Anti-TRIM21 antibody is associated with aberrant B-cell function and type I interferon production in systemic lupus erythematosus.

BACKGROUND: TRIM21 is a member of the tripartite motif family proteins and is one of the autoantigens which react with anti-SS-A antibody (Ab) present in sera of patients with systemic lupus erythematosus (SLE) and Sjögren's syndrome. Previous studies have shown that TRIM21 dysfunction promotes aberrant B-cell differentiation and Ab production in SLE, and anti-TRIM21 Ab may be related to the TRIM21 dysfunction in human SLE pathogenesis. Here, we examined the relationship between anti-TRIM21 Ab and clinical and immunological characteristics in SLE patients. METHODS: Twenty-seven patients with SLE (23 women and four men) before immunosuppressive therapies, who fulfilled the revised 1997 American College of Rheumatology criteria for SLE, and four healthy controls (3 women and one man) were enrolled in the study. SLE patients were divided into two groups according to the seropositivity for anti-TRIM21 Ab. Serum anti-TRIM21 Ab levels were measured using enzyme-linked immunosorbent assays. The serum levels of cytokines and immunoglobulins were measured by cytometer beads arrays. The expression levels of TRIM21 protein in peripheral mononuclear cells (PBMCs) from SLE patients were evaluated by Western blotting. RESULTS: Sixteen and 9 patients showed seronegativity and seropositivity for anti-TRIM21 Ab, respectively. There were no significant differences in the background parameters, including female ratio, age, disease duration, SLE activity, and laboratory data between the two groups. The serum levels of interferon (IFN)-ß were significantly higher in patients with anti-TRIM21 Ab as compared with those without anti-TRIM21 Ab (P = .043). The levels of IgG1 and IgA were significantly higher in SLE patients with anti-TRIM21 Ab as compared with those without anti-TRIM21 Ab (P = .0022 and .032, respectively). The PBMCs of patients with anti-TRIM21 Ab showed a significantly lower expression of TRIM21 protein as compared with those of patients without anti-TRIM21 Ab (P = .014). CONCLUSIONS: Anti-TRIM21 Ab seropositivity was related to B-cell abnormalities and type I IFN overproduction in SLE patients. These findings suggest that anti-TRIM21 Ab may have an inhibitory effect on TRIM21 functions and be a novel biomarker for the level of dependence on type I IFN overproduction and B-cell abnormalities.

miR-1 is a novel biomarker for polymyositis/dermatomyositis-associated interstitial lung disease.

Objectives: Although intensive immunosuppressive treatment is necessary for the severe cases with polymyositis (PM)/dermatomyositis (DM), the prognostic factors or disease activity indices for PM/DM have not been established. Here we investigated the association between serum microRNA-1 (miR-1) level and clinical course of patients with PM/DM.Methods: We retrospectively reviewed baseline clinical and laboratory findings, treatment regimens and outcomes in patients with PM/DM. The serum samples were collected from PM/DM patients and healthy controls (HC). Serum miR-1 levels were determined by quantitative real-time PCR.Results: Twenty-two patients were recruited. The average serum miR-1 level was significantly higher in the PM/DM as compared to HC (p = .0085) and was decreased by treatment (p = .032). We divided the PM/DM-ILD patients into two groups, high and normal miR-1 groups. Although there were no significant differences in the clinical data and the initial prednisolone (PSL) dose between the two groups, PSL dose at 16 weeks, cumulative PSL dose until 16 weeks, and frequency of serious infections were significantly higher in the high miR-1 group as compared to the normal group (p = .025, .036, and .026, respectively).Conclusion: We propose serum miR-1 as a promising novel biomarker for predicting therapeutic response in PM/DM-ILD.

Dysfunction of TRIM21 in interferon signature of systemic lupus erythematosus.

OBJECTIVES: TRIM21 is an E3 ubiquitin ligase for interferon regulatory factors (IRFs) that are involved in innate and acquired immunity. Here, we evaluated the role of TRIM21 in the interferon (IFN) signature of systemic lupus erythematosus (SLE). METHODS: Twenty SLE patients and 24 healthy controls were enrolled in this study. We analyzed mRNA expression of TRIM21, type I IFN, and IFN-inducible genes in peripheral blood mononuclear cell (PBMC). The protein levels of IRFs were assessed by Western blotting in PBMCs cultured with or without MG-132. RESULTS: The expression of TRIM21 mRNA and protein was significantly higher in SLE PBMCs as compared to healthy controls. There was a correlation between TRIM21 mRNA expression and SLE activities. In contrast to a negative correlation between mRNA expression level of TRIM21 and those of type I IFNs in healthy controls, we found a positive correlation between them in anti-TRIM21 antibody-positive SLE patients. Neither positive nor negative correlation was observed in the autoantibody-negative SLE patients. Western-blotting analysis revealed impaired ubiquitin-dependent proteasomal degradation of IRFs in SLE PBMCs. CONCLUSION: Our study showed ubiquitin-dependent proteasomal degradation of IRFs was impaired in anti-TRIM21 antibody-dependent and -independent fashions, leading to amplification of IFN signature in SLE.

Musculoskeletal ultrasonography delineates ankle symptoms in rheumatoid arthritis.

OBJECTIVES: To clarify the use of musculoskeletal ultrasonography (US) of ankle joints in rheumatoid arthritis (RA). METHODS: Consecutive RA patients with or without ankle symptoms participated in the study. The US, clinical examination (CE), and patients' visual analog scale for pain (pVAS) for ankles were assessed. Prevalence of tibiotalar joint synovitis and tenosynovitis were assessed by grayscale (GS) and power Doppler (PD) US using a semi-quantitative grading (0-3). The positive US and CE findings were defined as GS score ≥2 and/or PD score ≥1, and joint swelling and/or tenderness, respectively. Multivariate analysis with the generalized linear mixed model was performed by assigning ankle pVAS as a dependent variable. RESULTS: Among a total of 120 ankles from 60 RA patients, positive ankle US findings were found in 21 (35.0%) patients. The concordance rate of CE and US was moderate (kappa 0.57). Of the 88 CE negative ankles, US detected positive findings in 9 (10.2%) joints. Multivariate analysis revealed that ankle US, clinical disease activity index, and foot Health Assessment Questionnaire, but not CE, was independently associated with ankle pVAS. CONCLUSION: US examination is useful to illustrate RA ankle involvement, especially for patients who complain ankle pain but lack CE findings.

On-demand ultrasonography assessment in the most symptomatic joint supports the 8-joint score system for management of rheumatoid arthritis patients.

OBJECTIVES: To investigate whether on-demand ultrasonography (US) assessment alongside a routine examination is useful in the management of rheumatoid arthritis (RA). METHODS: US was performed in eight (bilateral MCP 2, 3, wrist and knee) joints as the routine in a cumulative total of 406 RA patients. The most symptomatic joint other than the routine joints was additionally scanned. Power Doppler (PD) and gray-scale images were scored semiquantitatively. Eight-joint scores were calculated as the sum of individual scores for the routine joints. RESULTS: The most symptomatic joint was found among the routine joints in 209 patients (Group A) and in other joints in 148 (Group B). The PD scores of the most symptomatic joint correlated well with the 8-joint scores in Group A (rs = 0.66), but not in Group B (rs = 0.33). The sensitivity and specificity of assessment of the most symptomatic joint for routine assessment positivity were high (84.0% and 100%, respectively) in Group A, but low (50.0% and 61.8%, respectively) in Group B. Additional examination detected synovitis in 38% of Group B with negative results in the routine. CONCLUSIONS: On-demand US assessment in the most symptomatic joint, combined with the routine assessment, is useful for detecting RA synovitis.

Incidence and Distinct Features of Immune Checkpoint Inhibitor-Related Myositis From Idiopathic Inflammatory Myositis: A Single-Center Experience With Systematic Literature Review and Meta-Analysis.

Immune checkpoint inhibitor (ICI)-related myositis is a rare, potentially fatal condition that warrants further studies. Its incidence, clinical features, and prognosis remain poorly understood. To address these gaps, we conducted a systematic review and meta-analysis to evaluate the risk of myositis associated with ICI for solid tumors by analyzing phase III randomized controlled trials of anti-programmed death-1/ligand-1 (PD-1/PD-L1) and anti-cytotoxic T-lymphocyte antigen-4 (CTLA-4). To complement this analysis with clinical data, we evaluated published ICI case reports along with cases from our institutional registry. This registry comprised 422 patients treated with ICIs alone or in combination from September 2014 to June 2021. The analysis revealed an incidence of ICI-related myositis in 6,838 patients in 18 randomized controlled trials of 0.38% (odds ratio 1.96; 95% confidence interval 1.02-3.75) for patients receiving ICIs compared with controls. Detailed analysis of 88 cases from the literature search and our registry showed that myositis induced by PD-1 inhibitors was more frequent than that induced by anti-CTLA-4 agents, revealing a clinically diverse trend including myasthenia gravis and myocarditis. Importantly, having ptosis at the time of onset was significantly associated with the development of concomitant myocarditis (odds ratio 3.81; 95% CI 1.48-9.83), which is associated with poor prognosis. Regarding treatment, most patients received glucocorticoids, and some received immunosuppressants. Our study revealed the incidence of ICI-mediated myositis and the clinical features of myocarditis, highlighting the need for recognition and early intervention.

Changes in the proportion of clinical clusters contribute to the phenotypic evolution of Behçet's disease in Japan.

BACKGROUND: We hypothesized that Behçet's disease (BD) consists of several clinical subtypes with different severity, resulting in heterogeneity of the disease. Here, we conducted a study to identify clinical clusters of BD. METHODS: A total of 657 patients registered in the Yokohama City University (YCU) regional BD registry between 1990 and 2018, as well as 6754 patients who were initially registered in the Japanese Ministry of Health, Labour and Welfare (MHLW) database between 2003 and 2014, were investigated. The YCU registry data regarding the clinical manifestations of BD, human leukocyte antigen (HLA) status, treatments, and hospitalizations were analyzed first, followed by similar analyses of the MHLW for validation. A hierarchical cluster analysis was independently performed in both patient groups. RESULTS: A hierarchical cluster analysis determined five independent clinical clusters in the YCU cohort. Individual counterparts of the YCU clusters were confirmed in the MHLW registry. Recent phenotypical evolutions of BD in Japan, such as increased gastrointestinal (GI) involvement, reduced complete type according to the Japan Criteria, and reduced HLA-B51 positivity were associated with chronologically changing proportions of the clinical clusters. CONCLUSIONS: In this study, we identified independent clinical clusters among BD patients in Japan and found that the proportion of each cluster varied over time. We propose five independent clusters namely "mucocutaneous", "mucocutaneous with arthritis", "neuro", "GI", and "eye."

Risk Prediction Modeling Based on a Combination of Initial Serum Biomarker Levels in Polymyositis/Dermatomyositis-Associated Interstitial Lung Disease.

OBJECTIVE: To establish predictive models for mortality in patients with polymyositis/dermatomyositis-associated interstitial lung disease (PM/DM-ILD) using a combination of initial serum biomarker levels. METHODS: The Multicenter Retrospective Cohort of Japanese Patients with Myositis-Associated ILD (JAMI) database of 497 incident cases of PM/DM-ILD was used as a derivation cohort, and 111 cases were additionally collected as a validation cohort. Risk factors predictive of all-cause mortality were identified by univariate and multivariable Cox regression analyses using candidate serum biomarkers as explanatory variables. The predictive models for mortality were generated in patients with and those without anti-melanoma differentiation-associated gene 5 (MDA-5) antibody, using a combination of risk factors. Cumulative survival rates were assessed using Kaplan-Meier analysis, and were compared between subgroups using the Breslow test. RESULTS: In the derivation cohort, C-reactive protein (CRP) and Krebs von den Lungen 6 (KL-6) levels were identified as independent risk factors for mortality in both anti-MDA-5-positive and anti-MDA-5-negative patients. We then developed a prediction model based on anti-MDA-5 antibody status, CRP level, and KL-6 level, termed the "MCK model," to identify patients at low (<15%), moderate (15-50%), or high (≥50%) risk of mortality, based on the number of risk factors. The MCK model successfully differentiated cumulative survival rates in anti-MDA-5-positive patients (P < 0.01 for low versus moderate risk and P = 0.03 for moderate versus high risk) and in anti-MDA-5-negative patients (P < 0.001 for low versus moderate risk). The utility of the MCK model was replicated in the validation cohort. CONCLUSION: Our findings indicate that an evidence-based risk prediction model using CRP and KL-6 levels combined with anti-MDA-5 antibody status might be useful for predicting prognosis in patients with PM/DM-ILD.

TRIM21 Dysfunction Enhances Aberrant B-Cell Differentiation in Autoimmune Pathogenesis.

TRIM21 is one of the autoantigens that reacts with an anti-SS-A antibody (Ab) present in patients with systemic lupus erythematosus (SLE) and Sjögren's syndrome. TRIM21 is thought to play a role in B-cell proliferation and apoptosis, among other activities. Here we examined a pathological role of TRIM21 in SLE. Trim21-deficient MRL/lpr mice were generated by backcrossing Trim21-deficient C57BL/6 mice to MRL/lpr mice. The levels of serum anti-dsDNA Ab and urine protein at 28 weeks of age were significantly higher in Trim21-deficient MRL/lpr mice as compared to wild-type MRL/lpr mice (p = 0.029 and 0.003, respectively). Resting B cells from Trim21-deficient mice showed significantly higher abilities to differentiate into plasmablasts and to produce Ab as compared with control mice. Due to the reduction of TRIM21-mediated ubiquitylation, IRF5 protein expression was increased in Trim21-deficient MRL/lpr mice (p = 0.021), which correlated with increased plasmablast generation and immunoglobulin production. B cells from SLE patients with anti-TRIM21 Ab seropositivity also showed a significantly higher ability to differentiate into plasmablasts as compared with those without anti-TRIM21 Ab or healthy controls. These results suggest that TRIM21 dysfunction contributes to SLE pathogenesis by promoting B-cell differentiation, for which anti-TRIM21 Ab may be partly responsible.

Synthetic approach to telomerase inhibitor dictyodendrin B: synthesis of the pyrrolo[2,3-c]carbazole core.

The core structure of the telomerase inhibitor, dictyodendrin B, was synthesized by using the palladium-catalyzed cross-coupling reaction of 3-aryl-1-(2-arylethyl)-4-hydroxy-2,5-bismethoxycarbonylpyrrole triflate with 7-alkoxyindole-3-boronate as the key step.

Dose down-titration of biological disease-modifying antirheumatic drugs in daily clinical practice: Shared decision-making and patient treatment preferences in Japanese patients with rheumatoid arthritis.

AIM: To determine characteristics of rheumatoid arthritis (RA) patients in Japan who received the same biological disease-modifying antirheumatic drugs (bDMARDs) for at least 6 months and to identify factors associated with successful down-titration of bDMARDs dependent on shared decision-making. METHODS: We included consecutive RA patients who received the same bDMARD with low disease activity or remission for at least 6 months in our two university hospitals. Patients treated with the bDMARD standard dose were defined as SD, while those treated with bDMARD down-titration were defined as DT. We retrospectively reviewed clinical charts and compared data between the two groups. RESULTS: Of 288 patients with RA, 204 (70.8%) and 84 (29.2%) continued standard dose treatment and underwent down-titration treatment, respectively. Sixty-six of 84 (78.6%) down-titration-treated patients continued to show low disease activity or remission, whereas 18 (21.4%) relapsed 18.9 ± 24.4 months after bDMARD down-titration was started. Univariate predictor analysis showed that the probable factors of down-titration were no history of bDMARD treatment (P = .001) and low initial Disease Activity Assessment of 28 joint score (P = .048). Other clinical characteristics had no significant relationship with successful down-titration. CONCLUSIONS: Thus, bDMARD-naïve patients and those with low initial disease activity are more likely to agree to attempt down-titration. However, the timing and method of down-titration should be made in shared decision-making between patients and rheumatologists.

The predictive prognostic factors for polymyositis/dermatomyositis-associated interstitial lung disease.

BACKGROUND: Interstitial lung disease (ILD) is the principal cause of death in polymyositis/dermatomyositis (PM/DM). Here we investigated prognostic factors for death and serious infection in PM/DM-ILD using the multicenter database. METHODS: We retrospectively reviewed baseline demographic, clinical and laboratory findings, treatment regimens and outcomes in patients with PM/DM-ILD. The distribution of ILD lesions was evaluated in four divided lung zones of high-resolution computed tomography images. RESULTS: Of 116 patients with PM/DM-ILD, 14 died within 6 months from the diagnosis. As independent risk factors for early death, extended ILD lesions in upper lung fields (odds ratio (OR) 8.01, p = 0.016) and hypocapnia (OR 6.85, p = 0.038) were identified. Serious infection was found in 38 patients, including 11 patients who died of respiratory or multiple infections. The independent risk factors were high serum KL-6 (OR 3.68, p = 0.027), high initial dose of prednisolone (PSL) (OR 4.18, p = 0.013), and combination immunosuppressive therapies (OR 5.51, p < 0.001). CONCLUSION: The present study shows the progression of ILD at baseline is the most critical for survival and that infection, especially respiratory infection, is an additive prognostic factor under the potent immunosuppressive treatment.

Non-IgG4-related Multifocal Fibrosclerosis.

Multifocal fibrosclerosis (MFS), which causes systemic and chronic connective tissue inflammation, has been associated with IgG4 and regarded as an identical entity with "IgG4-related disease (IgG4-RD)". Although a few cases of MFS mimicking IgG4-RD histopathologically, despite the absence of a serum IgG4 elevation and IgG4-positive plasma cell infiltration, have been reported, there is, so far, little information regarding such exceptional cases. We herein demonstrate a case of non-IgG4-related MFS presenting with periaortitis and parotiditis, whose histological findings were consistent with IgG4-RD despite the absence of elevated serum and tissue IgG4 levels.