Sjögren syndrome

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.

Impact of Reduced Saliva Production on Intestinal Integrity and Microbiome Alterations: A Sialoadenectomy Mouse Model Study

This study investigates the effect of reduced saliva production on intestinal histological structure and microbiome composition using a sialoadenectomy murine model, evaluating differences in saliva secretion, body weight, intestinal histopathological changes, and microbiome alteration using 16S rRNA gene sequencing across three groups (control, sham, and sialoadenectomy). For statistical analysis, one-way analysis of variance and multiple comparisons using Bonferroni correction were performed. p-values < 0.05 were considered statistically significant. Microbiome analysis was performed using Qiime software. The results show that reduced saliva secretion leads to structural changes in the intestinal tract, including shorter and atrophic villi, deformed Paneth cells, decreased goblet cell density, and immunohistochemical changes in epidermal growth factor and poly(ADP-ribose) polymerase-1, especially at three months after surgery. They also showed significant alterations in the intestinal microbiome, including increased Lactobacillaceae and altered populations of Ruminococcaceae and Peptostreptococcaceae, suggesting potential inflammatory responses and decreased short-chain fatty acid production. However, by 12 months after surgery, these effects appeared to be normalized, indicating potential compensatory mechanisms. Interestingly, sham-operated mice displayed favorable profiles, possibly due to immune activation from minor surgical intervention. This study underscores saliva's essential role in intestinal condition, emphasizing the "oral-gut axis" and highlighting broader implications for the relationship between oral and systemic health.

Associations Between Interleukin-10 Polymorphisms and Susceptibility to Sjögren's Syndrome: A Meta-Analysis

This study sought to investigate the association between interleukin-10 (IL10) polymorphisms and susceptibility to Sjögren's syndrome. A systematic search of the Medline, Embase and Web of Science databases was conducted to identify relevant articles from inception to April 2024. No restrictions were placed on race, ethnicity or geographic area, but only studies published in English were included. A meta-analysis was conducted to evaluate the association among the IL10-1082 G/A (rs1800896), -819 C/T (rs1800871) and -592 C/A (rs1800872) polymorphisms, as well as their haplotypes and the risk of developing Sjögren's syndrome. The included studies involved 998 Sjögren's syndrome patients and 1576 controls. Ten studies were included in the meta-analysis. Meta-analysis of the IL10-1082 G/A polymorphism revealed no significant association with Sjögren's syndrome (odds ratio [OR] = 1.115, 95% confidence interval [CI]: 0.888-1.401, p = 0.343), with stratification by ethnicity yielding consistent results for Europeans and Latin Americans. Similarly, the IL10-819 C/T polymorphism was not associated with Sjögren's syndrome in any study subjects (OR = 0.859, 95% CI: 0.648-1.138, p = 0.290). The IL10-592 C allele also exhibited no association with Sjögren's syndrome (OR = 1.131, 95% CI: 0.776-1.646, p = 0.522). However, the GCC carrier status demonstrated a significant association with Sjögren's syndrome across all study subjects (OR = 1.496, 95% CI: 1.200-1.865, p < 0.001), particularly in Europeans (OR = 1.444, 95% CI: 1.085-1.921, p = 0.012) and Latin Americans (OR = 1.324, 95% CI: 1.115-2.366, p = 0.012). A significant protective effect of the homozygous ATA/ATA haplotype on Sjögren's syndrome was found in Europeans (OR = 0.320, 95% CI: 0.121-0.846, p = 0.022). This meta-analysis indicates a significant link between carrying the GCC haplotype of the IL10-1082 G/A, -819 C/T and -592 C/A polymorphisms and an increased susceptibility to Sjögren's syndrome. Conversely, the homozygous ATA/ATA haplotype appears to confer protection against the risk of Sjögren's syndrome, particularly in European populations.

Associations between Sjogren syndrome and psychiatric disorders in European populations: a 2-sample bidirectional Mendelian randomization study

Background

Psychiatric disorders, such as major depressive disorder (MDD), anxiety disorder (AD), bipolar disorder (BD), and schizophrenia (SCZ), are disturbances in brain activity that lead to disorders of cognition, behavior, and emotion regulation. Among Sjogren syndrome (SS) patients, psychiatric disorders are more prevalent than in the general population. Identifying associated risk factors can provide new evidence for clinical diagnosis and treatment.

Methods

We selected genetic instruments based on published genome-wide association studies (GWASs) to determine predisposition. Then, we conducted a 2-sample bidirectional Mendelian randomization (MR) analysis to explore the potential causal associations between SS and four major psychiatric disorders. The primary analysis was performed using MR with the inverse-variance weighted method. Confirmation was achieved through Steiger filtering and testing to determine the causal direction. Sensitivity analyses were conducted using MR-Egger, MR-PRESSO, and "leave-one-out" method methods.

Results

Our study showed that SS was linked to BD and SCZ, indicating that individuals with SS may have a reduced risk of developing BD (IVW: OR = 0.940, P=0.014) and SCZ (IVW: OR = 0.854, P=1.47*10-4), while there was no causal relationship between SS and MDD or AD. MR-Egger regression shows no evidence of pleiotropy (BD: intercept = 0.007, p = 0.774; SCZ: intercept = 0.051, p = 0.209). The same as the MR-PRESSO analysis (BD: global test p = 1.000; SCZ: global test p = 0.160). However, the results from the leave-one-out analysis demonstrated instability. Specifically, after excluding SNP rs3117581, the effects on BD and SCZ were found to be non-significant, suggesting the potential influence of unrecognized confounding factors. The results of the reverse MR show that four major psychiatric disorders had no causal effects on SS.

Conclusions

Our research findings demonstrate a causal relationship between SS and SCZ, as well as between SS and BD. There are no causal effects between the four major psychiatric disorders and SS. These findings suggest that SS may have the potential to reduce the risk of both psychiatric disorders. This study provides new insight for their prevention and treatment.

A Review of the Tear Film Biomarkers Used to Diagnose Sjogren's Syndrome

This literature review looks at Sjogren's Syndrome (SS), a chronic autoimmune disorder affecting exocrine glands, particularly the lacrimal and salivary glands. SS manifests as ocular and oral dryness, with severe complications like visual dysfunction and corneal perforation, as well as systemic implications, such as interstitial lung disease and lymphoma. This review explores the use of tear film biomarkers to diagnose SS, emphasizing the significance of their identification in aiding clinical diagnosis and differentiation from other diseases. This study identified and analyzed 15 papers, encompassing 1142 patients and employing various tear sample collection methods. Tear biomarkers were categorized by function and explored in-depth. Categories include (1) antimicrobials, antivirals, and antifungals; (2) components of immune regulation; (3) components that regulate metabolic processes; and (4) inflammatory markers. Noteworthy findings include the potential diagnostic values of tear lysozyme, lactoferrin, dinucleoside polyphosphates, cathepsin, defensin, antibodies, epidermal fatty acid-binding protein, HLA-DR, ADAM10, aquaporin 5, and various miRNAs and mRNAs. Overall, our understanding of SS tear film composition is enhanced, providing valuable insights into the pathogenesis of SS and offering a foundation for future diagnostic and therapeutic advancements in autoimmune conditions affecting the ocular surface.

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.

VNN2-expressing circulating monocytes exhibit unique functional characteristics and are decreased in patients with primary Sjögren's syndrome

OBJECTIVE

This study aims to elucidate the significance of VNN2 expression in peripheral blood monocytes and its clinical relevance in primary Sjögren's syndrome (pSS).

METHODS

We investigated VNN2 expression by analyzing single-cell RNA sequencing (scRNA-seq) data from peripheral blood mononuclear cells. Flow cytometry was used to detect and compare VNN2 expression in total monocytes, classical monocytes (cMo), intermediate monocytes (iMo) and non-classical monocytes (ncMo). Additionally, we examined the expression of HLA, ICAM1, CD62L, ITGAM, S100A8, S100A9, CCR2, CCR6, CX3CR1 and CXCR3 in VNN2+ and VNN2- cells. We analyzed the correlation between VNN2 expression and clinical indicators and assessed the clinical utility of VNN2+ monocytes in pSS diagnosis using receiver operating characteristic curves.

RESULTS

We observed high VNN2 expression in monocytes, with significantly higher levels in CD14++ monocytes compared to ncMo. VNN2+ monocytes exhibited decreased expression of HLA and CD62L and increased expression of ICAM1, ITGAM, S100A8, S100A9, CCR2, CCR6, CX3CR1 and CXCR3 compared to VNN2- monocytes. Although scRNA-seq data showed that VNN2 mRNA was upregulated, cell surface expression of VNN2 was decreased in monocytes from pSS patients compared to healthy controls. The reduced levels of VNN2+ monocyte subpopulations in pSS patients were negatively correlated with anti-ribosome antibody levels and positively correlated with complement 4 levels. Detection of VNN2 expression in monocytes can aid in the auxiliary diagnosis of pSS.

CONCLUSION

Monocytes expressing cell surface VNN2 are significantly reduced in pSS patients. This suggests a potential role for VNN2 in pSS development and its potential use as a diagnostic marker for pSS.

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.

[Fever in rheumatological diseases]

Fever is a frequent and important symptom in patients with rheumatological diseases and can be an expression of activity of the underlying rheumatological disease. There is great variability in the incidence of fever as a symptom of the disease between individual diseases. The growing understanding of the molecular signatures of the diseases can help to explain these discrepancies: A genetic overactivation of potently pyrogenic cytokines is the reason why fever is nearly always present in autoinflammatory syndromes. In contrast, fever is less common in polyarthritis and myositis and mostly limited to severe courses of disease. In the diagnostic work-up of fever, frequent differential diagnoses, such as infections, malignancies, side effects of drugs and hypersensitivity reactions should be considered. This article provides an overview of the physiology of the development of fever, describes the relevance of fever in individual rheumatological diseases and proposes a workflow for the clinical clarification of rheumatological patients who present with fever.

KLRB1 defines an activated phenotype of CD4+ T cells and shows significant upregulation in patients with primary Sjögren's syndrome

OBJECTIVE

This study aimed to investigate the role of KLRB1 (CD161) in human CD4+ T cells and elucidate its significance in primary Sjögren's syndrome (pSS).

METHODS

Peripheral blood samples from 37 healthy controls and 44 pSS patients were collected. The publicly available single-cell RNA-Seq data from pSS patient PBMCs were utilized to analyse KLRB1 expression in T cells. KLRB1-expressing T lymphocyte subset proportions in pSS patients and healthy controls were determined by flow cytometry. CD25, Ki-67, cytokine secretion, and chemokine receptor expression in CD4+ KLRB1+ T cells were detected and compared with those in CD4+ KLRB1- T cells. Correlation analysis was conducted between KLRB1-related T-cell subsets and clinical indicators. ROC curves were generated to explore the diagnostic potential of KLRB1 for pSS.

RESULTS

KLRB1 was significantly upregulated following T-cell activation, and Ki-67 and CD25 expression was significantly greater in CD4+ KLRB1+ T cells than in CD4+ KLRB1- T cells. KLRB1+ CD4+ T cells exhibited greater IL-17A, IL-21, IL-22, and IFN-γ secretion upon stimulation, and there were significantly greater proportions of CCR5+, CCR2+, CX3CR1+, CCR6+, and CXCR3+ cells among CD4+ KLRB1+ T cells than among CD4+ KLRB1- T cells. Compared with that in HCs, KLRB1 expression in CD4+ T cells was markedly elevated in pSS patients and significantly correlated with clinical disease indicators.

CONCLUSION

KLRB1 is a characteristic molecule of the CD4+ T-cell activation phenotype. The increased expression of KLRB1 in the CD4+ T cells of pSS patients suggests its potential involvement in the pathogenesis of pSS and its utility as an auxiliary diagnostic marker for pSS.

The role of orexin in fatigue and sleep quality in patients with primary Sjögren's syndrome

BACKGROUND

Sleep disorders and fatigue are prevalent symptoms affecting primary Sjögren's syndrome (pSS) patients. This study aimed to assess the sleep quality of pSS patients as well as its relationship to fatigue and orexin level.

METHODS

This is a cross-sectional study evaluating fatigue in pSS using the Fatigue Severity Scale (FSS). Sleep quality was evaluated using the Pittsburg Sleep Quality Index (PSQI). The European Alliance of Associations for Rheumatology (EULAR) Sjögren's Syndrome Disease Activity Index (ESSDAI) and EULAR Sjögren's Syndrome Patient-Reported Index (ESSPRI) were calculated.

RESULTS

Forty-one patients met the sample criteria and were involved in the final report. They were all females, with a mean (± SD) age and median disease duration of 40.87 ± 10.84 and 36 (6-180) months, respectively. The mean ESSDAI was 0.92 ± 1.3, while the mean ESSPRI was 5.8 ± 2.13. Based on the FSS, 32 (78.04%) patients had a positive test with a mean score of 5.07 ± 1.54. The total PSQI score showed that 60.97% had poor sleep, and the orexin level was lower in patients with pSS than in healthy controls. There was no correlation between orexin level and the presence of fatigue nor the PSQI score.

CONCLUSION

In conclusion, serum orexin levels were lower in patients with pSS than healthy controls, It could be related to impairments in sleep and fatigue in patients with pSS.

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 and immunological features of primary Sjögren's syndrome patients with positive anti-centromere protein B antibody]

OBJECTIVE

To investigate the clinical and immunological features of primary Sjögren's syndrome (pSS) patients with positive anti-centromere protein B (CENP-B) antibody.

METHODS

In this cross-sectional study, the general clinical data, radiographic examination and labial salivary gland biopsy data, and serum immunological and biochemical data of patients diagnosed with pSS from January 2016 to August 2022 were evaluated. The included patients were divided into the anti-CENP-B antibody positive and negative groups. Intergroup differences were analyzed with SPSS 23.0 software. Subgroup analysis was further performed by dividing the anti-CENP-B antibody positive group into the single anti-CENP-B antibody positive and with other auto-antibodies positive groups to determine the characters related to anti-CENP-B antibody.

RESULTS

In this study, 288 patients with pSS were evaluated, including 75 patients with anti-CENP-B antibody positive and 213 with anti-CENP-B antibody negative. Univariate analysis showed that compared with the anti-CENP-B antibody negative group, the patients of the anti-CENP-B antibody positive group were older, had lower proportion of the patients with salivary gland enlargement and higher proportion of autoimmune liver disease. As for immunological indicators, the positive proportions of anti-SSA/Ro60, anti-Ro52, and anti-SSB antibodies were significantly lower. Moreover, the immunoglobulin (Ig) G and rheumatoid factor levels were significantly lower, while the IgM level was significantly higher in the patients of the anti-CENP-B antibody positive group. As for serum biochemical indicators, for the patients of the anti-CENP-B antibody positive group, the level of total protein (TP) was lower, the albumin/globulin ratio was higher, and the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), lactate dehydrogenase (LDH) were higher. Subgroup analysis showed that the levels of TP and IgA in the patients of the single anti-CENP-B antibody positive group were significantly lower than those of the patients with other autoantibodies positive group.

CONCLUSION

The pSS patients with anti-CENP-B antibody positive have unique clinical and immunological features of lower disease activity, less likely to involve salivary gland, higher risk for autoimmune liver disease, and higher levels of liver function indicators. Anti-CENP-B antibody may be a marker for a distinct subset of polyautoimmunity in Sjögren's syndrome.

Ultrasound abnormalities of the major salivary glands in Egyptian patients with systemic sclerosis

INTRODUCTION/OBJECTIVES

systemic sclerosis (SSc) is an autoimmune disorder with multiple organs destruction. This study aimed to identify the ultrasonographic changes of major salivary glands in Egyptian scleroderma patients and to detect their association to different disease manifestations.

METHODS

Forty-seven SSc patients and 43 apparent healthy volunteers were enrolled. Demographics, inflammatory markers, and autoimmune status were recorded. Ultrasound evaluation of salivary glands was performed. Salivary gland changes' associations were statistically examined with SSc susceptibility and disease manifestations.

RESULTS

Thirty-one SSc patients exhibited glandular pathology (p < 0.0001), compared to controls. Of these abnormalities, SSc patients showed a total parotid gray scale of 2, total submandibular gray scale of 2, total glandular gray scale of 4, and total glandular Doppler signal of 1 at p < 0.0001, compared to the control group. Patients with SSc and glandular pathology had a higher prevalence of arthritis (p = 0.029) and ESR (p = 0.002) than those with normal glandular ultrasound. Significant associations were reported between gray scale ultrasound (GSUS) of total parotid (odds ratio "OR" = 0.4), total submandibular (OR = 0.36), and total glandular (OR = 0.53) with susceptibility to SSc at p < 0.0001. Total glandular GSUS (p = 0.039) and total submandibular power Doppler (p = 0.044) correlated with the SSc duration. Total parotid GSUS (p = 0.008) and total glandular GSUS (p < 0.0001) correlated with Schirmer's test.

CONCLUSIONS

Major salivary glands are affected in SSc. Hence, scanning these glands with ultrasound is an additive tool besides the current practice. Key Points • Major salivary gland changes, observed by ultrasonography, are new findings in Egyptian SSc patients. • Ultrasound changes of major salivary glands are associated with inflammatory markers and clinical manifestations of SSc. • Scleroderma ultrasonography scans of the main salivary glands could be added to the routine work.

Autoimmune Disease-Related Dry Eye Diseases and Their Placement Under the Revised Classification Systems: An Update

Dry eye disease (DED) is a chronic and progressive disorder involving the ocular surface, characterized by disturbances in tear film composition, instability of the tear film, and inflammation of the ocular surface. There are two forms of DED: aqueous-deficient dry eye (ADDE) and evaporative dry eye (EDE). Autoimmune diseases are systemic disorders involving multiple organs, including the eyes, and have a significant impact on DED. There have been multiple studies demonstrating the relation between autoimmune diseases and DED. This article reviews the current knowledge regarding the epidemiological characteristics, pathogenesis, and treatments of autoimmune disease-related DED.

The role of inflammation in autoimmune disease: a therapeutic target

Autoimmune diseases (AIDs) are immune disorders whose incidence and prevalence are increasing year by year. AIDs are produced by the immune system's misidentification of self-antigens, seemingly caused by excessive immune function, but in fact they are the result of reduced accuracy due to the decline in immune system function, which cannot clearly identify foreign invaders and self-antigens, thus issuing false attacks, and eventually leading to disease. The occurrence of AIDs is often accompanied by the emergence of inflammation, and inflammatory mediators (inflammatory factors, inflammasomes) play an important role in the pathogenesis of AIDs, which mediate the immune process by affecting innate cells (such as macrophages) and adaptive cells (such as T and B cells), and ultimately promote the occurrence of autoimmune responses, so targeting inflammatory mediators/pathways is one of emerging the treatment strategies of AIDs. This review will briefly describe the role of inflammation in the pathogenesis of different AIDs, and give a rough introduction to inhibitors targeting inflammatory factors, hoping to have reference significance for subsequent treatment options for AIDs.

Prevalence and Clinical Implications of Scleroderma-Specific Autoantibodies in Seronegative Patients with Sicca Complaints

Introduction

Previous studies have revealed the presence of anticentromere antibodies in patients with Sjögren's syndrome (SS), predominantly in those serologically negative for antibodies against Ro/SSA and La/SSB antigens (seronegative). The prevalence and clinical significance of specific autoantibodies for Systemic Sclerosis (SSc) in seronegative patients with sicca complaints (dry eyes, dry mouth) have not yet been studied.

Aim of the study

Investigate the prevalence and clinical significance of SSc-specific autoantibodies in seronegative patients with sicca complaints.

Methods

Among 212 patients with sicca symptoms that were investigated at the Laboratory of Physiology, Medical School of Athens, National and Kapodistrian University of Athens between the years 2017-2020 for the presence of antibodies against Ro/SSA and La/SSB antigens, we found 106 patients that did not meet the criteria for SS following a thorough investigation. We have already performed serological tests of 13 specific autoantibodies for Scleroderma by using the test EUROLINE Systemic Sclerosis (Nucleoli) profile (IgG) (EUROIMMUNE Medizinische Labordiagnostika AG) in 51 of these patients. Additionally, their demographic, clinical, and laboratory data have been recorded.

Results

The presence of the specific SSc-specific autoantibodies was noticed in 29/51 patients (57%). More precisely, in 7/29 patients (24%) we recorded NOR90 as well as Th/To, in 5/29 (17%) Ku & Ro52, in 4/29 (14%) CENP-B, in 3/29 (10%) CENP-A & RP155, in 2/29 (7%) RP11 & PM/Scl 75 and finally in 1/29 (3.5%) Scl70, PM/Scl 100 & Fibrillarin respectively. The subsequent follow-up of these patients revealed signs of pulmonary hypertension and interstitial lung disease in some cases.

Conclusions

The high prevalence of Scleroderma-specific autoantibodies in seronegative sicca patients discloses those needing tighter follow-up and systematic treatment.

The developing role of extracellular vesicles in autoimmune diseases: special attention to mesenchymal stem cell-derived extracellular vesicles

Autoimmune diseases are complex, chronic inflammatory conditions initiated by the loss of immunological tolerance to self-antigens. Nowadays, there is no effective and useful therapy for autoimmune diseases, and the existing medications have some limitations due to their nonspecific targets and side effects. During the last few decades, it has been established that mesenchymal stem cells (MSCs) have immunomodulatory functions. It is proposed that MSCs can exert an important therapeutic effect on autoimmune disorders. In parallel with these findings, several investigations have shown that MSCs alleviate autoimmune diseases. Intriguingly, the results of studies have demonstrated that the effective roles of MSCs in autoimmune diseases do not depend on direct intercellular communication but on their ability to release a wide spectrum of paracrine mediators such as growth factors, cytokines and extracellular vehicles (EVs). EVs that range from 50 to 5,000 nm were produced by almost any cell type, and these nanoparticles participate in homeostasis and intercellular communication via the transfer of a broad range of biomolecules such as modulatory proteins, nucleic acids (DNA and RNA), lipids, cytokines, and metabolites. EVs derived from MSCs display the exact properties of MSCs and can be safer and more beneficial than their parent cells. In this review, we will discuss the features of MSCs and their EVs, EVs biogenesis, and their cargos, and then we will highlight the existing discoveries on the impacts of EVs from MSCs on autoimmune diseases such as multiple sclerosis, arthritis rheumatic, inflammatory bowel disease, Type 1 diabetes mellitus, systemic lupus erythematosus, autoimmune liver diseases, Sjögren syndrome, and osteoarthritis, suggesting a potential alternative for autoimmune conditions therapy.

Lactate-induced mtDNA Accumulation Activates cGAS-STING Signaling and the Inflammatory Response in Sjögren's Syndrome

Acinar epithelial cell atrophy in secretory glands is a hallmark of primary Sjögren's syndrome (pSS), the cause of which is far from elucidated. We examined the role of acinar atrophy by focusing on the metabolism of glandular epithelial cells and mitochondria in the pSS environment. After confirming the presence of a high-lactate environment in the labial glands of human pSS patients, we used the A253 cell line and NOD/Ltj mice as models to investigate the metabolic changes in salivary gland epithelial cells in a high-lactate environment in vitro and in vivo. We found that epithelial cells produced high levels of IL-6, IL-8, IFN-α, IFN-β and TNF-α and exhibited significant NF-κB and type I IFN-related pathway activation. The results confirmed that lactate damaged mitochondrial DNA (mtDNA) and led to its leakage, which subsequently activated the cGAS-STING pathway. Inflammatory cytokine production and pathway activation were inhibited in vivo and in vitro by the lactate scavenger sodium dichloroacetate (DCA). Our study provides new insights into the etiology and treatment of pSS from the perspective of cell metabolism.

Rapidly Enlarging Parotid Mass in a Person Living with HIV: A Case of Multiple Myeloma with Extramedullary Plasmacytoma

BACKGROUND The differential diagnosis for a parotid mass is broad, including infectious, autoimmune, and neoplastic etiologies. In people with HIV, regardless of viral suppression or immune status, neoplastic causes are more common. This report describes the evaluation of a woman with a large parotid mass, with an ultimate diagnosis of multiple myeloma with extramedullary plasmacytoma. CASE REPORT A 51-year-old woman with HIV infection presented with headache, weight loss, and right facial mass that was present for 5 years but more rapidly enlarging in the prior year. CD4 count was 234 cells/mL, and HIV RNA was 10 810 copies/mL. Physical examination was significant for a large deforming right-sided facial mass, decreased sensation in the V1 and V2 distributions, and right-sided ophthalmoplegia and ptosis. MRI and PET/CT scan confirmed a metabolically active large parotid mass with extension into the cavernous sinus. An IgG kappa monoclonal spike was present on serum protein electrophoresis. Incisional biopsy of the facial mass showed atypical lymphoid cells with plasmablastic and plasmacytic morphology with a high mitotic rate and proliferation index. She was diagnosed with R-ISS stage II IgG kappa multiple myeloma with extramedullary plasmacytoma, and initiated on chemotherapy, radiation, and antiretroviral therapy. CONCLUSIONS A rapidly enlarging parotid mass should prompt timely evaluation and biopsy for definitive diagnosis, particularly in immunocompromised patients, including people with HIV. Extramedullary plasmacytomas have a more aggressive disease process in people with HIV and are associated with high-risk multiple myeloma and progression, as seen in this patient.

Regulatory Mechanism of M1/M2 Macrophage Polarization in the Development of Autoimmune Diseases

Macrophages are innate immune cells in the organism and can be found in almost tissues and organs. They are highly plastic and heterogeneous cells and can participate in the immune response, thereby playing a crucial role in maintaining the immune homeostasis of the body. It is well known that undifferentiated macrophages can polarize into classically activated macrophages (M1 macrophages) and alternatively activated macrophages (M2 macrophages) under different microenvironmental conditions. The directions of macrophage polarization can be regulated by a series of factors, including interferon, lipopolysaccharide, interleukin, and noncoding RNAs. To elucidate the role of macrophages in various autoimmune diseases, we searched the literature on macrophages with the PubMed database. Search terms are as follows: macrophages, polarization, signaling pathways, noncoding RNA, inflammation, autoimmune diseases, systemic lupus erythematosus, rheumatoid arthritis, lupus nephritis, Sjogren's syndrome, Guillain-Barré syndrome, and multiple sclerosis. In the present study, we summarize the role of macrophage polarization in common autoimmune diseases. In addition, we also summarize the features and recent advances with a particular focus on the immunotherapeutic potential of macrophage polarization in autoimmune diseases and the potentially effective therapeutic targets.

Chronic Epstein-Barr virus infection: A potential junction between primary Sjögren's syndrome and lymphoma

Primary Sjögren's syndrome (pSS) is an autoimmune disease that targets exocrine glands, leading to exocrine dysfunction. Due to its propensity to infect epithelial and B cells, Epstein-Barr virus (EBV) is hypothesized to be related with pSS. Through molecular mimicry, the synthesis of specific antigens, and the release of inflammatory cytokines, EBV contributes to the development of pSS. Lymphoma is the most lethal outcome of EBV infection and the development of pSS. As a population-wide virus, EBV has had a significant role in the development of lymphoma in people with pSS. In the review, we will discuss the possible causes of the disease.

The Autoimmune Rheumatic Disease Related Dry Eye and Its Association with Retinopathy

Dry eye disease is a chronic disease of the ocular surface characterized by abnormal tear film composition, tear film instability, and ocular surface inflammation, affecting 5% to 50% of the population worldwide. Autoimmune rheumatic diseases (ARDs) are systemic disorders with multi-organ involvement, including the eye, and play a significant role in dry eye. To date, most studies have focused on Sjögren's syndrome (one of the ARDs) since it manifests as two of the most common symptoms-dry eyes and a dry mouth-and attracts physicians to explore the relationship between dry eye and ARDs. Many patients complained of dry eye related symptoms before they were diagnosed with ARDs, and ocular surface malaise is a sensitive indicator of the severity of ARDs. In addition, ARD related dry eye is also associated with some retinal diseases directly or indirectly, which are described in this review. This review also summarizes the incidence, epidemiological characteristics, pathogenesis, and accompanying ocular lesions of ARD's related dry eye, emphasizing the potential role of dry eye in recognition and monitoring among ARDs patients.

Ocular microvascular alteration in Sjögren's syndrome treated with hydroxychloroquine: an OCTA clinical study

Background

Sjögren's syndrome (SjS) is a rare autoimmune disease, and despite our knowledge of SjS, we still lack effective treatments. Chloroquine drugs used to treat autoimmune diseases are still the primary medicine for SjS but increase the risk of chloroquine retinopathy.

Objectives

The objective of this study is to use Optical Coherence Tomography Angiography (OCTA) images to monitor the microvascular changes in the fundus of SjS patients after hydroxychloroquine (HCQ) treatment and the feasibility of using them as diagnostic indicators.

Design

This is a retrospective observational cohort study.

Methods

Twelve healthy controls (HCs group; 24 eyes), 12 SjS patients (SjS group; 24 eyes), and 12 SjS patients treated with HCQ (HCQ group; 24 eyes) were recruited. Three-dimensional OCTA images of the retina were collected, and microvascular density was calculated for each eye. OCTA image segmentation for analysis was conducted using the central wheel division method (C1-C6), hemisphere segmentation method (SR, SL, IL, and IR), and the early treatment of diabetic retinopathy study method (ETDRS) (R, S, L, and I).

Results

Retinal microvascular density was significantly lower in the SjS patients compared to the HCs group (p < 0.05) and much lower in the HCQ group compared to the SjS patients (p < 0.05). The SjS and HCQ groups differed in the I, R, SR, IL, and IR regions in the superficial and deep retina and the S region in the superficial retina. The ROC curves of the relationship between the HCs and SjS groups and between the SjS and HCQ groups demonstrated good classification accuracy.

Conclusion

HCQ may contribute significantly to the microvascular alteration in SjS. Microvascular alteration is a potential marker with adjunctive diagnostic value. The MIR and the OCTA images of I, IR, and C1 regions showed high accuracy in minoring the alteration.

Multiple fibrotic lung nodules in a patient with primary Sjögren's syndrome

Evaluation of bilateral lung nodules noted on imaging poses a diagnostic challenge to clinicians as it can have many differentials from benign to malignant causes. It becomes especially critical to identify them right when there are underlying autoimmune conditions and risk factors for infection. However, a thorough investigation can lead to the recognition of rare associations as described below. We present here a 57-year-old woman who was admitted to the hospital with shortness of breath. Imaging with a computed tomography (CT) scan showed that she had 8 bilateral cystic pulmonary nodules with focal areas of ground-glass opacity and mediastinal lymphadenopathy. Fibrobronchoscopy and histopathological studies were done on the right middle lobe lung nodule demonstrated that the lung nodule was fibrotic with reactive inflammation but showed no malignant cells. Upon further detailed history and chart review, it was noted that the patient had a history of dry eyes leading to an autoimmune workup showing positive antinuclear antibodies (ANA), anti-Ro, and anti-La antibodies with no follow-up since then. This lead to the suspicion that these nodules could be related to underlying Sjögren's syndrome. Initial inpatient management with intravenous steroids showed significant improvement in her symptomatology. Hence, we present this rare association of lung nodules with Sjögren's syndrome and its management for awareness of this condition.

The dual role of fucosidases: tool or target

Regular intake of fucosylated oligosaccharides has been associated with several benefits for human health, particularly for new-borns. Since these biologically active molecules can be found naturally in human milk, research efforts have been focused on the alternative synthetic routes leading to their production. In particular, utilization of fucosidases to perform stereoselective transglycosylation reactions has been widely investigated. Other reasons that bring these enzymes to the spotlight are their role in viral infections and cancer proliferation. Since their involvement in the pathogenesis of these diseases have been widely described, fucosidases have become a target in newly developed therapies. Finally, activity disorders of biologically important fucosidases can lead to health problems such as fucosidosis. What is common for both mechanisms is the interaction between the enzyme and substrates in and around the active site. Therefore, this review will analyse different substrate structures that have been tested in terms of their interaction with fucosidases active sites, either in synthesis or inhibition reactions. The published results will be compared from this perspective.

Aberrant signaling of immune cells in Sjögren’s syndrome patient subgroups upon interferon stimulation

Background

Primary Sjögren’s syndrome (pSS) is a systemic autoimmune disease, characterized by mononuclear cell infiltrates in the salivary and lacrimal glands, leading to glandular atrophy and dryness. Patient heterogeneity and lack of knowledge regarding its pathogenesis makes pSS a difficult disease to manage.

Methods

An exploratory analysis using mass cytometry was conducted of MAPK/ERK and JAK/STAT signaling pathways in peripheral blood mononuclear cells (PBMC) from 16 female medication free pSS patients (8 anti-Sjögren’s syndrome-related antigen A negative/SSA- and 8 SSA+) and 8 female age-matched healthy donors after stimulation with interferons (IFNs).

Results

We found significant differences in the frequencies of memory B cells, CD8+ T central and effector memory cells and terminally differentiated CD4+ T cells among the healthy donors and patient subgroups. In addition, we observed an upregulation of HLA-DR and CD38 in many cell subsets in the patients. Upon IFNα2b stimulation, slightly increased signaling through pSTAT1 Y701 was observed in most cell types in pSS patients compared to controls, while phosphorylation of STAT3 Y705 and STAT5 Y694 were slightly reduced. IFNγ stimulation resulted in significantly increased pSTAT1 Y701 induction in conventional dendritic cells (cDCs) and classical and non-classical monocytes in the patients. Most of the observed differences were more prominent in the SSA+ subgroup, indicating greater disease severity in them.

Conclusions

Augmented activation status of certain cell types along with potentiated pSTAT1 Y701 signaling and reduced pSTAT3 Y705 and pSTAT5 Y694 induction may predispose pSS patients, especially the SSA+ subgroup, to upregulated expression of IFN-induced genes and production of autoantibodies. These patients may benefit from therapies targeting these pathways.

Ruscogenin Ameliorated Sjögren's Syndrome by Inhibiting NLRP3 Inflammasome Activation

This article investigated the role and the specific mechanism of Ruscogenin in Sjögren's syndrome (SS). NOD/ShiLtJ mice were treated with Ruscogenin, and acinar cells isolated from submandibular glands were treated with TNF-α, Ruscogenin and transfected with NLRP3 overexpression plasmid. Salivary flow rate (SFR) was measured at weeks 11, 13, 15, 17, and 20. Histological analysis of the submandibular glands was conducted by hematoxylin-eosin staining assay. IL-6, IL-17, TNF-α, and IL-1β mRNA expression was detected through qRT-PCR. AQP 5, AQP 4, P2X7R, NLRP3, caspase 1, IL-1β, Bax, and Bcl-2 protein levels were tested by western blot. Cell apoptosis was assessed through acridine orange and propidium iodide (AO/PI) staining assay and flow cytometry assay. Ruscogenin ameliorated the SFR and submandibular gland inflammation of NOD/ShiLtJ mice. Ruscogenin promoted the preservation of acinar cells and suppressed inflammation-related factors (P2X7R, NLRP3, caspase 1, and IL-1β) in submandibular gland tissues of NOD/ShiLtJ mice. Ruscogenin inhibited acinar cell apoptosis in NOD/ShiLtJ mice and reversed TNF-α-induced apoptosis and inflammation of acinar cells. NLRP3 overexpression reversed the repressive effect of Ruscogenin on TNF-α-induced inflammation and apoptosis of acinar cells. Ruscogenin ameliorated SS by inhibiting NLRP3 inflammasome activation.

Sirolimus therapy restores the PD-1+ICOS+Tfh:CD45RA-Foxp3high activated Tfr cell balance in primary Sjögren's syndrome

BACKGROUND

Primary Sjögren's syndrome (pSS) is a common chronic autoimmune disease characterized by lymphocytic infiltration of salivary and lacrimal glands. The current study was performed to investigate the roles of follicular helper T (Tfh) and follicular regulatory T (Tfr) subsets in patients with pSS, and to evaluate the effects of sirolimus on these cells.

METHODS

Levels of circulating Tfh and Tfr subsets in 58 pSS patients and 26 healthy controls (HC) were determined by flow cytometry. These T cell subsets were also analyzed in 12 patients before and after treatment with sirolimus. Clinical features and correlations with follicular T cells were analyzed systematically. The discriminative ability of the cells and ratios was evaluated based on the area under the receiver operating characteristic curves.

RESULTS

Patients with pSS had higher percentage and absolute number of PD-1+ICOS+Tfh cells, while lower percentage and absolute number of Tfr, activated regulatory T (aTreg) cells, and CD45RA-Foxp3^high activated Tfr cells. Furthermore, increased number of PD-1+ICOS+Tfh cells was associated with B cells, while decreased numbers of Tfr and their subsets was strongly associated with aTreg cells in pSS patients. Also, the higher proportion of PD-1+ICOS+Tfh cells was positively correlated with higher level of autoantibodies, ESR, IgG, cytokines (IL-2, IL-4, IL-10, IL-17, IFN-γ, TNF-α, IL-21 and sIL-2αR), and disease activity. Unexpectedly, the elevated PD-1+ICOS+Tfh:CD45RA-Foxp3^high activated Tfr ratio had the greatest ability to discriminate between pSS and HC, and sirolimus therapy restored the PD-1+ICOS+Tfh cells:CD45RA-Foxp3^high activated Tfr ratio, and controlled disease activity.

CONCLUSION

The novel ratio of PD-1+ICOS+Tfh to CD45RA-Foxp3^high activated Tfr cells can effectively discriminate the pSS patients from controls, and Tfr cell subsets may resemble Treg cell lineages. Furthermore, the PD-1+ICOS+Tfh cells can be used as a biomarker of disease activity and to verify the therapeutic effects of sirolimus in pSS.

Association of primary Sjögren’s syndrome with incident heart failure: a secondary analysis of health claims data in Taiwan

Objective:

Mounting evidence has demonstrated that various chronic inflammatory diseases are associated with incident heart failure (HF). However, there is scarce evidence about the association between primary Sjögren’s syndrome (pSS) and HF. We aimed to explore this association using a nationwide database in Taiwan.

Methods:

We selected patients with incident pSS and no history of HF. Using propensity score matching based on age, sex, cohort entry time, comorbidities, and concomitant medications, cohorts of patients with and without pSS (as controls) were created in a 1:1 ratio and the groups were compared. The cumulative incidence of HF was calculated using Kaplan–Meier estimation. Cox proportional hazard regression analysis was used to measure the hazard ratio (HR) of HF-related hospitalization for the pSS cohort compared with the comparison group.

Results:

A total of 16,466 pairs of patients with pSS and those without pSS were identified. The cumulative incidence of HF-related hospitalization at 3, 5, and 10 years in patients with pSS was 1.05%, 1.89%, and 4.33%, respectively. The risk of HF-related hospitalization was not higher in patients with pSS than in the general population (HR: 0.98, 95% confidence interval [CI]: 0.84–1.14). There was no difference in survival probability after the first episode of HF-related hospitalization between pSS and non-pSS groups.

Conclusion:

Our results suggest that distinct inflammatory spectrums in each chronic inflammatory disease might have differential impacts on cardiac function and subsequent risk of HF. Future studies are needed to elucidate the complex and diverse mechanisms of HF in various chronic autoimmune diseases.

Acinar Atrophy, Fibrosis and Fatty Changes Are Significantly More Common than Sjogren’s Syndrome in Minor Salivary Gland Biopsies

Background and Objective: Hyposalivation and xerostomia can result from a variety of conditions. Diagnosis is based on a combination of medical history, clinical and serological parameters, imaging, and minor salivary gland biopsy when indicated. The Objective was to characterize microscopic changes in minor salivary gland biopsies taken in patients with xerostomia. Materials and Methods: 10-year retrospective analysis of minor salivary gland biopsies, 2007–2017. Histomorphometric analysis included gland architecture, fibrosis, fat replacement, inflammation and stains for IgG/IgG4, when relevant. Results: 64 consecutive biopsies, of which 54 had sufficient tissue for diagnosis of Sjogren’s Syndrome (SS) were included (18 males, 46 females, average age 56 (±12.5) years). Only 12 (22.2%) were microscopically consistent with SS, none stained for IgG4. Medical conditions were recorded in 40 (63%), most frequently hypertension and hyperlipidemia (28% each). Medications were used by 45 (70%), of which in 50% more than one. Xerostomia in non-SS cases was supported by abnormal gland morphology, including acinar atrophy, fibrosis and fatty replacement. All morphological abnormalities are correlated with age, while fatty replacement correlated with abnormal lipid metabolism. Multiple medications correlated with microscopic features which did not correspond with SS. Conclusions: SS was confirmed in a minority of cases, while in the majority fatty replacement, fibrosis and multiple medications can explain xerostomia, and are related to aging and medical conditions. Medical history and auxiliary tests could lead to correct diagnosis in non-SS patients, avoiding biopsy. The necessity of a diagnostic biopsy should be given serious consideration only after all other diagnostic modalities have been employed.

Sjogren's Syndrome: Recent Updates

Primary Sjögren's syndrome (SS) is a chronic systemic autoimmune disorder affecting primarily perimenopausal women [...].

A case of digital autoamputation with concurrent Sjogren's syndrome, antiphospholipid syndrome, and ovarian cancer

Sjogren's syndrome (SS) is a chronic autoimmune disease that is characterized by focal lymphocytic infiltration of the exocrine glands. SS mostly affects middle-aged women, and results in an increased risk of developing malignant neoplasm, particularly hematologic malignancies. The concurrent occurrence of SS, ovarian cancer, and autoimmune disease is very rare. Here, we present a case with postoperative digital autoamputation in a young Sjogren's patient diagnosed with high-grade serous ovarian cancer. The patient was later also diagnosed with antiphospholipid syndrome. Clinicians should note that female genital tract malignancies might occur in autoimmune diseases. In addition, when planning for surgery, they should also be aware of the possibility of another autoimmune disease and different patterns of postoperative complications such as venous thromboembolism and thrombophlebitis. A multidisciplinary approach is required to achieve successful management. To the best of the authors' knowledge, this is the second case with concurrent SS and ovarian cancer and the first case with concurrent SS, antiphospholipid syndrome, and ovarian cancer.

The role of albumin-to-globulin ratio in undifferentiated arthritis: Rheumatoid arthritis versus primary Sjögren syndrome

Objectives

This study aims to compare initial albumin-to-globulin ratio (AGR) in patients with rheumatoid arthritis (RA) and primary Sjögren syndrome (pSS) presenting with undifferentiated arthritis (UA) and to investigate whether there was a difference in terms of AGR between the two patient groups and healthy controls.

Patients and methods

Between January 2019 and December 2019, a total of 177 patients including 96 RA (10 males, 86 females; mean age: 53.6±10.8 years; range, 21 to 74 years) and 81 pSS (5 males, 76 females; mean age: 53.2±14.1 years; range, 23 to 79 years) and 82 healthy controls (20 males, 62 females; mean age: 50.5±13.6 years; range, 20 to 79 years) were included in this case-control study. Demographic characteristics, albumin, and globulin levels of all participants were recorded. The AGR, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), anti-nuclear antibody (ANA), and anti-citrullinated protein antibodies (ACPA) were assessed.

Results

The mean AGR was 1.50±0.16 in the control group, 1.48±0.24 in the RA group, and 1.30±0.23 in the pSS group, indicating a significant difference between the pSS and the other two groups (p<0.001). The receiver operating characteristic analysis revealed that the cut-off value for AGR was 1.39 (area under the curve=0.736) with a sensitivity of 0.642 and a specificity of 0.646 (p<0.001). The ESR and CRP values were higher (p<0.001), and ANA (p<0.001) and RF (p=0.003) positivity were lower in the RA group, compared to the pSS group.

Conclusion

This study findings indicate that AGR is a helpful tool in the differential diagnosis of RA and pSS presenting with UA at the time of admission, and Sjögren syndrome should be considered in case of AGR ≤1.39.

Uncovering potential single nucleotide polymorphisms, copy number variations and related signaling pathways in primary Sjogren's syndrome

Primary Sjogren’s syndrome (pSS) is a complex systemic autoimmune disease, which is difficult to accurately diagnose due to symptom diversity in patients, especially at earlier stages. We tried to find potential single nucleotide polymorphisms (SNPs), copy number variations (CNVs) and related signaling pathways. Genomic DNA was extracted from peripheral blood of 12 individuals (7 individuals from 3 pSS pedigrees and 5 sporadic cases) for whole-exome sequencing (WES) analysis. SNPs and CNVs were identified, followed by functional annotation of genes with SNPs and CNVs. Gene expression profile (involving 64 normal controls and 166 cases) was downloaded from the Gene Expression Omnibus database (GEO) dataset for differentially expression analysis. Sanger sequencing and in vitro validation was used to validate the identified SNPs and differentially expressed genes, respectively. A total of 5 SNPs were identified in both pedigrees and sporadic cases, such as FES, PPM1J, and TRAPPC9. A total of 3402 and 19 CNVs were identified in pedigrees and sporadic cases, respectively. Fifty-one differentially expressed genes were associated with immunity, such as BATF3, LAP3, BATF2, PARP9, and IL15RA. AMPK signaling pathway and cell adhesion molecules (CAMs) were the most significantly enriched signaling pathways of identified SNPs. Identified CNVs were associated with systemic lupus erythematosus, mineral absorption, and HTLV-I infection. IL2-STAT5 signaling, interferon-gamma response, and interferon-alpha response were significantly enriched immune related signaling pathways of identified differentially expressed genes. In conclusion, our study found some potential SNPs, CNVs, and related signaling pathways, which could be useful in understanding the pathological mechanism of pSS.

Electrostatic and Covalent Assemblies of Anionic Hydrogel-Coated Gold Nanoshells for Detection of Dry Eye Biomarkers in Human Tears

Although dry eye is highly prevalent, many challenges exist in diagnosing the symptom and related diseases. For this reason, anionic hydrogel-coated gold nanoshells (AuNSs) were used in the development of a label-free biosensor for detection of high isoelectric point tear biomarkers associated with dry eye. A custom, aldehyde-functionalized oligo(ethylene glycol)acrylate (Al-OEGA) was included in the hydrogel coating to enhance protein recognition through the formation of dynamic covalent (DC) imine bonds with solvent-accessible lysine residues present on the surface of select tear proteins. Our results demonstrated that hydrogel-coated AuNSs, composed of monomers that form ionic and DC bonds with select tear proteins, greatly enhance protein recognition due to changes in the maximum localized surface plasmon resonance wavelength exhibited by AuNSs in noncompetitive and competitive environments. Validation of the developed biosensor in commercially available pooled human tears revealed the potential for clinical translation to establish a method for dry eye diagnosis.

Proteomic profiling of saliva reveals association of complement system with primary Sjögren's syndrome

INTRODUCTION

To compare the saliva proteomes of experimental Sjögren's syndrome (ESS) model mice and healthy controls to identify potential diagnostic biomarkers for primary Sjögren's syndrome (pSS).

METHODS

Proteins were extracted from the saliva of three ESS and three normal control mice using the data-independent acquisition technique. R language was used to identify the differentially expressed proteins (DEPs). Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed to functionally annotate the DEPs. The protein-protein interaction (PPI) network was constructed and the core proteins were identified with the STRING website and Cytoscape software. The concentrations of Serpin family G member 1 (SERPING1), C3, complement factor H (CFH), fibrinogen alpha (FGA), and fibrinogen gamma (FGG) in saliva were determined by ELISA.

RESULTS

A total of 1722 DEPs were identified in the saliva of the ESS mice relative to the controls, of which 50 showed significantly different expression levels between the two groups. SERPING1, C3, CFH, FGA, and FGG were significantly downregulated, and keratin 4 (Krt4) and transglutaminase 3 (TGM3) were upregulated in the saliva of ESS mice. The PPI network showed that SERPING1, C3, FGG, FGA, TGM3, and hemopexin (HPX) were the core proteins. ELISA results showed that the expression of C3, CFH, FGA, and SERPING1 were significantly downregulated in the saliva of ESS mice. However, the expression of FGG was a little downregulated but with no significant difference. SERPING1, FGG, and FGA may downregulate the complement C3 by inhibiting immune complement system, thereby promoting pSS progression.

CONCLUSIONS

The salivary proteome of ESS mice was markedly different from that of healthy controls, suggesting that salivary proteomics is a promising noninvasive diagnostic tool for pSS. SERPING1, C3, CFH, FGA, and FGG are potential biomarkers of pSS.

+3179G/A Insulin-Like Growth Factor-1 Receptor Polymorphism: A Novel Susceptibility Contributor in Anti-Ro/SSA Positive Patients with Sjögren's Syndrome: Potential Clinical and Pathogenetic Implications

Background: Alterations of the insulin-like growth factor (IGF) pathway along with genetic variations of the IGF1 receptor (IGF1R) gene have been linked to the development of systemic autoimmunity, possibly through apoptosis induction. This study aims to investigate whether genetic variations of the IGF1R contribute to Sjögren’s syndrome (SS) pathogenesis and explores potential functional implications. Methods: DNA extracted from whole peripheral blood derived from 277 primary SS patients, complicated or not by lymphoma, and 337 Healthy controls (HC) was genotyped for the rs2229765 IGF1R polymorphism using the RFLP-PCR assay. Gene expression of IGF1R and IGF1 isoforms, caspases 1, 4, and 5, and inflammasome components NLRP3, ASC, IL1β, IL18, IL33, IGFBP3, and IGFBP6 were quantitated by RT-PCR in total RNA extracted from minor salivary gland biopsies (MSGs) of 50 SS patients and 13 sicca controls (SCs). In addition, IGF1R immunohistochemical (IHC) expression was assessed in formalin-fixed, paraffin-embedded MSG tissue sections derived from 10 SS patients and 5 SCs. Results: The prevalence of the A/A genotype of the rs2229765 IGF1R polymorphism was significantly higher in the anti-Ro/SSA positive SS population compared to healthy controls (24.8% vs. 10.7%, p = 0.001). Moreover, IGF1Rs at both mRNA and protein levels were reduced in SS-derived MSGs compared to SCs and were negatively associated with caspase 1 transcripts. The latter were positively correlated with NLRP3, ASC, and IL1β at the salivary gland tissue level. IGF1R expression in peripheral blood was negatively correlated with ESR and IgG serum levels and positively correlated with urine-specific gravity values. Conclusions: The rs2229765 IGF1R variant confers increased susceptibility for seropositive primary SS. Dampened IGF1R mRNA and protein expression in salivary gland tissues could be related to increased apoptosis and subsequently to the activation of inflammasome pathways.

Gold Nanoparticles: Multifaceted Roles in the Management of Autoimmune Disorders

Gold nanoparticles (GNPs) have been recently applied for various diagnostic and therapeutic purposes. The unique properties of these nanoparticles (NPs), such as relative ease of synthesis in various sizes, shapes and charges, stability, high drug-loading capacity and relative availability for modification accompanied by non-cytotoxicity and biocompatibility, make them an ideal field of research in bio-nanotechnology. Moreover, their potential to alleviate various inflammatory factors, nitrite species, and reactive oxygen production and the capacity to deliver therapeutic agents has attracted attention for further studies in inflammatory and autoimmune disorders. Furthermore, the characteristics of GNPs and surface modification can modulate their toxicity, biodistribution, biocompatibility, and effects. This review discusses in vitro and in vivo effects of GNPs and their functionalized forms in managing various autoimmune disorders (Ads) such as rheumatoid arthritis, type 1 diabetes, and multiple sclerosis.

Type I interferon detection in autoimmune diseases: challenges and clinical applications

INTRODUCTION

Accumulating data highlights that the dysregulation of type I interferon (IFN) pathways plays a central role in the pathogenesis of several systemic and organ-specific autoimmune diseases. Advances in understanding the role of type I IFNs in these disorders can lead to targeted drug development as well as establishing potential disease biomarkers.

AREAS COVERED

Here, we summarize current knowledge regarding the role of type I IFNs in the major systemic, as well as organ-specific, autoimmune disorders, including prominent inflammatory CNS disorders like multiple sclerosis.

EXPERT OPINION

Type I IFN involvement and its clinical associations in a wide spectrum of autoimmune diseases represents a promising area for research aiming to unveil common pathogenetic pathways in systemic and organ-specific autoimmunity.

Handheld spatial frequency domain imager for noninvasive Sjögren's syndrome labial salivary gland biopsy

A labial salivary gland biopsy (LSGB) plays an essential role in diagnosing Sjögren's syndrome (SS), but its clinical application is limited due to its invasiveness. Here, we present a handheld single snapshot multiple-frequency demodulation-spatial frequency domain imaging (SSMD-SFDI) device for a rapid optical biopsy of labial salivary glands noninvasively. The structural and physiological parameters of lower lip mucosa were obtained from the light reflectance of the layered oral mucosa. The recovered parameters were found to correlate strongly with the progression of SS. In our pilot study on 15 healthy subjects and 183 SS patients, a support vector machine (SVM) classifier using the measured parameters distinguished healthy subjects, LSGB I, II, III, and IV patients in sequence with AUCs of 0.979, 0.898, 0.906, and 0.978, respectively. Critical structural and physiological alterations in the mucosa due to SS were further identified and used to assess its risk using an explainable neural network. The handheld spatial frequency domain imager may serve as a valuable label-free and noninvasive tool for early diagnosing and surveying SS.

Interferon (IFN)-stimulated gene 15: A novel biomarker for lymphoma development in Sjögren's syndrome

OBJECTIVE

We investigated whether interferon (IFN) induced genes could serve as biomarkers for the detection of lymphoma development among patients with Sjögren's syndrome (SS).

METHODS

Total RNA was extracted from 98 labial minor salivary glands (LMSG) biopsies of SS patients [61 not complicated by lymphoma (SS-nL) and 37 complicated by Non-Hodgkin Lymphoma (NHL) (SS-L)] and 67 matched peripheral blood (PB) samples, as well as from 30 LMSG biopsies and 17 matched PB derived from sicca controls (SC). RNA sequencing was performed in LMSG biopsies of high and low risk SS patients for lymphoma development and SC. Expression analysis of type I (MX-1, IFIT-1, IFI44 and ISG-15) and type II IFN induced (CXCL9/MIG-1, GBP-1) genes was performed by real time PCR.

RESULTS

ISG-15 transcript levels were significantly higher in SS-L patients compared to SS-nL patients in both LMSG tissues and PB specimens. Additionally, MIG-1 was found to display higher expression values in LMSG tissues, but not in PB derived from SS-L patients compared to the SS-nL group. A coordinate expression in PB/LMSG of type I IFN (ISG-15, MX-1 and IFI44), but not type II IFN induced genes was also observed.

CONCLUSION

ISG-15 gene expression was able to distinguish SS-nL and SS-L at both periphery and tissue level and therefore could represent a novel biomarker for lymphoma development among SS patients. PB and LSMG seem to share a common transcriptional profile of type I IFN pathway.

Role of ranulas in early diagnosis of Sjögren’s syndrome: A case report

BACKGROUND

Although the presentations of Sjögren’s syndrome (SS) are variable, ranging from mild dryness to wider systemic involvement, ranulas as early clinical signs were scarcely reported. Here, we present an adult patient with SS, who developed a unilateral simple ranula and was diagnosed primary SS 3 years later. We also provide a review of cases of SS and ranulas from 1980 to 2020.

CASE SUMMARY

A 22-year-old girl was found to have a left painless floor-of-mouth lesion 3 years ago, without obvious trauma or inducement. The diagnosis of a unilateral (left) simple ranula was made, and the ranula was surgically treated. Within 3 years after the ranula surgery, she developed acute lymphadenectasis in unilateral parotid twice without inducement, and ultrasonic examination revealed diffuse lesions in bilateral parotids and submandibular glands, which strongly suggested SS. Serologic tests and the unstimulated whole saliva flow rate confirmed the SS diagnosis.

CONCLUSION

Our study underlines that ranulas are early clinical signs of SS. As early diagnosis and early intervention of SS are important to obtain better outcomes, our findings underline the need for histopathological test after sublingual adenectomy and imaging detection of exocrine glands for the patients with ranulas.

A Primary Parotid Mucosa-Associated Lymphoid Tissue Non-Hodgkin Lymphoma in a Patient With Sjogren Syndrome

The salivary gland tumors are rare entities and the majority of these are benign. However, there are some entities such as prior neck radiation, certain infections, and systemic diseases which should raise the clinical suspicion for a malignant lesion. Patients with Sjogren syndrome are at increased risk for a salivary gland neoplasm, specifically non-Hodgkin lymphoma. While clinical findings play an important role in the initial workup, imaging plays a critical role in the diagnosis and management. This case describes a patient with Sjogren syndrome who presented with a left face mass where imaging was able to confidently diagnose her with a suspicious parotid neoplasm with lymphoma as the favored diagnosis. After histological evaluation, she was diagnosed with primary parotid mucosa-associated lymphoid tissue (MALT) non-Hodgkin lymphoma after which she went on to non-operative management.

A 77-Year-Old Woman With Sjogren Syndrome Experiencing Progressive Dyspnea on Exertion and Nonproductive Cough

CASE PRESENTATION

A 77-year-old woman was referred to our interstitial lung disease unit. She presented with a history of progressive dyspnea on exertion and nonproductive, persistent cough over the previous year. She was diagnosed with Sjogren syndrome two years ago by a rheumatologist. In the context of Sjogren syndrome, she reported chronic xerostomia and xerophthalmia for the last 5 years. Her history was also notable for the presence of arterial hypertension and hypothyroidism. She denied the presence of shortness of breath, chest pain, arthralgia, muscle weakness, weight loss, night sweats, and fatigue. She reported exposure to house mold. There was no family history of respiratory diseases. The patient never smoked and denied alcohol consumption, illicit drug use, or any occupational exposures.

Autoimmune B Cell Repertoire in a Mouse Model of Sjögren's Syndrome

In genetically prone individuals, chronic immune activation may lead to expansion of autoreactive lymphocyte clones that can induce organ damage developing autoimmune disorders. Sjögren’s Syndrome (SjS) is a systemic chronic autoimmune disease that primarily affects exocrine glands. Despite the accumulated evidences of profound B-cell alterations of humoral immunity, the repertoire and development of B-cell autoreactivity in SjS remains to be determined. We hypothesize that SjS mice will have an increased frequency of self-reactive B cells with a progressive evolution to antigen-driven oligoclonality. Here, we study the B cell repertoire of NOD.H-2^h4 mice, a mouse model of spontaneous autoimmunity mimicking SjS without developing diabetes. A library of 168 hybridomas from NOD.H-2^h4 mice and 186 C57BL/6J splenocytes at different ages was created. The presence of mono or polyreactive autoantibodies to several antigens was evaluated by ELISA, and their staining patterns and cellular reactivity were tested by IFA and FACS. We observed a higher frequency of autoreactivity among B-cell clones from NOD.H-2^h4 mice as compared to wild-type mice. The presence of polyreactive and autoreactive IgG clones increased with mice age. Strikingly, all anti-Ro52 autoantibodies were polyreactive. No loss of polyreactivity was observed upon antibody class switching to IgG. There was a progression to oligoclonality in IgG B cells with mice aging. Our results indicate that in the NOD.H-2^h4 mouse model of SjS, IgG+ B cells are mainly polyreactive and might expand following an unknown antigen-driven positive selection process.

Musculoskeletal Manifestations in Sjogren's Syndrome: An Orthopedic Point of View

Sjogren's syndrome (SS) is a frequent entity with a broad symptomatology spectrum, mainly affecting the salivary and lachrymal glands. The disease also affects the musculoskeletal system targeting bones, specific joints, muscles, and the peripheral nerve system. Disease related clinical manifestations canhave an accumulative impact, as the syndrome is commonly associated with other rheumatic diseases. A literature review was performed with the aim to assess the in-depth association of Sjogren's syndrome and its treatment agents with the musculoskeletal system and further investigate its potential relevance with common orthopedic postoperative complications.

Activation of Toll-Like Receptor 7 Signaling Pathway in Primary Sjögren's Syndrome-Associated Thrombocytopenia

Objectives: To identify the importance of the Toll-like receptor (TLR) pathway using B cell high-throughput sequencing and to explore the participation of the TLR7 signaling pathway in primary Sjogren's syndrome (pSS)-associated thrombocytopenia in patient and mouse models.

Methods: High-throughput gene sequencing and bioinformatic analyses were performed for 9 patients: 3 patients with pSS and normal platelet counts, 3 patients with pSS-associated thrombocytopenia, and 3 healthy controls. Twenty-four patients with pSS were recruited for validation. Twenty-four non-obese diabetic (NOD) mice were divided into the TLR7 pathway inhibition (CA-4948), activation (Resiquimod), and control groups. Serum, peripheral blood, bone marrow, and submandibular glands were collected for thrombocytopenia and TLR7 pathway analysis.

Results: Seven hub genes enriched in the TLR pathway were identified. Compared to that in control patients, the expression of interleukin (IL)-8 and TLR7 pathway molecules in B-cells was higher in patients with pSS-associated thrombocytopenia. Platelet counts exhibited a negative correlation with serum IL-1β and IL-8 levels. In NOD mice, CA-4948/Resiquimod treatment induced the downregulation/upregulation of the TLR7 pathway, leading to consistent elevation/reduction of platelet counts. Megakaryocyte counts in the bone marrow showed an increasing trend in the Resiquimod group, with more naked nuclei. The levels of IL-1β and IL-8 in the serum and submandibular gland tissue increased in the Resiquimod group compared with that in CA-4948 and control groups.

Conclusion: pSS-associated thrombocytopenia may be a subset of the systemic inflammatory state as the TLR7 signaling pathway was upregulated in B cells of patients with pSS-associated thrombocytopenia, and activation of the TLR7 pathway led to a thrombocytopenia phenotype in NOD mice.

Leukocyte Immunoglobulin-Like Receptor A3 (LILRA3): A Novel Marker for Lymphoma Development among Patients with Young Onset Sjogren's Syndrome

Background: Primary Sjogren’s syndrome (SS) is an autoimmune disease with a strong predilection for lymphoma development, with earlier disease onset being postulated as an independent risk factor for this complication. Variations of the Leukocyte immunoglobulin-like receptor A3(LILRA3) gene have been previously shown to increase susceptibility for both SS and non-Hodgkin B-cell lymphoma (B-NHL) in the general population. We aimed to investigate whether variations of the LILRA3 gene could predispose for lymphoma development in the context of SS. Methods: Study population, all of Greek origin, included 101 SS cases with a current or previous diagnosis of lymphoma (SS-lymphoma, SS-L) and 301 primary SS patients not complicated by lymphoma (SS-non-lymphoma, SS-nL). All SS patients fulfilled the 2016 SS American College of Rheumatology/European league against Rheumatism (ACR/EULAR) classification criteria. A total of 381 healthy controls (HC) of similar age/sex/race distribution were also included. On the basis of the age of SS onset and the presence or absence of adverse predictors for lymphoma development, SS patients were further stratified into younger (≤40 years) and older (>40 years) age of disease onset, as well as into high/medium and low risk groups. Polymerase chain reaction (PCR) was implemented for the detection of the following LILRA3 gene variants: homozygous non-deleted or functional wild type (+/+) heterozygous (+/−) and homozygous deleted (−/−). LILRA3 serum protein levels were quantitated by enzyme-linked immunosorbent assay (ELISA) in 85 individuals (29 SS-L, 35 SS-nL patients and 21 HC). Results: While no statistically significant differences were detected in the overall frequency of LILRA3 gene variants between SS-L, SS-nL and HC groups, LILRA3 serum protein levels were increased in the SS-L group compared to HC (1.27 ± 1.34 vs. 0.38 ± 0.34 ng/mL, p-value: 0.004). After stratification according to the age of SS onset and history of lymphoma, as well as the presence or absence of adverse predictors for lymphoma development, the prevalence of the functional LILRA3 gene variant was found to be significantly increased in the young onset SS-L group compared to the HC of similar age and sex distribution (100% vs. 82.9%, p = 0.03), as well as in the high/medium risk SS compared to the low risk SS (91.3 vs. 78.3%, p = 0.0012). Of note, young onset SS-L and SS-nL groups displayed higher LILRA3 serum levels compared to their older counterparts (p-values: 0.007 and 0.0005, respectively). Conclusion: The functional LILRA3 gene variant increases susceptibility to SS-related lymphoma development in patients with a disease onset of <40 years old, implying that genetically determined deranged immune responses in younger SS individuals could underly their pronounced risk for lymphoma development.