Regulation of cytokine and chemokine expression by histone lysine methyltransferase MLL1 in rheumatoid arthritis synovial fibroblasts.

Histone lysine methylation is thought to play a role in the pathogenesis of rheumatoid arthritis (RA). We previously reported aberrant expression of the gene encoding mixed-lineage leukemia 1 (MLL1), which catalyzes methylation of histone H3 lysine 4 (H3K4), in RA synovial fibroblasts (SFs). The aim of this study was to elucidate the involvement of MLL1 in the activated phenotype of RASFs. SFs were isolated from synovial tissues obtained from patients with RA or osteoarthritis (OA) during total knee joint replacement. MLL1 mRNA and protein levels were determined after stimulation with tumor necrosis factor α (TNFα). We also examined changes in trimethylation of H3K4 (H3K4me3) levels in the promoters of RA-associated genes (matrix-degrading enzymes, cytokines, and chemokines) and the mRNA levels upon small interfering RNA-mediated depletion of MLL1 in RASFs. We then determined the levels of H3K4me3 and mRNAs following treatment with the WD repeat domain 5 (WDR5)/MLL1 inhibitor MM-102. H3K4me3 levels in the gene promoters were also compared between RASFs and OASFs. After TNFα stimulation, MLL1 mRNA and protein levels were higher in RASFs than OASFs. Silencing of MLL1 significantly reduced H3K4me3 levels in the promoters of several cytokine (interleukin-6 [IL-6], IL-15) and chemokine (C-C motif chemokine ligand 2 [CCL2], CCL5, C-X-C motif chemokine ligand 9 [CXCL9], CXCL10, CXCL11, and C-X3-C motif chemokine ligand 1 [CX3CL1]) genes in RASFs. Correspondingly, the mRNA levels of these genes were significantly decreased. MM-102 significantly reduced the promoter H3K4me3 and mRNA levels of the CCL5, CXCL9, CXCL10, and CXCL11 genes in RASFs. In addition, H3K4me3 levels in the promoters of the IL-6, IL-15, CCL2, CCL5, CXCL9, CXCL10, CXCL11, and CX3CL1 genes were significantly higher in RASFs than OASFs. Our findings suggest that MLL1 regulates the expression of particular cytokines and chemokines in RASFs and is associated with the pathogenesis of RA. These results could lead to new therapies for RA.

New-onset of rheumatic diseases following COVID-19 vaccination: the report of three cases and a literature review.

Vaccines against coronavirus disease 2019 (COVID-19) have been distributed in most countries for the prevention of onset and aggravation of COVID-19. Recently, there have been increasing numbers of reports on new-onset autoimmune and autoinflammatory diseases following COVID-19 vaccination, however, only little information is available on the long-term safety of these vaccines. Here, we experienced three cases of new-onset rheumatic diseases following COVID-19 vaccination, one case each of rheumatoid arthritis (RA), anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and systemic lupus erythematosus (SLE). The symptom onset ranged from one day to a few days following vaccination. The patients of AAV and SLE were treated successfully with glucocorticoid therapy, and the patient of RA died due to COVID-19. In the literature review of new-onset rheumatic diseases following COVID-19 vaccination, which including seven cases of RA, 37 cases of AAV and 18 cases of SLE, the mean time from vaccination to onset was approximately 11 to 12 days. Most cases improved with glucocorticoid, immunosuppressive drugs and biologic agents. Although such adverse effects are rare, and vaccines are useful in prevent onset and severity of infections, continued accumulation of similar cases is important in terms of examining the long-term safety and understanding pathogenic mechanism of rheumatic diseases.

Epigenetic Dysregulation in the Pathogenesis of Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease in which immune disorders lead to autoreactive immune responses and cause inflammation and tissue damage. Genetic and environmental factors have been shown to trigger SLE. Recent evidence has also demonstrated that epigenetic factors contribute to the pathogenesis of SLE. Epigenetic mechanisms play an important role in modulating the chromatin structure and regulating gene transcription. Dysregulated epigenetic changes can alter gene expression and impair cellular functions in immune cells, resulting in autoreactive immune responses. Therefore, elucidating the dysregulated epigenetic mechanisms in the immune system is crucial for understanding the pathogenesis of SLE. In this paper, we review the important roles of epigenetic disorders in the pathogenesis of SLE.

Essentiality of Nfatc1 short isoform in osteoclast differentiation and its self-regulation.

During osteoclast differentiation, the expression of the transcription factor nuclear factor of activated T cell 1 (Nfatc1) increases in an autoproliferative manner. Nfatc1 isoforms are of three sizes, and only the short isoform increases during osteoclast differentiation. Genetic ablation of the whole Nfatc1 gene demonstrated that it is essential for osteoclastogenesis; however, the specific role of the Nfatc1 short form (Nfatc1/αA) remains unknown. In this study, we engineered Nfatc1 short form-specific knockout mice and found that these mice died in utero by day 13.5. We developed a novel osteoclast culture system in which hematopoietic stem cells were cultured, proliferated, and then differentiated into osteoclasts in vitro. Using this system, we show that the Nfatc1/αA isoform is essential for osteoclastogenesis and is responsible for the expression of various osteoclast markers, the Nfatc1 short form itself, and Nfatc1 regulators.

Successful Treatment of Diffuse Large B-cell Lymphoma Involving Multiple Renal and Bone Infiltrations Presenting with Giant Cell Arteritis-like Manifestations: A Case Report.

We herein report a case of diffuse large B-cell lymphoma (DLBCL) involving multiple renal and bone infiltrations presenting with giant cell arteritis-like (GCA)-like manifestations. One month prior, the present patient had left-sided temporal headache, jaw claudication, and renal failure. The patient was diagnosed with DLBCL based on a renal biopsy. After rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) plus intrathecal methotrexate/cytarabine/prednisone and rituximab, high-dose methotrexate, and cytarabine (R-MA) chemotherapy, the patient's clinical manifestations improved, and complete remission was achieved. DLBCL rarely but occasionally presents with GCA-like manifestations or multiple renal and bone infiltrations, highlighting the need for prompt and aggressive combination chemotherapy.

New-onset Immune-mediated Necrotizing Myopathy and Trigeminal Neuropathy after SARS-CoV-2 mRNA Vaccination in a Patient with Rheumatoid Arthritis and Sjögren's Syndrome.

We present the case of a 42-year-old woman with rheumatoid arthritis and Sjögren's syndrome treated with adalimumab who developed immune-mediated necrotizing myopathy (IMNM) and trigeminal neuropathy after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccination. Trigeminal neuralgia and elevated serum creatine kinase levels emerged 12 days post-vaccination, followed by myalgia in the femoral muscles. IMNM was histologically diagnosed. The pathogenesis may involve molecular mimicry between the SARS-CoV-2 spike glycoprotein and autologous tissues triggered by vaccination. This case emphasizes the association between SARS-CoV-2 vaccination, tumor necrosis factor inhibitor, IMNM, and trigeminal neuropathy, as well as the importance of monitoring immune-mediated adverse events following SARS-CoV-2 vaccination in patients with autoimmune disease.

Synovial Tissue Heterogeneity in Japanese Patients With Rheumatoid Arthritis Elucidated Using a Cell-Type Deconvolution Approach.

OBJECTIVE: Recent advances in single-cell RNA sequencing technology have improved our understanding of the immunological landscape of rheumatoid arthritis (RA). We aimed to stratify the synovium from East Asian patients with RA by immune cell compositions and gain insight into the inflammatory drivers of each synovial phenotype. METHODS: Synovial tissues were obtained from East Asian patients in Japan with RA (n = 41) undergoing articular surgery. The cellular composition was quantified by a deconvolution approach using a public single-cell-based reference. Inflammatory pathway activity was calculated by gene set variation analysis, and chromatin accessibility was evaluated using assay of transposase accessible chromatin-sequencing. RESULTS: We stratified RA synovium into three distinct subtypes based on the hierarchical clustering of cellular composition data. One subtype was characterized by abundant HLA-DRAhigh synovial fibroblasts, autoimmune-associated B cells, GZMK+ GZMB+ CD8+ T cells, interleukin (IL)1-ß+ monocytes, and plasmablasts. In addition, tumor necrosis factor (TNF)-α, interferons (IFNs), and IL-6 signaling were highly activated in this subtype, and the expression of various chemokines was significantly enhanced. Moreover, we found an open chromatin region overlapping with RA risk locus rs9405192 near the IRF4 gene, suggesting the genetic background influences the development of this inflammatory synovial state. The other two subtypes were characterized by increased IFNs and IL-6 signaling, and expression of molecules associated with degeneration, respectively. CONCLUSION: This study adds insights into the synovial heterogeneity in East Asian patients and shows a promising link with predominant inflammatory signals. Evaluating the site of inflammation has the potential to lead to appropriate drug selection that matches the individual pathology.

Relapsing Polychondritis and Aseptic Meningoencephalitis.

We herein report a 49-year-old Japanese man with relapsing polychondritis (RP) and aseptic meningoencephalitis. Four years ago, the patient was diagnosed with RP. Prednisolone (PSL) was started at 30 mg/day, and the symptoms promptly disappeared. However, cognitive impairment gradually appeared from six months before hospitalization. Methylprednisolone pulse therapy was immediately initiated, followed by administration of PSL at 1 mg/kg/day. Intravenous cyclophosphamide was combined with PSL. After treatment, the patient's cognitive impairment clearly improved. In conclusion, RP rarely causes aseptic meningoencephalitis, highlighting the need for prompt and aggressive immunosuppressive therapy.

New-onset Adult-onset Still's Disease Following COVID-19 Vaccination: Three Case Reports and a Literature Review.

Since December 2020, coronavirus disease 2019 (COVID-19) vaccines have been distributed in most countries to prevent the onset and aggravation of COVID-19. There is little information regarding the long-term safety of the vaccines. We report three cases and a literature review of new-onset adult-onset Still's disease (AOSD) that occurred following COVID-19 vaccination. Our cases include moderate to severe AOSD, and two were complicated with macrophage activation syndrome. Seventeen cases of new-onset or relapse of AOSD following COVID-19 vaccination, including 14 identified in the literature review and our 3 patients, were all treated successfully with glucocorticoid therapy, immunosuppressive drugs, or biologic agents.

Abatacept ameliorates both glandular and extraglandular involvements in patients with Sjögren's syndrome associated with rheumatoid arthritis: Findings from an open-label, multicentre, 1-year, prospective study: The ROSE (Rheumatoid Arthritis with Orencia Trial Toward Sjögren's Syndrome Endocrinopathy) and ROSE II trials.

OBJECTIVE: To clarify the efficacy and safety of intravenous abatacept for glandular and extraglandular involvements in Sjögren's syndrome (SS) associated with rheumatoid arthritis (RA). MATERIALS AND METHODS: We performed an open-label, prospective, 1-year, observational multicenter study (ROSE and ROSE II trials). The primary endpoint was the remission rate as measured by SDAI at 52 weeks. The secondary endpoints included the changes in the Saxon's test, Schirmer's test, ESSDAI and ESSPRI. Adverse events and adherence rates were also analyzed. RESULTS: 68 patients (36 in ROSE and 32 in ROSE II, all women) were enrolled. SDAI decreased significantly from 23.6 ± 13.2 at baseline to 9.9 ± 9.5 at 52 weeks. Patients with SDAI remission increased from 0 (0 weeks) to 19 patients (27.9%) at 52 weeks. Saliva volume increased significantly at 24 weeks. Tear volume increased significantly at 52 weeks. Both ESSDAI and ESSPRI were significantly decreased at 12 weeks, and these responses were maintained up to 52 weeks. The rate of adherence to abatacept over the 52-week period was 83.8%. Twenty-two adverse events occurred in 15 patients. CONCLUSION: Abatacept ameliorated both glandular and extraglandular involvements, as well as the systemic disease activities and patient-reported outcomes based on composite measures, in SS associated with RA.

Encapsulating Peritoneal Sclerosis in Systemic Lupus Erythematosus, Rheumatoid Arthritis, and Systemic Sclerosis.

We encountered a 57-year-old Japanese woman with encapsulating peritoneal sclerosis (EPS) in systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and systemic sclerosis. The patient was admitted to our hospital because of ascites retention. Administration of tocilizumab, an anti-interleukin-6 receptor antibody, for her RA reduced the refractory ascites remarkably; however, she developed sudden acute gastrointestinal bleeding and died a year later. On autopsy, sclerotic thickening of the peritoneum showed diffuse infiltration of podoplanin-positive fibroblast-like cells, and a diagnosis of EPS was made. EPS rarely occurs in SLE, and tocilizumab may be a new treatment candidate for EPS.

Evaluation of anti-severe acute respiratory syndrome coronavirus 2 antibody levels in coronavirus disease breakthrough infection during immunosuppressive therapy in a patient with connective tissue disease-related interstitial lung disease.

Herein, we report the case of a 67-year-old man with severe coronavirus disease (COVID-19) pneumonia and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine breakthrough infection during immunosuppressive therapy for connective tissue disease-related interstitial lung disease (CTD-ILD). The patient received glucocorticoids combined with tacrolimus as maintenance therapy. His serum anti-SARS-CoV-2-immunoglobulin G (IgG) antibody levels were extremely low at the onset of COVID-19 pneumonia, even after the second dose of SARS-CoV-2 mRNA vaccine (BNT162b2). After treatment for COVID-19 pneumonia, the levels of anti-SARS-CoV-2-IgG antibodies increased. These results indicated a lack of the ability to produce neutralising antibodies from immune cells despite the booster vaccination. Therefore, we suggest that advanced-age patients with CTD-ILD receiving immunosuppressive therapy with polypharmacy require consistent personal protection, vaccination of close caregivers, increased awareness, and booster vaccination. Moreover, we recommend that tacrolimus should be withdrawn for a while after vaccination under controlled conditions.

Transition from epoprostenol to selexipag in a patient with systemic sclerosis and pulmonary hypertension during the postoperative period of colon cancer surgery: A case report.

Introduction: Most pulmonary vasodilators are administered orally; however, in patients with pulmonary hypertension undergoing gastrointestinal surgery, a switch to parenteral drugs is needed. Parenteral pulmonary vasodilators carry a risk of infection and reduced quality of life owing to long-term central venous catheterization; therefore, it is preferable to switch them to oral vasodilators after surgery. Here, we present the case of a patient with systemic sclerosis complicated by pulmonary hypertension and colon cancer, for which treatment was successfully switched from epoprostenol to selexipag postoperatively. Case Description: A 59-year-old woman, who was diagnosed with mixed group I and III pulmonary hypertension and systemic sclerosis, was on oral triple pulmonary vasodilators for pulmonary hypertension and Raynaud's phenomenon. She was diagnosed as having colon cancer 3 months before admission. Despite the severe pulmonary condition and treatment with oral triple pulmonary vasodilators, colon cancer resection surgery was performed with the management for pulmonary hypertension through multidisciplinary treatments in collaboration with cardiology specialists. Medications for patients with pulmonary hypertension undergoing gastrointestinal surgery need to be switched from oral vasodilators to epoprostenol perioperatively. On postoperative day 19, 0.4 mg/day of selexipag was administered with epoprostenol. Subsequently, the epoprostenol dosage was gradually decreased, and selexipag was increased. On postoperative day 30, the dose of selexipag was increased to 1.2 mg/day and epoprostenol was discontinued. The patient was discharged on postoperative day 40. Conclusion: In our case, transition from epoprostenol to selexipag contributed to a more useful management strategy for systemic sclerosis and pulmonary hypertension in the postoperative period.

Induction of memory-like CD8+ T cells and CD4+ T cells from human naive T cells in culture.

Memory T cells are crucial players in vertebrate adaptive immunity but their development is incompletely understood. Here, we describe a method to produce human memory-like T cells from naive human T cells in culture. Using commercially available human T-cell differentiation kits, both purified naive CD8+ T cells and purified naive CD4+ T cells were activated via T-cell receptor signaling and appropriate cytokines for several days in culture. All the T-cell activators were then removed from the medium and the cultures were continued in hypoxic condition (1% O2 atmosphere) for several more days; during this period, most of the cells died, but some survived in a quiescent state for a month. The survivors had small round cell bodies, expressed differentiation markers characteristic of memory T cells and restarted proliferation when the T-cell activators were added back. We could also induce memory-like T cells from naive human T cells without hypoxia, if we froze the activated T cells or prepared the naive T cells from chilled filter buffy coats.

Improvement in Glucocorticoid-Induced Osteoporosis on Switching from Bisphosphonates to Once-Weekly Teriparatide: A Randomized Open-Label Trial.

This randomized, open-label, multicenter, parallel study imitating real-world clinical practice assessed the effect of switching to weekly teriparatide in patients with glucocorticoid-induced osteoporosis (GIO) with a lumbar spine/proximal femur bone mineral density (BMD) T-score ≤ -2.0 or ≤-1.0 and a fragility fracture. Forty-four patients were randomized. The mean durations of the corticosteroid and bisphosphonate administrations were 90.0 and 51.3 months. The baseline BMD at L1-L4 was 0.828 and 0.826 g/cm2 in Groups B (bisphosphonate) and T (teriparatide); at the femur (total), these values were 0.689 and 0.661 g/cm2. The mean change in BMD was numerically higher with teriparatide vs. bisphosphonate but not statistically significant. The mean percentage changes from baseline in BMD at L1-L4 after a 72-week treatment were 0.5% and 4.1% in Groups B and T. The incidence of new fractures was higher in the patients taking bisphosphonates vs. those receiving once-weekly teriparatide at 72 weeks (18.2% vs. 11.8%) and 144 weeks (22.7% vs. 17.6%). The mean percentage change in femur (trochanter) BMD (0.035 [0.007-0.063]; p = 0.02) was significantly greater with teriparatide vs. bisphosphonates. Adverse events (AEs) were more frequent with teriparatide vs. bisphosphonates. Switching to once-weekly teriparatide tended to increase lumbar spine BMD and reduce the occurrence of new fractures vs. bisphosphonates.

Dual effects of interleukin-10 on natural killer cells and monocytes and the implications for adult-onset Still's disease.

OBJECTIVES: We compared the serum levels of multiple cytokines in patients with adult-onset Still's disease (AOSD) and healthy controls to assess the effects of humoral factors on natural killer (NK) cells and monocytes. METHODS: We quantified the serum levels of 10 cytokines in the patients using bead-based multiplex immunoassays, along with interleukin (IL-)18 using ELISA. We then sorted NK cells and monocytes from the peripheral blood mononuclear cells (PBMCs) of healthy volunteers, cultured them in the presence or absence of cytokines that were detected in some or all of the serum samples from the AOSD patients and their combinations in vitro, and analysed the culture supernatant. RESULTS: IL-6 and IL-18 were the main cytokines increased in the serum of AOSD patients. When NK cells were cultured with the cytokines and IL-10, the combination of IL-10 and IL-18 substantially induced interferon (IFN-)γ. IL-6 had little effect on NK cells, probably because they barely expressed the IL-6 receptor and glycoprotein 130 (gp130). IFN-γ induced monocytes to produce IL-1ß, IL-6 and tumour necrosis factor (TNF-)α whereas IL-10 inhibited the induction of these proinflammatory cytokines. CONCLUSIONS: IL-10 evidently has dual effects on NK cells (stimulation) and on monocytes (inhibition). Better understanding the roles of the cytokine network would shed light on the pathogenesis of AOSD.

Texture analysis of muscle MRI: machine learning-based classifications in idiopathic inflammatory myopathies.

To develop a machine learning (ML) model that predicts disease groups or autoantibodies in patients with idiopathic inflammatory myopathies (IIMs) using muscle MRI radiomics features. Twenty-two patients with dermatomyositis (DM), 14 with amyopathic dermatomyositis (ADM), 19 with polymyositis (PM) and 19 with non-IIM were enrolled. Using 2D manual segmentation, 93 original features as well as 93 local binary pattern (LBP) features were extracted from MRI (short-tau inversion recovery [STIR] imaging) of proximal limb muscles. To construct and compare ML models that predict disease groups using each set of features, dimensional reductions were performed using a reproducibility analysis by inter-reader and intra-reader correlation coefficients, collinearity analysis, and the sequential feature selection (SFS) algorithm. Models were created using the linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), support vector machine (SVM), k-nearest neighbors (k-NN), random forest (RF) and multi-layer perceptron (MLP) classifiers, and validated using tenfold cross-validation repeated 100 times. We also investigated whether it was possible to construct models predicting autoantibody status. Our ML-based MRI radiomics models showed the potential to distinguish between PM, DM, and ADM. Models using LBP features provided better results, with macro-average AUC values of 0.767 and 0.714, accuracy of 61.2 and 61.4%, and macro-average recall of 61.9 and 59.8%, in the LDA and k-NN classifiers, respectively. In contrast, the accuracies of radiomics models distinguishing between non-IIM and IIM disease groups were low. A subgroup analysis showed that classification models for anti-Jo-1 and anti-ARS antibodies provided AUC values of 0.646-0.853 and 0.692-0.792, with accuracy of 71.5-81.0 and 65.8-78.3%, respectively. ML-based TA of muscle MRI may be used to predict disease groups or the autoantibody status in patients with IIM and is useful in non-invasive assessments of disease mechanisms.

Clinical features resembling subcutaneous insulin resistance observed in a patient with type 2 diabetes and severe COVID-19-associated pneumonia: a case report.

We report the case of a 52-year-old hyperglycemic woman with type 2 diabetes and severe coronavirus disease 2019 (COVID-19)-associated pneumonia, possibly involving the subcutaneous insulin resistance (SIR) syndrome. After admission for pneumonia, her average daily blood glucose (BG) levels remained at 300-400 mg/dL, although the required dosage of subcutaneous insulin markedly increased (~ 150 units/day; ~ 2.63 units/kg/day). Furthermore, the patient had generalized edema along with hypoalbuminemia, developed extensive abdominal purpuras, and had increased plasma D-dimer levels during treatment, suggestive of coagulation abnormalities. Therefore, intravenous infusion of regular insulin was initiated. The BG level subsequently decreased to < 200 mg/dL 2 days after administering 18 units/day of insulin infusion and 118 units/day of subcutaneous insulin, suggesting that subcutaneous insulin alone might have been ineffective in reducing hyperglycemia, which is clinically consistent with the characteristics of an SIR syndrome. Impaired skin microcirculation arising from coagulation abnormalities, subcutaneous edema associated with inflammation-related hypoalbuminemia or vascular hyperpermeability, and/or reduction in subcutaneous blood flow due to COVID-19-induced downregulation of angiotensin-converting enzyme 2 might be associated with the development of pathological conditions that resemble SIR syndrome, leading to impaired subcutaneous insulin absorption. Supplementary Information: The online version contains supplementary material available at 10.1007/s13340-021-00500-x.

Characterization and Function of Tumor Necrosis Factor and Interleukin-6-Induced Osteoclasts in Rheumatoid Arthritis.

OBJECTIVE: We have previously reported that stimulation of mouse bone marrow-derived macrophages with tumor necrosis factor (TNF) and interleukin-6 (IL-6) induces differentiation of osteoclast-like cells. We undertook this study to clarify the characterization and function of human TNF and IL-6-induced osteoclasts using peripheral blood collected from patients with rheumatoid arthritis (RA) and healthy donors. METHODS: Peripheral blood monocytes were cultured with a combination of TNF and IL-6, TNF alone, IL-6 alone, or with RANKL, and their bone resorption ability was evaluated. Expression levels of NFATc1, proinflammatory cytokines, and matrix metalloproteinase 3 were analyzed. The effects of NFAT inhibitor and JAK inhibitor were examined. Furthermore, the relationship between the number of TNF and IL-6-induced osteoclasts or RANKL-induced osteoclasts differentiated from peripheral blood mononuclear cells (PBMCs) in patients with RA and the modified total Sharp score (mTSS) or whole-body bone mineral density (BMD) was examined. RESULTS: Peripheral blood monocytes stimulated with a TNF and IL-6-induced osteoclasts were shown to demonstrate the ability to absorb bone matrix. Cell differentiation was not inhibited by the addition of osteoprotegerin. Stimulation with a combination of TNF and IL-6 promoted NFATc1 expression, whereas the NFAT and JAK inhibitors prevented TNF and IL-6-induced osteoclast formation. Expression levels of IL1ß, TNF, IL12p40, and MMP3 were significantly increased in TNF and IL-6-induced osteoclasts, but not in RANKL-induced osteoclasts. The number of TNF and IL-6-induced osteoclasts differentiated from PBMCs in patients with RA positively correlated with the mTSS, whereas RANKL-induced osteoclast numbers negatively correlated with the whole-body BMD of the same patients. CONCLUSION: Our results demonstrate that TNF and IL-6-induced osteoclasts may contribute to the pathology of inflammatory arthritis associated with joint destruction, such as RA.

Treatment of psoriatic arthritis complicated by systemic lupus erythematosus with the IL-17 blocker secukinumab and an analysis of the serum cytokine profile.

Psoriasis is a chronic disease of the skin that often affects the joints (psoriatic arthritis, PsA). Biologic agents such as TNF-α, IL-23 and IL-17 blockers have been proven to be quite effective against psoriasis and PsA, indicating the importance of those cytokines in the pathogenesis of the diseases. The importance of the IL-23/IL-17 axis has also been reported in systemic lupus erythematosus (SLE), but the safety and effectiveness of IL-17 blockers in SLE remain largely unknown. We encountered a patient with PsA and SLE. We treated him with an IL-17 blocker, secukinumab, and quantified the serum levels of various cytokines before and after the initiation of secukinumab therapy. As expected, the treatment was effective against the symptoms of PsA. No serious adverse events were observed in terms of SLE. Interestingly, serum IL-6 was substantially decreased after the initiation of therapy, whereas serum IL-17 was under the detection limit. These data indicate that IL-17 is produced locally, upstream of IL-6 production.