Placenta Specific 8 Suppresses IL-18 Production through Regulation of Autophagy and Is Associated with Adult Still Disease.

Adult Still disease (ASD) is a systemic disorder of unknown etiology characterized by high spiking fever, rash, and arthritis. The purpose of this study was to identify genes specifically associated with the active phase of the disease. In this study, we have reported that placenta specific 8 (PLAC8) was a newly specific gene involved in ASD. DNA microarray and validation analysis using human monocytes revealed that the expression of PLAC8 was significantly higher in active-ASD patients than in inactive-ASD patients and healthy controls. In ASD, PLAC8 expression level correlated with serum levels of CRP, ferritin, IL-1ß, and IL-18. Stimulation of monocytes with LPS results in PLAC8 upregulation. LPS or nigericin stimulation of PLAC8-overexpressing human monocytic cell line (THP-1), but not mock THP-1 cells, was associated with a significant decrease in IL-1ß and IL-18 production. PLAC8 overexpression in THP-1 cells was associated with enhanced autophagy and suppression of IL-1ß and IL-18 production. Therefore, we found that PLAC8 was upregulated in activated monocytes, as was IL-1ß and IL-18. The upregulated PLAC8 acts on the synthesis of inactive precursors of IL-1ß and IL-18 and seemed to suppress the production of IL-1ß and IL-18 by negative feedback through enhanced autophagy, resulting in the suppression of ASD. The results highlight the role of PLAC8 in the pathogenesis of ASD and suggest its potential suitability as an activity marker and therapeutic target in ASD.

Potential involvement of OX40 in the regulation of autoantibody sialylation in arthritis.

OBJECTIVE: An increased proportion of circulating follicular helper T (Tfh) cells was reported in rheumatoid arthritis (RA), but it remains uncertain how Tfh cells affect antibody hyposialylation. We investigated the regulation of autoantibody hyposialylation by Tfh cells in RA using murine model. METHODS: Behaviours of Tfh cells and their function on B cell promotion were analysed. Change of arthritogenicity and sialylation of autoantibodies during the course of arthritis was examined by mass spectrometry. Tfh-mediated regulation of hyposialylation was investigated, and the responsible cell surface molecule was specified both in vitro and in vivo. The relation between circulating Tfh cells and hyposialylation was analysed in patients with RA. RESULTS: An increase in Tfh, particularly interleukin-17 producing Tfh (Tfh17) cells, at the onset of arthritis and their enhancement of autoantibody production were found. Autoantibodies at the onset phase demonstrated stronger inflammatory properties than those at the resolution phase, and mass spectrometric analysis revealed their difference in sialylation. In vitro coculture showed enhanced hyposialylation by the Tfh cells via OX40, which was highly expressed in the Tfh and Tfh17 cells. Blockade of OX40 prevented the development of arthritis with reduction in Tfh17 cells and recovery of autoantibody sialylation. Analysis of patients with RA showed abundance of OX40-overexpressing Tfh17 cells, and their proportion correlated negatively with the expression of α2,6-sialyltransferase 1, an enzyme responsible for sialylation. CONCLUSIONS: OX40 expressed on Tfh cells can regulate autoantibody sialylation and play a crucial role in the development of autoimmune arthritis.

The RORγt-CCR6-CCL20 axis augments Th17 cells invasion into the synovia of rheumatoid arthritis patients.

OBJECTIVES: To clarify the pathogenic role of transcription factor expression of CD4 + T helper (Th) cell subsets in the development of rheumatoid arthritis (RA). METHODS: We collected CD4 + T cells from peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) by magnetic cell sorting. The proportion of Th cell subsets were classified from cell surface markers (CD45RA, CXCR5, CXCR3, CCR6) and the expression of their transcription factors (T-bet, GATA3, RORγt) were analyzed by flow cytometry before and at 24 weeks after anti-rheumatic treatment. Chemotaxis assays quantified migratory ability. RESULTS: The expression of CCR6 and RORγt in Th17 cells from PBMC of RA patients was significantly higher than in healthy control volunteers and osteoarthritis patients. The proportion of Th17 cells in SFMCs of RA patients was significantly higher than that in PBMCs. Chemotaxis assays revealed that the migration index of Th17 cells towards CCL20 was remarkably enhanced in RA patients. The expression of CCR6 and RORγt in Th17 cells at 24 weeks post-therapeutic intervention was significantly decreased compared to before treatment. CONCLUSION: The high expression of RORγt might facilitate the migration of Th17 cells to inflamed joints via the enhanced expression of CCR6 and contribute to the pathology of RA.

Evidence-based clinical practice guideline for adult Still's disease.

OBJECTIVES: Using an expert- and data-driven methodology, we have constructed the first clinical practice guidelines (CPGs) for adult Still's disease (ASD) after complete systematic review (SR) of the literature based upon the Medical Information Network Distribution Service (Minds) procedure. METHODS: The CPG committee for ASD organized by the Research Team for Autoimmune Diseases, the Research Program for Intractable Disease of the Japanese Ministry of Health, Labour, and Welfare has developed CPG for ASD 2017, according to the procedure proposed by Minds. The CPG development process includes (1) clarification of the purpose of CPG, (2) organization of the steering committee, (3) organization of the CPG committee and secretariat, (4) defining the scope (setting of clinical questions (CQs)), (5) SR, (6) development of recommendations, (7) drafting the CPG, (8) external evaluation and public comments, and (9) release. Because we wanted to construct CPG for ASD to encompass both adult-onset Still's disease (AOSD) and adult patients with systemic juvenile idiopathic arthritis (sJIA), we also included SR data from sJIA in this study. RESULTS: Twenty-six CQs were selected and roughly divided into the following items: (1) clinical findings (CQs 1-4), (2) laboratory findings (CQs 5-8), (3) complications (CQs 9-13), (4) treatment with oral medicine (CQs 14-19), (5) treatment with biological reagents (CQs 20-23), and (6) treatments for sJIA (CQs 25-26). Recommendations and the strength of the recommendations for these CQs were decided by a modified Delphi method. CONCLUSION: We have developed the first published CPG for ASD including AOSD and sJIA, which includes 26 CQs and recommendations. This guideline will help rheumatologists, non-specialized physicians, other healthcare providers, medical and health-related students, and patients and their family members to understand and treat ASD.

Successful tocilizumab therapy in seven patients with refractory adult-onset Still's disease.

To evaluate the effects of tocilizumab (TCZ) on adult-onset Still's disease (AOSD), we reviewed medical records of seven patients with refractory AOSD treated with TCZ at our institution. TCZ therapy might allow rapid corticosteroid tapering and help maintain remission status, that is, resolution of clinical symptoms and normalization of biomarkers such as CRP and ferritin. Patients, however, should be monitored for the development of macrophage activation syndrome when TCZ is administered for active AOSD.

[Rheumatoid arthritis and cytokines].

The cytokines are an important substance involved in the immune reaction and maintenance of homeostasis. An imbalance in the cytokine network may lead to inflammation and autoimmune diseases such as rheumatoid arthritis (RA). RA is an autoimmune and systemic inflammatory disorder characterized by synovial inflammation, destruction of cartilage and bone and systemic manifestations. The pro-inflammatory cytokines such as tumor necrosis factor α (TNFα), interleukin-1 (IL-1), IL-6 and IL-17 induce the inflammation of the joints and destruction of bone and cartilage via activation of macrophages, fibroblast like synoviocytes (FLS), helper T (Th) cells and osteoclasts. Recently, the available therapeutic agents that target these cytokines have excellent clinical effects in RA patients.

[Rheumatic joint diseases in the elderly].

The most frequent rheumatic joint disease in the elderly is rheumatoid arthritis (RA). Recent advances in the treatment of RA improve prognosis, and gradually increase the elderly patients with RA. There are some differences in clinical features between the patients with elderly onset RA and young onset RA, such as systemic symptoms and distribution of affected joints. In addition, it is occasionally difficult to differentiate elderly onset RA from the other rheumatic diseases like polymyalgia rheumatica and RS3PE syndrome, pseudogout, and osteoarthritis. Since elderly patients tend to have more co-morbidity and co-existing diseases requiring treatment with other drugs, a risk/benefit profile must always be taken into consideration when choosing the treatment in elderly patients with rheumatic joint diseases.

Review: Transcriptional Regulation of CD4+ T Cell Differentiation in Experimentally Induced Arthritis and Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by chronic inflammation of the joint synovium and infiltration by activated inflammatory cells. CD4+ T cells form a large proportion of the inflammatory cells invading the synovial tissue, and are involved in the RA pathologic process. In general, CD4+ T cells differentiate into various T helper cell subsets and acquire the functional properties to respond to specific pathogens, and also mediate some autoimmune disorders such as RA. Because the differentiation of T helper cell subsets is determined by the expression of specific transcription factors in response to the cytokine environment, these transcription factors are considered to have a role in the pathology of RA. Treg cells control an excess of T cell-mediated immune response, and the transcription factor FoxP3 is critical for the differentiation and function of Treg cells. Treg cell dysfunction can result in the development of systemic autoimmunity. In this review, we summarize how the expression of transcription factors modulates T helper cell immune responses and the development of autoimmune diseases, especially in RA. Understanding the role of transcription factors in the pathogenesis of autoimmunity may lead to novel therapeutic strategies to control the differentiation and function of both T helper cells and Treg cells.

Allergy inhibitory receptor-1 inhibits autoantibody production via upregulation of apoptotic debris clearance by macrophages.

AIM: Allergy inhibitory receptor-1 (Allergin-1) is a newly identified immune regulatory molecule thought to influence autoantibody production. Autoantibody production, like that observed in Allergin-1-deficient mice, is crucial in the pathogenesis of several autoimmune diseases such as systemic lupus erythematosus. The purpose of this study is to clarify the regulatory role of Allergin-1-mediated autoantibody production using a murine model of thymocytic anaphylaxis. METHODS: C57BL/6 (WT) and Allergin-1-deficient mice were treated with apoptotic cells from naive thymocytes stimulated by dexamethasone. Antibody titers of total or immunoglobulin G (IgG) subclass of anti-double-stranded DNA (anti-dsDNA) and anti-histone antibody from serum were measured using an enzyme-linked immunosorbent assay. Macrophages from wild-type (WT) or Allergin-1-deficient mice were co-cultured with fluorescence-labeled apoptotic thymocytes or fluorogenic reagent and resultant phagocytic activity was quantified by with flow cytometry. RESULTS: After apoptotic cells injection, antibody titers of total and IgG3 anti-dsDNA and total anti-histone from serum were significantly increased in Allergin-1-deficient versus WT mice. Phagocytic activity was significantly lower in macrophages from Allergin-1-deficient mice versus WT mice. CONCLUSION: Allergin-1 might play an inhibitory role in autoantibody production via upregulation of macrophage phagocytosis.

Involvement of RORγt-overexpressing T cells in the development of autoimmune arthritis in mice.

INTRODUCTION: Differentiation of T helper 17 cells is dependent on the expression of transcription retinoid-related orphan receptor gamma t (RORγt). The purpose of our study is to determine the role of RORγt expression in T cells on the development of collagen-induced arthritis (CIA). METHODS: CIA was induced in C57BL/6 and T cell-specific RORγt transgenic (RORγt Tg) mice. At day 10 post-1st-immunization, lymph node (LN) cells were cultured with type II collagen (CII), and the expression levels of various cytokines and transcription factors on CD4+ T cells were measured. Total cells or CD4+ cells of draining LN were harvested from each mouse group after CII-immunization and transferred into C57BL/6 mice, and then CIA was induced in recipient mice. The expression levels of RORγt and other surface antigens, and the production of cytokines were analyzed in forkhead box P3 (Foxp3)+ regulatory T (Treg) cells. Foxp3+ Treg cells were analyzed for suppressive activity against proliferation of effector CD4+ T cells. Interlukin (IL)-10 neutralizing antibody was administrated in the course of CIA. RESULTS: CIA was significantly suppressed in RORγt Tg mice compared with C57BL/6 mice. RORγt expression and IL-17 production were significantly higher in CII-reactive CD4+ T cells from RORγt Tg mice. Arthritis was significantly attenuated in C57BL/6 mice recipient of cells from RORγt Tg mice. Most of Foxp3+ Treg cells expressed RORγt, produced IL-10 but not IL-17, and overexpressed CC chemokine receptor 6 (CCR6) and surface antigens related to the suppressive activity of Foxp3+ Treg cells in RORγt Tg mice. In vitro suppression assay demonstrated significant augmentation of the suppressive capacity of Foxp3+ Treg cells in RORγt Tg mice. CIA was exacerbated in both C57BL/6 mice and RORγt Tg mice by the treatment of anti-IL-10 antibody. CONCLUSION: Our results indicated that RORγt overexpression in T cells protected against the development of CIA. The protective effects were mediated, at least in part, through the anti-inflammatory effects including high production of IL-10 of RORγt+Foxp3+ Treg cells.

Rheumatoid arthritis-associated aortitis: a case report and literature review.

Rheumatoid arthritis (RA) is a systemic autoimmune inflammatory disorder that primarily affects the synovial joints. Rheumatoid vasculitis (RV) is an extra-articular manifestation of RA, and its association with aortitis is rare and not widely recognised. Here, we report the case of a 69-year-old woman with RA-associated aortitis and review the literature on rheumatoid aortitis. The mean oral steroid dose administered to RA-associated aortitis patients was 46.3 mg/day prednisolone (PSL). In our patient, the aortitis was also thought to be due to RV because she had findings of RV, such as cutaneous ulceration and a high rheumatoid factor titre, and because a moderate PSL dose dramatically improved the clinical findings. RA-associated aortitis, if left untreated, can be fatal; therefore, early detection and treatment initiation is very important.

Cytomegalovirus disease of the upper gastrointestinal tract in patients with rheumatic diseases: a case series and literature review.

Cytomegalovirus disease of the upper gastrointestinal tract (CMV-UGT) is a rare but significant complication in patients with rheumatic diseases. We reviewed records for January 2004 to December 2012 and investigated the occurrence of CMV-UGT in patients with rheumatic diseases to evaluate clinical characteristics, the value of the CMV antigenemia assay, and the association between immunosuppressive therapy and CMV-UGT. Ten CMV-UGT events (six gastric ulcer, two esophagitis, one gastritis, and one duodenal ulcer) in nine patients (three rheumatoid arthritis, three systemic lupus erythematosus, one dermatomyositis, one systemic sclerosis, and one overlap syndrome) were identified based on pathology. Mean age was 66.5 (range, 53-76) years. The CMV antigenemia assay was negative in five cases (50 %). All ten cases received glucocorticoids and six (60 %) received pulsed glucocorticoids. Mean prednisolone dose was 31.3 (range, 7.5-40) mg/day at diagnosis. Concomitant immunosuppressive agents were used in eight cases (80 %). Considering other published cases, the most common immunosuppressive drug was cyclophosphamide (ten cases; 45 %). Notably, two of our patients who were treated with low-dose glucocorticoids plus other milder immunosuppressive drugs (methotrexate and cyclosporine) also developed CMV-UGT. Life-threatening complications such as massive bleeding or perforated ulcer occurred in two patients. These results suggest that patients receiving intensive immunosuppressive therapy such as high-dose glucocorticoids and cyclophosphamide are at higher risk for developing CMV-UGT. Moreover, CMV-UGT can occur even with low-dose glucocorticoid therapy and relatively mild immunosuppressive agents. The value of the CMV antigenemia assay for predicting CMV-UGT appears to be limited.