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Sjögren's syndrome (SS) is an autoimmune disease characterized by periductal lymphocytic infiltration of the salivary and lacrimal glands. SS also exhibits extra-glandular manifestations and specific autoantibodies. Salivary gland ultrasonography (SGUS) is a common procedure used to assess the severity of glandular involvement. However, the association between SGUS and extra-glandular lesions remains poorly understood. This study aimed to identify clinical indices, including disease activity, associated with glandular involvement using SGUS in patients with SS. We included 115 patients with SS and 90 without SS. Patients with SS had significantly higher ultrasonography (US) score than patients without SS. Multivariate analysis revealed focus score, Saxon test positivity, and anti-centromere antibody (ACA) positivity as independent variables associated with the US score in patients with SS. In addition, these results were similar to those obtained in patients with primary SS. Patients with SS and ACA positivity had higher US score and an increased prevalence of hyperechoic bands in the parotid glands and submandibular glands. In conclusion, this study indicated that ACA positivity is associated with the US score in patients with SS. These results suggest that US findings in patients with ACA positivity might show specific changes in the salivary glands, especially fibrosis., (© 2024. The Author(s).)

Systemic sclerosis (SSc) is an autoimmune disease characterized by vascular endothelial dysfunction and skin fibrosis. Recently, the presence and pathogenic role of immune complexes (ICs) of SSc patients were reported. However, the identities of antigens in these ICs are unknown. Therefore, we examined ICs in the serum of SSc patients to elucidate SSc pathogenesis. In this study, IC concentrations in serum samples from SSc and systemic lupus erythematosus (SLE) patients were measured by C1q enzyme-linked immunosorbent assays; immune complex analysis was used for comprehensive identification and comparison of antigens incorporated into ICs (IC-antigens). The expression patterns of SSc-specific IC-antigens in skin sections were investigated by immunohistochemistry. Compared with SLE patients who developed disease because of IC deposition, SSc patients had a greater number of IC-antigens and a smaller difference in IC concentrations, suggesting that SSc pathogenesis is affected by the proteins present in ICs. In contrast, the IC concentration and number of IC-antigens did not significantly differ according to the clinical phenotype of SSc. We identified 478 IC-antigens in SSc patients, including multiple RNAP II-associated proteins that were targeted by antibodies previously associated with SSc pathogenesis. The most frequently detected RNAP II-associated protein, RNA polymerase II transcription subunit 30 (MED30), was strongly expressed at lesion sites and reportedly regulates endothelial differentiation. Therefore, increased expression of MED30 in lesions may have an antigenic effect, and MED30 function may be impaired or inhibited by IC formation. RNAP II-associated proteins may SSc pathogenesis through mechanisms such as the MED30 pathway., Competing Interests: Declarations of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Objectives: Autonomic dysfunction is closely associated with autoimmune diseases (AID) including primary biliary cirrhosis (PBC). The objective of this study was to determine the prevalence of anti-ganglionic (nicotinic) acetylcholine receptor (gAChR) antibodies in patients with AID., Methods: We determined the presence of gAChR antibodies in serum samples from 146 patients (systemic lupus erythematosus [SLE] = 32; rheumatoid arthritis [RA] = 43; systemic sclerosis [SSc] = 38; PBC= 33) without information regarding autonomic symptoms, as well as 34 patients with other neurological diseases [OND], and 73 healthy controls [HC]. We specifically analyzed sera for anti-gAChRα3 and -β4 antibodies using the luciferase immunoprecipitation system (LIPS) assay., Results: LIPS assay detected anti-gAChRα3 and -β4 antibodies in the sera from patients with SLE (12.5%, 4/32), RA (18.6%, 8/43), SSc (13.2%, 5/38), PBC (9.1%, 3/33), OND (2.9%, 1/34), and HC (0.0%, 1/73). There were no significant correlations between the levels of anti-gAChRα3 and -β4 antibodies, and the total titers of autoantibodies in AID., Conclusions: The results demonstrated a significant prevalence of anti-gAChR antibodies in patients with AID, which is independent of the production of other autoantibodies in patients with autoimmune diseases. These anti-gAChR antibodies could mediate the autonomic dysfunction involved in the autoimmune mechanisms of AID.

A 63-year-old man with enlargement of the bilateral submandibular glands visited with elevated serum IgG4. A biopsy specimen showed plasma cell infiltration with more than 50% IgG4/IgG staining, suggesting the existence of IgG4-related disease (IgG4-RD). Positive anti-SS-A/Ro antibody and the labial salivary gland's biopsy suggested existence of primary Sjögren's syndrome (pSS). Administration of glucocorticoid improved the serum IgG4 level while reducing the submandibular gland lesions. Positive TUNEL staining suggested the coexistence of IgG4-RD and pSS.

IgG4-related disease is an emerging disease entity characterized by elevated serum IgG4 concentration and tumefaction or tissue infiltration by IgG4-positive plasma cells. In IgG4-related disease, tumor-like lesions develop in multiple organs, such as the lacrimal gland, salivary gland, lung, pancreas, kidney, and lymph nodes. We report here three cases of IgG4-related orbital inflammation that presented as unilateral pseudotumors. The patients all were men, with an age range of 65-75 years. The patients had been pointed out unilateral intra-orbital masses, and histopathological examinations revealed marked accumulation of IgG4-positive plasma cells (IgG4/IgG ratio: 51.1-71.6%) with fibrosis. But storiform fibrosis was seen in only one case, and no obliterative phlebitis was seen. The serum levels of IgG4 were increased to 178-670 mg/dL. The masses had well-defined homogeneous signal intensities, and they were hypo-intense on T1-weighted MR images and iso-intense on T2-weighted MR images. Gadolinium enhanced mass lesions in two cases. All orbital mass lesions responded well to corticosteroid treatment.

A 68-year-old woman was admitted with bleary eyes and lacrimal gland swelling. A biopsy specimen from a right paravertebral mass lesion detected by computed tomography showed remarkable IgG4-positive plasma cells. Because serum IgG4 was elevated to 3300 mg/dl, IgG4-related disease was diagnosed, with the assistance of fluorodeoxyglucose positron emission tomography (FDG-PET)/computed tomography (CT). Administration of 30 mg of oral prednisolone effectively reduced the lacrimal gland swelling and paravertebral mass volume. Nine months after the initiation of prednisolone, serum IgG4 was reduced to 31.4 mg/dl, and there was norecurrence.

Nakajo-Nishimura syndrome (NNS) is a disorder that segregates in an autosomal recessive fashion. Symptoms include periodic fever, skin rash, partial lipomuscular atrophy, and joint contracture. Here, we report a mutation in the human proteasome subunit beta type 8 gene (PSMB8) that encodes the immunoproteasome subunit β5i in patients with NNS. This G201V mutation disrupts the β-sheet structure, protrudes from the loop that interfaces with the β4 subunit, and is in close proximity to the catalytic threonine residue. The β5i mutant is not efficiently incorporated during immunoproteasome biogenesis, resulting in reduced proteasome activity and accumulation of ubiquitinated and oxidized proteins within cells expressing immunoproteasomes. As a result, the level of interleukin (IL)-6 and IFN-γ inducible protein (IP)-10 in patient sera is markedly increased. Nuclear phosphorylated p38 and the secretion of IL-6 are increased in patient cells both in vitro and in vivo, which may account for the inflammatory response and periodic fever observed in these patients. These results show that a mutation within a proteasome subunit is the direct cause of a human disease and suggest that decreased proteasome activity can cause inflammation.

Activation of the complement cascade via the classical pathway is required for the development of tissue injury in many autoantibody-mediated diseases. It therefore makes sense to block the pathological action of autoantibodies by preventing complement activation through inhibition of autoantibody binding to the corresponding pathogenic autoantigen using targeted Fab antibody fragments. To achieve this, we use bullous pemphigoid (BP) as an example of a typical autoimmune disease. Recombinant Fabs against the non-collagenous 16th-A domain of type XVII collagen, the main pathogenic epitope for autoantibodies in BP, were generated from antibody repertoires of BP patients by phage display. Two Fabs, Fab-B4 and Fab-19, showed marked ability to inhibit the binding of BP autoantibodies and subsequent complement activation in vitro. In the in vivo experiments using type XVII collagen humanized BP model mice, these Fabs protected mice against BP autoantibody-induced blistering disease. Thus, the blocking of pathogenic epitopes using engineered Fabs appears to demonstrate efficacy and may lead to disease-specific treatments for antibody-mediated autoimmune diseases.

It is generally accepted that certain viral infections can trigger the development of autoimmune diseases. However, the exact mechanisms by which these viruses induce autoimmunity are still not understood. In this review, we first describe hypothetical mechanisms by which viruses induce some representative autoimmune diseases. Then, we focus on Epstein–Barr virus (EBV) and discuss its role in the pathogenesis of rheumatoid arthritis (RA). The discussion is mainly based on our own previous findings that (A) EBV DNA and its products EBV-encoded small RNA (EBER) and latent membrane protein 1 (LMP1) are present in the synovial lesions of RA, (B) mRNA expression of the signaling lymphocytic activation molecule-associated protein (SAP)/SH2D1A gene that plays a critical role in cellular immune responses to EBV is reduced in the peripheral T cells of patients with RA, and (C) EBV infection of mice reconstituted with human immune system components (humanized mice) induced erosive arthritis that is pathologically similar to RA. Additionally, environmental factors may contribute to EBV reactivation as follows: Porphyromonas gingivalis peptidylarginine deiminase (PAD), an enzyme required for citrullination, engenders antigens leading to the production of citrullinated peptides both in the gingiva and synovium. Anti-citrullinated peptides autoantibody is an important marker for diagnosis and disease activity of RA. These findings, as well as various results obtained by other researchers, strongly suggest that EBV is directly involved in the pathogenesis of RA, a typical autoimmune disease. [ABSTRACT FROM AUTHOR]

Objective: We evaluated the efficacy and safety of tofacitinib in patients with rheumatoid arthritis (RA) in a real-world setting. Methods: Seventy consecutive patients, for whom tofacitinib was initiated between November 2013 and May 2016, were enrolled. All patients fulfilled the 2010 ACR/EULAR classification criteria for RA. All patients received 5 mg of tofacitinib twice daily and were followed for 24 weeks. Clinical disease activity indicated by disease activity score (DAS)28-ESR, the simplified disease activity index, and the clinical disease activity index as well as adverse events (AEs) were evaluated. Statistical analysis was performed to determine which baseline variables influenced the efficacy of tofacitinib at 24 weeks. Results: Fifty-eight patients (82.9%) continued tofacitinib at 24 weeks. Clinical disease activity rapidly and significantly decreased, and this efficacy continued throughout the 24 weeks: i.e., DAS28-ESR decreased from 5.04 ± 1.33 at baseline to 3.83 ± 1.11 at 4 weeks and 3.53 ± 1.17 at 24 weeks (P<0.0001, vs. baseline). 15 AEs including 5 herpes zoster infection occurred during tofacitinib treatment. The efficacy of tofacitinib was not changed in patients without concomitant use of methotrexate (MTX) or patients whose treatment with tocilizumab (TCZ) failed. Multivariable logistic analysis showed that the number of biologic DMARDs (bDMARDs) previously used was independently associated with achievement of DAS-low disease activity. Conclusions: Our present study suggests that tofacitinib is effective in real-world settings even without concomitant MTX use or after switching from TCZ. Our results also suggest that its efficacy diminishes if started after use of multiple bDMARDs. [ABSTRACT FROM AUTHOR]

Objectives The risk factors of adverse events during a number of currently used treatments for rheumatoid arthritis ( RA) in elderly patients were examined. Methods A retrospective observational study was conducted for 300 elderly RA patients registered in December 2009 at Sasebo Chuo Hospital, Japan, and the adverse events during the treatments for RA were assessed. Results The average age of the patients was 74.3 ± 5.8 years. The Steinbrocker stage was IV in almost one-half of the patients. Methotrexate ( MTX) was used in 54.0% of patients and biologics in 23.0% of patients. Adverse events occurred in 103 patients (34.3%). The most common adverse events were infections (46.6%), including pneumonia (21.4%). Multiple logistic analyses revealed that the factors significantly related to infection were advanced Steinbrocker stage and the existence of respiratory diseases, and that of pneumonia was the existence of diabetes mellitus ( DM). Conclusions The elderly RA patients with advanced stage, respiratory diseases or DM should be monitored for infections, including pneumonia, carefully during treatment. [ABSTRACT FROM AUTHOR]

Objective: To validate the revised Japanese Ministry of Health criteria for the diagnosis of Sjögren's syndrome (SS) (JPN) (1999), The American-European Consensus Group classification criteria for SS (AECG) (2002), and American College of Rheumatology classification criteria for SS (ACR) (2012). Methods: The study subjects were 694 patients with SS or suspected SS who were followed-up in June 2012 at ten hospitals that form part of the Research Team for Autoimmune Diseases, The Research Program for Intractable Disease by the Ministry of Health, Labor and Welfare (MHLW). All patients had been checked for all four criteria of the JPN (pathology, oral, ocular, anti-SS-A/SS-B antibodies). We studied the clinical diagnosis made by the physician in charge and the satisfaction of the above criteria. Results: Of the 694 patients, 499 patients did not have other connective tissue diseases (CTDs). SS was diagnosed in 476 patients (primary SS in 302, secondary SS in 174), whereas non-SS was diagnosed in 218 patients (without other CTDs in 197, with other CTDs in 21) by the physician in charge. The sensitivities of JPN, AECG, and ACR in the diagnosis of all forms of SS (both primary and secondary SS) were 79.6, 78.6, and 77.5 %, respectively, with respective specificities of 90.4, 90.4, and 83.5 %. The sensitivities of the same systems in the diagnosis of primary SS were 82.1, 83.1, and 79.1 %, respectively, with specificities of 90.9, 90.9, and 84.8 %, respectively. The sensitivities of the same systems in the diagnosis of secondary SS were 75.3, 70.7, and 74.7 %, respectively, with specificities of 85.7, 85.7, and 71.4 %, respectively. Conclusion: The sensitivity of JPN to all forms of SS and secondary SS, the sensitivity of AECG to primary SS, and the specificities of JPN and AECG for all forms of SS, primary SS, and secondary SS were highest in the diagnosis of SS in Japanese patients. These results indicate that the JPN criteria for the diagnosis of SS in Japanese patients are superior to ACR and AECG. [ABSTRACT FROM AUTHOR]

We investigated the effects of anti-IL-6 receptor antibody, tocilizumab (TCZ), on lipid metabolism. Nineteen patients with rheumatoid arthritis (RA), entered in clinical case-control study of SAMURAI trial at Sasebo Chuo Hospital, were examined. Nine patients received TCZ monotherapy at 8 mg/kg intravenously every 4 weeks (TCZ group) and 10 patients received conventional DMARDs (control group). Serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), apolipoprotein (Apo) A-1, Apo A-2 and Apo B as well as disease activity score (DAS), C-reactive protein and serum amyloid A protein were examined at baseline and after 3 months of the treatment. IL-6 inversely was correlated with LDL, Apo A-1 and Apo A-2, and also tended to correlate with Apo B. In TCZ group, serum levels of TC, HDL, LDL, Apo A-1 and Apo A-2 were significantly increased after 3 months treatment with TCZ. There was no significant change in Apo B, the atherogenic index, and TC/HDL by the TCZ treatment. Changes in the DAS28-ESR negatively correlated with those in TC. In one patient, whose serum level of TCZ was not detected after 3 months of the treatment, the absence of the increment in serum levels of Apo A-1 and A-2 in the patient was remarkable. All of the markers did not change during 3 months in control group. These data may raise an important issue to evaluate the impact of these alternations in lipid metabolism for longer periods in RA patients treated with TCZ. [ABSTRACT FROM AUTHOR]

We attempted to determine what baseline variables are responsible for the efficacy of tacrolimus at 6 months in Japanese patients with rheumatoid arthritis (RA). One hundred and six RA patients treated with tacrolimus for 6 months were entered in this study. The outcome was set as the achievement of Disease Activity Score 28 C-reactive protein (DAS28-CRP) remission at 6 months. We examined the association of gender, DAS28-CRP at baseline, concomitant use of methotrexate (MTX), and concomitant use of prednisolone with the achievement of DAS28-CRP remission at 6 months by logistic regression analysis. Twenty-three of 106 patients (21.7%) achieved DAS28-CRP remission at 6 months. There was concomitant use of MTX by 20 patients (18.9%), prednisolone by 93 (87.7%), and prednisolone >5 mg/day by 43 (40.6%) at baseline. Logistic regression analysis showed that male gender (first) and moderate disease activity at baseline (second) are independent predictors toward achieving DAS28-CRP remission at 6 months. Maximum tacrolimus dosage administrated for patients over a 6-month period appeared not to be predictive for the DAS28-CRP remission at 6 months. In conclusion, we revealed for the first time that good outcome in RA patients treated with tacrolimus can be predictive by some baseline variables. That is clinically valuable for daily practice in the choice of disease-modifying antirheumatic drugs (DMARDs), especially tacrolimus. [ABSTRACT FROM AUTHOR]

Transmissibility of characteristic lesions to experimental animals may help us understand the pathomechanism of human autoimmune disease. Here we show that human autoimmune disease can be reproduced using genetically engineered model mice. Bullous pemphigoid (BP) is the most common serious autoimmune blistering skin disease, with a considerable body of indirect evidence indicating that the underlying autoantigen is collagen XVII (COL17). Passive transfer of human BP autoantibodies into mice does not induce skin lesions, probably because of differences between humans and mice in the amino acid sequence of the COL17 pathogenic epitope. We injected human BP autoantibody into Col17-knockout mice rescued by the human ortholog. This resulted in BP-like skin lesions and a human disease phenotype. Humanization of autoantigens is a new approach to the study of human autoimmune diseases. [ABSTRACT FROM AUTHOR]

Several clinical trials have demonstrated that leukocytapheresis (LCAP) is a safe and effective therapy for patients with refractory rheumatoid arthritis (RA). However, most of those reports were limited to short-term clinical observation. We have treated 11 RA patients with LCAP and observed them for 24 weeks after the final administration. The 11 cases included 3 diabetes patients, 2 patients with interstitial pneumonia, 1 patient with diffuse panbronchiolitis, and 1 patient with old pulmonary tuberculosis. Alternative therapies for all of these patients were considered difficult. Once-a-week LCAP administration was added for 5 weeks to the previous therapeutic regime in all patients, and the treatment efficacy was prospectively qualified. At 4 weeks after the final LCAP therapy, 8 of the 11 patients (73%) had achieved an American College of Rheumatology (ACR) 20% response, and 3 of the 11 (27%) had achieved both ACR 50% and ACR 70% responses. Although the efficacy decreased after the observation periods, an ACR 20% response was maintained in 5 patients (45%) at 24 weeks. Although only a limited number of patients were examined in this study, the results suggested that LCAP therapy will be beneficial to RA patients, including patients who cannot be treated with tumor necrosis factor inhibitors or conventional disease-modifying antirheumatic drugs. [ABSTRACT FROM AUTHOR]

Abstract: Tumor necrosis factor-alpha (TNF-α) is a potent cytokine that is central to normal immune responses as well as autoimmune inflammatory diseases. The production of TNF-α protein is thus tightly regulated at multiple levels. Translational control is one of the means by which TNF-α production is repressed in unstimulated cells. To examine the mechanism by which the translation of TNF-α mRNA transcripts is repressed, we have used an in vitro translation system. The AU-rich element (ARE) in the 3′ UTR of TNF-α transcripts was sufficient to confer translational repression. This effect was observed using transcripts containing a 5′ m7G cap but not uncapped transcripts, and was independent of a poly(A) tail. Sucrose gradient analysis revealed that ARE-containing transcripts were present at relatively lower amounts in 80S-associated fractions and higher amounts in non-ribosome-bound RNA fractions, with no accumulation of 48S-associated transcripts. ARE-mediated translational repression was competitively inhibited by ARE-containing transcripts. These data indicate that a TNF-α ARE-binding trans-acting factor(s) inhibits the association of the 43S complex with RNA transcripts. [Copyright &y& Elsevier]

A 60-year-old man who had been diagnosed as rheumatoid arthritis admitted to our hospital by dysesthesia on his legs with edema. Nerve conduction velocity test led to diagnosis of mononeuritis multiplex. Magnetic resonance imaging (MRI) of lower legs showed high intensity in slow tau inversion recovery. Typical vasculitis with neutrophil-dominant cell infiltration was observed by muscle biopsy without inflammatory myopathy or fascitis. Diagnosis was made by rheumatoid vasculitis found in crural muscles. Intravenous cyclophosphamide with oral tacrolimus effectively improved dysesthesia with reduction of inflammatory response. [ABSTRACT FROM AUTHOR]

Autonomic neuropathy has been reported in autoimmune rheumatic diseases (ARD) including Sjögren's syndrome, systemic sclerosis, rheumatoid arthritis, and systemic lupus erythematosus. However, the pathophysiological mechanism underlying autonomic dysfunction remains unknown to researchers. On the other hand, autoimmune autonomic ganglionopathy (AAG) is an acquired immune-mediated disorder, which causes dysautonomia that is mediated by autoantibodies against ganglionic acetylcholine receptors (gAChRs). The purpose of this review was to describe the characteristics of autonomic disturbance through previous case reports and the functional tests used in these studies and address the importance of anti-gAChR antibodies. We have established luciferase immunoprecipitation systems to detect antibodies against gAChR in the past and determined the prevalence of gAChR antibodies in various autoimmune diseases including AAG and rheumatic diseases. Autonomic dysfunction, which affects lower parasympathetic and higher sympathetic activity, is usually observed in ARD. The anti-gAChR antibodies may play a crucial role in autonomic dysfunction observed in ARD. Further studies are necessary to determine whether anti-gAChR antibody levels are correlated with the severity of autonomic dysfunction in ARD. [ABSTRACT FROM AUTHOR]

Neuropsychiatric systemic lupus erythematosus (NPSLE) is often difficult to diagnose and distinguish from other diseases, because no NPSLE-specific antibodies have been identified. We developed a novel proteomic strategy for identifying and profiling antigens in immune complexes in the cerebrospinal fluid (CSF), and applied this strategy to 26 NPSLE patients. As controls, we also included 25 SLE patients without neuropsychiatric manifestations (SLE), 15 with relapsing remitting multiple sclerosis (MS) and 10 with normal pressure hydrocephalus (NPH). We identified immune complexes of suprabasin (SBSN) in the CSF of the NPSLE group. The titer of anti-SBSN antibodies was significantly higher in the CSF of the NPSLE group compared to those of the SLE, MS and NPH groups. Microarray data showed that the senescence and autophagy pathways were significantly changed in astrocytes exposed to anti-SBSN antibodies. Our findings indicate that SBSN could be a novel autoantibody for the evaluation of suspected NPSLE. [ABSTRACT FROM AUTHOR]