GEOEPIDEMIOLOGY OF SJÖGREN'S SYNDROME. A 2020 UPDATE.
- Juan-Manuel Anaya, Colombia
NEUROLOGICAL INVOLVEMENT IN PRIMARY SJOGREN’S SYNDROME
- Roberto Gerli, Italy
THE EPSTEIN-BARR VIRUS INFECTION IN PRIMARY SJÖGREN’S SYNDROME
- Maria Maślińska, Poland
Abstract
Background and Aims
The Epstein-Barr virus (EBV) targets uman B lymphocytes and epithelial cells - also involved in primary Sjogren's syndrome pathogenesis - triggering autoimmune response. It is able to stimulate B cells and prolong their survival time (immortalization) with increase of polyclonal gamma globulin production. EBV exists in lytic and latent phases, the latter with the "concealment” of certain viral proteins.EBV induces in pSS through such mechanisms, as molecular mimicry, impaired EBV-specific T-cell response and activity of viral IL-10. In the latent phase, infected B-cells express latent proteins differentiating into a germinal center centrocyte and transforming to the memory stage.The aim of this study was to assess the EBV infection in pSS patients.
Methods
75 patients with pSS - Female (n=65; 87%); Male(n=10;13%); mean age 52±15SD. The profile of IgM/IgG specific to EBV proteins determined by ELISA test, distinguishing EBV infection status. The immunohistochemical assessment of a minor salivary glnads biopsy, analyzing the presence of CD3 +, CD4 +, CD19 + and CD21 + cells.
Results
2,7% (n=2) patients had no EBV contact, 70,7% - infection reactivation, 24% - past infection and 2,7% - active infection. In immunochemistry CD3+, CD4+ and CD 19+ cells present in reactivation and past infection groups without CD21+;CD 35+ presence.
Conclusions
The ractivation of EBV infection dominates in the pSS group. In the infiltrates the presence of T and B cells dominates, no markers of dendritic cells were found. This confirms the role of EBV in pSS; immunochemistry may confirm the role of EBV infection on B and T cell activation.
RISING INCIDENCE OF SJOGREN SYNDROME? OR JUST MORE SENSITIVE CLASSIFICATION CRITERIA?
- Katja Perdan Pirkmajer, Slovenia
Abstract
Background and Aims
Epidemiological data on primary Sjögren syndrome (pSS) are variable and depend on the diagnostic criteria. We determined the incidence rate of pSS in Slovenia using the 2002 American European (AE) and the new ACR/EULAR 2016 classification criteria.
Methods
We included 399 consecutive subjects (365 females, mean age 57.8 +/- 13.8, range: 21.4-88.5) referred for evaluation of pSS at our department, which provides rheumatology services for 704,000 adult residents. Subject assessment included questionnaire about ocular and oral involvement, Schirmer-I test, unstimulated salivary flow (USF) test, Rose Bengal scoring, immunoserological tests, and minor salivary gland biopsy. Gender- and age-specific pSS incidence rates were calculated based on the ACR/EULAR and the AE criteria.
Results
We identified 109 incipient cases of pSS (104 females) according to the ACR/EULAR criteria. Annual incidence rate was 5.2/100,000 adults (95% CI 4.3-6.2), 9.6/100,000 females (95% CI 7.9-11.6) and 0.5/100,000 males 0.5 (95% CI 0.2-1.1). Only 90/109 subjects also fulfilled the AE criteria. The discrepancy in the criteria fulfillment was mainly due to lack of objective sicca symptoms. The 109 subjects with pSS had anti-Ro antibodies in 72%, histologically positive focus score in 83%, while 57 % were positive for both.
Conclusions
The pSS incidence is higher than previously reported in Slovenia, possibly due to the higher sensitivity of the ACR/EULAR 2016 classification criteria in our cohort.
PROGENITOR CELL NICHE SENESCENCE REFLECTS PATHOLOGY OF THE PAROTID SALIVARY GLAND IN PRIMARY SJÖGREN’S SYNDROME
- Sarah Pringle, Netherlands
Abstract
Background and Aims
Background and aims: SG (SG) progenitor cells (SGPCs) maintain SG homeostasis. We have previously shown that in primary Sjögren’s syndrome (pSS), SGPCs are likely to be senescent, and may underpin SG dysfunction. This study assessed the extent of senescence of cells in a SGPC niche in pSS patient SGs, and its correlation with functional and clinical parameters.
Methods
Methods p16 and p21 expression as markers of senescence in both total SG epithelium and a SGPC niche (basal striated duct cells, BSD) was examined in SGs of pSS (n=35), incomplete pSS (n=13) (patients with some signs of pSS, but not fulfilling all classification criteria) and non-SS sicca control (n=21) patients. This was correlated with functional and clinical parameters.
Results
Results pSS patient SGs contained significantly more p16+ cells both in the epithelium in general (p<0.01) and in the BSD layer (p<0.001), than non-SS SGs (see figure). Significant correlations were found in pSS patients between p16+ BSD cells and secretion of unstimulated whole saliva, stimulated whole saliva, stimulated parotid saliva, CD45+ infiltrate, ultrasound total score, and ACR-EULAR classification score, but not with ESSDAI and ESSPRI scores. Correlations with total epithelium p16+ cells were weaker. Incomplete pSS patients also had increased numbers of p16+ epithelial and BSD cells. Based on protein and mRNA expression, p21+ appears not to play a significant role in the SG in pSS.
Conclusions
Conclusion These findings suggest SGPC senescence maybe an early feature of primary Sjögren’s syndrome and contribute to defective SG function in pSS but not to systemic disease activity.
ELECTRIC FIELD INDUCED RELEASE AND MEASUREMENT (EFIRM), A NOVEL PLATE-BASED SALIVA ASSAY CAN DISCRIMINATE BETWEEN SJÖGREN SYNDROME AND SICCA PATIENTS
- Charles Strom, United States of America
Abstract
Background and Aims
Sjogren Syndrome (SS) is an autoimmune disorder of the salivary glands and tear ducts. Although SS is rare, the symptoms of dry mouth and dry eyes (SICCA) are common. Since SS patients have increased malignancy risk and SS treatments are being developed, differentiating SS from SICCA will become important. SS patients often have circulating autoantibodies to SSA (~85%) and/or SSB (~65%), but serum testing cannot reliably discriminate between SS and SICCA. We created a saliva test capable of differentiating SS from SICCA patients.
Methods
EFIRM was designed specifically for direct analysis of biomarkers in saliva. We developed assays for total Ig against SSA in saliva. We obtained blinded frozen saliva samples from 33 SS patients and 36 SICCA patients with known serum SSA and SSB values from Seoul National University Hospital.
Results
Five patients with SS had negative serum anti-SSA results but all 5 were positive by EFIRM in saliva. All SICCA patients were also saliva positive for anti-SSA so there no discrimination between SS from SICCA. We then developed specific tests for IgA1 monomer (mIgA1) and IgA1 polymer (pIgA1) using the lectins Erythina Cristigali (mIgA1) and Helix pomatia (pIgA1) respectively against anti-SSA. Cluster analysis using the results of the 3 assays unambiguously discriminated between the 33 SS and 36 SICCA patients and both from 41 unaffected individuals. Patients with SS had a predominance of pIgA1 in contrast to SICCA patients who had a predominance of mIgA1. Unaffected controls had neither.
Conclusions
If confirmed, we created a noninvasive saliva diagnostic for SS.
ASSOCIATION OF BAFF AND CXCL13 PERIPHERAL SOLUBLE LEVELS WITH CLINICAL PARAMETERS IN PRIMARY SJOGREN’S SYNDROME PATIENTS
- Francisco Josue Carrillo-Ballesteros, Mexico
Abstract
Background and Aims
Primary Sjögren’s syndrome (pSS) is an autoimmune disease with focal lymphocytic sialadenitis (FLS) in exocrine glands. In the context of pSS, several cytokines play a fundamental role, including BAFF, a key molecule for B cell survival, maturation, and differentiation, and CXCL13, an essential chemokine for lymphocytes recruitment. The aim was to associate BAFF and CXCL13 soluble levels with clinical parameters in pSS patients.
Methods
Peripheral blood samples were collected from pSS patients (n=25) classified according to 2016 AECG criteria and healthy subjects (HS) (n=32). Moreover, the patients were stratified in non-specific chronic sialadenitis (NSCS), FLS, and those with ectopic germinal centers (GC+) or without them (GC-). Soluble BAFF and CXCL13 levels were determined by ELISA, and disease duration, clinical manifestations and antibodies (RF, ANAs, anti-Ro/SSA, anti-La/SSB, and IgG) were considered as clinical parameters.
Results
BAFF soluble levels in pSS were higher than HS (p=0.0161, 1104.0 vs 830.7 pg/mL), the FLS-GC(-) group showed the highest levels (1257.0 pg/mL). Soluble levels of CXCL13 also were higher pSS than HS (p=0.0026, 116.9 vs 48.97 pg/mL), both groups with FLS (GC+ and GC-) displayed the highest concentrations (113.6 and 126.2 pg/mL). Positive correlations between BAFF and disease duration were found (r=0.4394, p=0.0317), and also with anti-La/SSB (r=0.4201, p=0.0366); besides with CXCL13 and anti-La/SSB (r=0.4506, p=0.0238). CXCL13 levels where high in ANAs(+) patients (p=0.0344, 85.02 vs 149.60 pg/mL).
Conclusions
pSS patients display high BAFF and CXCL13 soluble levels. These molecules may be useful as potential biomarkers for diagnostics and disease severity.
CHRONIC STRESS DRIVES ENDOPLASMIC RETICULUM STRESS AND ACTIVATION OF THE UNFOLDED PROTEIN RESPONSE IN MINOR SALIVARY GLAND CELLS OF PATIENTS WITH PRIMARY SJÖGREN'S SYNDROME.
- Stergios Katsiougiannis, Greece
Abstract
Background and Aims
Compelling evidence suggests that stress plays an important role in autoimmunity. Sjögren's syndrome (SS) is an autoimmune disease in which the main targets of immune injury are specific secretory epithelia, such as salivary glands. Our aim was to investigate the role of chronic stress in triggering endoplasmic reticulum (ER) stress in salivary gland epithelial cells (SGEC) of SS patients and controls.
Methods
Minor salivary gland biopsies were obtained from 6 SS patients and 6 disease controls. Expression of β1-, β2-, α1-adrenoceptors and cAMP were analyzed by Immunofluorescence. ER architecture was evaluated in situ by Transmission Electron Microscopy (TEM). SGEC were treated with epinephrine and levels of ER stress markers CHOP and GRP78/Bip were determined by immunoblotting.
Results
In situ immunofluorescence demonstrated increased expression of β1-, β2- and α1 adrenoceptors in SS tissues compared to controls. Moreover, cAMP levels were higher in SS tissues. TEM analysis revealed ER lumen dilation in SGEC from the SS samples. By mimicking chronic stress in vitro, we demonstrate that epinephrine induces severe ER stress of SGEC, indicated by increased expression of GRP78/Bip and CHOP.
Conclusions
Our data delineate that adrenoceptors are differentially expressed by salivary epithelium in SS. These findings are substantiated by the increased levels of cAMP in SS-SGEC indicating a profound sympathetic stimulation. The dilated ER lumen in SGEC from SS patients confirm the occurrence of ER stress. The significant finding that catecholamines induce severe ER stress in vitro in SGEC under conditions resembling chronic stress suggest a causal relationship between sympathetic tone and ER stress.
IDENTIFICATION OF A SALIVA EXOSOMAL RNA SIGNATURE FOR SJOGREN’S SYNDROME
- Athena Papas, United States of America
Abstract
Background and Aims
To identify a saliva exosomal RNA (exoRNA) based test to help diagnose Sjogren’s.
Methods
A novel long RNA-Seq workflow was developed to selectively enrich and profile human exosomal mRNAs and long non-coding RNAs (lncRNAs) from saliva. We then profiled salivary exoRNA obtained from 7 SS patients and 7 healthy matched controls. Next, we performed differential gene expression analysis and identified an exoRNA signature for SS. Finally, we validated our gene signature in an independent cohort of 7 SS & 11 healthy controls.
Results
RNA-Seq data analysis demonstrated enrichment of human transcriptome, with over 80% of reads mapping to the human transcriptome. At a conservative threshold of 1 RPM (reads per million), we detected over 10,000 mRNAs and approx.1000 lncRNAs. Differential expression analysis of SS vs. healthy control exoRNA identified 438 upregulated genes, including 359 mRNAs and 13 lncRNAs (p<0.05). 198 genes were found to be downregulated in SS, including 175 mRNAs and 3 lncRNAs. Principal component analysis resulted in clear separation of SS patients from healthy controls. Using machine learning algorithms, we identified a 10-gene signature sufficient to separate SS from healthy and validated our gene signature in an independent cohort of SS & healthy samples, with an AUC of 0.9 with SSA+ ( .73 with lip biopsy).
Conclusions
Our novel workflow overcomes oral microbiome sequencing read interference, enabling analysis of salivary exosomal mRNAs and lncRNAs for biomarker discovery. The gene signature identified in this ongoing study could provide a non-invasive molecular means of diagnosing Sjogren’s syndrome and potentially identify the effectiveness of treatments.
REPRODUCIBILITY OF MINOR SALIVARY GLAND BIOPSY REPORTS IN SJÖGREN'S SYNDROME AND ITS CORRELATION WITH DISEASE BIOMARKERS
- Álvaro Vivas, Colombia
Abstract
Background and Aims
Diagnosis of Sjögren's syndrome (SS) can be challenging. Minor salivary gland biopsy (MSGB) is a useful ancillary study. However, different factors make their interpretation difficult. Also, the significance of distinct histopathological findings is unknown. Our objective was to determine the concordance between pathologists and rheumatologists in the interpretation of MSGBs results and the correlation (if any) between MSGB findings and paraclinical parameters.
Methods
This descriptive retrospective study reviewed medical charts from 998 individuals with sicca symptoms in whom a MSGBs was performed. Rheumatologists interpreted biopsy reports from pathologists in order to obtain the interobserver variability. We then performed logistic regression using immunological and histological parameters.
Results
We included 998 patients with sicca symptoms, the median age was 55 years (45-64 years). The majority were females (n=934, 93.6%). Chisholm and Mason's scoring system was the most used scale by pathologists (55.1%). There was a correlation between pathologists and rheumatologists for the diagnosis of SS regarding MSGB (Cohen’s kappa 0.91). In addition to focal lymphocytic infiltrates, we found a strong association between interstitial plasmocytes and SS (OR 24, 95% CI 9.09-64.94, p = 0). The logistic regression evaluating the probability of being diagnosed with SS by a rheumatologist, upon the presence of histological characteristics in the MSGB is shown in Table.
Conclusions
The MSGB is an essential tool for the diagnosis of SS. However, different factors may negatively affect its reproducibility. Histological findings, such as interstitial plasmocytes, may predict the risk of having SS.