[Sjögren syndrome]

Genetic insight into dissecting the immunophenotypes and inflammatory profiles in the pathogenesis of Sjogren syndrome

BACKGROUND

Sjogren syndrome (SS) is a chronic systemic autoimmune disease and its pathogenesis often involves the participation of numerous immune cells and inflammatory factors. Despite increased researches and studies recently focusing on this area, it remains to be fully elucidated. We decide to incorporate genetic insight into investigation of the causal link between various immune cells, inflammatory factors and pathogenesis of Sjogren syndrome (SS).

METHODS

Our study leveraged the genetic variants of multi-omics statistics extracted from genome-wide association study (GWAS), the University of Bristol and the FinnGen study. We performed a bidirectional Mendelian randomization and mediation study based on randomly allocated instrumental variables to infer causality, followed by external validation with UK Biobank data and Bayesian colocalization.

RESULTS

We demonstrated that an elevated level of CD27 on IgD + CD24 + B cell, a subset of B cells expressing both IgD and CD24, was associated with a higher risk of SS (OR = 1.119, 95% CI: 1.061-1.179, P < 0.001), while CD3 on CD45RA + CD4 + Treg was a protective factor (OR = 0.917, 95%CI: 0.877-0.959, P < 0.001). Results of meta-analysis and colocalization further supported the significant results identified in the primary analysis. A total of 4 inflammatory cytokines and 7 circulating proteins exhibited potential causal relationships with SS despite no significant result achieved after FDR correction. Finally, results of mediation analysis indicated that CD40L receptor levels had significant mediating effects (β = 0.0314, 95% CI: 0.0004-0.0624, P = 0.0471) at a mediation proportion of 28% (95% CI: 0.364%-55.6%) in causal relationship between CD27 on IgD + CD24 + B cell and SS.

CONCLUSIONS

By providing a novel genetic insight into unveiling the roles of autoimmunity and inflammation in Sjogren syndrome, our findings may potentially lead to identifying new clinical biomarkers for disease monitoring and therapeutic targets that offer more effective alternatives for treating this condition. Therefore, our study may provide valuable evidence for future clinical intervention and targeted immunotherapy.

Severe Hypokalemia and Respiratory Muscle Paralysis: An Atypical Manifestation of Primary Sjögren's Syndrome

Primary Sjögren's syndrome (SS) is a systemic autoimmune disorder primarily affecting exocrine glands, that may occasionally present with severe extra-glandular manifestations. Although rarely, severe hypokalemia and respiratory muscle paralysis may be initial presentations. We report the case of a 33-year-old woman with a recent history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection who presented with headache and generalized muscle weakness. An evaluation revealed severe hypokalemia, acute kidney injury, and metabolic acidosis. Despite intravenous potassium supplementation, her condition rapidly deteriorated, leading to respiratory failure requiring invasive ventilation. Further investigations showed a urinary pH >5.5, indicating distal renal tubular acidosis (dRTA). Positive antinuclear antibody (ANA) titers, SS-related antigen A antibody (anti-Ro/SSA), and lymphocytic infiltration on parotid gland biopsy confirmed a diagnosis of primary SS. Treatment with bicarbonate, potassium supplementation, and oral corticosteroids was initiated, leading to clinical improvement. This case underscores the importance of considering SS in patients with unexplained dRTA and severe hypokalemia, emphasizing the importance of timely diagnosis and tailored therapy in managing systemic manifestations.

Oral Mucosa Capillaroscopy: A Narrative Review

The oral cavity may suffer from diseases and lesions of different natures that can result in changes to the underlying microvasculature. These changes are typically observed during the examination of biopsy samples, but there is still a need to investigate methods for characterizing them in live tissues. Capillaroscopy, a medical imaging technique using polarized light and magnification, has shown promise in providing enhanced imaging of the oral mucosa microvasculature in preliminary studies. The present work proposed to review the literature on what capillaroscopy is, its applications in the imaging of oral mucosa microvasculature, and its diagnostic and prognostic significance in various diseases and conditions. While there is the limited literature available, further research in oral capillaroscopy, particularly in the field of oral oncology, is needed to determine its potential benefits in diagnosing and predicting outcomes for potentially malignant oral disorders and cancers.

Classification of salivary gland biopsies in Sjögren's syndrome by a convolutional neural network using an auto-machine learning platform

BACKGROUND

The histopathological analysis of minor salivary gland biopsies, particularly through the quantification of the Focus Score (FS), is pivotal in the diagnostic workflow for Sjögren's Syndrome (SS). AI-based image recognition using deep learning models has demonstrated potential in enhancing diagnostic accuracy and efficiency in preclinical research.

OBJECTIVES

The primary aim of this investigation was to utilize an auto-machine learning (autoML) platform for the automated segmentation and quantification of FS on histopathological slides, aiming to augment diagnostic precision and speed in SS.

METHODS

A cohort comprising 86 patients with sicca syndrome (37 diagnosed with SS based on the 2016 ACR/EULAR Classification Criteria and 49 non-SS) was selected for an in-depth histological examination. A repository of 172 slides (two per patient) was assembled, encompassing 74 slides meeting the classificatory thresholds for SS (FS ≥ 1, indicative of lymphocytic infiltration) and 98 slides showcasing normal salivary gland histology. The autoML platform utilized (Giotto, L2F, Lausanne Switzerland) employed a Convolutional Neural Network (CNN) architecture (ResNet-152) for the training and validation phases, using a dataset of 172 slides.

RESULTS

The developed model exhibited a reliability score of 0.88, proficiently distinguishing SS cases, with a sensitivity of 89.47% (95% CI: 66.86% to 98.70%) and a specificity of 88.24% (95% CI: 63.56% to 98.54%). The model found histological slides of suboptimal quality (e.g., those compromised during fixation or staining processes) to be the most challenging for accurate classification.

CONCLUSION

AutoML platforms offer a rapid and flexible approach to developing machine learning models, even with smaller datasets, as demonstrated in this study for SS. These platforms hold significant potential for enhancing diagnostic precision and efficiency in both clinical and research settings. Multicentric studies with larger patient cohorts are essential for thorough evaluation and validation of this innovative diagnostic approach.

Sicca syndrome/Sjögren's disease associated with cancer immunotherapy: a narrative review on clinical presentation, biomarkers, and management

INTRODUCTION

Almost one-quarter of immune checkpoint inhibitor (ICI) recipients experience sicca syndrome, while Sjögren's disease (SjD) is estimated at 0.3-2.5%, possibly underreported.

AREAS COVERED

This narrative review (Medline/Embase until January/31/2024) addresses the pathophysiology, incidence, demographic/clinical features, biomarkers, labial salivary gland biopsy (LSGB), fulfillment of the idiopathic SjD (iSjD) classificatory criteria, differential diagnosis, and management of sicca syndrome/SjD associated with ICIs.

EXPERT OPINION

SjD associated with ICIs is underdiagnosed, since studies that performed the mandatory SjD investigation identified that 40-60% of patients with sicca syndrome associated with ICIs meet the iSjD classificatory criteria. LSGB played a fundamental role in recognizing these cases, as most of them had negative anti-Ro/SS-A antibody. Despite the finding of focal lymphocytic sialoadenitis in LSGB samples mimicking iSjD, immunohistochemical analysis provided novel evidence of a distinct pattern for sicca syndrome/SjD associated with ICIs compared to iSjD. The former has scarcity of B lymphocytes, which are a hallmark of iSjD. Additionally, patients with sicca syndrome/SjD associated with ICIs have demographical/clinical/serological and treatment response dissimilarities compared to iSjD. Dryness symptoms are more acute in the former than in iSjD, with predominance of xerostomia over xerophthalmia, and partial/complete response to glucocorticoids. Dryness symptoms in ICI-treated patients warrant prompt SjD investigation.

The effect of intense pulsed light combined with topical 0.05% Cyclosporin A eyedrops in the treatment of Sjögren's syndrome related dry eye

OBJECTIVES

This study aimed to assess the effectiveness and safety of intense pulsed light (IPL) therapy plus topical 0.05% cyclosporine A (CsA) eye drops to treat Sjögren's Syndrome-related dry eyes (SS-DE).

RESEARCH DESIGN AND METHODS

In this prospective, randomized trial included, 60 individuals with SS-DE symptoms were randomized to receive topical eye drops containing either 0.1% sodium hyaluronate (Group S) or 0.05% CsA (Group C) plus IPL therapy. Before the first treatment (baseline), and at 12, 16, and 20 weeks after treatment commencement, we assessed the best corrected visual acuity (BCVA), the Ocular Surface Disease Index (OSDI) score, the Schirmer I test (SIT), noninvasive tear breakup time (NBUT), corneal fluorescein staining (CFS), meibomian gland (MG) dropout, lid margin abnormality, MG expressibility, and meibum quality.

RESULTS

Both groups showed significant improvements in the OSDI, NBUT, CFS, MG expressibility, and meibum quality (all p < 0.05). Group C showed a greater increase in OSDI, NBUT, MG expressibility, and meibum quality (all p < 0.05). Moreover, SIT and lid margin abnormalities significantly improved in Group C (both p < 0.05), but not in Group S.

CONCLUSION

Treatment with 0.05% CsA eyedrops plus IPL therapy could significantly reduce the issues and physical discomfort of patients with SS-DE.

CLINICAL TRIAL

Registered on 20 July 2021, with the registration number ChiCTR2100049059.

A novel enzyme-linked immunosorbent assay tool to evaluate plasma soluble CD226 in primary Sjögren's syndrome

CD226 is an important receptor constitutively expressed on most immune cells, performing vital functions in immune responses. However, the levels of soluble CD226 (sCD226) and its roles in primary Sjögren syndrome (pSS) remain unclear. In this study, we developed two novel mouse anti-human CD226 monoclonal antibodies (mAbs) and established a novel sandwich enzyme-linked immunosorbent assay (ELISA) system, which proved to be highly effective in detecting human sCD226. We then analyzed the expression of sCD226 in the plasma of pSS patients. Our results showed that the levels of sCD226 were significantly lower in patients with pSS compared to healthy controls. The significant decline was also observed in active group and the patients with high levels of IgG or positive anti-SSB. Additionally, reduced sCD226 was found to be negatively correlated with the disease activity of pSS and several clinical manifestations, including arthralgia, fatigue, decayed tooth and interstitial lung disease (ILD). Furthermore, receiver operator characteristics (ROC) curve analysis showed that sCD226 displayed outstanding capacity in discriminating pSS and predicting the disease activity. Altogether, plasma sCD226 emerges as a promising candidate for diagnostic markers in the context of pSS.

Salivary Gland Scintigraphy in Sjögren's Syndrome: A Retrospective Study of Diagnostic Accuracy and Correlation With Histological and Immunological Biomarkers

Introduction Sicca syndrome, characterized by xerophthalmia and xerostomia, is associated with various autoimmune and non-autoimmune conditions, posing diagnostic challenges. Sjögren's syndrome (SS) is the most prevalent systemic autoimmune disease linked to sicca symptoms. This study evaluates the diagnostic accuracy of salivary gland scintigraphy (SGS) in distinguishing SS from non-Sjögren's sicca conditions, alongside other diagnostic tests. Methods A retrospective analysis was conducted at Hospital Universitario La Paz from December 2019 to March 2023, including 142 patients diagnosed with sicca syndrome. Correlations between qualitative and quantitative SGS data (GE Healthcare, Chicago, Illinois) and multiparametric sicca evaluations were assessed. Results Among the 142 patients, 84 (59.15%) were classified as having SS, with 55 (65.48%) seropositive for anti-Ro antibodies. Abnormal SGS results were found in 135 (95.07%) patients. Qualitative SGS categorized seven (4.93%) as mild, 53 (37.32%) as moderate, 50 (35.21%) as severe, and 21 (14.79%) as functionally annulled. Moderate or worse impairment had a sensitivity of 0.88 and a specificity of 0.17. Functional annulment had a sensitivity of 0.17 and a specificity of 0.97. Quantitative SGS using ejection fraction thresholds of ≤30% and ≤20% had sensitivities of 0.35 and 0.18 and specificities of 0.84 and 0.94, respectively. Quantitative SGS metrics correlated with unstimulated whole salivary flow (WUSF; 0.243; p=0.003) and inversely with lymphocytic infiltration (-0.281; p=0.001). The 2016 American College of Rheumatology/European League Against Rheumatism (ACR-EULAR) classification criteria for Sjögren's syndrome demonstrated an area under the curve (AUC) of 0.932, which improved to 0.951 with the inclusion of SGS parameters. Conclusions SGS is a significant diagnostic tool in the multiparametric evaluation of sicca syndrome, showing strong correlations with histological and immunological markers. Its integration into diagnostic criteria enhances the differentiation between SS and non-Sjögren's sicca conditions, suggesting its potential inclusion in future classification frameworks.

Primary Sjogren syndrome - A bibliometric analysis via CiteSpace

This study employs CiteSpace software to analyze the research status, hotspots, and trends of primary Sjogren syndrome (pSS). Relevant publications from 1999 to 2023 were searched in the Web of Science Core Collection (WoSCC) set, followed by generating a network map using CiteSpace software to identify top authors, institutions, countries, keywords, journals, references, and research trends. A total of 3564 valid articles were included in this study. The People Republic of China had the highest number of articles (n = 524), while the University of Bergen emerged as the institution with the highest publication count (n = 94). Mariette X was identified as the author with the most publications (n = 67), whereas Vitali C received recognition as the most cited author (n = 1706). Annals of Rheumatic Diseases stood out as the journal with the highest citation count (n = 2530). Notably, an article published in the Annals of Rheumatic Diseases in 2017 garnered significant attention by being cited a remarkable 304 times. The bibliometric analysis reveals that key areas of research in pSS encompass investigating pathogenesis; advancing and applying targeted biological agents; and establishing treatment and diagnostic standards.

Impact of Airborne Exposure to PM10 Increases Susceptibility to P. aeruginosa Infection

The effects of exposure to airborne particulate matter with a size of 10 μm or less (PM10) on C57BL/6 mouse corneas, their response to Pseudomonas aeruginosa (PA) infection, and the protective effects of SKQ1 were determined. C57BL/6 mouse corneas receiving PBS or SKQ1 were exposed to control (air) or PM10 for 2 weeks, infected, and the disease was documented by clinical score, PMN quantitation, bacterial plate count, RT-PCR and Western blot. PBS-treated, PM10-exposed corneas did not differ at 1 day postinfection (dpi), but exhibited earlier (3 dpi) corneal thinning compared to controls. By 3 dpi, PM10 significantly increased corneal mRNA levels of several pro-inflammatory cytokines, but decreased IL-10, NQO1, GR1, GPX4, and Nrf2 over control. SKQ1 reversed these effects and Western blot selectively confirmed the RT-PCR results. PM10 resulted in higher viable bacterial plate counts at 1 and 3 dpi, but SKQ1 reduced them at 3 dpi. PM10 significantly increased MPO in the cornea at 3 dpi and was reduced by SKQ1. SKQ1, used as an adjunctive treatment to moxifloxacin, was not significantly different from moxifloxacin alone. Exposure to PM10 increased the susceptibility of C57BL/6 to PA infection; SKQ1 significantly reversed these effects, but was not effective as an adjunctive treatment.

Comprehensive analysis of the clinical manifestations and hematological parameters associated with secondary immune thrombocytopenia in patients with primary Sjögren syndrome: An observational study

Primary Sjögren Syndrome (pSS) is a chronic autoimmune disease that primarily affects exocrine glands and can lead to various extraglandular manifestations, including secondary immune thrombocytopenia (ITP). Understanding the clinical and hematological differences in pSS patients with and without secondary ITP is crucial for improved patient management and treatment strategies. This retrospective study, conducted from January 2020 to December 2023, involved a cohort of pSS patients, dividing them into 2 groups: those with secondary ITP and those without. Patients were evaluated using the European League Against Rheumatism Sjögren Syndrome Disease Activity Index (ESSDAI), EULAR Sjögren Syndrome Patient-Reported Index (ESSPRI), Health Assessment Questionnaire, and other hematological parameters. Inclusion criteria were based on the American-European Consensus Group or ACR/EULAR classification criteria for pSS. Exclusion criteria included other autoimmune or hematological disorders, prior splenectomy, recent blood transfusions, and lack of informed consent. Statistical analysis was performed using SPSS software, with various tests applied to analyze the data, including logistic regression to identify risk factors for secondary ITP. Significant differences were noted in fatigue, lymphadenopathy, arthritis, mean age, and ESSDAI scores between the secondary ITP and non-secondary ITP groups. Patients with secondary ITP exhibited higher platelet counts, more prevalent lymphopenia, higher immunoglobulin G (IgG) levels, lower complement 3 levels, and reduced white blood cell and hemoglobin levels. Logistic regression analysis identified lymphadenopathy as a risk factor and arthritis as a protective factor for the development of secondary ITP. The study reveals distinct clinical and hematological characteristics in pSS patients with secondary ITP, suggesting a higher disease activity in this subset. These findings underscore the need for further exploration of these associations to develop more precise treatment approaches for pSS, focusing on preventing secondary ITP and improving patient outcomes.

Uncovering the molecular mechanism of Mume Fructus in treatment of Sjögren's syndrome

BACKGROUND

Modern medicine has no cure for the xerostomia caused by the early onset of Sjögren's syndrome. Mume Fructus is a common Chinese herbal medicine used to relieve xerostomia. However, the molecular mechanisms of the effects of Mume Fructus are unknown. In this study, network pharmacology and molecular docking were used to investigate the mechanisms of action of Mume Fructus on Sjögren's syndrome.

MATERIALS AND METHOD

The Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform database was used to identify the active components and targets of Mume Fructus, and the UniProt database was used to identify the genes encoding these targets. SS-related targets were also identified from the GeneCards and OMIM databases. By finding the intersection of the targets of the compounds and the targets of Sjögren's syndrome, the predicted targets of Mume Fructus in the treatment of Sjögren's syndrome were obtained. Further investigation of the active compounds and their targets was carried out by constructing a network of "medicine-candidate compound-target-disease" using Cytoscape 3.7.2, the Protein-Protein Interaction network using the STRING database and Cytoscape 3.7.2, and key targets were identified by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis on R software. Finally, molecular docking was used to verify the affinity of the candidate compounds to the key targets.

RESULTS

Quercetin, beta-sitosterol, and kaempferol in Mume Fructus interact with AKT1, IL-6, IL-1B, JUN, CASP3, and MAPK8. These results suggest that Mume Fructus exerts its therapeutic effects on the peripheral gland injury of Sjögren's syndrome and its secondary cardiovascular disease and tumorigenesis through anti-inflammatory, anti-oxidant, and anti-tumor pathways.

CONCLUSION

With network pharmacology, this study systematically identified the main active components, targets, and specific mechanisms of the therapeutic effects of Mume Fructus on Sjögren's syndrome, providing both a theoretical basis and research direction for further investigations on Mume Fructus.

Involvement of CCL2 in Salivary Gland Response to Hyperosmolar Stress Related to Sjögren's Syndrome

In primary Sjögren's syndrome (pSS) patients, salivary gland (SG) epithelial cells (SGECs) could be exposed to chronic hyperosmotic stress (HOS), consecutive to their destruction and deregulation, that exacerbates an inflammatory response. The aims of this study were to assess the mechanism accounting for C-C motif chemokine ligand 2 (CCL2) expression in an immortalized human salivary gland epithelial acinar cell line (NS-SV-AC) subjected to HOS, as well as the involvement of CCL2 in pSS. CCL2 mRNA and protein levels were determined via RT-qPCR and ELISA. Reporter plasmids and a promoter pull-down assay were used to identify transcription factors associated with CCL2 mRNA increase. Our data showed that HOS-induced CCL2 mRNA increase was independent of the nuclear factor of activated T-cells 5 (NFAT5) and nuclear factor-kappa B (NFkB) but involved Kruppel-like factor 5 (KLF5). CCL2 protein levels, quantified by enzyme-linked immunosorbent assay (ELISA) in sera samples from pSS patients, correlated with the European Alliance of Associations for Rheumatology's Sjogren's syndrome disease activity index (ESSDAI) score for systemic activity. In addition, CCL2 protein levels were higher in patients with biological activity, cutaneous manifestations, and ESSDAI score superior or equal to five. Our data suggest that chronic HOS could exacerbate pSS disease by contributing to the inflammatory process induced by the expression and secretion of CCL2.

Anti-Idiotypic mRNA Vaccine to Treat Autoimmune Disorders

The 80+ existing autoimmune disorders (ADs) affect billions with little prevention or treatment options, except for temporary symptomatic management, leading to enormous human suffering and a monumental financial burden. The autoantibodies formed in most ADs have been identified, allowing the development of novel anti-idiotypic antibodies to mute the autoantibodies using vaccines. Nucleoside vaccines have been successfully tested as antigen-specific immunotherapies (ASI), with mRNA technology offering multi-epitope targeting to mute multiple autoantibodies. This paper proposes using mRNA technology to produce anti-idiotypic antibodies with broad effectiveness in preventing and treating them. This paper delves into the state-of-the-art mRNA design strategies used to develop novel ASIs by selecting appropriate T cell and B cell epitopes to generate anti-idiotypic antibodies. The low cost and fast development of mRNA vaccines make this technology the most affordable for the global control of ADs.