Current concepts on Sjögren's syndrome - classification criteria and biomarkers

Radiomics Analysis of Apparent Diffusion Coefficient Maps of Parotid Gland to Diagnose Morphologically Normal Sjogren Syndrome

OBJECTIVE

This study investigated novel radiomic features derived from apparent diffusion coefficient (ADC) maps for diagnosing Sjögren syndrome (SS) in patients without visible magnetic resonance morphologic changes.

MATERIALS AND METHODS

This study prospectively analyzed 119 consecutive patients with SS and 95 healthy volunteers using 3.0 T magnetic resonance imaging, including diffusion-weighted imaging with b values of 0 and 1000 s/mm2. Regions of interest (ROIs) were manually delineated along the margins of the largest parotid gland slice on ADC maps, from which 838 quantitative features were automatically extracted. Based on the intraclass correlation coefficient and absolute correlation coefficient, 45 radiomic parameters were selected for analysis. The differentiation between patients with SS and healthy controls was evaluated using univariate analysis and receiver operating characteristic analysis. Multiple radiomic features were integrated using binary logistic regression analysis. Through machine learning algorithms, 4 predictive models were developed, and each was thoroughly evaluated for predictive performance. The Shapley Additive exPlanations (SHAP) approach was employed to elucidate the predictive factors influencing the model.

RESULTS

Twenty-two radiomic parameters demonstrated significant differences between SS and control groups. The AUCs were 0.681 ± 0.100 (0.559~0.878). The optimal diagnostic combination for SS consisted of 6 parameters: 0.975Quantile, 180dr_D(4)_Cluster Prominence, 225dr_D(7)_Entropy, 315dr_D(7)_Entropy, Compactness2, and Max3D Diameter, achieving an AUC of 0.956. The SVM, GBM, and XGBoost models were effectively distinguished SS from healthy controls. Among all the parameters, Max3DDiameter demonstrated the strongest predictive power in the model.

CONCLUSIONS

Radiomic features derived from ADC maps demonstrate significant potential in facilitating the early diagnosis of SS.

Transcriptomic sequencing of multiple salivary glands combined with bioinformatics analysis reveals key genes in primary Sjögren's syndrome

OBJECTIVE

Reveal key genes involved in the pathogenesis of Primary Sjögren's Syndrome (pSS) and identify new potential biomarkers and therapeutic targets.

METHODS

mRNA transcriptome data from pSS patients'and healthy controls'parotid and minor salivary glands were collected from the Gene Expression Omnibus (GEO) database. mRNA sequencing was performed on pSS mouse model submandibular glands. Differentially expressed genes (DEGs) were identified and core genes were screened using protein-protein interaction (PPI)networks. Validation was done through Gene Ontology (GO),Kyoto Encyclopedia of Genes and Genomes (KEGG), immune cell infiltration, heatmap, and Receiver Operating Characteristic (ROC) curve analyses, followed by external validation. Finally, review the clinical studies of drugs targeting these genes.

RESULTS

A total of 113 DEGs were identified, yielding 15core DEGs CD8 A, LCK, SYK, CD2, CD247, CD3D, LCP2, CD3G, CCR7, ITK, CXCR4, B2M, CXCL10, CXCL13, and CXCL9.These core genes were enriched in antigen receptor-mediated and T cell receptor signaling pathways, as well as in the chemokine signaling pathway. Immunocell infiltration analysis revealed that, except for B2M, the expression of other core genes is correlated with the proportion of immune cells. Genes like, CXCL13, CXCL9, CXCR4,CD2,CCR7,and ITK exhibited high diagnostic accuracy for distinguish in pSS patients. Core DEGs such as LCK, SYK, LCP2, and ITK was validated in salivary gland data from pSS patients and mouse models. Drugs targeting LCK, SYK, ITK, and other core genes, with their clinical status, were identified.

CONCLUSION

This study identified key genes in pSS, providing novelinsights into pathogenesis, promising biomarkers, and potential therapeutictargets. Key Points • mRNA transcriptomic sequencing was conducted on submandibular gland specimens from NOD mice simulating pSS and normal mice. • Commonly dysregulated core genes were identified across the minor and parotid salivary glands of pSS patients and healthy controls, as well as in the submandibular glands of NOD and normal mice. • ROC analysis was employed to evaluate their predictive value in the diagnosis of pSS.Genes such as CXCL13, CXCL9, CXCR4, CD2, CCR7, and ITK exhibited high diagnostic accuracy for distinguishing pSS patients. • Genes such as LCK, SYK, and ITK have been validated through external verification and qPCR, and have been identified as targets for clinical drugs.

Rodent models for dry eye syndrome (DES)

Dry eye syndrome (DES) is a range of ophthalmic conditions characterized by compromised tear film homeostasis, resulting from various pathological factors and primarily manifesting as ocular discomfort and impaired ocular surface integrity. With the rise in screen time due to modern lifestyles, the prevalence of DES is increasing annually, posing a significant global public health challenge. Pathophysiologically, DES involves damage to the lacrimal functional unit (LFU), including the lacrimal glands, meibomian glands, and corneoconjunctival epithelium, highlighting its multifactorial etiology. Current treatments mainly focus on artificial tears for moisture replacement and anti-inflammatory therapies, but both are limited. Consequently, animal models are crucial for understanding the complex pathological mechanisms of DES and identifying potential therapeutic agents. Rodent eyes, with their structural and physiological similarities to human eyes and cost-effectiveness, have become widely used in DES research. This manuscript reviews the current understanding of DES pathogenesis and rodent models, discussing their strengths, weaknesses, and relevant genetic models. The aim is to furnish critical insights and provide a scholarly resource to propel future investigative endeavors into the pathogenesis of and therapy for DES.

Gut microbiota on anxiety and depression in primary Sjogren's syndrome: A novel insight

Primary Sjogren's syndrome (pSS) is a prevalent disease in rheumatology and immunology. Anxiety, depression, and other mood disorders are pervasive across diverse sectors of society. Recent theories on the gut-brain axis have elucidated that the gut microbiota considered the second brain of humans, can modulate the central nervous system and behavior by mediating bidirectional response systems, including immunity, vagus nerve, and neuroendocrine pathways. This article reviews recent advancements that explore the mechanism between gut microbiota and emotional disorders in pSS. It aims to provide novel therapies for these emotional disorders in pSS.

Application of lacrimal gland ultrasonography in the evaluation of chronic ocular graft-versus-host-disease

Objective

To investigate the effectiveness of lacrimal gland ultrasonography in the assessment of chronic ocular graft-versus-host-disease (oGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and to establish the correlation between the ocular surface and ultrasonographic results.

Method

The cross-sectional study included 57 participants aged 18 and older, who were at least 100 days after allo-HSCT. The study was conducted at the oGVHD clinic of Peking University People's Hospital between March to June 2023. Patients were categorized into groups according to the International Chronic oGVHD (ICCGVHD) consensus group diagnostic criteria or the 2005 National Institutes of Health (NIH) classification criteria for Chronic GVHD. Demographics and transplantation-related information were collected for all participants, including age, gender, donor-recipient HLA matching, donor-recipient ABO matching, donor-recipient gender combination and duration after allo-HSCT. The disease activity of oGVHD and the severity of ocular surface involvement were assessed using various parameters such as Ocular Surface Disease Index (OSDI), Schirmer test, tear film break-up time (BUT), tear meniscus height, corneal/conjunctival staining and meibomian gland dropout. Lacrimal gland structures were assessed by B-mode and Doppler ultrasonography to measure parameters such as the long diameter, thick diameter, homogeneity and parenchymal vascularization. Statistical analyses were performed to determine differences in ocular surface conditions and lacrimal gland ultrasonographic parameters between groups as well as to determine the correlation between ocular surface condition and lacrimal gland ultrasonographic findings.

Result

(1) Patients with definite and probable oGVHD exhibited a significantly longer duration after allo-HSCT compared to non-oGVHD patients (H=11.264, p<0.01), The median durations were 247(164,894) days and 525(310,928) days, respectively, compared to 204(169,323.25) days for non-oGVHD patients. (2) Compared to non-oGVHD patients, both definite oGVHD patients and probable oGVHD patients showed lower average of Schirmer test (H=31.188, p<0.01), TBUT (H=11.853, p<0.01), tear meniscus height (H=13.630, p<0.01) and higher average of OSDI (F=27.992, p<0.01), corneal staining scores (χ²=23.66, p<0.05) and temporal conjunctival staining scores (χ²=14.84, p<0.05). (3) The B-mode and Doppler ultrasonography parameters in lacrimal glands including long diameter, thick diameter, homogeneity and parenchymal vascularization did not exhibit significant differences between the three groups. (4) The long diameter in lacrimal ultrasonography had significantly positive correlations with tear meniscus height (r=0.297, p<0.05) and significantly negative correlations with temporal conjunctival staining scores (r=-0.313, p<0.05) and staining total scores (r=-0.285, p<0.05). The thick diameter in lacrimal ultrasonography demonstrated significantly positive correlations with tear meniscus height (r=0.404, p<0.01), and significantly negative correlations with OSDI (r=-0.273, p<0.05), corneal staining scores (r=-0.264, p<0.05), nasal conjunctival staining scores (r=-0.271, p<0.05) and staining total scores (r=-0.312, p<0.05). Homogeneity and parenchymal vascularization were not found to be significantly correlated with ocular surface status.

Conclusion

The ocular surface condition in oGVHD patients is worse than that observed in non-GVHD patients. The main manifestations include keratoconjunctival injury and a reduction in tear secretion and tear film stability. These effects appear to be a common result of chemoradiotherapy-induced inflammation and rejection-associated responses. There were no significant differences in the morphology of lacrimal glands as revealed by ultrasonography. This suggests that ocular rejection may not be the primary cause of lacrimal gland changes in oGVHD patients. While ultrasonography can provide insight into tear secretion, its efficacy in diagnosing oGVHD appears limited.

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.

Meta-analysis of mortality-associated factors in primary Sjögren's syndrome patients with interstitial lung disease

The study aims to conduct a meta-analysis on 5-year survival rate and mortality-related factors in the patients with primary Sjögren's syndrome concomitant with interstitial lung disease (pSS-ILD). Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we searched various platforms and databases until November 22, 2023. We used the Newcastle-Ottawa Scale (NOS) for quality assessment and extracted study characteristics and effect sizes. The pooled 5-year survival rate, hazard ratios (HRs), and the corresponding 95% confidence intervals (95% CIs) were then calculated. A p-value of less than 0.05 was considered statistically significant. Patients with pSS-ILD. Mortality in patients with pSS-ILD. Out of 188 articles, seven met the inclusion criteria. The meta-analysis estimated a 5-year survival rate of 82% (73%-91%). Mortality-related factors estimated by the meta-analysis included older age (HRs = 1.06, 95% CI 1.03-1.09, P < 0.0001), history of smoking (HRs = 3.44, 95% CI 2.14-5.53, P < 0.00001), anti-SSA antibody positivity (HRs = 0.41, 95% CI 0.20-0.85, P = 0.02), anti-SSB antibody positivity (HRs = 0.42, 95% CI 0.18-0.98, P = 0.04), reduced forced vital capacity (FVC; HRs = 0.96, 95% CI 0.95-0.98, P < 0.0001), reduced 6-min walk distance (6MWD; HRs = 0.99, 95% CI 0.99-1.00, P = 0.0008), presence of a reticular abnormality (HRs = 3.03, 95% CI 1.54-5.95, P = 0.001), and decreased arterial partial pressure of oxygen (PaO2) levels (HRs = 0.99, 95% CI 0.97-1.00, P = 0.04). The 5-year survival rate for pSS-ILD is 82%. Older age, history of smoking, anti-SSA antibody negativity, anti-SSB antibody negativity, reduced FVC, reduced 6MWD, presence of a reticular abnormality, and decreased PaO2 levels increase the mortality risk in pSS-ILD.

Targeted Therapy for Severe Sjogren's Syndrome: A Focus on Mesenchymal Stem Cells

Primary Sjögren's syndrome (pSS) is an autoimmune disease characterized by the infiltration of lymphocytes on salivary and lacrimal glands, resulting in their dysfunction. Patients suffering from severe pSS have an increased risk of developing multi-organ dysfunction syndrome due to the development of systemic inflammatory response, which results in immune cell-driven injury of the lungs, kidneys, liver, and brain. Therapeutic agents that are used for the treatment of severe pSS encounter various limitations and challenges that can impact their effectiveness. Accordingly, there is a need for targeted, personalized therapy that could address the underlying detrimental immune response while minimizing side effects. Results obtained in a large number of recently published studies have demonstrated the therapeutic efficacy of mesenchymal stem cells (MSCs) in the treatment of severe pSS. MSCs, in a juxtacrine and paracrine manner, suppressed the generation of inflammatory Th1 and Th17 lymphocytes, induced the expansion of immunosuppressive cells, impaired the cross-talk between auto-reactive T and B cells, and prevented the synthesis and secretion of auto-antibodies. Additionally, MSC-derived growth and trophic factors promoted survival and prevented apoptosis of injured cells in inflamed lacrimal and salivary glands, thereby enhancing their repair and regeneration. In this review article, we summarized current knowledge about the molecular mechanisms that are responsible for the beneficial effects of MSCs in the suppression of immune cell-driven injury of exocrine glands and vital organs, paving the way for a better understanding of their therapeutic potential in the targeted therapy of severe pSS.

Fine particulate matter and osteoporosis: evidence, mechanisms, and emerging perspectives

Air pollution, particularly fine particulate matter with an aerodynamic diameter of ≤2.5 μm (PM2.5), has been recognized for its adverse effects on multiple organs beyond the lungs. Among these, the bone began to garner significant attention. This review covers epidemiological, animal, and cell studies on PM2.5 exposure and bone health as well as studies on PM2.5-induced diseases with skeletal complications. Emerging evidence from epidemiological studies indicates a positive association between PM2.5 exposure and the incidence of osteoporosis and fractures, along with a negative association with bone mineral density. Experimental studies have demonstrated that PM2.5 can disrupt the metabolic balance between osteoclasts and osteoblasts through inflammatory responses, oxidative stress, and endocrine disruption, thereby triggering bone loss and osteoporosis. Additionally, this review proposes a secondary mechanism by which PM2.5 may impair bone homeostasis via pathological alterations in other organs, offering new perspectives on the complex interactions between environmental pollutants and bone health. In conclusion, this contemporary review underscores the often-overlooked risk factors of PM2.5 in terms of its adverse effects on bone and elucidates the mechanisms of both primary and secondary toxicity. Further attention should be given to exploring the molecular mechanisms of PM2.5-induced bone impairment and developing effective intervention strategies.

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.

Primary Sjogren's Syndrome Presenting As Pleuritis and Pleural Effusion

Sjogren's syndrome is an autoimmune condition characterized by infiltration of exocrine glands but, in rare cases, can have extraglandular involvement with pleural effusion being an exceedingly rare form. Here we present a case of Sjogren's pleuritis resulting in pleural effusion, a rare initial presentation for Sjogren's syndrome. A woman in her 20s presented to the emergency department after a recent hospitalization for pneumonia, pleural effusion, and pulmonary embolism. She presented to the hospital after discharge with pleuritic chest pain, dyspnea, and a productive cough. She was subsequently found to have a large left pleural effusion that necessitated left video-assisted thoracoscopic surgery with pleural biopsy and decortication of the lung. Infectious etiologies were ruled out during hospitalization. The patient's pleural fluid studies revealed lymphocytic predominance, and biopsy results were consistent with the autoimmune origin, more specifically, Sjogren's serositis. While Sjogren's syndrome is an autoimmune disorder most commonly affecting lacrimal and salivary gland function, it is important to consider extra-glandular involvement in patients with positive serologies and unexplained phenomena. This manuscript aims to provide information regarding diagnostic tools and criteria to arrive at a diagnosis and effectively treat pleural effusion secondary to Sjogren's serositis.

Sjogren's syndrome: Everything you always wanted to know about genetic and epigenetic factors

Primary Sjögren's syndrome (pSS) is a chronic, systemic autoimmune disease characterized by a wide spectrum of glandular and extra-glandular features. Genetic and epigenetic factors play an important role in the disease susceptibility and phenotype. There are a multitude of genes that have been identified as implicated in the pathogenesis of pSS, both in HLA and extra-HLA regions with a strong contribution given by genes in interferon signalling pathways. Among the HLA alleles, the most consistent associations have been found with DR2 and DR3 alleles at the DRB1 locus. Moreover, several gene variants outside the MHC locus are in genes involved in NF-κB signalling, B- and T-cell function and methylation processes possibly responsible for lymphomagenesis. There is still a lack of knowledge on precise genetic patterns and prediction models of diseases, and data on pharmacogenetics is scarce. A comprehensive summary of the common genetic factors and an extensive analysis of novel epigenetic aspects is provided, together with a view on the relationships between novel therapeutic agents for pSS and genetic targets in signalling pathways, aiming at improving tailored treatment strategies in the view of a more personalized medicine.

The Relationship Between Systemic Immune Inflammatory Level and Dry Eye in Patients with Sjögren's Syndrome

Background and objectives: Sjögren Syndrome (SS) is a chronic, systemic, and progressive autoimmune disease in which inflammatory processes play a role. Dry eyes or mouth are present in approximately 95-98% of patients with pSS. This study aimed to evaluate the relationship between SII level and disease activity as well as dry eye involvement in patients with pSS. Materials and methods: A cross-sectional design was employed, and a total of 28 female patients who were aged 18-65 years and were diagnosed with pSS were involved. The Sjögren Syndrome Disease Activity Index (ESSDAI) was calculated in patients. The Schirmer test was applied to all patients. The relationship between SII level and disease activity as well as dry eye involvement in pSS patients was evaluated. Results: In our study, a strong positive correlation was found between the SII value and pSS disease activity, while a negative correlation was found between the Schirmer test, which shows dry eye findings, and eye drying time, and a positive correlation was found with the OSDI. Conclusions: this study reported a correlation between hematological parameters and the development of dry eye in pSS. NLR, PLR, and SII showed statistically significant changes in pSS patients.

Salivary gland biopsy as a prognostic tool in Sjögren's syndrome

INTRODUCTION

Primary Sjögren's syndrome (pSS) is an autoimmune disorder primarily affecting salivary and lacrimal glands, although about 40% of patients experience systemic complications. In this setting, the identification of patient phenotypes characterized by increased risk of extra-glandular involvement still represents an unmet need.

AREAS COVERED

The aim of this paper is to review the scientific evidence on the utility of salivary gland biopsies in pSS, emphasizing their role in defining prognosis. In latest years, research focused on disease-specific clinical, serological, or histological features able to categorize patient prognosis. Among histopathological features, focus score and ectopic germinal centers exhibit associations with glandular and extraglandular manifestations, including higher rates of lymphomagenesis.

EXPERT OPINION

Pathological characterization of salivary glands provides information that go beyond a mere diagnostic or classification utility, providing insights for a stratification of disease severity and for predicting systemic manifestations. Thus, a salivary gland biopsy should be offered to all patients and included in routine practice, even when not strictly required for diagnostic purposes. More advanced analysis techniques of the tissue, including immunohistochemistry and 'omics' should be further explored in longitudinal studies to boost the ability to further stratify and predict disease evolution.

Podoplanin expressing macrophages and their involvement in tertiary lymphoid structures in mouse models of Sjögren's disease

Tertiary lymphoid structures (TLSs) are formed in tissues targeted by chronic inflammation processes, such as infection and autoimmunity. In Sjögren's disease, the organization of immune cells into TLS is an important part of disease progression. Here, we investigated the dynamics of tissue resident macrophages in the induction and expansion of salivary gland TLS. We induced Sjögren's disease by cannulation of the submandibular glands of C57BL/6J mice with LucAdV5. In salivary gland tissues from these mice, we analyzed the different macrophage populations prior to cannulation on day 0 and on day 2, 5, 8, 16 and 23 post-infection using multicolored flow cytometry, mRNA gene analysis, and histological evaluation of tissue specific macrophages. The histological localization of macrophages in the LucAdV5 induced inflamed salivary glands was compared to salivary glands of NZBW/F1 lupus prone mice, a spontaneous mouse model of Sjögren's disease. The evaluation of the dynamics and changes in macrophage phenotype revealed that the podoplanin (PDPN) expressing CX3CR1+ macrophage population was increased in the salivary gland tissue during LucAdV5 induced inflammation. This PDPN+ CX3CR1+ macrophage population was, together with PDPN+CD206+ macrophages, observed to be localized in the parenchyma during the acute inflammation phase as well as surrounding the TLS structure in the later stages of inflammation. This suggests a dual role of tissue resident macrophages, contributing to both proinflammatory and anti-inflammatory processes, as well as their possible interactions with other immune cells within the inflamed tissue. These macrophages may be involved with lymphoid neogenesis, which is associated with disease severity and progression. In conclusion, our study substantiates the involvement of proinflammatory and regulatory macrophages in autoimmune pathology and underlines the possible multifaceted functions of macrophages in lymphoid cell organization.

Dysregulated Ca2+ signaling, fluid secretion, and mitochondrial function in a mouse model of early Sjögren's disease

The molecular mechanisms leading to saliva secretion are largely established, but factors that underlie secretory hypofunction, specifically related to the autoimmune disease Sjögren's syndrome (SS) are not fully understood. A major conundrum is the lack of association between the severity of salivary gland immune cell infiltration and glandular hypofunction. SS-like disease was induced by treatment with DMXAA, a small molecule agonist of murine STING. We have previously shown that the extent of salivary secretion is correlated with the magnitude of intracellular Ca2+ signals (Takano et al., 2021). Contrary to our expectations, despite a significant reduction in fluid secretion, neural stimulation resulted in enhanced Ca2+ signals with altered spatiotemporal characteristics in vivo. Muscarinic stimulation resulted in reduced activation of the Ca2+-activated Cl- channel, TMEM16a, although there were no changes in channel abundance or absolute sensitivity to Ca2+. Super-resolution microscopy revealed a disruption in the colocalization of Inositol 1,4,5-trisphosphate receptor Ca2+ release channels with TMEM16a, and channel activation was reduced when intracellular Ca2+ buffering was increased. These data indicate altered local peripheral coupling between the channels. Appropriate Ca2+ signaling is also pivotal for mitochondrial morphology and bioenergetics. Disrupted mitochondrial morphology and reduced oxygen consumption rate were observed in DMXAA-treated animals. In summary, early in SS disease, dysregulated Ca2+ signals lead to decreased fluid secretion and disrupted mitochondrial function contributing to salivary gland hypofunction.

Meibomian gland dropout of upper eyelids as a novel biomarker for early diagnosis of primary Sjögren's syndrome: a pilot study

Background

Early diagnosis of primary Sjögren's syndrome (pSS) remains difficult due to its insidious onset.

Objectives

To identify whether meibomian gland dropout (MGD) is a sensitive and noninvasive predictor of pSS by studying its association with histopathology in labial salivary gland biopsy in patients with clinically suspected pSS.

Design

Prospective, randomized, multicenter, comparative effectiveness study.

Methods

The study was conducted from July 2022 to July 2023. In all, 56 eligible participants with clinically suspected pSS were recruited from three combined ophthalmology medicine/rheumatology SS clinics. All participants with suspected pSS were evaluated and diagnosed by ophthalmology and rheumatology consultants and underwent infrared imaging of the meibomian glands using Keratograph 5M and histopathological evaluation of labial salivary gland biopsies. The length, width, and tortuosity of the meibomian glands were measured; the dropout rate in the nasal, temporal, and total eyelids was analyzed; and the dropout score was calculated using meibography grading scales.

Results

Among the 56 participants, 34 were identified with pSS, and 22 were diagnosed with non-SS dry eye (NSSDE) and served as the control group. We recorded significant differences in the temporal and total MGD rates of the upper eyelids between the pSS and NSSDE groups (all p < 0.01). Improved prediction accuracy was achieved with the temporal and total MGD rates in the upper eyelids, with area under the curve values of 0.94 and 0.91, and optimal cutoff points of 0.78 and 0.75, respectively.

Conclusion

MGD in the upper eyelids, especially in the temporal portion, is strongly associated with the histopathological outcome of labial salivary gland biopsy in pSS and is proposed as a highly predictive and noninvasive biomarker for the early diagnosis of pSS.

Trial registration

ClinicalTrials.gov identifier: ChiCTR2000038911.

The Current Molecular and Cellular Landscape of Chronic Obstructive Pulmonary Disease (COPD): A Review of Therapies and Efforts towards Personalized Treatment

Chronic obstructive pulmonary disease (COPD) ranks as the third leading cause of global illness and mortality. It is commonly triggered by exposure to respiratory irritants like cigarette smoke or biofuel pollutants. This multifaceted condition manifests through an array of symptoms and lung irregularities, characterized by chronic inflammation and reduced lung function. Present therapies primarily rely on maintenance medications to alleviate symptoms, but fall short in impeding disease advancement. COPD's diverse nature, influenced by various phenotypes, complicates diagnosis, necessitating precise molecular characterization. Omics-driven methodologies, including biomarker identification and therapeutic target exploration, offer a promising avenue for addressing COPD's complexity. This analysis underscores the critical necessity of improving molecular profiling to deepen our comprehension of COPD and identify potential therapeutic targets. Moreover, it advocates for tailoring treatment strategies to individual phenotypes. Through comprehensive exploration-based molecular characterization and the adoption of personalized methodologies, innovative treatments may emerge that are capable of altering the trajectory of COPD, instilling optimism for efficacious disease-modifying interventions.

Fetal and Maternal Outcomes in a Cohort of Patients With Primary Sjogren's Syndrome: An Observational Study

Background Pregnant women with primary Sjogren's syndrome (PSS) have a high incidence of maternal and fetal complications due to immunological variations caused by maternal antibodies (anti-Sjogren's-syndrome-related antigen A (SSA) and anti-anti-Sjogren's-syndrome-related antigen B (SSB) crossing the placenta from the 12th week of gestation, mediating the tissue damage. A multidisciplinary approach is required in the management of such patients. Data regarding the effects of PSS on pregnancy are deficient in the Indian context. Methods This was a retrospective observational study on the maternal and fetal outcomes of PSS on a cohort of pregnant women treated at our tertiary care center between 2011 and 2020. Patients who satisfied the criteria for PSS were included, and patients with other associated autoimmune disorders were excluded. Maternal age, number of miscarriages, prior obstetric history, and maternal and fetal complications were recorded and statistically analyzed. Results There were 16 pregnancies in 10 women with PSS (incidence: 1/1,000 pregnancies/year) in our study. The mean gestational age of the mother at presentation was 31 ± 9.0 weeks. Oligohydramnios in five (11.8), intrauterine fetal demise (IUFD) in two (11.8), and first-trimester medical termination of pregnancy (MTP) in four (23.5) were noted. The weight of neonates was 2.3 ± 0.8 kg, and the mean duration of neonatal intensive care (NICU) stay was seven days. Fetal echo revealed congenital heart block (CHB), with six (50.0%) complete and one (8.3%) incomplete (p = 0.004). One baby needed a permanent pacemaker. Conclusion Maternal and fetal complications are high in our set of mothers with PSS. Early detection, regular follow-up, and a multidisciplinary approach may improve the outcome.

Dysregulated Ca2+ signaling, fluid secretion, and mitochondrial function in a mouse model of early Sjögren's syndrome

Saliva is essential for oral health. The molecular mechanisms leading to physiological fluid secretion are largely established, but factors that underlie secretory hypofunction, specifically related to the autoimmune disease Sjögren's syndrome (SS) are not fully understood. A major conundrum is the lack of association between the severity of inflammatory immune cell infiltration within the salivary glands and glandular hypofunction. In this study, we investigated in a mouse model system, mechanisms of glandular hypofunction caused by the activation of the stimulator of interferon genes (STING) pathway. Glandular hypofunction and SS-like disease were induced by treatment with 5,6-Dimethyl-9-oxo-9H-xanthene-4-acetic acid (DMXAA), a small molecule agonist of murine STING. Contrary to our expectations, despite a significant reduction in fluid secretion in DMXAA-treated mice, in vivo imaging demonstrated that neural stimulation resulted in greatly enhanced spatially averaged cytosolic Ca2+ levels. Notably, however, the spatiotemporal characteristics of the Ca2+ signals were altered to signals that propagated throughout the entire cytoplasm as opposed to largely apically confined Ca2+ rises observed without treatment. Despite the augmented Ca2+ signals, muscarinic stimulation resulted in reduced activation of TMEM16a, although there were no changes in channel abundance or absolute sensitivity to Ca2+. However, super-resolution microscopy revealed a disruption in the intimate colocalization of Inositol 1,4,5-trisphosphate receptor Ca2+ release channels in relation to TMEM16a. TMEM16a channel activation was also reduced when intracellular Ca2+ buffering was increased. These data are consistent with altered local coupling between the channels contributing to the reduced activation of TMEM16a. Appropriate Ca2+ signaling is also pivotal for mitochondrial morphology and bioenergetics and secretion is an energetically expensive process. Disrupted mitochondrial morphology, a depolarized mitochondrial membrane potential, and reduced oxygen consumption rate were observed in DMXAA-treated animals compared to control animals. We report that early in SS disease, dysregulated Ca2+ signals lead to decreased fluid secretion and disrupted mitochondrial function contributing to salivary gland hypofunction and likely the progression of SS disease.

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 the oral repercussions of Sjogren's Syndrome on patient's quality of life: a systematic review and meta-analysis

This study aimed to perform a systematic review to evaluate the impact of the oral repercussions of Sjogren's Syndrome (SS) on the quality of life (QoL) of patients living with this disease. To conduct this work, we followed the PRISMA guidelines. The included studies evaluated oral repercussions of SS and their correlation with QoL. The risk of bias was assessed with the JBI tools for each type of study design. Our findings resulted in 26 articles met the eligibility criteria. Seventeen articles (65.3%) used the OHIP-14 questionnaire to evaluate oral health-related QoL (OHRQoL) and showed that the oral repercussions of SS had a negative impact. Ten studies applied other QoL instruments, in which 5 found a correlation between oral repercussions of SS and poorer OHRQoL, 3 showed no correlation, and 2 were unclear. Due to significant heterogeneity, the meta-analysis was limited to 8 of the 17 studies that used the OHIP-14. The results showed statistically significant poorer OHRQoL in individuals with SS compared to healthy controls. In conclusion, oral repercussions of SS negatively affect QoL. However, future studies should focus on standardized methodology to provide more homogenous and comparable evidence.

The titers of antinuclear antibodies are associated with the degree of inflammation and organ damage in Primary Sjögren's Syndrome

Primary Sjögren's Syndrome (pSS) falls within the category of connective tissue diseases, characterized by the presence of autoantibodies such as antinuclear antibodies (ANA). However, according to the classification criteria for pSS, some patients may exhibit a negative result for autoantibodies. Patients with a negative result for autoantibodies may lack typical features of connective tissue diseases, and the immunological state as well as the extent of organ involvement and damage may differ from those with positive autoantibodies. This study aims to compare the clinical phenotypes of patients with positive and negative autoantibodies, providing insights for disease classification and treatment selection for clinicians. Patients with pSS were grouped based on the presence and titers of their autoantibodies. Subsequently, differences in organ damage and laboratory indicators were compared between these groups, aiming to analyze the value of autoantibody titers in assessing the condition of pSS. (1) Patients with positive ANA exhibited elevated levels of inflammatory indicators, including ESR, IgG levels, lip gland biopsy pathology grade, and overall organ involvement, in comparison with patients with negative ANA (P < 0.05). Furthermore, ANA-positivity correlated with a higher occurrence of multi-organ damage, particularly affecting the skin, mucous membranes, and the hematological system (P < 0.05). (2) As ANA titers increased, patients demonstrated elevated levels of IgG and an escalation in organ involvement (P < 0.05). (3) Patients in the positive autoantibody group (positive for antinuclear antibodies, anti-SSA, or anti-SSB antibodies) had higher IgG levels compared to the negative group (P < 0.05). (4) Patients with positive anti-SSA and anti-SSB antibodies exhibited higher levels of inflammatory indicators and IgG compared to other patients (P < 0.05); however, no significant differences were observed in terms of organ involvement and organ damage. Patients with positive ANA in pSS typically exhibit higher levels of inflammation and an increased likelihood of experiencing multi-organ damage. Furthermore, as the ANA titers increase, both inflammation levels and the risk of multi-organ damage also escalate. Additionally, the presence of anti-SSA and anti-SSB antibodies may contribute to an elevated risk of increased inflammation levels, but does not increase the risk of organ damage.

Oral biosciences: The annual review 2023

BACKGROUND

The Journal of Oral Biosciences is dedicated to advancing and disseminating fundamental knowledge with regard to every aspect of oral biosciences. This review features review articles in the fields of "bone regeneration," "periodontitis," "periodontal diseases," "salivary glands," "sleep bruxism," and "Sjögren's syndrome."

HIGHLIGHT

This review focuses on human demineralized dentin and cementum matrices for bone regeneration, oxidized low-density lipoprotein in periodontal disease and systemic conditions, the relationship between inflammatory mediators in migraine and periodontitis, phosphoinositide signaling molecules in the salivary glands, and the pathophysiologies of sleep bruxism and Sjögren's syndrome.

CONCLUSION

The review articles featured in the Journal of Oral Biosciences have broadened the knowledge of readers regarding various aspects of oral biosciences. The current editorial review discusses the findings and significance of these review articles.

Inflammatory cytokines and their potential role in Sjogren's syndrome risk: insights from a mendelian randomization study

AIM

This study aimed to investigate the causal impact of inflammatory cytokines on Sjogren's Syndrome (SS) and to identify potential biomarkers for SS clinical management using Mendelian Randomization (MR).

MATERIALS AND METHODS

Leveraging GWAS summary data of inflammatory cytokines and SS, we executed the first two-sample MR analysis. Genetic variants from prior GWASs associated with circulating inflammatory cytokines served as instrumental variables (IVs). Data regarding cytokines were analyzed using the Olink Target-96 Inflammation panel, synthesizing data from 14,824 participants. GWAS summary statistics for SS were procured from the UK Biobank, focusing on samples of European ancestry. To discern the causal relationship between inflammatory cytokines and SS, several MR methodologies, including inverse variance weighted (IVW) and MR-Egger regression, were applied.

RESULTS

After rigorous IV quality control, 91 cytokines were incorporated into the MR analysis. The IVW analysis identified 8 cytokines with a positive association to SS: Axin-1 (OR 2.56, 95% CI 1.07-6.10), T-cell surface glycoprotein CD5 (OR 1.81, 95% CI 1.08-3.02), CUDP1 (OR 1.61, 95% CI 1.00-2.58), CXCL10 (OR 1.92, 95% CI 1.25-2.95), IL-4 (OR 2.18, 95% CI 1.22-3.91), IL-7 (OR 2.35, 95% CI 1.27-4.33), MCP-2 (OR 1.27, 95% CI 1.05-1.54), and TNFRSF9 (OR 1.83, 95% CI 1.03-3.24), suggesting their potential in increasing SS risk.

CONCLUSION

Our study conducted through MR, identified various inflammatory cytokines associated with SS risk, validating some previous research results and offering some new potential biomarkers for SS. However, these findings necessitate further research for validation and exploration of their precise role in the onset and progression of SS.

Advances in Sjögren's Syndrome Dry Eye Diagnostics: Biomarkers and Biomolecules beyond Clinical Symptoms

Sjögren's syndrome dry eye (SSDE) is a subset of Sjögren's syndrome marked by dry eye symptoms that is distinct from non-Sjögren's syndrome dry eye (NSSDE). As SSDE can lead to severe complications, its early detection is imperative. However, the differentiation between SSDE and NSSDE remains challenging due to overlapping clinical manifestations. This review endeavors to give a concise overview of the classification, pathophysiology, clinical features and presentation, ocular and systemic complications, clinical diagnosis, and management of SSDE. Despite advancements, limitations in current diagnostic methods underscore the need for novel diagnostic modalities. Thus, the current review examines various diagnostic biomarkers utilized for SSDE identification, encompassing serum, salivary, and tear analyses. Recent advancements in proteomic research and exosomal biomarkers offer promising diagnostic potential. Through a comprehensive literature review spanning from 2016 to 2023, we highlight molecular insights and advanced diagnostic modalities that have the potential to enhance our understanding and diagnosis of SSDE.

Ocular and eyelid involvement in collagen vascular diseases. Part I. Sjögren syndrome and systemic lupus erythematosus

Collagen vascular disease is a heterogeneous group of autoimmune diseases that affect multiple organ systems. Sjögren syndrome, dermatomyositis, scleroderma, systemic lupus erythematosus, and sarcoidosis are collagen vascular diseases that often present with characteristic cutaneous manifestations. Although less known, various ocular manifestations that affect both external and internal structures of the eye can be seen in these conditions. Multidisciplinary management between dermatologists and ophthalmologists is essential in the early diagnosis and management of collagen vascular diseases affecting both the skin and eye. Part I of our series will discuss the ocular manifestations, their diagnosis, and therapeutic options in Sjögren syndrome and systemic lupus erythematosus.

Clinical Biomarkers in Otolaryngology-Head and Neck Surgery: Autoimmune Diseases

OBJECTIVE

The purpose of this article is to review the literature and compile promising and clinically relevant biomarkers in autoimmune disease related to otolaryngology-head and neck surgery.

STUDY DESIGN

Narrative review.

METHODS

Pubmed and Google Scholar were queried using combined key words such as "biomarkers" and "otolaryngology." Additional queries were made with combined key words such as "biomarkers" and a particular subspecialty such as "autoimmune" or "Meniere's" to maximize yield of relevant titles. Subsequently, specific biomarkers identified, such as "anti-TPO-antibodies," were used as key words. Relevant titles were reviewed and selected for abstract review. Applicable abstracts were then selected for review of the full text.

RESULTS

Biomarkers that are currently in clinical use for the management of autoimmune diseases within the field of otolaryngology were included in this review. The compiled biomarkers were then detailed individually regarding their molecular characteristics, function, and clinical significance.

CONCLUSIONS

Based on this literature review, there are several biomarkers currently in clinical use within the field of otolaryngology relating to autoimmune diseases. The majority of these biomarkers are in the form of proteins such as Cogan peptide and c-ANCA. This survey may serve as a comprehensive resource on biomarkers for autoimmune diseases in clinical otolaryngology.

Network pharmacology identifies the inhibitory effect of Yiqiyangyinquyu prescription on salivary gland inflammation in Sjögren's syndrome

This study aimed to explore the mode of action of Yiqiyangyinquyu prescription (YP) against Sjögren's syndrome (SS) by combining network pharmacology with molecular docking techniques. YP's active components and target proteins were identified using the BATMAN-traditional Chinese medicine database. Concurrently, targets associated with SS were extracted from databases, including Genecards, Online Mendelian Inheritance in Man, and Therapeutic Target Database. The standard targets were then imported into the STRING database to construct a protein-protein interaction network. We then conducted gene ontology and Kyoto encyclopedia of genes and genomes enrichment analyses, which were succeeded by molecular docking studies to validate core active components and key targets. Finally, in vitro experiments and molecular dynamics simulation were conducted to substantiate the therapeutic efficacy of YP in treating SS. A total of 206 intersection targets and 46 active compounds were identified. Gene ontology analysis unveiled that YP targets were primarily enriched in cellular responses to chemical stress, inflammation, and cell proliferation. Key enriched signaling pathways encompassed the interleukin 17, hypoxia-inducible factor-1, tumor necrosis factor (TNF-α), and advanced glycation end products-receptor for AGEs (AGE-RAGE) signaling pathways. Molecular docking results demonstrated high-affinity between neotanshinone C, tanshiquinone B, miltionone I, TNF-α, interleukin 1 beta (IL-1β), and interleukin 6 (IL-6). Noteworthy, TNF-α, considered the most important gene in YP against SS, binds to YP most stably, which was further validated by molecular dynamics simulation. In vitro experiments confirmed YP's capacity to reduce TNF-α, IL-1β, and IL-6 expression, effectively alleviating SS-related inflammation. YP demonstrated a significant anti-inflammatory effect by suppressing inflammatory cytokines (TNF-α, IL-6, and IL-1β), providing experimental evidence for its clinical application in treating SS.

A lower prevalence of malignant lymphoma in Sjögren's syndrome patients: A cross-sectional study

OBJECTIVE

This study aims to determine the prevalence and risk factors associated with lymphoma in primary Sjögren's syndrome (pSS).

METHODS

We conducted a cross-sectional study on pSS patients who were registered into the Integrated Data Repository (IDR) at the University of Florida (UF) Health Shands Hospital. The parameters, such as age, sex, race, and smoking status, were included. Lymphoma types in pSS were categorized. The clinical and laboratory features were compared between pSS patients with and those without lymphoma by utilizing the items in the EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI).

RESULTS

Among 1,211,343 patients, we found 6799 patients (0.56%) with lymphomas and 2562 patients (0.21%) with pSS. Out of the 2562 pSS patients, 67 patients (2.6%) were diagnosed with lymphoma. The difference in the clinical and laboratory features listed under the ESSDAI domains between pSS patients with lymphomas and pSS without it was significant (p < 0.05 or 0.01): fever, weight loss, lymphadenopathy, splenomegaly, lacrimal gland diseases, cough, shortness of breath, hematuria, cerebrovascular accident diseases, peripheral nerve involvement due to vasculitis, neutropenia, and thrombocytopenia.

CONCLUSION

We report 2.6% of lymphoma prevalence in pSS, lower than previously reported in the literature.

Hyposalivation but not Sjögren's syndrome associated with microbial dysbiosis in women

Background

Saliva modulates the environment of the oral biofilm through pH buffer, microbial attachment to host surfaces, and nutritional source. The ecology of stress occurs when a physical factor adversely impacts an ecosystem or its biotic components. Therefore, reduced salivary flow can affect oral-host balance. The leading causes of hyposalivation include disease-associated Sjögren's syndrome (SS) and menopausal women as aging-associated. However, little is known about the oral microbiome integrated with sex hormones in hyposalivation. This study aimed to characterize the hyposalivation microbiome caused by aging or disease affecting the salivary glands in women.

Methods

We included 50 women older than 40 years of age in any menopausal phase. We collected stimulated saliva from 25 women diagnosed with SS (SS) and 25 without SS (non-SS). The bacterial profile of the patients was obtained by 16S rRNA sequencing. Bioinformatics analysis used machine learning to analyze the cohort's signs, symptoms, and bacterial profile. Salivary estradiol as a sex hormone variation level was determined.

Results

We obtained that 79% of the SS group, and 52% of the non-SS group had hyposalivation. We found a negatively correlated Prevotella-age and Rothia-estradiol in the SS group. Highlight, we found that the cause of the hyposalivation in the study did not explain differences in microbial diversity comparing non-SS and SS groups. Therefore, microbial communities found in hyposalivation but not related to systemic conditions suggest that changes in the oral environment might underpin host-microbial balance.

Conclusion

The salivary microbiome was similar in women with and without SS. However, hyposalivation showed two distinctive clusters associated with the bacterial population profiles. Our study suggests that local ecological disturbances could drive the change in the microbiome.

The Role of MRI in Differentiating Demyelinating and Inflammatory (not Infectious) Myelopathies

Demyelinating and inflammatory myelopathies represent a group of diseases with characteristic patterns in neuroimaging and several differential diagnoses. The main imaging patterns of demyelinating myelopathies (multiple sclerosis, neuromyelitis optica spectrum disorder, acute disseminated encephalomyelitis, and myelin oligodendrocyte glycoprotein antibody-related disorder) and inflammatory myelopathies (systemic lupus erythematosus-myelitis, sarcoidosis-myelitis, Sjögren-myelitis, and Behçet's-myelitis) will be discussed in this article, highlighting key points to the differential diagnosis.

Review of genes potentially related to hyposecretion in male non-obese diabetic (NOD) mice, a Sjögren's syndrome model

BACKGROUND

Sjögren's syndrome (SS) is known to cause dry eyes and mouth due to inflammation of the lacrimal and salivary glands. However, some reports imply that other factors trigger dry eyes and mouth. We previously investigated various factors using RNA-sequencing analysis of lacrimal glands from male non-obese diabetic (NOD) mice, an SS model. In this review, we described (1) the exocrine features of male and female NOD mice, (2) the up- and down-regulated genes in the lacrimal glands of male NOD mice as revealed by our RNA-sequencing data, and (3) comparisons between these genes and data in the Salivary Gland Gene Expression Atlas.

HIGHLIGHTS

Male NOD mice exhibit a steady worsening of lacrimal hyposecretion and dacryoadenitis, whereas females exhibit a complex pathophysiological condition that includes diabetic disease, salivary hyposecretion, and sialadenitis. Ctss, an up-regulated gene, is a potential inducer of lacrimal hyposecretion and is also expressed in salivary glands. Two other up-regulated genes, Ccl5 and Cxcl13, may worsen the inflammation of SS in both the lacrimal and salivary glands. The genes Esp23, Obp1a, and Spc25 were detected as down-regulated, but judging the relationship between these genes and hyposecretion is difficult as only limited information is available. Another down-regulated gene, Arg1, is involved in lacrimal hyposecretion, and it also has the potential to cause salivary hyposecretion in NOD mice.

CONCLUSION

In NOD mice, males may be better than females at evaluating the pathophysiology of SS. Some regulated genes revealed by our RNA-sequencing data might be potential therapeutic targets for SS.

Non-Coding RNA in Salivary Extracellular Vesicles: A New Frontier in Sjögren's Syndrome Diagnostics?

Sjögren's syndrome is an autoimmune rheumatic disease characterized by inflammation of the salivary and lacrimal glands, often manifesting as dry mouth and dry eyes. To simplify diagnostics of primary Sjögren's syndrome (pSS), a non-invasive marker is needed. The aim of the study was to compare the RNA content of salivary extracellular vesicles (EVs) between patients with pSS and healthy controls using microarray technology. Stimulated whole saliva was collected from 11 pSS patients and 11 age-matched controls. EV-RNA was isolated from the saliva samples using a Qiagen exoRNeasy Midi Kit and analyzed using Affymetrix Clariom D™ microarrays. A one-way ANOVA test was used to compare the mean signal values of each transcript between the two groups. A total of 9307 transcripts, coding and non-coding RNA, were detected in all samples. Of these transcripts, 1475 showed statistically significant differential abundance between the pSS and the control groups, generating two distinct EV-RNA patterns. In particular, tRNAs were downregulated in pSS patients, with the transcript tRNA-Ile-AAT-2-1 showing a 2-fold difference, and a promise as a potential biomarker candidate. This study therein demonstrates the potential for using salivary EV-RNA in pSS diagnostics.

Integrated Analysis Identifies Upregulated SAMD9L as a Potential Biomarker Correlating with the Severity of Primary Sjögren's Syndrome

Background

Primary Sjögren's syndrome (pSS) is an autoimmune disease with lymphocytic infiltration of the salivary and lachrymal glands, whose present disease-specific objective indicators are few and have shortcomings that should be addressed. An integrated analysis of sequencing data from different cohorts has the potential to unveil novel biomarkers in pSS.

Methods

We identified 3 GEO datasets, including gene expression data from minor salivary gland (MSG) biopsy samples of 49 patients with pSS and 31 non-pSS and whole blood cells of 30 pSS patients and 30 healthy controls (HCs). Differentially expressed genes (DEGs) involved in pSS were identified from these datasets. Function Enrichment Analyses of common upregulated DEGs and PPI (protein-protein interaction) networks were performed. Furthermore, we have carried out further analysis of these DEGs to explore their potential clinical significance and diagnostic efficacy as a biomarker for pSS. Sterile Alpha Motif Domain Containing 9 Like (SAMD9L), one of the DEGs, has been identified as a promising candidate biomarker that correlates with the severity of pSS. This has been validated by analyzing local clinical samples from 30 pSS and non-pSS patients' MSG biopsies, as well as serum samples of 18 pSS and HC individuals. Finally, we performed correlation analysis to understand the relationship between SAMD9L and infiltrated immune cells.

Results

We identified 10 common highly expressed DEGs in pSS of different tissues. These genes were mainly involved in virus infection-related pathways and inferno-related pathways. GEO data and our clinical data showed that SAMD9L increases with disease severity. Public and local cohorts showed that SAMD9L has high diagnostic performance (AUC=0.845-0.867) as a biomarker, and its AUC was comparable to the Focus score when combined with RF or SSA.

Conclusion

Up-regulated SAMD9L may serve as a promising novel pSS diagnostic biomarker and have potential value for evaluating the severity of pSS.

Ultra-High-Frequency Ultrasonography of Labial Glands in Pediatric Sjögren's Disease: A Preliminary Study

Sjögren's disease (SD) is a chronic autoimmune disease primarily affecting lacrimal and salivary glands. The diagnosis of pediatric SD mostly relies on clinical suspect, resulting in a significant diagnostic delay. Recently, ultrahigh-frequency ultrasound (UHFUS) of labial glands has been proposed as a diagnostic method in adults with suspected SD. Until now, there have been no studies about UHFUS in pediatric diagnostic work-up. The aim of the study was to evaluate the potential role of UHFUS of minor salivary glands in pediatric SD. Consecutive pediatric patients with a diagnosis of pediatric SD seen at AOU Meyer IRCSS were evaluated. Intraoral UHFUS scan of the lip mucosa was performed with Vevo MD equipment, using a 70 MHz probe with a standardized protocol and the images were independently reviewed by two operators. Lip salivary glands were assessed by using a four-grade semiquantitative scoring system for parenchymal alteration and vascularization. Twelve patients were included. When applying UHFUS to this cohort of patients, all patients showed a UHFUS grade of ≥1 with 8/12 showing a mild glandular alteration (i.e., grade 1), 2/12 a moderate glandular alteration (i.e., grade 2) and finally 2/12 a severe glandular alteration (i.e., grade 3). Moderate intraglandular vascularization was seen in 9/12, with only 3/12 showing mild intraglandular vascularization. Due to limited size of the sample, the relationship between histological findings, autoantibodies status and UHFUS grade could not be performed. This preliminary study seems to report UHFUS as feasibility technique to identify salivary gland alterations in children with a clinical suspect of SD.

Magnetic resonance imaging parameters on lacrimal gland in thyroid eye disease: a systematic review and meta-analysis

BACKGROUND

Thyroid eye disease is an extrathyroidal manifestation of Graves' disease and is associated with dry eye disease. This is the first systematic review and meta-analysis to evaluate the role of magnetic resonance imaging lacrimal gland parameters in thyroid eye disease diagnosis, activity grading, and therapeutic responses prediction.

METHODS

Up to 23 August, 2022, 504 studies from PubMed and Cochrane Library were analyzed. After removing duplicates and imposing selection criteria, nine eligible studies were included. Risk of bias assessment was done. Meta-analyses were performed using random-effect model if heterogeneity was significant. Otherwise, fixed-effect model was used. Main outcome measures include seven structural magnetic resonance imaging parameters (lacrimal gland herniation, maximum axial area, maximum coronal area, maximum axial length, maximum coronal length, maximum axial width, maximum coronal width), and three functional magnetic resonance imaging parameters (diffusion tensor imaging-fractional anisotropy, diffusion tensor imaging-apparent diffusion coefficient or mean diffusivity, diffusion-weighted imaging-apparent diffusion coefficient).

RESULTS

Thyroid eye disease showed larger maximum axial area, maximum coronal area, maximum axial length, maximum axial width, maximum coronal width, diffusion tensor imaging-apparent diffusion coefficient/ mean diffusivity, and lower diffusion tensor imaging-fractional anisotropy than controls. Active thyroid eye disease showed larger lacrimal gland herniation, maximum coronal area, diffusion-weighted imaging-apparent diffusion coefficient than inactive. Lacrimal gland dimensional (maximum axial area, maximum coronal area, maximum axial length, maximum axial width, maximum coronal width) and functional parameters (diffusion tensor imaging-apparent diffusion coefficient, diffusion tensor imaging-apparent diffusion coefficient) could be used for diagnosing thyroid eye disease; lacrimal gland herniation, maximum coronal area, and diffusion-weighted imaging-apparent diffusion coefficient for differentiating active from inactive thyroid eye disease; diffusion tensor imaging parameters (diffusion tensor imaging-fractional anisotropy, diffusion tensor imaging-mean diffusivity) and lacrimal gland herniation for helping grading and therapeutic responses prediction respectively.

CONCLUSIONS

Magnetic resonance imaging lacrimal gland parameters can detect active thyroid eye disease and differentiate thyroid eye disease from controls. Maximum coronal area is the most effective indicator for thyroid eye disease diagnosis and activity grading. There are inconclusive results showing whether structural or functional lacrimal gland parameters have diagnostic superiority. Future studies are warranted to determine the use of magnetic resonance imaging lacrimal gland parameters in thyroid eye disease.

Identification of Salivary Metabolic Signatures Associated with Primary Sjögren's Disease

Sjögren's disease (SjD) is the second most prevalent autoimmune disorder that involves chronic inflammation of exocrine glands. Correct diagnosis of primary SjD (pSjD) can span over many years since disease symptoms manifest only in advanced stages of salivary and lachrymal glandular destruction, and consensus diagnostic methods have critical sensitivity and selectivity limitations. Using nuclear magnetic resonance (NMR) spectroscopy, we determined the composition of metabolites in unstimulated saliva samples from 30 pSjD subjects and 30 participants who do not have Sjögren's disease (non-Sjögren's control group, NS-C). Thirty-four metabolites were quantified in each sample, and analysis was conducted on both non-normalized (concentration) and normalized metabolomics data from all study participants (ages 23-78) and on an age-restricted subset of the data (ages 30-70) while applying false discovery rate correction in determining data significance. The normalized data of saliva samples from all study participants, and of the age-restricted subset, indicated significant increases in the levels of glucose, glycerol, taurine, and lactate, as well as significant decreases in the levels of 5-aminopentanoate, acetate, butyrate and propionate, in subjects with pSjD compared to subjects in the NS-C group. Additionally, a significant increase in choline was found only in the age-restricted subset, and a significant decrease in fucose was found only in the whole study population in normalized data of saliva samples from the pSjD group compared to the NS-C group. Metabolite concentration data of saliva samples from all study participants, but not from the age-restricted subset, indicated significant increases in the levels of glucose, glycerol, taurine, and lactate in subjects with pSjD compared to controls. The study showed that NMR metabolomics can be implemented in defining salivary metabolic signatures that are associated with disease status, and can contribute to differential analysis between subjects with pSjD and those who are not affected with this disease, in the clinic.

A case report of hypokalemic periodic muscular weakness secondary to Sjögren's syndrome with distal renal tubular acidosis

Key Clinical Message

An underlying autoimmune condition should be suspected in patients who presented with periodic muscular weakness secondary to distal RTA that leads to hypokalemia because distal RTA is commonly associated with autoimmune disorders such as Sjögren's syndrome.

Abstract

A 22-year-old female presented with a sudden onset of bilateral weakness in both upper and lower limbs. The patient had a history of muscular weakness secondary to hypokalemia and dryness of the eyes for the last 3 years. Laboratory investigations revealed decreased potassium and metabolic acidosis. Further investigations confirmed distal renal tubular acidosis (RTA) and Sjögren's syndrome. A diagnosis of distal RTA secondary to Sjögren's syndrome was made. Her potassium levels were replaced, and she was discharged with oral potassium supplements, steroids, and artificial tears.

Aquaporin 5 in the eye: Expression, function, and roles in ocular diseases

As a water channel protein, aquaporin 5 (AQP5) is essential for the maintenance of the normal physiological functions of ocular tissues. This review provides an overview of the expression and function of AQP5 in the eye and discusses their role in related eye diseases. Although AQP5 plays a vital role in ocular functions, such as maintaining corneal and lens transparency, regulating water movement, and maintaining homeostasis, some of its functions in ocular tissues are still unclear. Based on the key role of AQP5 in eye function, this review suggests that in the future, eye diseases may be treated by regulating the expression of aquaporin.

Phases and Natural History of Sjögren's Disease: A New Model for an Old Disease?

Sjögren's disease (SjD) is an archetypal and heterogenous autoimmune disorder that is characterized by exocrine glandular dysfunction. A proportion of patients develop severe extraglandular manifestations, such as cryoglobulinemia, and have an increased risk of lymphoma, both of which can adversely affect quality of life and occasionally mortality. As with most autoimmune disorders, the pathogenesis is poorly understood and difficult to predict, and, frustratingly, there is a lack of targeted therapies to cure this disease. We review the disease manifestations of SjD and propose a staged model for understanding the evolution of pathology. In longitudinal studies, most patients remain relatively stable in terms of their laboratory and clinical parameters. However, in the setting of various risk factors, a proportion of patients develop severe symptoms and/or lymphoma. We discuss potential underlying mechanisms for disease progression and the strengths and limitations of using a staged model to correlate the pathogenesis and spectrum of manifestations in SjD. Ultimately, understanding how and why some patients remain relatively stable, whereas others progress and develop florid systemic disease and a fraction develop lymphoma, is key to developing preventative and therapeutic treatments.

Association between Sjögren's Syndrome and Periodontitis: Epidemiological, Fundamental and Clinical Data: A Systematic Review

In recent decades, researchers have investigated the bidirectional links between periodontal disease and systemic diseases, and the results have allowed the development of the concept of periodontal medicine. This concept incorporates and analyzes the mutually influential interactions that can occur between periodontitis and systemic diseases such as diabetes mellitus or cardiovascular diseases. Sjögren's syndrome (SS) is a chronic autoimmune disorder that targets the exocrine glands of the body, such as the lacrimal and salivary glands. The amount of saliva produced may gradually decrease with the progression of the disease, which can have an impact on the structures within the oral cavity. Although the reduction in saliva flow produces negative effects in the oral cavity, a direct association between Sjögren's syndrome and periodontal disease has not yet been demonstrated. Available studies on this topic have not identified significant differences in the periodontal status of patients with Sjögren's syndrome and control groups at the clinical and bacteriological levels. On the other hand, other studies on this topic consider that patients with periodontitis have a higher risk of developing Sjögren's syndrome than the general population. Therefore, the results remain inconclusive, highlighting the need for further complementary studies.

Sialography: a pictorial review

Non-tumour inflammatory and obstructive salivary gland pathologies such as sialadenitis, sialolithiasis, sialadenosis, ductal strictures, etc. require precise radiological evaluation and mapping of salivary gland ductal system for better treatment outcome. Conventional sialography is considered as a useful and reliable technique in evaluation of salivary glands especially intrinsic and acquired abnormalities involving the ductal system and is useful for detection of non-radiopaque sialoliths which are invisible on routine plain radiographs. Primarily sialography is used as a diagnostic tool, additionally it plays an important therapeutic role as salivary gland lavage in cases of recurrent salivary gland infections and in obstructive salivary gland disorders by helping in clearance of mucous plugs or small sialoliths within the ducts. Recently, diagnostic performance of computed tomography (CT) sialography is being explored and has been reported to have high sensitivity in detection of small sialoliths and allows differentiation of sialoliths from other calcifications in glandular ductal system. Multiplanar three dimensional (3D) reconstructed CT images have been reported to play a key role in determination of anatomical location or extent of salivary gland disease without superimposition or distortion of structures. This review aims to discuss the disease specific applications of sialography and CT Sialography in particular for visualization of salivary gland disorders.

Exosomes as biomarkers and therapeutic delivery for autoimmune diseases: Opportunities and challenges

Exosomes are spherical lipid bilayer vesicles composed of lipids, proteins and nucleic acids that deliver signaling molecules through a vesicular transport system to regulate the function and morphology of target cells, thereby involving in a variety of biological processes, such as cell apoptosis or proliferation, and cytokine production. In the past decades, there are emerging evidence that exosomes play pivotal roles in the pathological mechanisms of several autoimmune diseases (ADs), including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), type 1 diabetes mellitus (T1DM), Sjogren's syndrome (SS), multiple sclerosis (MS), inflammatory bowel disease (IBD). systemic sclerosis (SSc), etc. Several publications have shown that exosomes are involved in the pathogenesis of ADs mainly through intercellular communication and by influencing the response of immune cells. The level of exosomes and the expression of nucleic acids can reflect the degree of disease progression and are excellent biomarkers for ADs. In addition, exosomes have the potential to be used as drug carriers thanks to their biocompatibility and stability. In this review, we briefly summarized the current researches regarding the biological functions of exosomes in ADs, and provided an insight into the potential of exosomes as biomarkers and therapeutic delivery for these diseases.

Diagnostic role of CXCL13 biomarker in primary Sjogren's syndrome patients with parotid non-Hodgkin's lymphoma complication

INTRODUCTION

Serum biomarkers are important predictive factors for development of parotid non-Hodgkin's lymphoma (NHL) complication in primary Sjogren's syndrome (pSS) patients. The aim was to evaluate the diagnostic accuracy of serum CXCL13 chemokine in pSS patients with parotid NHL complication.

MATERIAL AND METHODS

Serum CXCL13 chemokine was assessed in 33 patients with pSS [7 with parotid NHL complication (pSS+NHL subgroup) and 26 without NHL (pSS-NHL subgroup)] and 30 healthy subjects.

RESULTS

The serum CXCL13 levels in pSS+NHL subgroup [175.2 (107.9-220.4) pg/ml] were significantly higher comparing to the healthy subjects group (p=0.018) and the pSS-NHL subgroup (p=0.048). A cut-off value of 123.45pg/ml (Se=71.4%, Sp=80.8%, AUROC=0.747) was established for parotid lymphoma diagnosis.

CONCLUSION

The serum CXCL13 biomarker could be considered a valuable tool for the diagnosis of parotid NHL complication in pSS patients.

DLX6 and MSX1 from saliva samples as potential predictors of mandibular size: A cross-sectional study

INTRODUCTION

Morphologic features of the mandible are influenced by the genes of each individual. Mandible size is important to orthodontists because the mandible is the mechanism by which the lower face influences facial esthetics and dental function. To date, no biological marker has been identified that indicates eventual mandible size. This study aimed to correlate the expression of DLX5, DLX6, EDN1, HAND2, PRRX1, and MSX1 to mandible size.

METHODS

Fifty-nine orthodontic patients aged >6 years who had available cephalometric radiographs were studied. Patients were classified on the basis of condylion-to-gnathion measurements. Messenger RNA was isolated from saliva and subjected to real-time quantitative polymerase chain reaction.

RESULTS

Threshold cycle values for subjects with small mandibles (>1 standard deviation [SD] from the mean) had the least expression of DLX6 and MSX1. Threshold cycle values for subjects with large mandibles (>1 SD) had less expression of DLX6 and MSX1 than subjects within 1 SD but more than those with small mandibles.

CONCLUSIONS

DLX6 and MSX1 are related to mandible development and size. This finding could be used to improve treatment planning for medical and dental professionals seeking to understand the impact of genetics on bone growth.

Metabolic Profile of Whole Unstimulated Saliva in Patients with Sjögren’s Syndrome

(1) Background: Primary Sjögren’s Syndrome (pSS) is a multi-system autoimmune disease that involves the exocrine glands. Lymphocytes infiltrate the gland tissue, leading to anatomical modification and hypofunction. Even if the prognosis of pSS is favorable, quality of life is typically reduced due to the diverse manifestations of the disease. The aim of this study is to compare the salivary metabolomes of pSS with healthy controls (HCs). (2) Methods: Seven cases were selected from a cohort of pSS patients, and six age- and sex-matched HCs were recruited from a cohort of volunteers. Whole unstimulated saliva was collected for NMR analysis. Our metabolomic analysis focused on 360 ms total echo 1D 1H NMR CPMG spectra. Metabolites detected with CPMG NMR spectra were assigned through 2D NMR spectra (COSY, TOCSY, and HSQC). (3) Results: About 50 metabolites were detected and assigned. Unsupervised exploratory PCA returned partial clustering, and PLS-DA improved the separation between pSS and HCs, highlighting a pool of metabolites distinctly describing each group. (4) Conclusions: Despite the limited number of samples, the presented preliminary data are promising. PLS-DA indicated well-defined group separation, suggesting that the application of 1H-NMR metabolomics is suitable for the study of pSS.

Type 1 Diabetes Mellitus and Autoimmune Diseases: A Critical Review of the Association and the Application of Personalized Medicine

Type 1 Diabetes Mellitus (T1DM) is a common hyperglycemic disease characterized by the autoimmune destruction of insulin-producing beta cells of the pancreas. Various attempts have been made to understand the complex interplay of genetic and environmental factors which lead to the development of the autoimmune response in an individual. T1DM is frequently associated with other autoimmune illnesses, the most common being autoimmune thyroid disorders affecting more than 90% of people with T1D and autoimmune disorders. Antithyroid antibodies are present in around 20% of children with T1D at the start of the illness and are more frequent in girls. Patients with T1DM often have various other co-existing multi-system autoimmune disorders including but not limited to thyroid diseases, parathyroid diseases, celiac disease, vitiligo, gastritis, skin diseases, and rheumatic diseases. It is a consistent observation in clinics that T1DM patients have other autoimmune disorders which in turn affect their prognosis. Concomitant autoimmune illness might affect diabetes care and manifest itself clinically in a variety of ways. A thorough understanding of the complex pathogenesis of this modern-day epidemic and its association with other autoimmune disorders has been attempted in this review in order to delineate the measures to prevent the development of these conditions and limit the morbidity of the afflicted individuals as well. The measures including antibody screening in susceptible individuals, early identification and management of other autoimmune disorders, and adoption of personalized medicine can significantly enhance the quality of life of these patients. Personalized medicine has recently gained favor in the scientific, medical, and public domains, and is frequently heralded as the future paradigm of healthcare delivery. With the evolution of the ‘omics’, the individualization of therapy is not only closer to reality but also the need of the hour.

[Evaluation of morphological activity of primary Sjogren's syndrome on bioptates of minor salivary glands]

BACKGROUND

The results of the morphological study of the minor salivary glands can be used to assess the activity of the primary Sjogren's syndrome and to decide on adequate therapy.The existing protocol of The Sjögren's International Clinical Collaborative Alliance (SICCA) prescribes the methodology for examining biopsy specimens for suspected Sjögren's disease, however, experts interpret data from the analysis of histological preparations differently.

OBJECTIVE

To identify morphological forms of sialadenitis, as well as to determine the focus score in Russian patients based on the retrospective analysis of minor salivary glands biopsies of patients with primary Sjogren's syndrome.

MATERIAL AND METHODS

Biopsies of minor salivary glands were studied in 92 patients with primary Sjogren's syndrome and 42 patients without rheumatic disease.

RESULTS

Focal lymphocytic sialadenitis was detected in 69 patients with primary Sjogren's syndrome. The focus score in patients with primary Sjogren's syndrome was 7.32 (2.8-14.17). In patients without rheumatic diseases, this index was 0.48 (p<0.05). Patients with confluent lymphocytic foci need immunohistochemical examination and dynamic monitoring to exclude lymphoproliferative diseases.

CONCLUSION

The index of morphological activity of sialadenitis in primary Sjogren's syndrome ranges from 2.8 to 14.17 and reflects the activity of the underlying disease.It should be taken into account in the diagnosis and prescription of adequate therapy. Further study of the correlations of morphological and clinical and laboratory parameters will lead to clarification of the criterion signs of the disease.

Pathogenesis and treatment of Sjogren's syndrome: Review and update

Sjogren's syndrome (SS) is a chronic autoimmune disease accompanied by multiple lesions. The main manifestations include dryness of the mouth and eyes, along with systemic complications (e.g., pulmonary disease, kidney injury, and lymphoma). In this review, we highlight that IFNs, Th17 cell-related cytokines (IL-17 and IL-23), and B cell-related cytokines (TNF and BAFF) are crucial for the pathogenesis of SS. We also summarize the advances in experimental treatment strategies, including targeting Treg/Th17, mesenchymal stem cell treatment, targeting BAFF, inhibiting JAK pathway, et al. Similar to that of SLE, RA, and MS, biotherapeutic strategies of SS consist of neutralizing antibodies and inflammation-related receptor blockers targeting proinflammatory signaling pathways. However, clinical research on SS therapy is comparatively rare. Moreover, the differences in the curative effects of immunotherapies among SS and other autoimmune diseases are not fully understood. We emphasize that targeted drugs, low-side-effect drugs, and combination therapies should be the focus of future research.