Clinical features and risk factors of primary Sjögren's syndrome complicated with severe pneumonia: a case-control study

OBJECTIVES

To analyze clinical characteristics, risk factors, pathogen distribution, and prognostic markers in primary Sjögren's syndrome (pSS) patients with severe pneumonia (SP) compared to those without severe pneumonia (NSP).

METHODS

This case-control study included 24 hospitalized pSS patients with SP and 96 NSP at the first affiliated hospital of Soochow university from June 2014 to May 2023. Data encompassing demographics, comorbidities, treatments, and laboratory results were retrospectively collected. Univariate and multivariate regression analyses, ROC curves, and statistical analyses using SPSS 23.0 assessed risk factors. The study retrospectively analyzed clinical features and risk factors, highlighting distinct parameters between pSS patients with and without SP.

RESULTS

Marked differences were observed in several parameters: pSS activity(P < 0.001), white blood cell (P = 0.043), lymphocyte (P < 0.001), neutrophils (P = 0.042), C-reactive protein (P = 0.042), and CD8+ T cell (P = 0.017). Notably, lymphocyte count and SS activity demonstrated robust discrimination ability (AUC > 0.85). C-reactive protein (CRP), procalcitonin, CD4+ T cell, and IgA showed significant associations with SP; higher CRP levels correlated with increased risk, while lower CD4+ T cell and IgA levels associated with increased risk. SS activity significantly impacted outcomes. Various biomarkers exhibited diverse discriminatory abilities but lacked strong predictive associations with outcomes.

CONCLUSION

pSS patients with SP exhibited higher disease activity and altered immune profiles compared to those NSP. Lymphocyte count and SS activity emerged as robust discriminators. Higher CRP levels correlated with increased risk of SP, while lower CD4+T cell and IgA levels associated with increased risk. SS activity significantly impacted patient outcomes. Key Points • pSS patients with SP exhibited higher disease activity and altered immune profiles compared to those NSP. • Lymphocyte count and SS activity emerged as robust discriminators. • Higher CRP levels correlated with increased risk of SP, while lower CD4+ T cell and IgA levels associated with decreased risk. • SS activity significantly impacted patient outcomes.

Development of a nomogram for membranous nephropathy prediction in patients with primary Sjögren's syndrome: a 6-year retrospective study

Objectives

Nephritis is a life-threatening complication of primary Sjögren's syndrome (pSS), with membranous nephropathy (MN) being prevalent. Renal biopsy is the gold standard for MN diagnosis, but it is invasive and cannot be repeatedly performed. This study aimed to develop a nomogram for the prediction of MN in patients with pSS.

Methods

This retrospective study included patients with pSS admitted to the Rheumatology and Immunology Department of the First Affiliated Hospital of China Medical University between January 2015 and January 2021. A nomogram was developed using multivariable logistic regression analysis and evaluated using receiver operating characteristic (ROC) curve analysis. Bootstrap resampling analysis (1,000 times) was performed to evaluate the nomogram for discrimination and the calibration curve for consistency.

Results

A total of 237 patients with pSS [aged 53.00 (44.00, 61.00) years] were included, with 35 pSS-MN patients. Based on clinical practice and multivariable logistic regression analysis, seven variables associated with pSS-MN were selected, including white blood cells, creatine, complement 3, rheumatoid factor, antinuclear antibodies, anti-SSA antibody, and interstitial lung disease. The area under the ROC curve was 0.860 (95% confidence interval: 0.796-0.919), indicating good predictive power. In addition, the nomogram exhibited excellent performance, as demonstrated by the calibration curve and decision curve analysis.

Conclusion

This study developed a risk prediction nomogram for MN in patients with pSS, with high predictive power. It may be used to improve the management of patients with pSS.

Molecular mechanisms of saliva secretion and hyposecretion

The exocrine salivary gland secretes saliva, a fundamental body component to maintain oral homeostasis. Saliva is composed of water, ions, and proteins such as amylase, mucins, and immunoglobulins that play essential roles in the digestion of food, lubrication, and prevention of dental caries and periodontitis. An increasing number of people experience saliva hyposecretion due to aging, medications, Sjögren's syndrome, and radiation therapy for head and neck cancer. However, current treatments are mostly limited to temporary symptomatic relief. This review explores the molecular mechanisms underlying saliva secretion and hyposecretion to provide insight into putative therapeutic targets for treatment. Proteins implicated in saliva secretion pathways, including Ca2+ -signaling proteins, aquaporins, soluble N-ethylmaleimide-sensitive factor attachment protein receptors, and tight junctions, are aberrantly expressed and localized in patients with saliva hyposecretion, such as Sjögren's syndrome. Analysis of studies on the mechanisms of saliva secretion and hyposecretion suggests that crosstalk between fluid and protein secretory pathways via Ca2+ /protein kinase C and cAMP/protein kinase A regulates saliva secretion. Impaired crosstalk between the two secretory pathways may contribute to saliva hyposecretion. Future research into the detailed regulatory mechanisms of saliva secretion and hyposecretion may provide information to define novel targets and generate therapeutic strategies for saliva hyposecretion.

The universal effects of low-dose interleukin-2 across 13 autoimmune diseases in a basket clinical trial

BACKGROUND

A Tregs insufficiency is central to autoimmune and inflammatory diseases pathophysiology and low dose interleukin-2 (IL-2LD) can specifically activate Tregs.

OBJECTIVE

To assess IL-2LD therapeutic potential and select diseases for further clinical development, we performed an open-label, phase 2a, disease-finding, "basket trial" involving patients with one of 13 different autoimmune diseases.

METHODS

81 patients treated with IL-2LD (1 million IU/day) for 5 days, followed by fortnightly injections. The first 48 patients received diluted Proleukin®, while the subsequent 33 received ready-to-use ILT-101®. The primary endpoint was the change in Tregs at day-8 compared to baseline. Key secondary endpoints included clinical efficacy assessments using the Clinical Global Impression (CGI) scale, disease-specific scores, and EuroQL-5D-5L.

RESULTS

Our study unveiled a universal and significant expansion and activation of Tregs, without concomitant Teffs activation, across all 13 autoimmune diseases. Both Proleukin® and ready-to-use ILT-101® demonstrated identical effects on Tregs. CGI scores reflecting activity, severity, and efficacy were significantly reduced in the overall patient population. Disease-specific clinical scores improved in five of the six disease cohorts with at least six patients, namely ankylosing spondylitis, systemic lupus erythematosus, Behçet's disease, Sjögren's syndrome, and systemic sclerosis. Urticaria was the only severe adverse event related to treatment.

CONCLUSION

IL-2LD was well-tolerated, exhibiting specific Treg activation and clinical improvements across the 13 autoimmune diseases.

CLINICAL IMPLICATION

Tregs stimulation by IL-2LD is a promising therapeutic strategy and IL-2LD holds considerable promise for integration into combinatorial therapeutic approaches.

CD4 T cell-secreted IFN-γ in Sjögren's syndrome induces salivary gland epithelial cell ferroptosis

BACKGROUND

Sjögren's syndrome (SS) is a chronic autoimmune disease that predominantly affects exocrine glands. Previous studies have demonstrated that upregulated interferon-gamma (IFN-γ) in SS triggers ferroptosis in salivary gland epithelial cells (SGECs), resulting in impaired salivary gland secretion. However, the immune cells responsible for secreting IFN-γ remain unclear. Therefore, this study conducted bioinformatics analysis and molecular validation to identify the origin of IFN-γ in SS salivary gland.

METHODS

The 'limma' package in R software was utilized to identify differentially expressed genes (DEGs) in the human SS dataset. Subsequently, the identified DEGs were compared with the ferroptosis database and screened through Cytoscape to determine candidate genes. The cellular localization and expression patterns of candidate genes were further confirmed in the salivary gland single-cell RNA sequence (scRNA-seq) data set from healthy control and SS mice. Furthermore, in vitro and in vivo studies were performed to analyze the effect of CD4 T-secreted IFN-γ on SGECs' ferroptosis and functions.

RESULTS

Upregulated TLR4, IFNG, and IL33 were screened as candidates ferroptosis ferroptosis-inducing genes in SS salivary glands. The association of IFNG and IL33 with CD4 T cells was established through immune infiltration analysis. The expression of IFN-γ on CD4 T cells was robustly higher compared with that of IL33 as evidenced by scRNA-seq and immunofluorescence co-localization. Subsequent experiments conducted on candidate genes consistently demonstrated the potent ability of IFN-γ to induce SGECs' ferroptosis and inhibit AQP5 expression.

CONCLUSIONS

Our findings indicate that CD4 T cell-secreted IFN-γ in SS induces SGECs' ferroptosis and inhibits AQP5 expression.

Identification of outcome domains in primary Sjögren's disease: A scoping review by the OMERACT Sjögren disease working group

OBJECTIVES

Sjögren's disease (SjD) is a heterogenous disease with a wide range of manifestations, ranging from symptoms of dryness, fatigue, and pain, to systemic involvement. Considerable advances have been made to evaluate systemic activity or patient-reported outcomes, but most of the instruments were not able to assess all domains of this multifaceted disease. The aim of this scoping review was to generate domains that have been assessed in randomized controlled trials, as the first phase of the Outcome Measures in Rheumatology (OMERACT) process of core domain set development.

METHODS

We systematically searched Medline (Pubmed) and EMBASE between 2002 and March 2023 to identify all randomized controlled trials assessing relevant domains, using both a manual approach and an artificial intelligence software (BIBOT) that applies natural language processing to automatically identify relevant abstracts. Domains were mapped to core areas, as suggested by the OMERACT 2.1 Filter.

RESULTS

Among the 5,420 references, we included 60 randomized controlled trials, focusing either on overall disease manifestations (53%) or on a single organ/symptom: dry eyes (17%), xerostomia (15%), fatigue (12%), or pulmonary function (3%). The most frequently assessed domains were perceived dryness (52% for overall dryness), fatigue (57%), pain (52%), systemic disease activity (45%), lacrimal gland function (47%) and salivary function (55%), B-cell activation (60%), and health-related quality of life (40%).

CONCLUSION

Our scoping review highlighted the heterogeneity of SjD, in the study designs and domains. This will inform the OMERACT SjD working group to select the most appropriate core domains to be used in SjD clinical trials and to guide the future agenda for outcome measure research in SjD.

Rheumatic diseases in migrant patients resident in Tuscany: epidemiological data analysis and single-center experience

OBJECTIVE

In the last decades, the number of foreigners in Tuscany has considerably increased with a multiethnic distribution. We reviewed the main rheumatic diseases in the foreign population resident in Tuscany and also reported the experience at the Rheumatology Division of the University Hospital of Careggi, Florence, in order to identify the areas of origin of these patients and the main rheumatic diseases observed in them.

METHODS

The collaboration with the Tuscan Region provided data about foreign patients residing in Tuscany on January 1, 2021 (country of origin, chronic diseases). Moreover, we conducted a retrospective review of the clinical charts of our Rheumatologic Division from January 1, 2019, to December 31, 2020.

RESULTS

In Tuscany, on January 1, 2021, there were 61,373 patients with chronic inflammatory rheumatic diseases, and 3994 of them (6.51%) were foreigners. Most patients were born in Europe (39.03%), followed by the Balkans (15%), South America (11.27%), and North Africa (10.31%). Inflammatory joint diseases, Sjögren syndrome, and systemic lupus erythematosus were the most frequent diseases. In the period 2019-2020, 511 foreign patients visited our Rheumatology Division and mainly originated from the Balkans (34.64%), South America (18%), and European countries (16.44%). In these patients, chronic inflammatory joint diseases and connective tissue diseases (systemic sclerosis, Sjögren syndrome, and systemic lupus erythematosus) were the most prevalent diseases.

CONCLUSIONS

This study provides a picture of the rheumatic diseases affecting foreign patients residing in Tuscany that are in agreement with the epidemiological data previously provided.

Association of serum bisphenols, parabens, and triclosan concentrations with Sjögren Syndrome in the Hangzhou, China population

Exposure to endocrine-disrupting chemicals (EDCs) has been linked to various immune deficiency disorders, including autoimmune diseases like Sjögren Syndrome (SjS). However, the detrimental effects of exposure to EDCs, including bisphenols, parabens, and triclosan (TCS), on SjS have been inadequately documented. Thus, we conducted a cross-sectional study that included both healthy individuals (controls) and patients with SjS (cases). We assessed serum concentrations of bisphenol A (BPA), bisphenol S (BPS), methyl parabens (MeP), ethyl parabens (EtP), and TCS. The relationship between the five EDCs levels and the risk of SjS was also explored. Additionally, we conducted an in-depth analysis of the collective influence of these EDCs mixtures on SjS, employing a weighted quantile sum regression model. Out of the five EDCs analyzed, EtP displayed the highest mean concentration (2.80 ng/mL), followed by BPA (2.66 ng/mL) and MeP (1.99 ng/mL), with TCS registering the lowest level (0.36 ng/mL). Notably, BPS exposure was significantly positively associated with the risk of being diagnosed with SjS (with an odds ratio [OR] of 1.17, p = 0.042). No statistically significant associations with SjS were observed for BPA, MeP, EtP, and TCS (p > 0.05). And we did not observe any significant effects of the EDCs mixture on SjS. To the best of our knowledge, this study is the first to suggest that BPS may potentially increase the risk of SjS. Although no significant effects were observed between other EDCs and SjS risk, we cannot disregard the potential harm of EDCs due to their non-monotonic dose response.

Hyperactivation and altered selection of B cells in patients with paediatric Sjogren's syndrome

OBJECTIVES

Paediatric Sjögren's syndrome (pSS) is a rare chronic autoimmune disorder, characterised by inflammation of exocrine glands. B cell hyperactivation plays a central role in adult-onset Sjogren. This study was designed to analyse B cell and T cell phenotype, levels of BAFF, and selection of autoreactive B cells in patients with pSS.

METHODS

A total of 17 patients diagnosed with pSS and 13 healthy donors (controls) comparable for age were enrolled in the study. B cell and T cell subsets and frequency of autoreactive B cells in peripheral blood were analysed by flow cytometry. Levels of BAFF were analysed by ELISA.

RESULTS

The relative frequency of total B cells, transitional, naïve and switched memory B cells was similar between pSS patients and controls. In patients with pSS, we observed a reduction in the frequency of unswitched memory B cells, an increased frequency of atypical memory B cells and an expansion of PD1hi CXCR5- T peripheral helper cells. Levels of BAFF were higher in patients with pSS compared with controls and correlated with serum levels of total IgG and titres of anti-Ro antibodies. The frequency of autoreactive B cells in the transitional, unswitched memory and plasmablast compartment was significantly higher in pSS patients than in controls.

CONCLUSIONS

Our results point to a hyperactivation of B cells in pSS. Current therapies do not seem to affect B cell abnormalities, suggesting that novel therapies targeting specifically B cell hyperactivation need to be implemented for paediatric patients.

Functional significance of DNA methylation: epigenetic insights into Sjögren's syndrome

Sjögren's syndrome (SjS) is a systemic, highly diverse, and chronic autoimmune disease with a significant global prevalence. It is a complex condition that requires careful management and monitoring. Recent research indicates that epigenetic mechanisms contribute to the pathophysiology of SjS by modulating gene expression and genome stability. DNA methylation, a form of epigenetic modification, is the fundamental mechanism that modifies the expression of various genes by modifying the transcriptional availability of regulatory regions within the genome. In general, adding a methyl group to DNA is linked with the inhibition of genes because it changes the chromatin structure. DNA methylation changes the fate of multiple immune cells, such as it leads to the transition of naïve lymphocytes to effector lymphocytes. A lack of central epigenetic enzymes frequently results in abnormal immune activation. Alterations in epigenetic modifications within immune cells or salivary gland epithelial cells are frequently detected during the pathogenesis of SjS, representing a robust association with autoimmune responses. The analysis of genome methylation is a beneficial tool for establishing connections between epigenetic changes within different cell types and their association with SjS. In various studies related to SjS, most differentially methylated regions are in the human leukocyte antigen (HLA) locus. Notably, the demethylation of various sites in the genome is often observed in SjS patients. The most strongly linked differentially methylated regions in SjS patients are found within genes regulated by type I interferon. This demethylation process is partly related to B-cell infiltration and disease progression. In addition, DNA demethylation of the runt-related transcription factor (RUNX1) gene, lymphotoxin-α (LTA), and myxovirus resistance protein A (MxA) is associated with SjS. It may assist the early diagnosis of SjS by serving as a potential biomarker. Therefore, this review offers a detailed insight into the function of DNA methylation in SjS and helps researchers to identify potential biomarkers in diagnosis, prognosis, and therapeutic targets.

Elevated expression of Toll-like receptor 7 and its correlation with clinical features in patients with primary Sjögren's syndrome

BACKGROUND

The labial salivary glands (LSGs) are important for the diagnosis, evaluation of therapeutic efficacy, and genetic analyses of primary Sjögren's syndrome (pSS). In autoimmune diseases, the recognition of self nucleic acids and viral RNA and DNA through endogenous Toll-like receptor(TLR) triggers the production of type I IFN and pro-inflammatory cytokines, leading to the occurrence and progression of the disease. Here, we detected the expression of TLR7 in LSGs and analyse its correlation with clinical features and serum cytokines in pSS patients.

METHODS

LSGs and serum samples were obtained from 56 pSS patients and 19 non-SS patients (non-pSS patients). The expression of TLR7 in the LSGs was evaluated with immunohistochemistry. The serum levels of interferon-α (IFN-α) and interleukin-6 (IL-6) were quantified by ELISA. Laboratory parameters were measured by clinical standard laboratory techniques.

RESULTS

TLR7-positive cells in pSS were localized in the ductal epithelial cells and lymphocytes of LSGs. The expression of TLR7 was upregulated in pSS patients compared with controls. Patients with anti-Ro52 antibody positivity showed higher TLR7 levels than those who were negative but not those with anti-Ro60 and anti-SSB. TLR7 levels were positively associated with the levels of IgG, IgA, ANA, IL-6, IFN-α and serum globulin but were not associated with IgM, C3, C4, or rheumatoid factor (RF) in serum.

CONCLUSION

TLR7 may be involved in the inflammatory response and the production of antibodies in pSS and plays an important role in local and systemic pSS manifestations. This research showed that TLR7 is involved in pSS pathogenesis.

Salivary Glands and Viral Pathogenesis

The oral cavity is an epidemiologically relevant route of viral transmission due to the shedding of viruses in saliva. With advancements in salivary diagnostics, an increasing number of viruses have been detected. However, the anatomic source of virus in saliva is still largely unknown. Some viruses have a well-established tropism for the salivary glands (SGs), and recent studies have emphasized the importance of the glands as potential reservoirs for infectious viruses. Viral infections of the SGs have been linked to acute and chronic SG pathology and may be associated with SG dysfunction, with phenotypes similar to those seen in SjÖgren's disease (SjD), an autoimmune condition that affects the salivary and lacrimal glands. Understanding the breadth of viruses that infect the SG and the conserved or distinct host responses to these infections may provide insights into the pathogenesis of virus-mediated SG diseases. There is a need for further research to fully understand the molecular mechanisms by which viruses enter and replicate in the glands, their physiologic impact on SG function, and whether the SGs can serve as a long-term reservoir for infectious viral particles. The purpose of this review is to highlight a group of viruses that infect the salivary gland: hepatitis C virus, hepatitis D virus, severe acute respiratory syndrome coronavirus 2, enteric viruses, human T-cell leukemia virus type I, human immunodeficiency virus, human cytomegalovirus, and BK polyomavirus. We focus on the effects of viral infection on salivary gland (SG) inflammation, function, and its association with SjD.

Type 1 interferons: A target for immune-mediated inflammatory diseases (IMIDs)

The improved understanding of the molecular basis of innate immunity have led to the identification of type I interferons (IFNs), particularly IFN-α, as central mediators in the pathogenesis of several Immune-mediated inflammatory diseases (IMIDs) such as systemic lupus erythematosus (SLE), systemic sclerosis, inflammatory myositis and Sjögren's syndrome. Here, we review the main data regarding the opportunity to target type I IFNs for the treatment of IMIDs. Type I IFNs and their downstream pathways can be targeted pharmacologically in several manners. One approach is to use monoclonal antibodies against IFNs or the IFN-receptors (IFNARs, such as with anifrolumab). The downstream signaling pathways of type I IFNs also contain several targets of interest in IMIDs, such as JAK1 and Tyk2. Of these, anifrolumab is licensed and JAK1/Tyk2 inhibitors are in phase III trials in SLE. Targeting IFN-Is for the treatment of SLE is already a reality and in the near future may prove useful in other IMIDs. IFN assays will find a role in routine clinical practice for the care of IMIDs as further validation work is completed and a greater range of targeted therapies becomes available.

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.

Epidemiology of Sjögren syndrome

Sjögren syndrome is a phenotypically varied autoimmune disorder that can occur alone in primary Sjögren syndrome or in association with other connective tissue diseases (CTDs), including rheumatoid arthritis, systemic lupus erythematosus (SLE) and systemic sclerosis (SSc). The estimation of the prevalence and incidence of Sjögren syndrome varies depending on diagnostic criteria and study design, making it difficult to estimate geographical and temporal trends. Nonetheless, disease phenotype is influenced by geographical origin, which is a risk factor for systemic activity. Whether mortality in primary Sjögren syndrome is increased compared with that of the general population is not yet known, but extra-glandular manifestations, in particular lymphomas, are clear risk factors for mortality. In CTDs associated with Sjögren syndrome, lymphoma risk seems higher than that of patients with CTD alone, and there is potentially lower disease activity in SLE with Sjögren syndrome and in SSc with Sjögren syndrome than in SLE or SSc alone.

Prognostic significance of lymphocytic foci composition in minor salivary gland biopsies for severe disease flare and severity in Sjögren's syndrome: a 3-year follow-up cohort study

Introduction

This was an ambispective cohort study evaluating the prognostic significance of lymphocytic foci and its lymphoid composition in minor salivary gland biopsy (MSGB) for short-term disease flare and severity in Sjögren's syndrome (SS).

Methods

The inclusion criteria comprised individuals meeting the ACR/EULAR 2016 criteria who underwent MSGB with an infiltration of more than 50 lymphocytes and received clinical diagnosis between September 2017 and December 2018. Patients with inadequate biopsy samples were excluded. The number of lymphocytic foci and their lymphoid composition in MSGB were assessed using immunofluorescence staining. Major organ damage and improvements in the EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI) were measured. Statistical analyses, including Cox and linear regressions, were conducted.

Results

A total of 78 patients with at least one lymphocytic focus were included in the study. The presence of higher T-cell counts in lymphocytic foci in MSGB was associated with severe disease flare, and a logarithmic transformation of T-cell count indicated increased risk (HR 1.96, 95% CI 0.91-4.21). Improvements in the ESSDAI were associated with higher total lymphocyte count and T- and B-cell numbers in the lymphoid composition of the lymphocytic foci. Seropositive patients exhibited higher T CD4+ cell numbers. Correlation analysis showed negative associations between age and lymphocytic foci and the T-cell count. Positive correlations were observed between antinuclear antibody (ANA) titers and total lymphocyte numbers.

Discussion

Patients with a higher number of T cells in the lymphocytic infiltrates of lymphocytic foci may have a two-fold risk of severe disease flare. The number of B cells and T CD4+ cells in the lymphocytic infiltrates of lymphocytic foci showed a weak but positive relation with the ESSDAI improvement during follow-up. Age and seropositivity appeared to influence the lymphoid composition of the lymphocytic foci.

Analysis of the saliva microbiome in patients with immunoglobulin G4-related disease

OBJECTIVES

This article aims to investigate the saliva microbiome in patients with immunoglobulin G4-related disease (IgG4RD) compared with primary Sjögren's syndrome (SS).

METHODS

Saliva samples were collected from 11 IgG4RD and 11 SS patients who visited IMSUT Hospital, The Institute of Medical Science, The University of Tokyo. Deoxyribonucleic acid (DNA) was extracted from the samples, and primers were used to amplify the V3-V4 regions of bacterial and archaeal 16S ribosomal RNA (rRNA) genes, which was then analysed by paired-end sequencing. Amplicon reads were processed using QIIME2 to generate representative sequences. The Greengenes database was used to identify the bacterial flora in each sample and compare them between groups.

RESULTS

The IgG4RD and SS groups exhibited differences in bacterial diversity. Cluster analyses of attributed classification groups by species and disease showed that IgG4RD and SS cases formed individual clusters. Significant differences in relative abundance between IgG4RD and SS were observed for the following organisms: Mogibacterium (P = .0051), Solobacterium moorei (P = .0195), Slackia (P = .0356), and Moryella (P = .0455).

CONCLUSIONS

Salivary microbiome analysis of IgG4RD and SS patients revealed significantly higher relative proportions of Mogibacterium, S. moorei, Slackia, and Moryella bacteria in IgG4RD compared with SS.

TLR7 activation of age-associated B cells mediates disease in a mouse model of primary Sjögren's disease

Primary Sjögren's disease (pSD) (also referred to as Sjögren's syndrome) is an autoimmune disease that primarily occurs in women. In addition to exocrine gland dysfunction, pSD patients exhibit B cell hyperactivity. B cell-intrinsic TLR7 activation is integral to the pathogenesis of systemic lupus erythematosus, a disease that shares similarities with pSD. The role of TLR7-mediated B cell activation in pSD, however, remains poorly understood. We hypothesized that age-associated B cells (ABCs) were expanded in pSD and that TLR7-stimulated ABCs exhibited pathogenic features characteristic of disease. Our data revealed that ABC expansion and TLR7 expression were enhanced in a pSD mouse model in a Myd88-dependent manner. Splenocytes from pSD mice showed enhanced sensitivity to TLR7 agonism as compared with those derived from control animals. Sort-purified marginal zone B cells and ABCs from pSD mice showed enhanced inflammatory cytokine secretion and were enriched for antinuclear autoantibodies following TLR7 agonism. Finally, IgG from pSD patient sera showed elevated antinuclear autoantibodies, many of which were secreted preferentially by TLR7-stimulated murine marginal zone B cells and ABCs. These data indicate that pSD B cells are hyperresponsive to TLR7 agonism and that TLR7-activated B cells contribute to pSD through cytokine and autoantibody production. Thus, therapeutics that target TLR7 signaling cascades in B cells may have utility in pSD patients.

Ocular cicatricial pemphigoid: is there an association with autoimmune diseases?

PURPOSE

To assess the prevalence of autoimmune diseases (ADs) associated with ocular cicatricial pemphigoid (OCP) and analyze clinical, laboratory, and treatment associations between these entities.

METHODS

A multicentre cross-sectional study of patients with an OCP diagnosis. The population was divided into two groups according to their association with other ADs or not. Clinical, laboratory and treatment variables were described and compared between groups. A multivariable logistic regression analysis was performed to identify variables that could suggest the association between OCP and ADs.

RESULTS

Eighty-eight patients were recruited, with a mean age at diagnosis of 64.3 years (SD 11.9). Biopsy was performed in 86.8% of the patients. There was a median delay of 2 years from the onset of symptoms to diagnosis. Extraocular involvement was evidenced in 11.5%. The group associated with ADs included 24 patients (27.3%). The most prevalent diagnosis was Sjögren´s syndrome. Hypergammaglobulinemia was associated with ADs and OCP, adjusted for age, sex, smoking, skin and mucosal involvement, and erythrocyte sedimentation rate (OR 8.7; 95%CI 1.6-46.8; p = 0.012).

CONCLUSIONS

Due to OCP's autoimmune nature, it could coexist with other ADs. This study observed that more than a quarter of the population presented with this association, and hypergammaglobulinemia could suggest it.

Choroidal, retinal, and optic nerve changes in rheumatoid arthritis and primary sjogren's syndrome patients: comparıson with each other and healthy subjects

PURPOSE

The present study aims to evaluate the optic nerve, macula, and choroidal changes in both rheumatoid arthritis (RA) and primary Sjögren's syndrome (SjS) patients, and to compare these findings with age-matched healthy volunteers.

METHODS

This study included 46 RA patients, 33 primary SjS patients, and 37 age-matched healthy volunteers. All of the patients underwent a thorough ophthalmological examination, during which measurements of the retinal nerve fiber layer (RNFL), ganglion cell layer(GCL), and subfoveal choroidal thickness (CT) were taken using OCT (optical coherence tomography). The measurements taken from the right eye of each patient were used to compare among the groups.

RESULTS

RNFL thickness in superior quadrant was found to be statistically significantly thinner in the eyes with RA when compared to the control group (p = 0.022). In the nasal quadrant, the RNFL thickness was significantly thinner in patients with primary SjS compared to healthy individuals (p = 0.036). Also, the temporal quadrant RNFL was significantly thinner in RA patients than in the primary SjS patients (p = 0.033). GCL thickness was observed to be thinner in all quadrants of both RA and primary SjS groups compared to the control group. However, the difference was not found to be statistically significant. Subfoveal CT was observed to be thicker in RA and SjS groups compared to the control group, but this difference was also not statistically significant.

CONCLUSION

Systemic autoimmune diseases like RA and primary SjS can lead to a decrease in RNLF and GCL thickness, which can impair visual acuity even in the absence of ocular symptoms. Therefore, monitoring changes in the optic nerve, retina, and choroid layer are crucial in these patients.

Association between primary Sjögren's syndrome and gut microbiota disruption: a systematic review and meta-analysis

Evidence of gut microbiota disruption for numerous autoimmune diseases has accumulated. Recently, the relationship between the microbiota and primary Sjögren's disease has been increasingly investigated but has yet to be systematically elucidated. Therefore, a meta-analysis of publications dealing on topic was conducted. Case-control studies comparing primary Sjögren's syndrome patients and healthy controls (HCs) were systematically searched in nine databases from inception to March 1, 2023. The primary result quantitatively evaluated in this meta-analysis was the α-diversity. The secondary results qualitatively extracted and analyzed were the β-diversity and relative abundance. In total, 22 case-control studies covering 915 pSS patients and 2103 HCs were examined. The quantitative analysis revealed a slight reduction in α-diversity in pSS patients compared to HCs, with a lower Shannon-Wiener index (SMD =  - 0.46, (- 0.68, - 0.25), p < 0.0001, I2 = 71%), Chao1 richness estimator (SMD =  - 0.59, (- 0.86, - 0.32), p < 0.0001, I2 = 81%), and ACE index (SMD =  - 0.92, (- 1.64, - 0.19), p = 0.01, I2 = 86%). However, the Simpson index (SMD = 0.01, (- 0.43, 0.46) p = 0.95, I2 = 86%) was similar in the two groups. The β-diversity significantly differed between pSS patients and HCs. Variations in the abundance of specific microbes and their metabolites and potential functions contribute to the pSS pathogenesis. Notably, the abundance of the phylum Firmicutes decreased, while that of Proteobacteria increased. SCFA-producing microbes including Ruminococcaceae, Lachnospiraceae, Faecalibacterium, Butyricicoccus, and Eubacterium hallii were depleted. In addition to diversity, the abundances of some specific microbes were related to clinical parameters. According to this systematic review and meta-analysis, gut microbiota dysbiosis, including reduced diversity, was associated with proinflammatory bacterium enrichment and anti-inflammatory bacterium depletion in pSS patients. Further research on the relationship between the gut microbiota and pSS is warranted.

Imaging of Vasculitis Associated with Systemic Disease

Vasculitides are characterized by inflammation of the vessel wall, with their categorization relying on clinical and paraclinical manifestations, vessel type, size, distribution, histological attributes, and associated conditions. This review delves into the salient neuroimaging hallmarks of central nervous system vasculitis associated with the most prevalent systemic diseases and highlightings potential pitfalls and diagnostic confounders.

Multimodal Single-Cell Sequencing of B Cells in Primary Sjögren's Syndrome

OBJECTIVE

B cells are important in the pathogenesis of primary Sjögren's syndrome (pSS). Patients positive for Sjögren's syndrome antigen A/Sjögren syndrome antigen B (SSA/SSB) autoantibodies are more prone to systemic disease manifestations and adverse outcomes. We aimed to determine the role of B cell composition, gene expression, and B cell receptor usage in pSS subgroups stratified for SSA/SSB antibodies.

METHODS

Over 230,000 B cells were isolated from peripheral blood of patients with pSS (n = 6 SSA-, n = 8 SSA+ single positive and n = 10 SSA/SSB+ double positive) and four healthy controls and processed for single-cell RNA sequencing (scRNA-seq) and single-cell variable, diversity, and joining (VDJ) gene sequencing (scVDJ-seq).

RESULTS

We show that SSA/SSB+ patients present the highest and lowest proportion of naïve and memory B cells, respectively, and the highest up-regulation of interferon-induced genes across all B cell subtypes. Differential usage of IGHV showed that IGHV1-69 and IGHV4-30-4 were more often used in all pSS subgroups compared with controls. Memory B cells from SSA/SSB+ patients displayed a higher proportion of cells with unmutated VDJ transcripts compared with other pSS patient groups and controls, indicating altered somatic hypermutation processes. Comparison with previous studies revealed heterogeneous clonotype pools, with little overlap in CDR3 sequences. Joint analysis using scRNA-seq and scVDJ-seq data allowed unsupervised stratification of patients with pSS and identified novel parameters that correlated to disease manifestations and antibody status.

CONCLUSION

We describe heterogeneity and molecular characteristics in B cells from patients with pSS, providing clues to intrinsic differences in B cells that affect the phenotype and outcome and allowing stratification of patients with pSS at improved resolution.

Immunolocalization patterns of histone-deacetylases in salivary glands of mice during postnatal development

OBJECTIVE

Histone-deacetylases (HDACs) are epigenetic modulators involved in the control of gene expression. No data are available on the expression or subcellular localization of HDACs in salivary glands. The present study aims to examine the subcellular distribution of HDACs in salivary glands during postnatal development.

DESIGN

The major salivary glands of C57/BL6 mice were separately removed at 10, 25, 30,60 and 90 days after birth. Hematoxylin-eosin (H&E) and immunohistochemical staining were performed for HDACs. Gene Expression of HDACs in C57BL/6. NOD-Aec1Aec2 mice salivary glands during the development of Sjögren's syndrome-like illness were also analyzed by using the gene expression datasets (GSE 15640).

RESULTS

In the mice salivary gland, HDACs were found to have different localization patterns at various stages of development (10, 25, 30, 60, and 90 days). Apart from HDAC6, ductal cells of salivary glands were the primary sites for HDAC localization. HDAC2, 8, 5, 10 and 11 were expressed at high levels in the salivary gland after birth while HDAC6 showed no expression during postnatal development. This suggests that these HDAC subtypes may have different roles in salivary gland function. In the context of Sjögren's syndrome-like illness, HDAC 2, 8 and 10 showed low expression while HDAC1, 6,5,3 and 11 had relatively high expression in the salivary gland.

CONCLUSIONS

This study has provided an important reference for understanding the spatiotemporal-specific expression of HDACs in the salivary gland. These results offer new clues for the experimenters and hold promise for developing innovative therapeutic strategies for salivary gland-related diseases.

Claudin-10 Decrease in the Submandibular Gland Contributes to Xerostomia

Tight junction proteins play a crucial role in paracellular transport in salivary gland epithelia. It is clear that severe xerostomia in patients with HELIX syndrome is caused by mutations in the claudin-10 gene. However, little is known about the expression pattern and role of claudin-10 in saliva secretion in physical and disease conditions. In the present study, we found that only claudin-10b transcript was expressed in human and mouse submandibular gland (SMG) tissues, and claudin-10 protein was dominantly distributed at the apicolateral membranes of acini in human, rat, and mouse SMGs. Overexpression of claudin-10 significantly reduced transepithelial electrical resistance and increased paracellular transport of dextran and Na+ in SMG-C6 cells. In C57BL/6 mice, pilocarpine stimulation promoted secretion and cation concentration in saliva in a dose-dependent increase. Assembly of claudin-10 to the most apicolateral portions in acini of SMGs was observed in the lower pilocarpine (1 mg/kg)-treated group, and this phenomenon was much obvious in the higher pilocarpine (10 mg/kg)-treated group. Furthermore, 7-, 14-, and 21-wk-old nonobese diabetic (NOD) and BALB/c mice were used to mimic the progression of hyposalivation in Sjögren syndrome. Intensity of claudin-10 protein was obviously lower in SMGs of 14- and 21-wk-old NOD mice compared with that of age-matched BALB/c mice. In the cultured mouse SMG tissues, interferon-γ (IFN-γ) downregulated claudin-10 expression. In claudin-10-overexpressed SMG-C6 cells, paracellular permeability was decreased. Furthermore, IFN-γ stimulation increased p-STAT1 level, whereas pretreatment with JAK/STAT1 antagonist significantly alleviated the IFN-γ-induced claudin-10 downregulation. These results indicate that claudin-10 functions as a pore-forming component in acinar epithelia of SMGs, assembly of claudin-10 is required for saliva secretion, and downregulation of claudin-10 induces hyposecretion. These findings may provide new clues to novel therapeutic targets on hyposalivation.

Herpesviridae, Neurodegenerative Disorders and Autoimmune Diseases: What Is the Relationship between Them?

Alzheimer's disease and Parkinson's disease represent the most common forms of cognitive impairment. Multiple sclerosis is a chronic inflammatory disease of the central nervous system responsible for severe disability. An aberrant immune response is the cause of myelin destruction that covers axons in the brain, spinal cord, and optic nerves. Systemic lupus erythematosus is an autoimmune disease characterized by alteration of B cell activation, while Sjögren's syndrome is a heterogeneous autoimmune disease characterized by altered immune responses. The etiology of all these diseases is very complex, including an interrelationship between genetic factors, principally immune associated genes, and environmental factors such as infectious agents. However, neurodegenerative and autoimmune diseases share proinflammatory signatures and a perturbation of adaptive immunity that might be influenced by herpesviruses. Therefore, they might play a critical role in the disease pathogenesis. The aim of this review was to summarize the principal findings that link herpesviruses to both neurodegenerative and autoimmune diseases; moreover, briefly underlining the potential therapeutic approach of virus vaccination and antivirals.

SLAMF3 promotes Th17 differentiation and is reversed by iguratimod through JAK1/STAT3 pathway in primary Sjögren's syndrome

OBJECTIVE

The signaling lymphocytic activation molecule family of receptors (SLAMF) is involved in the activation of T cells and plays important roles in the pathogenesis of autoimmune diseases. The purpose of this study is to observe the expression of SLAMF3 on CD4 + T cells and its effect on the differentiation of T helper 17 (Th17) in primary Sjögren's syndrome (pSS). Furthermore, we found iguratimod (IGU) could effectively reverse the aberrant Th17 differentiation through JAK1/STAT3 signaling.

METHODS

Peripheral blood mononuclear cells from 40 pSS and 40 healthy control subjects were enrolled for analysis of expression of SLAMF3 on CD4 + T and Th17 cells by flow cytometry. Serum IL-17 and SLAMF3 were detected by ELISA assay. Labial biopsies from 20 pSS patients and 20 non-pSS controls were performed immunohistochemical for staining expression of CD4, IL-17, and SLAMF3. Under the priming conditions with anti-CD3/CD28 or CD3/SLAMF3 antibodies on CD4 + T cells extracted from pSS and controls, the proportion of Th17 cells in CD4 + T cells and the amount of soluble IL-17A were assessed by flow cytometry and ELISA. Furthermore, RNA sequencing was performed for the transcriptomics study. Additionally, RNA level of RORγt and IL-17A and the protein level of RORγt, p-JAK1 and p-STAT3, were detected by real-time PCR and western blot.

RESULTS

The expression levels of SLAMF3 on CD4 + T and Th17 cells in the peripheral blood and salivary glands in pSS patients were significantly elevated than that in control groups. The serum IL-17A and SLAMF3 in pSS patients were much higher compared with the control group. Although co-stimulation of CD3/SLAMF3 could promote CD4 + T cells differentiate into Th17 cells both in pSS and controls, the CD4 + T cells from pSS have a more sensitive response in Th17 differentiation with the SLAMF3 stimulation. Transcriptomics results showed the CD3/SLAMF3 stimulation caused the activation of Th17 signaling and JAK1/STAT3 pathway. Quantitative PCR and western blotting confirmed the IGU (iguratimod), which is a safe clinical drug in treatment of autoimmune diseases, effectively reversed the increased Th17 proportion, the expression levels of RORγt, pJAK1, and pSTAT3 caused by CD3/SLAMF3 stimulation.

CONCLUSION

SLAMF3 upregulates Th17 cell differentiation of CD4 + T cells and IL-17A secretion through enriching RORγt and activating the transcriptomics participating in the pathogenesis of primary Sjögren's syndrome. IGU could inhibit the process through this therapeutic target in pSS.

The role of epithelial cells in the immunopathogenesis of Sjögren's syndrome

Sjögren's syndrome is a systemic autoimmune disease characterized by dysfunction of the affected exocrine glands. Lymphocytic infiltration within the inflamed glands and aberrant B-cell hyperactivation are the two salient pathologic features in Sjögren's syndrome. Increasing evidence indicates that salivary gland epithelial cells act as a key regulator in the pathogenesis of Sjögren's syndrome, as revealed by the dysregulated innate immune signaling pathways in salivary gland epithelium and increased expression of various proinflammatory molecules as well as their interaction with immune cells. In addition, salivary gland epithelial cells can regulate adaptive immune responses as nonprofessional antigen-presenting cells and promote the activation and differentiation of infiltrated immune cells. Moreover, the local inflammatory milieu can modulate the survival of salivary gland epithelial cells, leading to enhanced apoptosis and pyroptosis with the release of intracellular autoantigens, which further contributes to SG autoimmune inflammation and tissue destruction in Sjögren's syndrome. Herein, we reviewed recent advances in elucidating the role of salivary gland epithelial cells in the pathogenesis of Sjögren's syndrome, which may provide rationales for potential therapeutic targeting of salivary gland epithelial cells to alleviate salivary gland dysfunction alongside treatments with immunosuppressive reagents in Sjögren's syndrome.

Decreased expression of TIGIT on CD14 + monocytes correlates with clinical features and laboratory parameters of patients with primary Sjögren's syndrome

OBJECTIVES

The purpose of this study was to investigate the expression of T-cell immunoglobulin and ITIM domain (TIGIT) in peripheral circulation of primary Sjögren's syndrome (pSS) and its role in the development of pSS.

METHODS

The expression of TIGIT on T cells, B cells, natural killer (NK) cells, and CD14 + monocytes was detected by flow cytometry in pSS and healthy control (HC). The correlations between expression of TIGIT and clinical features and laboratory parameters of pSS were analyzed. Meanwhile, we analyzed the change in expression of TIGIT before and after treatment, and its role in the prognosis of pSS treatment was evaluated.

RESULTS

The expression of TIGIT on CD3 + , CD4 + , and CD8 + T cells increased and decreased on CD14 + monocytes in pSS compared to HC; however, there was no significance of B lymphocytes and NK cells. The correlation analysis between the expression of TIGIT on T lymphocytes and CD14 + monocytes and clinical features of pSS showed that the decrease in TIGIT expression on CD14 + monocytes was more closely related to pSS. The expression of TIGIT + CD14 + monocytes negatively correlated with the disease activity of pSS. The expression of TIGIT + CD14 + monocytes of pSS with arthralgia, fatigue, decayed tooth, xerostomia, interstitial lung disease, anti-Ro52 positive, and high IgG decreased compared to that in negative patients. Furthermore, it was significantly lower in active patients than in nonactive patients. After treatment, the expression of TIGIT + CD14 + monocytes tended to increase.

CONCLUSION

Our study suggested that decreased TIGIT expression on CD14 + monocytes was associated with the clinical manifestations, disease activity, and prognosis of pSS patients. TIGIT + CD14 + monocytes may present as a potential target and a biomarker of the prognosis for immunomodulatory therapy in pSS. Key Points • The expression of TIGIT+CD14+ monocytes significantly decreased in pSS patients compared to HC. • There was a negative correlation between TIGIT+CD14+ monocytes and the disease activity of pSS. • TIGIT+CD14+ monocyte expression was associated with the clinical manifestations, autoantibodies, IgG, and prognosis of pSS patients.

Is minor salivary gland biopsy still mandatory in Sjogren's syndrome? Does seronegative Sjogren's syndrome exist?

Sjӧgren's disease (SjD) is a systemic autoimmune disorder characterized by the chronic inflammation and dysfunction of exocrine glands, mainly salivary glands, causing dryness of the eyes and of the mouth. The disease may affect different organs and tissues with complex and heterogeneous clinical presentation, usually with sicca symptoms, profound fatigue, chronic pain, major organ involvement, and lymphomas. SjD diagnosis is based on the combination of clinical, serological, and functional tests with histological biomarkers. Minor salivary gland biopsy (mSGB) represents the cornerstone for the diagnosis of SjD, allowing the study of the characteristic focal infiltration of B- and T lymphocytes. Besides, mSGB might also have a prognostic role, being the infiltrates more complex in patients with severe SjD. But biopsy, so far, is not mandatory for SjD and mSG ultrasound and peripheral biomarkers might replace its role in the future. Another important aspect of SjD is the presence of autoantibodies, although 20 to 30% of patients are "seronegative" for specific autoantibodies (ANA, antiRo/SSA, antiLa/SSB). The characteristics of this subset of patients are currently under evaluation and "new" autoantibodies and biomarkers might be necessary for better patient's stratification and follow-up.

Evidence of a Sjögren's disease-like phenotype following COVID-19 in mice and humans

Sjögren's Disease (SjD) is a systemic autoimmune disease characterized by lymphocytic inflammation of the lacrimal and salivary glands (SG), dry eyes and mouth, and systemic symptoms. SARS-CoV-2 may trigger the development or progression of autoimmune diseases. To test this, we used a mouse model of SARS-CoV-2 infection and convalescent patients' blood and SG in order to understand the development of SjD-like autoimmunity after infection. First, SARS-CoV-2-infected human angiotensin-converting enzyme 2 (ACE2) transgenic mice exhibited decreased salivation, elevated antinuclear antibodies (ANA), and lymphocytic infiltration in the lacrimal and SG. The sera from patients with COVID-19 sera showed increased ANA (i.e., anti-SSA [Sjögren's-syndrome-related antigen A]/anti-Ro52 and anti-SSB [SS-antigen B]/anti-La). Male patients showed elevated anti-SSA compared with female patients, and female patients exhibited diverse ANA patterns. SG biopsies from convalescent COVID-19 patients were microscopically similar to SjD SG with focal lymphocytic infiltrates in 4 of 6 patients and 2 of 6 patients exhibiting focus scores of at least 2. Lastly, monoclonal antibodies produced in recovered patients blocked ACE2/spike interaction and cross-reacted with nuclear antigens. Our study shows a direct association between SARS-CoV-2 and SjD. Hallmark features of SjD-affected SGs were histologically indistinguishable from convalescent COVID-19 patients. The results implicate that SARS-CoV-2 could be an environmental trigger for SjD.

[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.

The Potential Utility of Salivary and Tear Proteomics to Discriminate Sjögren's Disease from Non-Sjögren's Sicca

Sjögren's Disease (SjD) is an autoimmune disorder associated with decreased saliva and/or tear secretions, resulting in patients reporting dryness in the mouth and eyes. Serum autoantibodies directed against the Ro60/SS-A and La/SS-B autoantigens are a distinctive feature of the disease. Analysis of the saliva and tear proteomes represents one promising alternative method of both classifying and monitoring the condition, and research into salivary and tear proteomics in patients with SjD, with and without sicca, has shown its efficacy and practicality in both clinical and research settings. Studies analyzing the saliva proteomics of SjD patients have generally shown an overexpression of proteins involved in T-cell activation, the immune response, β-2 microglobulin, and the recruitment of pro-inflammatory agents. These studies also show a decrease in or downregulation of proteins involved in salivary secretion. Studies analyzing the tear proteomics of patients with SjD have generally indicated an upregulation of proteins involved with TNF-α signaling, B-cell survival, and the recruitment of pro-inflammatory agents. Studies also note the differential expression of tear protein folding as a hallmark of ocular involvement in this condition. These findings help to elucidate the biochemical relationship between the proteomes of saliva/tear fluids and the general pathophysiology of the gland involved with the pathogenesis of this condition, giving further credence to the potential role of salivary and tear proteomics in the future of diagnosis and treatment for patients with SjD.

Significant association of CX3CR1+CD8 T cells with aging and distinct clinical features in Sjögren's syndrome and IgG4-related disease

OBJECTIVES

Recent studies have implicated cytotoxic CD4 and CD8 T cells in primary Sjögren's syndrome (pSS) and IgG4-related disease (IgG4-RD), but their association with immune aging and organ-specific clinical features remain unclear. CX3CR1 is expressed on cytotoxic CD4 and CD8 T cells. The aim of this study was to determine associations of peripheral CX3CR1+CD4 and CX3CR1+CD8 T cells with aging and clinical features.

METHODS

Whole blood samples were freshly obtained from consecutive patients with active, treatment-naïve pSS (n=57), IgG4-RD (n=54), and healthy individuals (n=40) and analysed by flow cytometry for CX3CR1+CD4 and CX3CR1+CD8 proportions. Associations of those T cells with aging and clinical features were determined.

RESULTS

CX3CR1+CD4 and CX3CR1+CD8 T cells selectively expressed perforin and granzyme B. Proportions of CX3CR1+CD4 and CX3CR1+CD8 T cells were significantly higher in pSS and IgG4-RD than in healthy individuals. Higher proportions of CX3CR1+CD8 T cells were associated with aging in pSS and IgG4-RD but not in healthy individuals. Sex differences were not associated with proportions of CX3CR1+CD8 T cells. Furthermore, patients with pSS with interstitial lung disease showed higher proportions of CX3CR1+CD8 T cells than those without interstitial lung disease. IgG4-RD patients with retroperitoneal fibrosis and/or aortitis exhibited higher proportions of CX3CR1+CD8 T cells compared with those with Mikulicz's disease. Moreover, proportions of CX3CR1+CD8 T cells were decreased following glucocorticoid treatment in paralleled with clinical improvements in IgG4-RD.

CONCLUSIONS

CX3CR1+CD8 T cells might be involved in immune aging and distinct clinical phenotypes of patients with pSS or IgG4-RD.

Increased proportion of CD226 + CD14 + monocytes correlates with clinical features and laboratory parameters in patients with primary Sjögren's syndrome

OBJECTIVES

CD226 is widely expressed on the surface of immune cells as a co-stimulatory receptor, which is involved in the development of many autoimmune diseases. The purpose of this study was to investigate the proportion of CD226 on CD14 + monocytes in the peripheral circulation of patients with primary Sjögren's syndrome (pSS) and the clinical significance of pSS.

METHODS

The proportion of CD226 on the surface of CD14 + monocytes was measured by flow cytometry in 45 pSS patients and 25 healthy controls (HC). The correlations between the proportion of CD226 + CD14 + monocytes and the clinical features and laboratory parameters of pSS were analyzed. Meanwhile, we analyzed the change in proportion of CD226 + CD14 + monocytes before and after treatment, and the clinical significance of pSS was evaluated.

RESULTS

The proportion of CD226 on CD14 + monocytes markedly increased in pSS patients compared to HC (p < .01). We found the proportion of CD226 + CD14 + monocytes was positively correlated with the disease activity and severity of pSS patients. The proportion of CD226 + CD14 + monocytes in pSS patients with decayed tooth, fatigue, interstitial lung disease (ILD), low WBC, high IgG, anti-Ro60, and anti-SSB positive increased compared to that in negative patients (p < .05). Furthermore, the proportion of CD226 + CD14 + monocytes was significantly higher in active patients than in nonactive patients (p < .01). Additionally, the proportion of CD226 + CD14 + monocytes decreased in seven pSS patients after treatment (p < .01).

CONCLUSION

Our study suggested that an increased CD226 proportion on CD14 + monocytes was associated with the clinical manifestations, disease activity, and prognosis of pSS patients. CD226+ CD14 + monocytes may present a potential target and a biomarker for the prognosis and therapy of pSS patients.

Nuts and bolts of salivary gland pathology in primary Sjögren's syndrome

Primary Sjögren's syndrome (pSS) is a chronic, systemic, inflammatory autoimmune disease characterised by lymphocyte proliferation and progressive damage to exocrine glands. Salivary gland histopathology based on salivary gland biopsy is relevant for the diagnosis of pSS and therefore broadly applied in clinical practice. Tissue can be obtained from labial salivary glands (LSG) biopsy or from major salivary glands (MSG) biopsy, namely the parotid; in this latter scenario, the procedure can be either an open surgical biopsy or a US guided core needle biopsy.In this review we will: i) present the histopathological findings that may be encountered by pathologists on biopsies from pSS patients; ii) discuss the advantages and disadvantages of the surgical and/or imaging guided procedures to obtain tissues from LSG or MSG; iii) describe the histopathological features of lymphoma of MSG in pSS patients.

Secretagogue effect of PDE4 inhibitor apremilast on human salivary gland organoids obtained from primary Sjögren's syndrome patients

OBJECTIVES

The aim of the study was to culture vital salivary gland organoids obtained through labial or parotid biopsy of primary Sjögren's syndrome (pSS) patients in order to evaluate their morphological and functional features in basal condition and after stimulation with Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) activator forskolin and phosphodiesterase 4 (PDE4) inhibitor apremilast, their in vitro regenerative capacity and the immune-histological resemblance with original tissue.

METHODS

Salivary gland tissues from five pSS patients were processed to obtain vital organoids; swelling assay and cell proliferation tests were performed after forskolin and apremilast application. Immunochemistry evaluation on original salivary gland tissue and corresponding organoids was performed, and secretomics analysis was conducted to assess their functional status.

REULTS

After application of forskolin and apremilast, we observed organoid swelling after 30 minutes, compatible with a positive functional status and enhancement of saliva production. In 3 cases, apremilast induced organoid proliferation. All cases were positive for cytokeratin 14 (CK14) and most for cytokeratin 5 (CK5). All the cases were positive for amylase; its secretion, and thus functional status of organoids, was confirmed by its high concentration in the culture medium. A focal ductal differentiation was found in some cases, highlighted by epithelial membrane antigen (EMA) positivity. The more differentiated EMA positive areas were negative for the staminal marker CK14, showing a sort of "complementary staining".

CONCLUSIONS

Our data highlighted that differentiated cells and vital functional organoids that recapitulate the development of original salivary glands can be obtained from pSS epithelium. For the first time, the direct stimulating effect of PDE4 inhibitor apremilast on pSS human salivary gland organoids is reported, opening new perspectives on targeting oral dryness with drugs that combine secretagogue and immunomodulatory effects.

IL-27 regulates NLRP3 inflammasome activation of MDSCs in experimental Sjögren's syndrome

Excessive NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome activation has an important function in the pathogenesis of Sjögren's syndrome (SS). Increased and dysfunctional myeloid-derived suppressor cells (MDSCs) promoted SS. However, NLRP3 inflammasome activation of MDSCs in SS and its regulated components are unclear. Splenic MDSCs were purified by immunomagnetic beads and cultured. Western blot was used to assess NLRP3 inflammasomes. Interleukin-1β (IL-1β) and IL-18 were measured using enzyme-linked immunosorbent assay. Here we showed that the NLRP3 inflammasome was activated in non-obese diabetic (NOD) mice with SS-like manifestations. We found that NLRP3 inflammasome activation was augmented in MDSCs of SS mice and NLRP3 inflammasome activation was suppressed in IL-27-deficient NOD mice. Consistent with findings of SS mice in vivo, we observed that NLRP3 inflammasome activation by adenosine triphosphate and lipopolysaccharide was remarkably intensified in MDSCs with IL-27 treatment in vitro. Collectively, our data highlighted that IL-27 regulates NLRP3 inflammasome activation of MDSCs in experimental SS.

Characterisation of macrophage infiltration and polarisation based on integrated transcriptomic and histological analyses in Primary Sjögren's syndrome

Background

Primary Sjögren's syndrome (pSS) is a progressive inflammatory autoimmune disease. Immune cell infiltration into glandular lobules and ducts and glandular destruction are the pathophysiological hallmarks of pSS. Macrophages are one of the most important cells involved in the induction and regulation of an inflammatory microenvironment. Although studies have reported that an abnormal tissue microenvironment alters the metabolic reprogramming and polarisation status of macrophages, the mechanisms driving macrophage infiltration and polarisation in pSS remain unclear.

Methods

Immune cell subsets were characterised using the single-cell RNA sequencing (scRNA-seq) data of peripheral blood mononuclear cells (PBMCs) from patients with pSS (n = 5) and healthy individuals (n = 5) in a public dataset. To evaluate macrophage infiltration and polarisation in target tissues, labial salivary gland biopsy tissues were subjected to histological staining and bulk RNA-seq (pSS samples, n = 24; non-pSS samples, n = 12). RNA-seq data were analysed for the construction of macrophage co-expression modules, enrichment of biological processes and deconvolution-based screening of immune cell types.

Results

Detailed mapping of PBMCs using scRNA-seq revealed five major immune cell subsets in pSS, namely, T cells, B cells, natural killer (NK) cells, dendritic cells (DCs) and monocyte-macrophages. The monocyte-macrophage subset was large and had strong inflammatory gene signatures. This subset was found to play an important role in the generation of reactive oxygen species and communicate with other innate and adaptive immune cells. Histological staining revealed that the number of tissue-resident macrophages was high in damaged glandular tissues, with the cells persistently surrounding the tissues. Analysis of RNA-seq data using multiple algorithms demonstrated that the high abundance of pro-inflammatory M1 macrophages was accompanied by the high abundance of other infiltrating immune cells, senescence-associated secretory phenotype and evident metabolic reprogramming.

Conclusion

Macrophages are among the most abundant innate immune cells in PBMCs and glandular tissues in patients with pSS. A bidirectional relationship exists between macrophage polarisation and the inflammatory microenvironment, which may serve as a therapeutic target for pSS.

Ro52/TRIM21 - From host defense to autoimmunity

Ro52 (TRIM21) belongs to the ubiquitin ligase family. This protein plays a crucial role in many immunological processes, including antibody-dependent intracellular neutralization, synergy with the complement system, antiviral response, death mediation, oxidative stress response, and protein ubiquitination. Abnormal expression of TRIM21 can break immunological tolerance and lead to the production of autoantibodies against TRIM21. Antibodies against TRIM21 are detected in various autoimmune diseases, including Sjögren's syndrome (SS), systemic lupus erythematosus (SLE), or myositis. However, anti-TRIM21 presence is not limited to autoimmune connective tissue disorders. It was observed in patients with malignancies, various cancerous processes, infectious diseases, and idiopathic interstitial pneumonia. The occurrence of TRIM21 autoantibodies is also associated with clinical features, such as the prevalence of interstitial lung diseases and cardiac or haematological involvement in connective tissue disorders. The purpose of this review was to summarize current knowledge of the immunological functions of TRIM21 and analyze the clinical implications of anti-TRIM21 antibodies in the disease course.

Pulmonary adverse events of breast silicone implants and silicone injection

The incidence of breast implants and silicone injections has continuously increased since their FDA approval for use in the 1960's. The prevalence of overall adverse events is approximately 20%. The actual incidence of pulmonary adverse events is unknown. This review focuses on the pulmonary adverse events of breast implants and silicone injections. Vascular complications are represented by acute and chronic embolisation syndromes with a clinico-radiological presentation of alveolar hemorrhage. Inflammatory complications are numerous, including siliconoma, which is a granulomatous reaction mimicking a mesothelioma. On the other hand, there are some reports arguing a link between the development of auto-immune diseases and breast implants, such as scleroderma, rheumatoid arthritis, Sjögren's syndrome, and dermatomyositis. Finally, for patients with asthma, breast implants may contribute to poor disease control. Cases of eosinophilic granulomatosis with polyangeitis have been described. Thus, it is of interest to decipherate mechanisms and incidence of these effects in prospective studies to better manage pulmonary diseases in patients wearing breast implants in order to understand their role as culprits or bystanders. In addition, characterization of subpopulations with increased risk of adverse events is needed as we highlighted that some subpopulations seem to be at greater risk of developing them, notably asthmatics.

Uncovering potential new biomarkers and immune infiltration characteristics in primary Sjögren's syndrome by integrated bioinformatics analysis

Primary Sjögren's syndrome (pSS) is known as autoimmune disease characterized by damage to endocrine glands, such as the salivary and lacrimal glands. This study aimed to identify potential biomarkers for pSS using integrated bioinformatics analysis and explore the relationship between differentially expressed genes (DEGs) and immune infiltration. Three pSS datasets (GSE7451, GSE23117, and GSE40611) from the gene expression omnibus database were integrated. All the datasets were processed in R (version 4.0.3). A total of 16 immune cells and 13 immune functions were obtained. The top immune cell and immune function were "activated" dendritic cells and major histocompatibility complex class I. Correlation analysis showed the top correlation among 16 immune cells were B cells and tumor infiltrating lymphocytes, check-point and T cell co-stimulation, respectively. In comparisons of immune score, "activated" dendritic cells (.657 vs 594, P < .001), B cells (.492 vs 434, P = .004), macrophages (.631 vs 601, P = .010), inflammation-promoting (.545 vs 478, P < .001), Type I interferon Reponse (.728 vs 625, P < .001) and so on were higher in pSS than control group. In correlation analysis, the up-regulation of interferon induced protein with tetratricopeptide repeats 1 gene was strongly correlated with Type I interferon response with a correlation coefficient of .87. The receiver operating characteristic curve of 5 genes showed that the area under curve was.891. In the verification model, the area under curve was.881. In addition, disease ontology analysis supported the association between DEGs and pSS. In summary, pSS has a variety of DEGs in immune infiltration, which is worthy of the attention from clinicians.