESAT-6 stimulated significant production of IFN-gamma (1.30 +/- 1.95 IU/ml), and TCZ did not inhibit IFN-gamma production (1.56 +/- 1.88 IU/ml). IFN-gamma production by ESAT-6 was inhibited by ETA and INF (0.98 +/- 1.74, 0.75 +/- 1.66 IU/ml, respectively). CFP-10 stimulated significant production of IFN-gamma (1.46 +/- 1.60 IU/ml), and TCZ did not inhibit IFN-gamma production (1.51 +/- 1.77 IU/ml). IFN-gamma production by CFP-10 was inhibited by ETA and INF (0.91 +/- 0.99, 0.72 +/- 0.88 IU/ml, respectively). TCD did not inhibit MTB antigen-induced IFN-gamma production. As IFN-gamma production is important in antimycobacterial host defenses, the minimal influence of TCZ on IFN-gamma-releasing assay suggests a low risk of latent TB infection reactivation during tocilizumab therapy.

Overgrowth of the synovium plays an important role in the pathogenesis of rheumatoid arthritis (RA). Platelet-derived growth factor (PDGF) is one of the most potent mitogenic factors of synovial cells, and imatinib mesylate (imatinib) is a specific inhibitor of the PDGF receptor tyrosine kinase. The aim of this study was to elucidate the anti-rheumatic activity of imatinib. The in vivo effects of imatinib were assessed by evaluating the sequential manifestation of adjuvant-induced arthritis in rats using paw volume and clinical scores. Imatinib was found to inhibit rat adjuvant-induced arthritis, but the inhibitory effects were incomplete. To confirm the mechanism of anti-rheumatic-activity of imatinib, we assessed the in vitro effects of imatinib on the proliferation of RA synovial fibroblast-like cells (RASFs) using a MTT assay. Intracellular signaling of PDGF was evaluated by Western blot analysis. Platelet-derived growth factor was found to induce a significant proliferation of RASFs, while imatinib inhibited PDGF-induced proliferation of RASF. Imatinib also inhibited PDGF-induced phosphorylation of the PDGF receptor and Akt, whereas constitutive activated extracellular signal-regulated kinase was not inhibited by imatinib. In contrast, imatinib did not inhibit transforming growth factor beta- and basic fibroblast growth factor-induced proliferation of RASF. Oral administration of imatinib ameliorated adjuvant-induced arthritis in rats, and it inhibited PDGF-induced RASF proliferation through disruption of the PDGF-R to Akt kinase signaling pathway. Because imatinib cannot inhibit the non-PDGF-dependent proliferation of RASFs, the anti-rheumatic effect of imatinib may be incomplete. The development of inhibitors of RASF proliferation may lead to the successful treatment of RA.

Background: Flavonoids are nutrients that exert anti-allergic effects. We investigated the preventative effect of enzymatically modified isoquercitrin (EMIQ), a flavonoid, to relieve the symptoms of Japanese cedar pollinosis. Methods: In a parallel-group, double-blind placebo-controlled study design, 24 subjects with Japanese cedar pollinosis took 100 mg EMIQ or a placebo for 8 weeks, starting 4 weeks prior to the onset of pollen release. Subjective symptoms, ADL scores and the usage of drugs were recorded daily, and the QOL score was obtained every 4 weeks. Blood sampling was performed before and after the study to measure serum levels of IgE and flavonoids. Results: During the entire study period, ocular symptom + medication score for the EMIQ group was significantly lower (p < 0.05) than that of the placebo group. When limited to the period, ocular symptom scores (p < 0.05, weeks 5–6), and ocular congestion scores (p < 0.05, weeks 5–6) for the EMIQ group was significantly lower than that for the placebo group while other scores for the EMIQ group, such as ocular itching scores (p = 0.09, weeks 4–5), lacrimation scores (p = 0.07, weeks 5–6), and ocular congestion scores (p = 0.06, weeks 45), all tended to be lower. However no significant differences were found in nasal symptoms between the two groups. Serum concentrations of IgE were not significantly downregulated but the serum concentrations of quercetin and its derivatives were elevated significantly by the intake of EMIQ. Conclusions: Intake of the quercetin glycoside EMIQ proved to be effective for the relief of ocular symptoms caused by Japanese cedar pollinosis.

Background: Flavonoids exert antiallergic and antioxidant effects. We investigated the efficacy of enzymatically modified isoquercitrin (EMIQ), a flavonoid, to relieve symptoms of pollinosis. Methods: In a parallel-group, double-blind placebo-controlled study design, 20 subjects with Japanese cedar pollinosis took two capsules daily of 100 mg EMIQ or a placebo for 8 weeks during the pollen season. Subjective symptoms and activities of daily living (ADL) scores were recorded every day, and the quality of life (QOL) score was obtained every 4 weeks. Blood sampling was performed before and after the study to measure serum cytokines, chemokines, IgE, quercetin and oxidized biomarkers. Results: During the entire study period, total ocular score and ocular itching score for the EMIQ group were significantly lower (p < 0.05) than for the placebo group. When limited to the individual periods, total symptom score for the EMIQ group was significantly lower (p < 0.05, week 4–5) than that for the placebo group while other scores for the EMIQ group, such as total nasal score (p = 0.06, week 4–5), nasal obstruction score (p = 0.08, week 4–5), lacrimation score (p = 0.06, week 5–6), ocular congestion score (p = 0.08, week 4–7) and ADL score (p = 0.08, week 4–7), all tended to be lower. The levels of serum cytokines such as interleukin (IL)-4, IL-5, IL-12, IL-13, interferon-γ, and eotaxin and IgE were not significantly downregulated by the intake of EMIQ but the serum concentrations of oxidized low-density lipoprotein and thymus and activation-regulated chemokine were reduced. Conclusion: Intake of the quercetin glycoside EMIQ was safe and influenced ocular symptoms caused by pollinosis.

Interleukin-6 (IL-6) is a pleiotropic cytokine that acts in the development of B-lymphocytes; the proliferation of megakaryocytes, mesangial cells, and keratinocytes; and the production of acute-phase proteins such as C-reactive protein (CRP). Many reports suggest that IL-6 plays a partial role in the pathogenesis of systemic sclerosis (SSc). Here, I describe its functions, signal transduction pathways, and involvement in SSc and then introduce an anti-IL-6 therapy for SSc using an anti-IL-6 receptor antibody, tocilizumab. To evaluate the effect of such an anti-cytokine therapy, a large-scale study is needed. And a worldwide-scale study may require a new evaluation method to suppress inter-institute variability.

The patient was a 33 year female. In 2001, she was diagnosed with systemic lupus erythematosus (SLE) and treated with prednisolone and ciclosporin. In May 2006, she noticed slight muscle weakness in the bilateral lower limbs. In July of the same year, she experienced gait difficulty and was admitted to our hospital because of fatigue, appetite loss, fever and disorientation. Soon afterwards, she had a fit of general convulsion and suffered from urinary retention and fecal incontinence. A brain magnetic resonance image revealed atrophy of the thoracic cord in T2 weighted images, and cerebrospinal fluid examination showed high total protein and interleukin-6 concentration, indicating complication of lupus myelitis as well as cerebral involvement. Steroid pulse and oral prednisolone treatment resulted in ameriolation of cerebral complications such as disorientation and convulsion, but muscle weakness and paresthesia in the lower limbs and urinary retention persisted. Cyclophosphamide pulse therapy was started and resulted in a marked recovery from muscle weakness, paresthesia and urinary retention, and she could discharge. We conclude that steroid and cyclophosphamide pulse therapy for a SLE patient with CNS lupus and lupus myelitisis is effective for ameriolation of symptoms such as disorientation, convulsion, urinary retension, fecal incontinence, muscle weakness and paresthesia in the lower limbs as well as elevated level of serum anti-ribosomal P antibody.

We previously demonstrated a significant association between IL-18 gene polymorphism 105A/C and asthma. In this study, we investigated the relationship of IL-18 gene polymorphism to IL-18 production capability by monocytes. The frequency of gene polymorphisms including IL-18-105A/C and IL-18--137G/C was determined by PCR analyses. The IL-18 production by monocytes stimulated without or with LPS or A23187+PMA for 1day was measured by ELISA. The produced IL-18 spontaneously or in response to A23187+PMA by monocytes was significantly higher for volunteers with 105A/A genotype than with 105A/C genotype. Similarly, the production capability of IL-18 by monocytes from volunteers with -137G/G genotype was significantly higher than that with -137G/C genotype and significant linkage disequilibrium was observed between 105A/C and -137G/C polymorphism. Thus, the genetic capacity to produce more IL-18 in response to stimuli may affect the onset of asthma.

Flavonoids including luteolin, apigenin, and fisetin are inhibitors of IL-4 synthesis and CD40 ligand expression by basophils. This study was done to search for compounds with greater inhibitory activity of IL-4 expression and to clarify the molecular mechanisms through which flavonoids inhibit their expression. Of the 37 flavonoids and related compounds examined, ayanin, luteolin, and apigenin were the strongest inhibitors of IL-4 production by purified basophils in response to anti-IgE antibody plus IL-3. Luteolin did not suppress Syk or Lyn phosphorylation in basophils, nor did suppress p54/46 SAPK/JNK, p38 MAPK, and p44/42 MAPK activation by a basophilic cell line, KU812 cells, stimulated with A23187 and PMA. However, luteolin did inhibit phosphorylation of c-Jun and DNA binding activity of AP-1 in nuclear lysates from stimulated KU812 cells. These results provide a fundamental structure of flavonoids for IL-4 inhibition and demonstrate a novel action of flavonoids that suppresses the activation of AP-1.

Background: We have previously shown that flavonoids such as luteolin, apigenin and fisetin inhibit interleukin 4 and interleukin 13 production. In this study, we investigated whether luteolin can suppress CD40 ligand expression by basophils. Methods: A human basophilic cell line, KU812, was stimulated with A23187 and phorbol myristate acetate (PMA) with or without various concentrations of luteolin or other flavonoids for 12 h, and CD40 ligand expression was analyzed by FACS. The effect of luteolin on CD40 ligand mRNA expression was studied by semiquantitative reverse transcription PCR analysis. In addition, CD40 ligand expression was also measured in purified basophils that had been stimulated for 12 h with A23187 plus PMA with or without various concentrations of luteolin. Results: CD40 ligand expression by KU812 cells was enhanced noticeably in response to A23187 and even more strikingly augmented by A23187 plus PMA. The expression was significantly suppressed by 10 or 30 µM of luteolin, whereas myricetin failed to inhibit. Reverse transcription PCR analyses demonstrated that luteolin inhibited CD40 ligand mRNA expression by stimulated KU812 cells. Of the six flavonoids examined, luteolin, apigenin, fisetin and quercetin at 30 µM showed a significant inhibitory effect on CD40 ligand expression. The incubation of purified basophils with A23187 plus PMA significantly enhanced CD40 ligand expression, and the presence of luteolin again had an inhibitory effect. Conclusions: Luteolin inhibits CD40 ligand expression by activated basophils.

All-trans-retinoic acid (ATRA), a vitamin A derivative, was reported to suppress the interleukin-6 (IL-6) production and to downregulate the IL-6 receptor (IL-6R) and/or its signal transducer glycoprotein 130. We investigated the in vivo antinephritic effect of ATRA on IL-6 transgenic mice which had developed mesangial proliferative glomerulonephritis (PGN) as well as its in vitro inhibitory effect on the proliferation of rat mesangial cells. In vivo experiments on IL-6 transgenic mice showed that ATRA administration suppressed proteinuria and hematuria and reduced the IL-6 concentrations; furthermore, histological examination demonstrated that it improved PGN. In vitro experiments using rat mesangial cells demonstrated that ATRA inhibited cell growth in a dose-dependent manner within a range from 10–4 to 10–6M. This inhibition by ATRA was partially counteracted by the addition of IL-6. RT-PCR assay results showed that ATRA also reduced IL-6R, but not the glycoprotein 130 expression in mesangial cells. These findings indicate that, by blocking of the IL-6 function, ATRA may be therapeutically effective in PGN.

The granuloma is a host defence response to persistent pathogenic irritants. In the process of granuloma formation, the activation, migration, and fusion of macrophages occur locally, but the mechanisms involved remain elusive. Tetraspanins regulate cell migration and fusion by organizing functional molecular complexes in membrane microdomains. Here we investigated the role of tetraspanin CD9 in hepatic granuloma formation. Immunostaining of the liver of untreated wild-type mice showed that CD9 was expressed by vascular endothelial cells and perivenular hepatocytes. When intrahepatic granulomas were induced by intravenous injection of Propionibacterium acnes, hepatocyte CD9 was extensively upregulated, while inflammatory cells constituting granulomas were mostly negative for CD9. Compared with wild-type littermates, CD9-knockout mice showed dissemination of Propionibacterium acnes and reduced number and size of granulomas after the injection. Moreover, production of granuloma-inducing cytokines, TNF-alpha and IFN-gamma, was delayed and chemotactic activity for macrophages was suppressed in the liver of mutant mice. These results suggest that CD9 is one of the proteins that promotes granuloma formation in the liver.

Clonotypic B cells circulating in patients with multiple myeloma (MM) express CD20, and it has been suggested that these cells may be clonogenic. Furthermore, 20% of patients with MM express CD20 on their bone marrow plasma cells (BMPCs). Therefore, the authors began a phase II clinical study to determine the activity of the anti-CD20 monoclonal antibody rituximab in MM patients. Nineteen previously treated MM patients received 375 mg/m2 rituximab per week for 4 weeks. Three months after initiation of treatment, patients were assessed for response and received a second course of therapy if their disease was stable (SD) or they achieved a partial response (PR). Six of 19 (32%) patients had either a PR (n = 1) or SD (n = 5), with a median time to treatment failure of 5.5 months (mean, 10.3 months; range, 3-27+ months). All six patients who had a PR or SD had CD20+ BMPC. Overall, rituximab therapy was well tolerated. Because most patients with MM poorly express CD20 on their BMPCs, the authors evaluated agents for their ability to induce CD20 expression and thereby facilitate rituximab binding on MM cells. These studies show that interferon-gamma (IFN-y) induced CD20 expression on MM BMPCs, MM B cells, and healthy donor BMPCs. In contrast, CD20 expression on chronic lymphocytic leukemia, follicular non-Hodgkin's lymphoma, healthy donor B cells, and progenitor cells was unaffected by IFN-y. Rituximab binding to the BMPCs of MM patients was also increased after culture with pharmacologically attainable levels of IFN-gamma (1-100 U/mL). In conclusion, these studies suggest that MM patients with CD20+ BMPCs may benefit from rituximab therapy. Furthermore, IFN-gamma induces CD20 expression on MM BMPCs and B cells and facilitates rituximab binding to MM BMPCs, providing the rationale for clinical trials to examine its use with CD20-directed serotherapies in MM.

Clowse et al 1 have reported minimal to no transfer of certolizumab pegol (CZP) into breast milk, and their findings have supported the continuation of CZP treatment during breast milk feeding. Rheumatoid arthritis (RA) often develops in women of childbearing age. It is generally difficult to treat these patients with methotrexate, which is the anchor drug for RA. Therefore, biologics, such as tumour necrosis factor (TNF) inhibitors, are often considered for active RA during pregnancy. However, the biologics cross the placenta from mother to fetus and transfer into breast milk during lactation. Although a meta-analysis report indicated that anti-TNF-α therapy did not increase the risks, such as congenital malformation or abortion during pregnancy, in patients with inflammatory …