Critical role of lectin pathway mediated by MBL-associated serine proteases in complement activation for the pathogenesis in systemic lupus erythematosus.

In complement activation system, although the classical pathway has shown to play a critical role for the pathogenesis of SLE, the role of lectin pathway has remained unknown in the pathogenesis of SLE. As Mannose-binding lectin-associated serine proteases (MASPs) are associated with activation of the lectin pathway, we conducted this study to clarify MASPs associations in the pathogenesis of SLE. We evaluated the serum level of MASPs (MASP-1 and MASP-2) in total 68 SLE patients consisting of 15 patients with biopsy-confirmed membranous lupus nephritis (M-LN), 35 patients with biopsy-confirmed proliferative lupus nephritis (P-LN), and 18 SLE patients without LN (non-LN). Our data showed that the serum levels of MASPs were reduced in both P-LN and non-LN although those of M-LN were not reduced. Our data show that the lectin pathway mediated by MASPs plays a critical role for the pathogenesis of SLE except for M-LN.

Transitions in vascular ultrasonography findings of temporal arteritis in a GCA case with progressive temporal headache and visual impairment.

The European League Against Rheumatism and the American College of Rheumatology have stated that the halo sign on vascular ultrasonography (v-US) is relevant in diagnosing giant cell arteritis (GCA) and is equivalent to temporal artery biopsy. However, there are only a few reports about transitions in v-US findings after glucocorticoid (GC) therapy. We report the transitions in the v-US findings in a case of GCA after GC therapy. The patient had rapidly progressive symptoms, and there were concerns about blindness. After GC therapy, we first observed improvement in headache and visual impairment symptoms within 1 week, followed by rapid improvement in laboratory findings within 2 weeks. Subsequently, there were improvements in v-US findings after more than 2 months. In conclusion, these findings showed a dissociation between improvements in clinical symptoms and v-US findings of the temporal artery. Additionally, this case suggests that regular examination of v-US findings is useful in evaluating GCA with evident vascular wall thickness before GC therapy.

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.

Periostin-related progression of different types of experimental pulmonary hypertension: A role for M2 macrophage and FGF-2 signalling.

BACKGROUND AND OBJECTIVE: Remodelling of pulmonary arteries (PA) contributes to the progression of pulmonary hypertension (PH). Periostin, a matricellular protein, has been reported to be involved in the development of PH. We examined the role of periostin in the pathogenesis of PH using different types of experimental PH. METHODS: PH was induced by vascular endothelial growth factor receptor antagonist (Sugen5416) plus hypoxic exposure (SuHx) and venous injection of monocrotaline-pyrrole (MCT-P) in wild-type (WT) and periostin-/- mice. Pulmonary haemodynamics, PA remodelling, expression of chemokines and fibroblast growth factor (FGF)-2, accumulation of macrophages to small PA and the right ventricle (RV) were examined in PH-induced WT and periostin-/- mice. Additionally, the role of periostin in the migration of macrophages, human PA smooth muscle (HPASMCs) and endothelial cells (HPMVECs) was investigated. RESULTS: In PH induced by SuHx and MCT-P, PH and accumulation of M2 macrophage to small PA were attenuated in periostin-/- mice. PA remodelling post-SuHx treatment was also mild in periostin-/- mice compared to WT mice. Expression of macrophage-associated chemokines and FGF-2 in lung tissue, and accumulation of CD68-positive cells in the RV were less in SuHx periostin-/- than in SuHx WT mice. Periostin secretion in HPASMCs and HPMVECs was enhanced by transforming growth factor-ß. Periostin also augmented macrophage, HPASMCs and HPMVECs migration. Separately, serum periostin levels were significantly elevated in patients with PH compared to healthy controls. CONCLUSION: Periostin is involved in the development of different types of experimental PH, and may also contribute to the pathogenesis of human PH.

Effect of Prophylactic Dose of Trimethoprim-Sulfamethoxazole on Serum Creatinine in Japanese Patients With Connective Tissue Diseases.

Objectives: At normal doses of trimethoprim-sulfamethoxazole (TMP/SMX), trimethoprim inhibits tubular creatinine secretion, leading to a rapid but reversible increase in serum creatinine (SCr). Although patients with connective tissue diseases are often in the state of immunosuppression and TMP/SMX is an important prophylactic drug, clinicians often have to stop or reduce the dosage due to concerns regarding its effect on renal function. This study aimed to evaluate the effect of a prophylactic dose of TMP/SMX on SCr in Japanese patients with connective tissue diseases, the extent of SCr level elevation and the independent risk factors for creatinine elevation. Methods: A retrospective cohort study was undertaken. Participants included patients with connective tissue diseases who were treated with a prophylactic dose of TMP/SMX between 2004 and 2018. Using single and multiple regression analyses, the risk factors that affected SCr elevation were evaluated. Results: A total of 262 patients, females, n = 181; age, median (range) = 59 (19-89) years, were included. The median baseline SCr level before treatment was 0.62 (0.16-2.1) mg/dL. The median SCr elevation value was 0.07 (-0.54 to 0.84) mg/dL in 4 weeks after TMP/SMX initiation. Five (2%) participants had ⩾0.3 mg/dL SCr elevation. Multiple regression analyses, including age, baseline SCr, diuretic use, nonsteroidal anti-inflammatory drug use and diabetes mellitus, indicated that baseline SCr and advanced age were independent risk factors of SCr elevation. Conclusions: These results demonstrated that baseline SCr and advanced age were associated with SCr elevation by a prophylactic dose of TMP/SMX. However, a prophylactic dose of TMP/SMX rarely elevated the SCr level significantly. Therefore, other causes can be considered if patients show an SCr elevation ⩾0.3 mg/dL.

Application of gamma radiation for disinfection of fungi in a large volume of historical archives damaged by flood following Typhoon Hagibis 2019, Japan: A case report.

A large volume of historical archives was extensively damaged by flood water, following Typhoon Hagibis in Fukushima, Japan, in October 2019. They were rescued from the stricken area within a week, however, the prolonged exposure of paper documents to water caused severe biodegradation by fungal growth. To disinfect fungi, the paper documents were exposed to gamma radiations emitted by a source of Cobalt 60 by the industrial irradiation service. The wet paper documents were mainly contaminated with hydrophilic and cellulolytic fungi, including Trichoderma, Stachybotrys, and Fusarium; no fungi grew after irradiation. These results indicated that the average absorbed dosage from 13.1 kGy to 16.1 kGy were sufficient to disinfect paper documents heavily contaminated with fungi. In the present study, we demonstrated the successful practical use of irradiation in fungi-damaged paper documents using a commercial gamma-irradiation facility.

Diagnosis of giant cell arteritis by head-contrast three-dimensional computed tomography angiography: two case reports.

INTRODUCTION: Temporal artery biopsy is essential for the diagnosis of giant cell arteritis. It has been shown that 18F-fluorodeoxyglucose positron emission tomography-computed tomography, magnetic resonance angiography, and ultrasonography are useful for the diagnosis of giant cell arteritis. However, there are only a few reports on the usefulness of three-dimensional computed tomography angiography in the diagnosis of giant cell arteritis. We describe two cases in which giant cell arteritis was difficult to diagnose using positron emission tomography-computed tomography and magnetic resonance angiography but was diagnosed using three-dimensional computed tomography angiography, thus showing the importance of three-dimensional computed tomography angiography in the diagnosis of giant cell arteritis. CASE PRESENTATION: Case 1: An 81-year-old Japanese man. Laboratory investigations revealed normocytic anemia and raised inflammatory marker levels. Slight bleeding in the right posterior pole of his eyeball and leukoma of his left cornea were observed on fundus examination. Stenosis and stoppage of the temporal artery were detected on three-dimensional computed tomography angiography. A diagnosis of giant cell arteritis was made, and he was started on orally administered prednisolone. His headache and C-reactive protein levels improved. Four weeks after glucocorticoid steroid treatment, three-dimensional computed tomography angiography revealed improvement in stenosis and stoppage of temporal artery. Case 2: A 74-year-old Japanese woman. A dose of 20 mg of prednisolone was administered and her polymyalgia and polyarthritis improved; however, her headache and ear occlusion persisted. Although vasculitis was not detected on positron emission tomography-computed tomography, stenosis and stoppage of the temporal artery were detected on computed tomography angiography. She was diagnosed as having giant cell arteritis and started on orally administered prednisolone treatment (60 mg daily). Her headache and C-reactive protein levels improved. Four weeks after glucocorticoid treatment, three-dimensional computed tomography angiography showed improvement in stenosis and stoppage of temporal artery. CONCLUSIONS: In both patients with giant cell arteritis, three-dimensional computed tomography angiography revealed improvement in stenosis and stoppage of temporal artery after glucocorticoid treatment. We conclude that computed tomography angiography along with magnetic resonance angiography, positron emission tomography-computed tomography, and ultrasonography are important for the diagnosis of giant cell arteritis.

A case of ankylosing spondylitis with concurrent Takayasu arteritis.

We herein report a case involving a 56-year-old man who had experienced neck and lower back pain since the age of 23 years. Ankylosing spondylitis (AS) was diagnosed at 41 years of age, and treatment with sulfasalazine was initiated. At 44 years of age, the patient developed respiratory distress on exertion and chest pain. Aortic regurgitation (AR) was diagnosed via echocardiography, and the patient presented to our hospital for close examination and treatment. Coronary computed tomography angiography revealed no lesions in the coronary artery; however, magnetic resonance angiography revealed stenotic lesions in the left common carotid artery and left subclavian artery. Based on the findings of a physical examination, fundus examination, and blood tests, the patient was diagnosed with AS with concurrent Takayasu arteritis (TA). Upon administration of steroids to alleviate inflammation caused by an autoimmune mechanism, the patient's chest symptoms and inflammatory findings improved. AR was treated with aortic valve replacement and prosthetic blood vessel replacement, after which the patient progressed well. Intraoperative aortic biopsy revealed findings pathologically consistent with TA. Although AS with concurrent AR is well described, AS with concurrent TA, as in the present case, is rare.

Clinical characteristics and change in the antibody titres of patients with anti-MDA5 antibody-positive inflammatory myositis.

Objective: The aim of this study was to evaluate the clinical characteristics of patients with anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive inflammatory myositis, and the change in anti-MDA5 antibody titres before and after onset. Method: For 105 PM/DM patients, newly diagnosed in our hospital within the period 2008-2016, serum anti-MDA5 antibody levels were measured at diagnosis and after treatment by ELISA using the MESACUP anti-MDA5 test. The relationships between anti-MDA5 antibody levels and clinical manifestations, laboratory data, and mortality were examined. Result: Compared with patients who were anti-MDA5 antibody negative, those who were antibody positive demonstrated more frequent dermatitis, clinically amyopathic DM, interstitial lung disease and rapid-progressive interstitial lung disease, as well as significantly higher serum ferritin, significantly lower creatine kinase and aldolase, and significantly less frequent ANA (⩾1:160) and anti-cytoplasmic pattern of ANA staining positivity. Anti-MDA5 antibody titres were examined before disease onset in two patients; one showed antibody positivity with low titres 2 years earlier, while both exhibited increased titres at onset. Anti-MDA5 antibody titres declined significantly less in survivors than in non-survivors after treatment; however, there was no significant difference between the two groups when the rate was compared at 2 months after treatment. Conclusion: An initial decrease in anti-MDA5 antibody titre after commencement of treatment was observed in most of the patients, including in fatal cases, suggesting that this may not necessarily be a useful marker for treatment of patients with DM.

Elevated serum levels of soluble CD146 in patients with systemic sclerosis.

CD146, a transmembrane glycoprotein member of the immunoglobulin superfamily, acts as an adhesion molecule that helps maintain the cell monolayer. Human endothelial cells expressing CD146 are involved in angiogenesis and inflammation. Recently, we developed a sandwich ELISA for detecting soluble CD146 (sCD146) in human serum specimens. The aim of this study is to determine serum levels of sCD146 in patients with systemic sclerosis (SSc) and to examine the relationship between sCD146 levels and clinical manifestations. We quantified serum sCD146 levels in 47 serum samples from patients fulfilling criteria for SSc, 23 serum samples from patients fulfilling criteria for rheumatoid arthritis (RA), and 25 healthy controls. We also investigated the relationship between sCD146 levels and various clinical characteristics with SSc patients. Levels of sCD146 were significantly higher in the 47 patients with SSc than in the 25 healthy controls and 23 patients with RA (12.50 vs. 6.91 vs. 9.95 ng/ml; p < 0.001). Serum sCD146 levels in SSc patients with pulmonary arterial hypertension (PAH) were lower than in SSc patients without PAH (10.12 vs.13.17 ng/ml; p < 0.01). The serum levels of sCD146 were elevated in patients with SSc. However, decreased sCD146 levels were observed in SSc patients with PAH. Further studies are necessary to elucidate the sources and the mechanisms.

Recent trends in use of nonbiologic DMARDs and evaluation of their continuation rates in single and dual combination therapies in rheumatoid arthritis patients in Japan.

OBJECTIVE: We aim to examine changes in usage of nonbiologic, disease-modifying antirheumatic drugs (DMARDs) and evaluate their continuation rates in Japan. METHODS: We analyzed DMARD treatment data for 3,734 patients with rheumatoid arthritis (RA) from 1998 to 2009 at Juntendo Hospital in Tokyo, Japan. The DMARD usage rate per month was determined to evaluate RA treatment history in the last decade. We also evaluated continuation rates of nonbiologic DMARDs in single and combination therapies and number of nonbiologic DMARD combination therapies used in each patient. RESULTS: We found that nonbiologic DMARD usage has dramatically changed in the last decade, with the most commonly used DMARD shifting from bucillamine to methotrexate (MTX). MTX showed the highest continuation rate; however, much lower continuation rate was observed when used alone rather than in combination treatments. Further, MTX was also used in the highest number of different combination therapies for a particular patient. CONCLUSIONS: These findings indicate that single MTX treatment may be unable to keep patients in clinical remission or lower disease activity compared with several combination therapies. Recent change in permitted maximum dosage of MTX from 8 to 16 mg/week may improve its efficacy and continuation rate in treating Japanese RA patients.

Single-center, retrospective analysis of efficacy and safety of tacrolimus as a second-line DMARD in combination therapy and the risk factors contributing to adverse events in 115 patients with rheumatoid arthritis.

To retrospectively evaluate the efficacy and safety of combination therapy with tacrolimus (TAC) and other disease-modifying antirheumatic drugs (DMARDs). One hundred fifteen rheumatoid arthritis (RA) patients treated with tacrolimus were enrolled in this retrospective analysis. We collected clinical information, including patient background, treatment efficacy (evaluated using the DAS score), and adverse events observed. Multiple logistic regression analysis was conducted to analyze factors contributing to clinical response and adverse effects. The disease activity score of 28 joints (DAS28) improved significantly at 24 weeks, and continuation rate at 1 year was 57.9%. There was no difference in continuation rate between different DMARD combinations, and not only methotrexate (MTX) but also bucillamine (BUC) and salazosulfapyridine (SSZ) were effective combination partners with TAC. No serious adverse events were observed, and no different inefficacy or safety was observed between non-elderly (<65 years old) and elderly (≥65 years old) RA patients. By conducting multiple logistic regression analysis, combination therapy with MTX and TAC, the number of baseline DMARDs (specifically, ≥3), and old age were identified as risk factors for adverse events. Our findings indicate that TAC is a valuable DMARD for second-line combination therapy in RA.

Autoimmune response to proteasome activator 28alpha in patients with connective tissue diseases.

OBJECTIVE: To determine the autoimmune response against proteasome activator 28alpha (PA28alpha) in patients with various connective tissue diseases, and to compare the immunoreactivity between anti-PA28alpha and anti-Ki antibodies. METHODS: Serum samples were obtained from 219 patients with various connective tissue diseases. cDNA encoding full-length human PA28alpha and Ki were produced by polymerase chain reaction. Antigens were expressed as glutathione S-transferase (GST) fusion proteins. The immunoreactivity of serum for PA28alpha and Ki was studied by Western blotting. An inhibition test was performed by ELISA using purified Ki antigen. RESULTS: Anti-PA28alpha> antibody was detected in serum from 23% of patients with systemic lupus erythematosus (SLE) and 24% with Sjögren's syndrome (SS). These rates were significantly higher than those for the other rheumatic diseases. Since both PA28alpha and Ki are elements of the PA28 complex and their amino acid sequences share 40.2% homology, immunoreactivity to PA28alpha was studied further. Among 27 anti-Ki positive serum samples, 13 samples (48%) also reacted with PA28alpha, suggesting a relationship between anti-PA28alpha and anti-Ki antibodies. To investigate whether this finding was due to the presence of cross-reacting epitopes for PA28alpha and Ki antigens, an inhibition test was performed by ELISA. The reactivity to purified Ki antigen was not inhibited by preincubation with recombinant PA28alpha. CONCLUSION: Detection of anti-PA28alpha antibody was significantly higher in serum from patients with SLE and SS. The relationship between anti-PA28alpha and Ki antibodies suggests the importance of an antigen-driven system in the induction of an autoimmune response to PA28 complex.

Autoimmune responses to proliferating cell nuclear antigen multiprotein complexes involved in cell proliferation are strongly associated with their structure and biologic function in patients with systemic lupus erythematosus.

OBJECTIVE: To analyze the reaction of lupus sera with proliferating cell nuclear antigen (PCNA) multiprotein complexes (PCNA complexes), which are part of the protein machinery involved in cell proliferation. METHODS: PCNA complexes were purified from rabbit thymus extract by affinity chromatography using anti-PCNA monoclonal antibodies (TOB7, TO17, and TO30); monomeric and trimeric PCNA forms (AK-PCNA) were purified using anti-PCNA serum AK. The reactions to these antigens of 10 anti-PCNA-positive and 40 anti-PCNA-negative sera selected from 560 lupus patients were tested by immunoblotting, immunoprecipitation, and enzyme-linked immunosorbent assays (ELISAs). RESULTS: With one exception (serum OK), anti-PCNA-positive sera reacted exclusively with only the 34-kd polypeptide. In contrast, 14 of 40 anti-PCNA-negative sera reacted with multiple proteins within PCNA complexes. Most anti-PCNA-positive sera probably recognize as epitopes the binding sites for other proteins on PCNA, which are likely hidden when PCNA is complexed with other proteins. As a consequence, only serum OK reacted with the PCNA complex in a series of ELISAs. Using AK-PCNA as a competitive inhibitor, it was determined that serum OK reacts with both the 58-kd polypeptide and the 34-kd PCNA within complexes. Together with the results of a longitudinal analysis, these results suggest that the immune system of patient OK likely recognized the complexed PCNA protein, after which the autoimmune response spread to other elements of the complexes. CONCLUSION: Intermolecular-intrastructural help, leading to the spread of autoimmune response from PCNA to other proteins associated with its biologic function, plays a crucial role in the induction of the autoimmune response seen in lupus patients.

Interaction between fluvoxamine and cotinine or caffeine.

We examined the relationships between plasma fluvoxamine concentrations and plasma levels of cotinine and caffeine, respectively, under steady-state conditions in 30 patients who met DSM-IV criteria for a major depressive disorder and who were being treated with fluvoxamine. The daily dosages of fluvoxamine ranged from 50 to 200 mg (mean +/- SD 108 +/- 42 mg). Eleven patients were smokers and the remaining 19 were nonsmokers. The plasma fluvoxamine concentrations were significantly higher in nonsmokers (0.92 +/- 0.40 ng/ml/mg) than in smokers (0.56 +/- 0.28 ng/ml/mg); in addition, a trend towards negative correlations was observed between the plasma fluvoxamine concentrations and the plasma cotinine levels, although it was not significant. Significant positive correlations were found between the plasma fluvoxamine concentrations and the plasma caffeine levels. These findings are compatible with those in earlier reports that cytochrome P450 1A2 plays a major role in fluvoxamine metabolism.