Exposure to air pollution as an environmental determinant of how Sjögren's disease is expressed at diagnosis

OBJECTIVES

To analyse how the potential exposure to air pollutants can influence the key components at the time of diagnosis of Sjögren's phenotype (epidemiological profile, sicca symptoms, and systemic disease).

METHODS

For the present study, the following variables were selected for harmonization and refinement: age, sex, country, fulfilment of 2002/2016 criteria items, dry eyes, dry mouth, and overall ESSDAI score. Air pollution indexes per country were defined according to the OECD (1990-2021), including emission data of nitrogen and sulphur oxides (NO/SO), particulate matter (PM2.5 and 1.0), carbon monoxide (CO) and volatile organic compounds (VOC) calculated per unit of GDP, Kg per 1000 USD.

RESULTS

The results of the chi-square tests of independence for each air pollutant with the frequency of dry eyes at diagnosis showed that, except for one, all variables exhibited p-values <0.0001. The most pronounced disparities emerged in the dry eye prevalence among individuals inhabiting countries with the highest NO/SO exposure, a surge of 4.61 percentage points compared to other countries, followed by CO (3.59 points), non-methane (3.32 points), PM2.5 (3.30 points), and PM1.0 (1.60 points) exposures. Concerning dry mouth, individuals residing in countries with worse NO/SO exposures exhibited a heightened frequency of dry mouth by 2.05 percentage points (p<0.0001), followed by non-methane exposure (1.21 percentage points increase, p=0.007). Individuals inhabiting countries with the worst NO/SO, CO, and PM2.5 pollution levels had a higher mean global ESSDAI score than those in lower-risk nations (all p-values <0.0001). When systemic disease was stratified according to DAS into low, moderate, and high systemic activity levels, a heightened proportion of individuals manifesting moderate/severe systemic activity was observed in countries with worse exposures to NO/SO, CO, and PM2.5 pollutant levels.

CONCLUSIONS

For the first time, we suggest that pollution levels could influence how SjD appears at diagnosis in a large international cohort of patients. The most notable relationships were found between symptoms (dryness and general body symptoms) and NO/SO, CO, and PM2.5 levels.

Interferons and systemic lupus erythematosus: Pathogenesis, clinical features, and treatments in interferon-driven disease

Type I interferons (IFNs) have recently received a lot of attention with the elucidation of the pathogenesis of systemic lupus erythematosus (SLE). Type I IFNs are associated with many SLE symptoms and play a role in the pathogenesis of autoimmune diseases that may occur concurrently with SLE, such as Sjögren's syndrome, antiphospholipid syndrome, myositis, scleroderma, and interferonopathy. Type I IFNs could be the link between these diseases. However, direct measurement of type I IFN levels and the IFN gene signature is currently unavailable in clinical practice. This review discusses type I IFN signalling in SLE, investigates the role of type I IFN in the clinical manifestations and symptoms associated with SLE and other IFN-related diseases, and discusses the clinical tests that can be used to diagnose SLE and measure disease activity. In addition, the role of type I IFN-blocking therapies as potential treatments for SLE is discussed.

Lessons from Animal Models in Sjögren's Syndrome

Primary Sjögren's syndrome (pSS) is a connective tissue disease characterized by a wide spectrum of clinical features, extending from a benign glandular disease to an aggressive systemic disorder and/or lymphoma. The pathogenesis of Sjögren's syndrome (SS) is not completely understood, but it is assumed that pathogenesis of SS is multifactorial. The studies based on the animal models of SS provided significant insight in SS disease pathogenesis and management. The aim of this review is to summarize current studies on animal models with primary SS-like symptoms and discuss the impact of these studies on better understanding pathogenesis and management of Sjögren's syndrome. Databases PubMed, Web of Science, Scopus and Cochrane library were searched for summarizing studies on animal models in SS. Available data demonstrate that animal models are highly important for our understanding of SS disease.

Exploiting the role of T cells in the pathogenesis of Sjögren's syndrome for therapeutic treatment

Sjögrens syndrome (SS) is caused by autoantibodies that attack proprioceptive salivary and lacrimal gland tissues. Damage to the glands leads to dry mouth and eyes and affects multiple systems and organs. In severe cases, SS is life-threatening because it can lead to interstitial lung disease, renal insufficiency, and lymphoma. Histological examination of the labial minor salivary glands of patients with SS reveals focal lymphocyte aggregation of T and B cells. More studies have been conducted on the role of B cells in the pathogenesis of SS, whereas the role of T cells has only recently attracted the attention of researchers. This review focusses on the role of various populations of T cells in the pathogenesis of SS and the progress made in research to therapeutically targeting T cells for the treatment of patients with SS.

Qing Zao Fang (QZF) Alleviates the Inflammatory Microenvironment of the Submandibular Gland in Sjögren's Syndrome Based on the PI3K/Akt/HIF-1α/VEGF Signaling Pathway

Sjögren's syndrome (SS) which could lead to a disorder of our immune system is a chronic autoimmune disease characterized by invading exocrine glands such as salivary glands and lacrimal glands and other exocrine glands. Its common symptom is dry mouth and dry eyes, often accompanied by a large number of lymphocyte infiltrations and can involve other organs to cause complex clinical manifestations. In this study, we aimed at investigating the effect of QZF in SS, identifying the molecular mechanism in modulating autoimmune response, and determining the important roles of these factors' function as a modulator in the pathogenesis of SS. The NOD mice were utilized to establish the rats' model of Sjögren's syndrome. After 10 weeks' hydroxychloroquine and QZF in different dose interference, submandibular gland tissue was collected. The therapeutic effect of QZF on SS rats was identified, and the results suggest the comparable potential to hydroxychloroquine. In submandibular gland tissue, interleukin- (IL-) 17 was significantly lower in high-dose QZF than that in SS rats and the focal lymphocytes were highly attenuated. Moreover, we found that PI3K/Akt signals were activated and the downstream HIF-1α/VEGF signals were enhanced in SS rats whose protein expression could be inhibited by QZF treatment. In addition, QZF could modulate autophagy in submandibular gland tissue and then inhibit the inflammation response and therefore facilitate the tissue repair.

Integrative epigenomics in Sjögren´s syndrome reveals novel pathways and a strong interaction between the HLA, autoantibodies and the interferon signature

Primary Sjögren's syndrome (SS) is a systemic autoimmune disease characterized by lymphocytic infiltration and damage of exocrine salivary and lacrimal glands. The etiology of SS is complex with environmental triggers and genetic factors involved. By conducting an integrated multi-omics study, we confirmed a vast coordinated hypomethylation and overexpression effects in IFN-related genes, what is known as the IFN signature. Stratified and conditional analyses suggest a strong interaction between SS-associated HLA genetic variation and the presence of Anti-Ro/SSA autoantibodies in driving the IFN epigenetic signature and determining SS. We report a novel epigenetic signature characterized by increased DNA methylation levels in a large number of genes enriched in pathways such as collagen metabolism and extracellular matrix organization. We identified potential new genetic variants associated with SS that might mediate their risk by altering DNA methylation or gene expression patterns, as well as disease-interacting genetic variants that exhibit regulatory function only in the SS population. Our study sheds new light on the interaction between genetics, autoantibody profiles, DNA methylation and gene expression in SS, and contributes to elucidate the genetic architecture of gene regulation in an autoimmune population.

Metformin as a Treatment Strategy for Sjögren's Syndrome

Sjögren’s syndrome (SS), a chronic inflammatory disease involving the salivary and lacrimal glands, presents symptoms of sicca as well as systemic manifestations such as fatigue and musculoskeletal pain. Only a few treatments have been successful in management of SS; thus treatment of the disease is challenging. Metformin is the first-line agent for type 2 diabetes and has anti-inflammatory potential. Its immunomodulatory capacity is exerted via activation of 5’ adenosine monophosphate-activated protein kinase (AMPK). Metformin inhibits mitochondrial respiratory chain complex I which leads to change in adenosine mono-phosphate (AMP) to adenosine tri-phosphate (ATP) ratio. This results in AMPK activation and causes inhibition of mammalian target of rapamycin (mTOR). mTOR plays an important role in T cell differentiation and mTOR deficient T cells differentiate into regulatory T cells. In this manner, metformin enhances immunoregulatory response in an individual. mTOR is responsible for B cell proliferation and germinal center (GC) differentiation. Thus, reduction of B cell differentiation into antibody-producing plasma cells occurs via downregulation of mTOR. Due to the lack of suggested treatment for SS, metformin has been considered as a treatment strategy and is expected to ameliorate salivary gland function.

Cytokine profiles and clinical characteristics in primary Sjögren´s syndrome patient groups

BACKGROUND

Primary Sjögren's syndrome (pSS) is an autoimmune disease characterized by a lymphocytic infiltrate in salivary glands driving to epithelial damage. The pSS patients present heterogenic clinical and serological characteristics. This heterogenicity could be due to the cytokine microenvironment. Cytokine levels have been analyzed and reported individually, showing controversial results; for that reason, we considered essential to evaluate a cluster of cytokines and relate them with antibody levels and clinical characteristics to find pSS subgroups.

METHODS

Ninety-nine pSS patients, diagnosed by the 2016 ACR/EULAR classification criteria, and 76 control subjects (CS) were included. Cytokine quantification was performed by Multiplex assay. Principal component analysis (PCA) was realized, and the K-mean test was used to identify clusters/groups. Groups were analyzed by the Kruskal-Wallis test and the Bonferroni test.

RESULTS

Higher IFN-γ, IL-17F, IL-21, IL-23, IL-4, and IL-31 levels were observed in pSS patients in comparison with control subjects. PCA analysis showed three groups. The severe group was characterized by higher cytokine concentrations as well as an increase in clinical parameters such as antibody levels, damage index score, and others. The moderate group presented intermediate severity; meanwhile, the mild group presented the lowest severity.

CONCLUSION

Cluster analysis revealed three groups that were different in cytokine levels and clinical parameters in which the mild group was defined by lower severity, the moderate group with intermediate severity, and the severe group with higher severity. This analysis could help subclassify the primary Sjögren syndrome patients for a better understanding of the clinical phenotype that impacts the treatment approach.

Early diagnosis and treatment for Sjögren's syndrome: current challenges, redefined disease stages and future prospects

There are some challenges and unmet needs in the early diagnosis and management of Sjögren's syndrome (SjS) such as prominent glandular dysfunction at diagnosis and long diagnostic delay. Those challenges are partly attributed to the lack of a good knowledge of the early stages of SjS, which is a major obstacle to delivering appropriate care to SjS patients. Findings from both clinical and experimental studies suggest the plausibility of a redefined SjS course consisting of 4 stages, which includes initiation stage, preclinical stage, asymptomatic SjS stage and overt SjS stage. More studies focusing on the pathological processes and changes during the early stages of SjS are needed. To enable early diagnosis and treatment for SjS, more useful biomarkers of the early stages of SjS need to be identified, and individuals at high risk of SjS development need to be identified. Appropriate screening can be performed to facilitate the early diagnosis of SjS among those high-risk individuals.

Can Gut Microbiota Affect Dry Eye Syndrome?

Using metagenomics, continuing evidence has elicited how intestinal microbiota trigger distant autoimmunity. Sjögren's syndrome (SS) is an autoimmune disease that affects the ocular surface, with frequently unmet therapeutic needs requiring new interventions for dry eye management. Current studies also suggest the possible relation of autoimmune dry eye with gut microbiota. Herein, we review the current knowledge of how the gut microbiota interact with the immune system in homeostasis as well as its influence on rheumatic and ocular autoimmune diseases, and compare their characteristics with SS. Both rodent and human studies regarding gut microbiota in SS and environmental dry eye are explored, and the effects of prebiotics and probiotics on dry eye are discussed. Recent clinical studies have commonly observed a correlation between gut dysbiosis and clinical manifestations of SS, while environmental dry eye portrays characteristics in between normal and autoimmune. Moreover, a decrease in both the Firmicutes/Bacteroidetes ratio and genus Faecalibacterium have most commonly been observed in SS subjects. The presumable pathways forming the "gut dysbiosis-ocular surface-lacrimal gland axis" are introduced. This review may provide perspectives into the link between the gut microbiome and dry eye, enhance our understanding of the pathogenesis in autoimmune dry eye, and be useful in the development of future interventions.

Risk of incident autoimmune diseases in patients with thymectomy

OBJECTIVES

The data concerning the association between Tx and ADs remain unclear and are scarce. This study was undertaken to investigate whether people with Tx are more likely to develop ADs, compared to those without Tx.

METHODS

Individuals who received Tx between 2002 and 2015 were identified and matched on age and sex with individuals without Tx. We performed multivariate and stratified analysis using the Kaplan-Meier method and Cox proportional hazards models in order to estimate the association between Tx and the risk of developing ADs.

RESULTS

A total of 2550 thymectomized (Txd) patients and 24,664.941 non-Txd comparison subjects were selected from NHIRD. Tx-MG (myasthenia gravis) as compared with general population (nonTx-nonMG), adjusted hazard ratio (aHR) were higher for incident Addison disease (aHR = 10.40, 95% CI 1.01-107), autoimmune hemolytic anemia (aHR = 21.54, 95% CI 2.06-14.8), Hashmoto thyroiditis (aHR = 5.52, 95% CI 1.34-34.7), ankylosing spondylitis (aHR = 2.73, 95% CI 1.09-6.84), rheumatoid arthritis (aHR = 5.25, 95% CI 1.79-15.47), primary Sjogren syndrome (pSS) (aHR = 3.77, 95% CI 1.30-11.0), and systemic lupus erythemtoasus (aHR = 10.40). Tx-nonMG as compared with general population, aHR were higher for incident autoimmune hemolytic anemia (aHR = 25.50), Hashmoto thyroiditis (aHR = 6.75) and systemic lupus erythematosus (SLE) (aHR = 13.38). NonTx-MG as compared with general population, aHR were higher for incident Hashmoto thyroiditis (aHR = 6.57), pSS (aHR = 4.50), SLE (aHR = 17.29), and systemic vasculitis (aHR = 25.86).

INTERPRETATION

In conclusion, based on a retrospective cohort study throughout Taiwan, patients with Tx have a higher risk of new onset ADs than patients without Tx.

Expression of BAFF and BAFF receptors in primary Sjögren's syndrome patients with ectopic germinal center-like structures

B cell-activating factor (BAFF) is an essential cytokine in primary Sjögren's syndrome (pSS) physiopathology. It has been reported that pSS patients develop germinal center-like (GC-like) structures in their minor salivary glands (MSGs). BAFF, BAFF-R, TACI, and BCMA expression was analyzed in MSGs from 29 subjects (nonspecific chronic sialadenitis and focal lymphocytic sialadenitis with the presence [pSS-GC(+)] or absence [pSS-GC(-)] of GC-like structures). Twenty-four percent of patients showed ectopic GC-like structures and a high focus score [p < 0.001 vs pSS-GC(-)]. BAFF serum levels (sBAFF) were high in pSS patients (p = 0.025 vs healthy subjects). However, the pSS-GC(-) group showed higher sBAFF levels than pSS-GC(+) patients. BAFF and BAFF-R glandular expression levels were higher in pSS-GC(+) patients, without significant differences compared to pSS-GC(-) patients. Soluble levels of BAFF correlated with anti-La/SSB antibodies and disease duration. Our results showed that BAFF could contribute to focal lymphocytic infiltration. The role of BAFF-binding receptors in MSGs is proposed as a mechanism for the possible establishment of ectopic GC-like structures and disease progression in some patients. In conclusion, this study supports previous evidence that considers the active BAFF system role in the pathogenesis of pSS and the need for strong biomarkers in this disease.

Agonist-induced 4-1BB activation prevents the development of Sjӧgren's syndrome-like sialadenitis in non-obese diabetic mice

Activation of costimulatory receptor 4-1BB enhances T helper 1 (Th1) and CD8 T cell responses in protective immunity, and prevents or attenuates several autoimmune diseases by increasing Treg numbers and suppressing Th17 or Th2 effector response. We undertook this study to elucidate the impact of enforced 4-1BB activation on the development of Sjögren's syndrome (SS)-like sialadenitis in non-obese diabetic (NOD) model of this disease. An anti-4-1BB agnostic antibody was intraperitoneally injected to female NOD mice aged 7 weeks, prior to the disease onset that occurs around 10-11 weeks of age, 3 times weekly for 2 weeks, and the mice were analyzed for SS pathologies at age 11 weeks. The salivary flow rate was markedly higher in the anti-4-1BB-treated NOD mice compared to the IgG-treated controls. Anti-4-1BB treatment significantly reduced the leukocyte infiltration of the submandibular glands (SMGs) and the levels of serum antinuclear antibodies. Flow cytometric analysis showed that the percentages of CD4 T cells, Th17 cells and plasmacytoid dendritic cells among SMG leukocytes were markedly reduced by anti-4-1BB treatment, in conjunction with a reduction in SMG IL-23p19 mRNA levels and serum IL-17 concentrations. Although the proportion of Tregs and IL-10 mRNA levels in SMGs were not altered by 4-1BB activation, IL-10 mRNA levels in salivary gland-draining lymph nodes and serum IL-10 concentrations were both markedly increased. While anti-4-1BB treatment did not affect the amount of Th1 cells and IFNγ mRNA in the SMGs, it increased these measurables in salivary gland-draining lymph nodes. Hence, agonistic activation of 4-1BB impedes the development of SS-like sialadenitis and hyposalivation.

Dual function of miR-1248 links interferon induction and calcium signaling defects in Sjögren's syndrome

BACKGROUND

Sjögren's syndrome (SS) is one of the most common autoimmune disorders leading to exocrine gland dysfunction. Both immune-dependent processes - like Type I Interferon (IFN) signaling and immune-independent processes - such as calcium signaling in epithelial cells - contribute to disease pathophysiology. However, a mechanistic link between these processes has not been demonstrated.

METHODS

Primary human salivary gland cells were used to evaluate the differential expression of miRNAs with smRNA-seq in primary epithelial cells culture and digital PCR was conducted in SS human salivary glands (SG) biopsies to verify the results. With siRNA screening and pull-down assays to establish the role of miRNA in IFN activation.

FINDINGS

Activation of IFN-β by miR-1248 is through the direct association with both RIG-I and AGO2. Further functional studies establish a unique dual functional role of miR-1248 in phSG cells: i) activation of the RIG-I pathway by acting as ligand of this sensor leading to IFN production and ii) regulation of the expression of mRNAs through the canonical microRNA function. Importantly, ITPR3, a key component of calcium signaling in epithelial cells, that has previously shown to be downregulated in SS SG, was directly targeted and downregulated by miR-1248, inducing the same functional calcium signaling changes as observed in SS SGs.

INTERPRETATION

Identification of the first endogenous mammalian microRNA that binds to RIG-I inducing IFN production but also demonstrate a novel pathophysiological underlying mechanism in which miR-1248 overexpression links two major pathways associated with SS, namely activation of IFN production with modulation of calcium signaling. Together, these findings suggest a unifying hypothesis for the immune-independent and -dependent processes contributing to the pathogenesis of SS. FUND: This research was supported by the Intramural Research Program of the National Institutes of Health (NIH), National Institute of Dental and Craniofacial Research (NIDCR).

The role of Epstein-Barr virus infection in primary Sjögren's syndrome

PURPOSE OF REVIEW

The purpose of this article is to draw attention to the role of Epstein-Barr virus (EBV) virus in the pathogenesis of the primary Sjögren's syndrome. The article introduces the problem of consequences of EBV acute infection, and its reactivation, in association with the immune response modulation by the virus and with an increased risk of developing systemic autoimmune diseases and EBV-associated cancers.

RECENT FINDINGS

The knowledge about the mechanisms by which the virus may stay for years in a latent phase, unrecognized by the host response immune cells is constantly expanding. There are several mechanisms and theories about EBV influence on the autoimmune process in Sjogren's syndrome (pSS), including the similarity (molecular mimicry) between viral EBNA-2 protein and Ro-60 antigen or EBER-1 and EBER-2 viral proteins and La antigen.

SUMMARY

The influence of EBV infection on the development and course of pSS has been proven. It has also been established that both EBV and pSS result in the increased risk of tumor (especially lymphoma) development. In the light of these findings, new ways to manage EBV infections are being sought. Optimal methods for assessing EBV infection status are being devised. Research also aims at finding therapies, which target EBV through the inhibition of the autoimmune process and of viral activity. The present article is an attempt to discuss the most important phenomena and elements linking EBV infection to the primary Sjögren's syndrome.

Neuro-Sjögren: Peripheral Neuropathy With Limb Weakness in Sjögren's Syndrome

Objective: Sjögren's syndrome is a heterogeneous inflammatory disorder frequently involving peripheral nerves with a wide spectrum of sensory modalities and distribution patterns. The objective of this cross-sectional study was to determine characteristics of Sjögren's syndrome as a cause for severe neuropathy with limb weakness. Methods: One hundred and eighty four patients with polyneuropathy associated with limb weakness underwent routine diagnostics including investigations for Sjögren's syndrome. Forty-four patients with Sjögren's syndrome (ACR-EULAR classification criteria) and severe neuropathy were identified. Results: Sjögren's syndrome was found at a median age of 63 years and the gender distribution showed a balanced female-male ratio of 1:1. Anti-SSA(Ro) antibodies were detected in 48% while seronegative patients were diagnosed with Sjögren's syndrome based on sialadenitis on minor salivary gland biopsy with a focus score ≥1. The majority of patients (93%) were diagnosed with Sjögren's syndrome after neurological symptoms appeared. Limbs were symmetrically involved in 84% of patients (57% tetraparesis, 27% paraparesis). Sensory function was not affected in 11% of patients indicating that Sjögren's syndrome associated neuropathy can present as a pure motor syndrome. Electrophysiological measurements did not reveal pathognomonic findings (23% demyelinating pattern, 36% axonal pattern, 41% both demyelinating and axonal damage signs). More than half of our patients fulfilled the European Federation of Neurological Societies (EFNS) diagnostic criteria for CIDP indicating that distinction between Neuro-Sjögren and other causes of neuropathy such as CIDP is challenging. Interpretation: Our findings show that severe neuropathy with limb weakness is often associated with Sjögren's syndrome. This is of great importance in identifying and understanding the causes of immune mediated polyneuropathy.

Overexpression of Smac is associated with the development of primary Sjogren's syndrome

BACKGROUND

Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease characterized by keratoconjunctivitis sicca, xerostomia, and extraglandular abnormalities. The precise etiology remains unclear. Previous studies have revealed that the apoptosis played an important role in the pSS. Herein, we investigated the expression and effect of second mitochondria-derived activator of caspase (Smac) in patients with pSS and associated the expression with clinicopathological parameters.

METHODS

Smac expression was checked in labial salivary glands of surgical specimens from cases of pSS using immunohistochemistry, reverse transcription-quantitative PCR, and Western blot. The results of immunohistochemistry were analyzed for clinicopathological parameters. In addition, the content of Smac in cytoplasm and mitochondria were examined.

RESULTS

The mRNA of Smac, the content of Smac in cytoplasm, the Smac protein in the pSS patients increased significantly compared with the healthy controls (p < 0.05). The content of Smac in mitochondria decreased significantly compared with the healthy controls (p < 0.05). The integral optical density of Smac protein levels were positively correlated with IgG (r = 0.7435, p < 0.05) and erythrocyte sedimentation rate (ESR) (r = 0.7925, p < 0.05).

CONCLUSION

Smac plays an important role in the development of pSS.

Angiogenic T cells in primary Sjögren's syndrome: a double-edged sword?

OBJECTIVES

The mechanisms underlying increased cardiovascular risk in primary Sjögren's syndrome (pSS) remain unclear. Since the recently discovered angiogenic T cells (Tang) may participate in endothelial repair by cooperating with endothelial progenitor cells (EPC), we aimed to quantify and characterise Tang in the peripheral blood and minor salivary glands (MSG) of pSS patients.

METHODS

Tang (CD3+CD31+CXCR4+) and EPC (CD34+CD133+VEGFR-2+) were quantified by flow cytometry in peripheral blood samples from 36 pSS patients and 20 healthy donors. Tang subsets were assessed on the basis of CD4, CD8 and CD28 expression. Labial MSG sections from 10 pSS patients and 12 non-pSS sicca syndrome controls were subjected to immunofluorescence staining to investigate the presence of Tang and the expression of the CXCR4-ligand stromal cell-derived factor-1 (SDF-1)/CXCL12.

RESULTS

Circulating Tang cells were expanded and directly correlated to EPC in pSS. Both Tang and EPC directly correlated with disease activity as calculated with the EULAR Sjögren's syndrome disease activity index (ESSDAI). In pSS, the majority of Tang cells were CD4-CD8- double negative (DN) and lacked CD28 revealing a senescent phenotype. A subset of CD4+, CD8+ and DN Tang cells produced interleukin-17. Immunohistology revealed the exclusive presence of periductal and perivascular infiltrating Tang cells along with increased SDF-1/CXCL12 expression in pSS MSG compared to non-pSS sicca syndrome controls.

CONCLUSIONS

In pSS, Tang cells are expanded in peripheral blood and infiltrate MSG. Tang may be novel actors in pSS-related endothelial dysfunction and glandular neo-angiogenesis and inflammation.

Type I interferon signature in Sjögren's syndrome: pathophysiological and clinical implications

Type I interferons (IFN) have long been recognised as mediators of innate immune defense mechanisms against viral threats. Robust evidence over the last 15 years revealed their significant role in the pathogenesis of systemic autoimmune diseases, including systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS). Despite the progress, methods of detection, initial triggers, biological functions and clinical associations in the setting of autoimmunity remain to be fully clarified. As therapeutic options for SS are currently limited, neutralising specific targets of the type I IFN pathway seems a promising option. In this review we summarise the current evidence regarding the role of type I IFN in SS.

Oral microbial flora of patients with Sicca syndrome

Primary sicca syndrome (pSS) is a systemic autoimmune disease. However, its exact etiology and pathogenesis remain elusive. Various infectious factors have been identified to be closely associated with the occurrence and development of PSS. The present study aimed to assess the composition of the oral microbial flora of patients with pSS in China in order to provide guidance for treatment. The microbial flora of nine patients with pSS and five healthy controls from East China was evaluated in saliva samples using high‑throughput sequencing. A high microbial diversity was detected in the pSS and control groups, with bacteroidetes, firmicutes and proteobacteria constituting the largest phyla in the two groups. Compared with the control group, bacteroidetes and actinobacteria were significantly more abundant in the pSS group, whereas proteobacteria were significantly less abundant. However, no significant differences in bacterial richness and diversity were observed between the two groups. According to a Kyoto Encyclopedia of Genes and Genomes linear discriminant analysis, genes regulating cell apoptosis and the immune and digestive systems were significantly upregulated in the pSS group compared with those in the control group. In conclusion, the present study provided basic data on the flora of the oral cavity in patients with pSS from East China and may serve as a reference for the treatment of this condition.

Dysregulated Marginal Zone B Cell Compartment in a Mouse Model of Sjögren's Syndrome with Ocular Inflammation

The risk of developing lymphoma in patients with Sjögren’s syndrome (SS) is 44 times higher than in the normal population with the most common lymphomas derived from marginal zone B (MZB) cells. Current understanding of the role of MZB cells in SS is primarily based on salivary gland pathology, while their contextual association with lacrimal glands and ocular manifestations largely remains unknown. We examined this possibility using a SS mouse model (thrombospondin-1 deficient (TSP1^−/−)) with well-characterized ocular disease. We determined the frequency, localization, and cytokine profiles of MZB cells and their association with an antibody response in TSP1^−/− mice treated with a TSP-derived peptide. A significantly increased frequency of MZB cells was detected in the spleens and lacrimal glands of TSP1^−/− mice in comparison to wild-type tissues as detected by immunostaining. An altered cytokine profile of TSP1^−/− MZB cells was supportive of T helper 17 (Th17)-related pathogenesis. A significantly reduced antibody response and the splenic MZB compartment against an eye-derived antigen were noted in TSP-derived peptide-treated mice. These changes correspond with the previously reported ability of the peptide to ameliorate SS-related ocular manifestations. Collectively, our results demonstrate dysregulation of MZB cells in TSP1^−/− mice and highlight their role in the context of SS-related chronic ocular surface disease.

PBC and related extrahepatic diseases

Patients with PBC have at least 60% of probability to have an autoimmune extrahepatic condition. The pathogenesis of these conditions includes a common mechanism involving both innate and adaptive immune responses targeting cholangiocytes and different extrahepatic tissues. The recent EASL guidelines recommend the management of these conditions, although detailed practical treatments have not been indicated. Autoimmune extrahepatic conditions may include: rheumatologic, endocrine, pulmonary, gastrointestinal, dermatologic diseases. This review aims to focus the most important extrahepatic autoimmune conditions associated to PBC with practical recommendation regarding diagnostic approach and management.

Ophthalmological Aspects in Allogenic Bone Marrow Transplantation: Sjögren-Like Syndrome in Graft-Versus-Host Disease

PURPOSE

A major complication of allogenic bone marrow transplantation (BMT) is graft-versus-host disease (GVHD), characterized principally by involvement of the eyes, producing a Sjögren-like syndrome (SLS). This study assessed the predictive role of the eye involvement in the onset of GVHD.

METHODS

Thirty-five patients transplanted for hematological malignancies were routinely examined for ocular manifestation of dry eye. Examination includes the Schirmer I test, break-up time, Lissamine Green staining, fluorescein test, lactoferrin test and impression cytology. A threshold was established for quantitative analysis of SLS.

RESULTS

Fifteen of 35 patients (40%) developed SLS during long-term follow-up. Ten of these (77%) developed acute or chronic GVHD.

CONCLUSIONS

The possible etiology of SLS includes three factors: total body irradiation, ocular toxicity of chemotherapy and GVHD. A correlation was found between poor-prognosis GVHD and the occurrence of SLS.

Potential Role of Free Fatty Acids in the Pathogenesis of Periodontitis and Primary Sjögren's Syndrome

Clinical studies have shown that metabolic disorders such as type 2 diabetes and dyslipidemia are associated with increased risk of oral-related diseases, such as periodontitis and Sjögren’s syndrome. Although changes in the immune system are critical in both of these metabolic disorders and oral-related diseases, the mechanism underlying the interaction between these diseases remains largely unknown. Obesity and type 2 diabetes are known to be associated with higher concentrations of free fatty acids in blood. Among free fatty acids, saturated fatty acids such as palmitic acid have been demonstrated to induce inflammatory responses mainly via the innate immune systems, and to be involved in the pathogenesis of type 2 diabetes in tissues such as adipose tissue, liver, pancreas, and skeletal muscle. Here, we highlight recent advances in evidence for the potential involvement of palmitic acid in the pathogenesis of periodontitis and Sjögren’s syndrome, and discuss the possibility that improvement of the lipid profile could be a new strategy for the treatment of these diseases.

Compact Bone-Derived Multipotent Mesenchymal Stromal Cells (MSCs) for the Treatment of Sjogren's-like Disease in NOD Mice

Compact bone (cortical or dense bone) is among the organs that contain multipotent mesenchymal stromal cells (MSCs). Unlike bone marrow plugs where MSCs were initially isolated, compact bone has minimal (amount of) hematopoietic cells and thus facilitates the MSCs isolation process. In vitro, MSCs from compact bone show multipotency and differentiation into mesenchymal tissues such as bone, adipose, and cartilage, under certain conditions. MSCs therapy has been promising in preclinical and clinical studies against autoimmune diseases. Not only can MSCs replace the lost tissue through their regenerative properties, but they can also control the autoimmune attacks by immunoregulatory cytokines. This protocol describes the use of compact bone-derived MSCs to preserve salivary function (saliva flow/output) in the NOD (nonobese diabetic) mouse model affected with Sjogren's-like disease.

Exploring BAFF: its expression, receptors and contribution to the immunopathogenesis of Sjögren's syndrome

SS is an autoimmune condition characterized by exocrine gland destruction, autoantibody production, immune complex deposition and systemic complications associated with lymphocytic infiltration of many organs. Genetic, environmental and viral factors play a role in disease aetiology, however, the exact mechanisms driving the immunopathogenesis of SS remain uncertain. Here we discuss a role for B cell activating factor (BAFF), whereby B cell hyperactivity and increased BAFF secretion observed in patients and animal models of the disease can be explained by the altered expression of cell-specific BAFF/BAFF receptor (BAFF-R) variants in several immune cell types. Understanding the role of BAFF/BAFF-R heterogeneity in SS pathogenesis could help to facilitate new treatment strategies for patients.

Autoantibodies recognizing the 27 carboxy-terminal amino acids of calpastatin are associated with secondary Sjögren syndrome in systemic lupus erythematosus

The objective of this study was to determine in systemic lupus erythematosus (SLE) the prevalence and clinical significance of anticalpastatin antibodies (ACAST), an autoantibody population previously detected in sera from patients with various connective tissue diseases. Eighty-four patients with SLE (mean age: 30 years at diagnosis, females 77) that fulfilled ACR criteria were included in the study retrospectively. Several clinical and biological data were collected. ACAST were detected by a solid-phase enzyme linked immunosorbent assay (ELISA) using as antigen a synthetic peptide corresponding to the 27 C-terminal amino acids of calpastatin (CAST-C27). The prevalence of ACAST-C27 was 13% (11/84) in SLE patients. No correlation was found between the presence of ACAST-C27 and clinical manifestations such as thrombosis and vasculitis. Furthermore, no correlation was observed with the presence of antiphospholipid antibodies (APL). However, we found a statistically significant association between the presence of ACAST-C27 and that of secondary Sjögren syndrome ( P = 0.01). The conclusion is ACAST-C27 are not associated with thrombosis in SLE patients. The association observed between ACAST-C27 and secondary Sjögren syndrome suggests that ACAST-C27 might be useful in discriminating a clinical subgroup of SLE patients.

Secondary Sjogren's Syndrome in 83 Patients With Rheumatoid Arthritis

Sjogren syndrome (SS) can occur alone, primary Sjogren syndrome, or in association with other rheumatic diseases, secondary Sjogren syndrome (sSS), such as Rheumatoid arthritis (RA). The occurrence of Sjogren syndrome with RA makes it course worse and increases high morbidity and mortality of RA. In this exploratory study we aim to determine the prevalence of sSS (diagnosed based on the revised version of American-European consensus Group Classification Criteria: AUCG-criteria), sicca symptoms (dry eye, dry mouth), positive autoantibody tests (Anti RO or Anti-LA antibodies), UWSFR (Unstimulated Whole Salivary Flow Rate), Schirmer and Lissamine test. In this cross-sectional study, eighty three consecutive RA patients (according to American College of Rheumatology criteria 1987) who were visited at rheumatology clinic of Razi General Hospital located in the north of Iran entered into our study. Our exclusion criteria was a positive history of past head and neck radiation treatment, Hepatitis C infection, acquired immunodeficiency disease (AIDS), pre-existing lymphoma, sarcoidosis, graft versus host disease, use of anticholinergic drugs (including neuroleptics, antidepressants, antihypertensive and parasympatholytics). They examined with UWSFR by a rheumatologist and with Schirmer test and Lissamine test by an ophthalmologist. Participants were 90.4% female with the mean age 48.3±13 years. Duration of RA was in 36.1% less than 5 years, in 22.9% 5-10 years, in 12.1% 11-15 years and in 28.9% more than 15 years. Our results demonstrated that the prevalence of sSS was 5.9% (CI:0.6%-10.5%). Number of 27.7% of RA patients positively responded to at least one question about sicca symptoms. Among objective tests, only Positive UWSFR and Lissamine test were significantly more common in RA patients with sSS in comparison to ones without sSS (P<0.001, P=0.01 respectively). In RA patients, we found a linear trend between sicca symptoms and aging (P=0.02). In patients with sicca symptoms, among tests that used for assessing decrease in saliva or tear production, only USWFR significantly more common (P=0.01).

IN CONCLUSION

In RA population in North of Iran prevalence of sSS was less than 10%. In them, a significant linear trend existed between aging and sicca symptoms. Among objective tests of AUCG-criteria (except for lip biopsy that was not performed in the current study) only UWSFR and Lissamine test were significantly more common in patients with sSS in comparison ones without it.

One year in review 2016: Sjögren's syndrome

Sjögren's syndrome (SS) is a complex heterogeneous disease charactered by a broad spectrum of clinical and serological manifestations, including non-Hodgkin's lymphoma (NHL). Last year, 2015, was an exciting year for research into SS with novel insights into disease pathogenesis, clinical aspects and long-term outcomes. In addition, the use of biologic therapy in SS is rapidly expanding, with new evidence emerging regarding potential therapeutic targets. In this article, we will provide an overview of the recent literature on the pathogenesis, clinical features and novel treatments of SS.

[Extrahepatic manifestations of HCV infection]

Extrahepatic manifestations of hepatitis C virus infection (HCV) are very common. The most common of these is mixed cryoglobulinaemia. Anti-HCV antibodies and viral ribonucleic acid, HCV RNA, can be found in the cryoprecipitates, together with the rheumatoid factor. Cryoglobulins consist of a complex of immunoglobulins that in vitro precipitate upon the cooling bellow the human body temperature. Vasculitis is caused by the deposition of such immune complexes in the small blood vessels. A link with the HCV infection is considered to be established with membranoproliferative glomerulonephritis, leukocytoclastic vasculitis, lymphoproliferative disorders (in particular B cell lymphoma), Sjögren and sicca syndrome, lichen planus, porfyria cutanea tarda and diabetes mellitus. Very probable is the relationship of chronic HCV infection and thyroid disease, arthralgias, otherwise unexplained fatigue and autoimmune hepatitis.Key words: direct acting antivirals - extrahepatic manifestations - chronic hepatitis C - mixed cryoglobulinaemia.

[Pulmonary involvement in connective tissue disease]

The connective tissue diseases are a variable group of autoimmune mediated disorders characterized by multiorgan damage. Pulmonary complications are common, usually occur after the onset of joint symptoms, but can also be initially presenting complaint. The respiratory system may be involved in all its component: airways, vessels, parenchyma, pleura and respiratory muscles. Lung involvement is an increasing cause of morbidity and mortality in the connective tissue diseases. Clinical course is highly variable - can range from mild to rapidly progressive, some processes are reversible, while others are irreversible. Thus, the identification of reversible disease , and separately progressive disease, are important clinical issues. The frequency, clinical presentation, prognosis and responce to therapy are different, depending on the pattern of involvement as well as on specyfic diagnostic method used to identify it. High- resolution computed tompography plays an important role in identifying patients with respiratory involvement. Pulmonary function tests are a sensitive tool detecting interstitial lung disease. In this article, pulmonary lung involvement accompanying most frequently apperaing connective tissue diseases - rheumatoid arthritis, systemic sclerosis, lupus erythematosus, polymyositis/dermatomyositis, Sjögrens syndrome and mixed connective tissue disaese are reviewed.

TSP-1 Deficiency Alters Ocular Microbiota: Implications for Sjögren's Syndrome Pathogenesis

PURPOSE

The potential role of commensals as triggering factors that promote inflammation in dry eye disease has not been explored. The objective of this study was to evaluate whether ocular microbiota changes with the onset of dry eye disease in thrombospondin-1-deficient (TSP-1(-/-)) mice, a strain that develops Sjögren's syndrome-like disease.

METHODS

Conjunctival swabs were collected from TSP-1(-/-) and C57BL/6 mice and analyzed for bacterial presence. Opsonophagocytosis of the bacterial conjunctival isolates derived from the aged TSP-1(-/-) mice by neutrophils derived from either TSP-1(-/-) or C57BL/6 bone marrow was evaluated. The bactericidal activities of TSP-1-derived peptide were examined.

RESULTS

We found that in TSP-1(-/-) mice, the conjunctival colonization with Staphylococcus aureus and coagulase negative staphylococci sp (CNS) species was significantly increased with aging and preceded that of the wild-type C57BL/6 control mice. This correlated with increased neutrophil infiltration into the conjunctiva of the TSP-1(-/-) mice, suggesting that TSP-1 plays a significant role in regulating immunity to commensals. Accordingly, the TSP-1(-/-) PMNs opsonophagocytozed the ocular commensals less efficiently than the TSP-1-sufficient neutrophils. Furthermore, a TSP-1-derived peptide, 4N1K, exhibited significant antimicrobial activity when compared to a control peptide against commensal sp.

CONCLUSION

These studies illustrate that alterations in the commensal frequency occur in the early stages of development of Sjögren's-like pathology and suggest that interventions that limit commensal outgrowth such as the use of TSP-1-derived peptides could be used for treatment during the early stages of the disease to reduce the commensal burden and ensuing inflammation.

Pleural Effusion In A Patient With Primary Sjögren's Syndrome Successfully Treated With Corticosteroids

Sjögren's syndrome is a systemic autoimmune disorder characterized by salivary insufficiency and lymphocytic infiltration of the exocrine glands. Bronchiolitis and bronchiectasis are common airway manifestations but interstitial pneumonitis, and lymphocytic interstitial pneumonitis may also occur. It rarely presents with pleuritis. We report a woman with primary Sjögren's syndrome who developed pleuritis with moderately large effusions and antibody levels for SS-A and SS-B in the serum without evidence of infection, malignancy or other collagen diseases. After the initial treatment, daily administration of 20 mg of oral prednisone has effectively controlled the serious manifestations of the disease with minimal side effects.

Relationship between disease characteristics and orofacial manifestations in systemic sclerosis: Canadian Systemic Sclerosis Oral Health Study III

OBJECTIVE

Systemic sclerosis (SSc; scleroderma) is associated with decreased saliva production and interincisal distance, more missing teeth, and periodontal disease. We undertook this study to determine the clinical correlates of SSc with these oral abnormalities.

METHODS

Subjects were recruited from the Canadian Scleroderma Research Group cohort. Detailed dental and clinical examinations were performed according to standardized protocols. Associations between dental abnormalities and selected clinical and serologic manifestations of SSc were examined.

RESULTS

One hundred sixty-three SSc subjects were included: 90% women, mean ± SD age 56 ± 11 years, mean ± SD disease duration 14 ± 8 years, 72% with limited cutaneous disease, and 28% with diffuse cutaneous disease. Decreased saliva production was associated with Sjögren's syndrome-related autoantibodies (β = -43.32; 95% confidence interval [95% CI] -80.89, -5.75), but not with disease severity (β = -2.51; 95% CI -8.75, 3.73). Decreased interincisal distance was related to disease severity (β = -1.02; 95% CI -1.63, -0.42) and the modified Rodnan skin thickness score (β = -0.38; 95% CI -0.53, -0.23). The number of missing teeth was associated with decreased saliva production (relative risk [RR] 0.97; 95% CI 0.94, 0.99), worse hand function (RR 1.52; 95% CI 1.13, 2.02), and the presence of gastroesophageal reflux disease (GERD; RR 1.68 [95% CI 1.14, 2.46]). No clinical or serologic variables were correlated with periodontal disease.

CONCLUSION

In SSc, diminished interincisal distance is related to overall disease severity. Decreased saliva production is related to concomitant Sjögren's syndrome antibodies. Tooth loss is associated with poor upper extremity function, GERD, and decreased saliva. The etiology of excess periodontal disease is likely multifactorial and remains unclear.

Systemic sclerosis sine scleroderma and limited cutaneous systemic sclerosis: similarities and differences

OBJECTIVES

To compare a cohort of patients with systemic sclerosis sine scleroderma (ssSSc) vs. patients with limited cutaneous systemic sclerosis (lcSSc).

METHODS

Forty-five patients with ssSSc and 186 patients with lcSSc were investigated. Demographic, clinical and immunologic features and survival were compared.

RESULTS

There were no significant differences between ssSSc and lcSSc in gender, age at onset and interval between onset and diagnosis. ssSSc patients fulfilled the ACR criteria for SSc less than lcSSc patients (13%/77%, p<0.0001). There were no significant differences in articular involvement, myopathy, tendon friction rubs and gastrointestinal, pulmonary, cardiac and renal involvements. There was a trend to higher prevalence of pulmonary arterial hypertension (PAH) in ssSSc patients (29%/19%) but not reach significant difference. The prevalence of antinuclear and anticentromere antibodies and slow capilaroscopic pattern was similar. Sicca syndrome (13%/30%; p=0.024), digital ulcers (16%/50%; p<0.0001), calcinosis (11%/26%; p=0.047) and acroosteolysis (0% /10%; p=0.028) were more frequently in lcSSc. Survival at 5, 10, and 15 yr was not different in ssSSc and lcSSc patients (100%/98%, 100%/98%, and 92%/89%, respectively).

CONCLUSIONS

ssSSc and lcSSc patients share demographic, clinical and immunologic features. Survival is also similar in both groups. Differences are mainly due to peripheral vascular manifestations. However, despite great similarities, we believe that ssSSc patients should be considered as a different subset in order to avoid misdiagnosis. ssSSc patients should be truly differentiated from early SSc using sensitive and specific studies looking for any asymptomatic organ involvement.

Atypical presentation of systemic lupus erythematosus: parotitis and secondary Sjogren's syndrome. Case report

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by auto antibodies directed against self-antigens, immune complex formation and immune deregulations and may affect joints, skin, kidneys, heart, lungs, nervous system, and immune system. The onset can be variable and the symptoms can occur for many years. Parotitis as the initial manifestation of systemic lupus erythematosus (SLE) is a rare condition and can be associated with Sjogren's syndrome. In this article we present the case of a young patient who was diagnosed with Sjogren's syndrome retrospectively, after she met the criteria for SLE.

A case of dermatomyositis with secondary Sjögren's Syndrome-diagnosis with follow-up study of technetium-99m pyrophosphate scintigraphy

PURPOSE

To report a case of dermatomyositis (DM) with secondary Sjögren's syndrome (SS) and propose the clinical application of technetium-99m pyrophosphate ((99m)Tc-PYP) scan.

CASE REPORT

A 50-year-old woman had progressive proximal muscle weakness of bilateral thighs, myalgia, tea-colored urine, and exercise intolerance for 6 months. Physical examination showed malar rash, V-sign, periungual erythema, and mechanic hands. Neurological assessment showed symmetric pelvic-girdle weakness, myopathic face, waddling gait, but preserved deep tendon reflex and sensory functions. DM was diagnosed on the basis of typical rashes and serum creatinine kinase elevation (7397 IU/L). Aside from myopathic symptoms, dry eye and mouth were reported. Thorough autoantibody searches showed positive anti-SSA/Ro antibody (198 U/ml). Both Schirmer's test and sialoscintigraphy were positive, leading secondary SS as diagnosis. Initial (99m)Tc-PYP scan revealed increased radiouptake in the muscles of bilateral thighs, compatible with clinical assessment. Followup scan three months later shows abnormal but attenuated radiouptake at bilateral thighs, in the presence of nearly-complete clinical recovery.

CONCLUSION

DM with secondary SS in adult is a unique disease entity, with predominantly myopathic symptoms and satisfactory therapeutic response as its characteristics. Our serial muscle imaging studies suggest that (99m)Tc-PYP scan is at once anatomically-specific and persistently-sensitive to microstructural damages within inflammatory muscles, enabling clinician to monitor disease activity and therapeutic response.

Miliary sarcoidosis with secondary Sjogren's syndrome

We report a case of miliary sarcoidosis with secondary Sjogren's in a 45-year-old male who presented with symptoms of sicca syndrome in the form of dryness of eyes and mouth with parotid swelling. Computed tomography thorax showed mediastinal and hilar lymphadenopathy, bilateral miliary opacities in lung parenchyma. Whole body FDG PET/CT showed involvement of both parotids, liver, diffuse uptake in lungs, mediastinal and retroperitoneal lymph nodes. Patient is on treatment with prednisolone and has responded well.

Immunization with 60 kD Ro peptide produces different stages of preclinical autoimmunity in a Sjögren's syndrome model among multiple strains of inbred mice

Sjögren's syndrome is a chronic illness manifested characteristically by immune injury to the salivary and lacrimal glands, resulting in dry mouth/eyes. Anti-Ro [Sjögren's syndrome antigen A (SSA)] and anti-La [Sjögren's syndrome antigen B (SSB)] autoantibodies are found frequently in Sjögren's subjects as well as in individuals who will go on to develop the disease. Immunization of BALB/c mice with Ro60 peptides results in epitope spreading with anti-Ro and anti-La along with lymphocyte infiltration of salivary glands similar to human Sjögren's. In addition, these animals have poor salivary function/low saliva volume. In this study, we examined whether Ro-peptide immunization produces a Sjögren's-like illness in other strains of mice. BALB/c, DBA-2, PL/J, SJL/J and C57BL/6 mice were immunized with Ro60 peptide-274. Sera from these mice were studied by immunoblot and enzyme-linked immunosorbent assay for autoantibodies. Timed salivary flow was determined after pharmacological stimulation, and salivary glands were examined pathologically. We found that SJL/J mice had no immune response to the peptide from Ro60, while C57BL/6 mice produced antibodies that bound the peptide but had no epitope spreading. PL/J mice had epitope spreading to other structures of Ro60 as well as to La, but like C57BL/6 and SJL/J had no salivary gland lymphocytic infiltration and no decrement of salivary function. DBA-2 and BALB/c mice had infiltration but only BALB/c had decreased salivary function. The immunological processes leading to a Sjögren's-like illness after Ro-peptide immunization were interrupted in a stepwise fashion in these differing mice strains. These data suggest that this is a model of preclinical disease with genetic control for epitope spreading, lymphocytic infiltration and glandular dysfunction.

Primary Sjögren syndrome presenting with hemolytic anemia and pure red cell aplasia following delivery due to Coombs-negative autoimmune hemolytic anemia and hemophagocytosis

A 36-year-old woman presented with hemolytic anemia without a reticulocyte response 38 days after delivery. A marked reduction in erythroid cells and an increase in macrophages with active hemophagocytosis were noted in the bone marrow. While conventional Coombs' tests were negative, the level of red blood cell (RBC)-bound immunoglobulin G (IgG) was increased. The patient was diagnosed with primary Sjögren syndrome (pSS) based on her symptoms, positive anti-SS-A antibodies, Coombs-negative autoimmune hemolytic anemia and pure red cell aplasia associated with RBC-bound IgG and hemophagocytosis. The unique presentation was considered to be a consequence of immunological derangement associated with pSS, pregnancy and delivery.

Local administration of soluble CD40:Fc to the salivary glands of non-obese diabetic mice does not ameliorate autoimmune inflammation

Objective

CD40–CD154 (CD40 ligand) interaction in the co-stimulatory pathway is involved in many (auto)immune processes and both molecules are upregulated in salivary glands of Sjögren’s syndrome (SS) patients. Interference within the CD40 pathway has ameliorated (auto)inflammation in a number of disease models. To test the potential role of the CD40 pathway in loss of gland function and inflammation in SS, an inhibitor of CD40-CD154 interaction was overexpressed in the salivary glands (SGs) of a spontaneous murine model of SS; the Non-Obese Diabetic (NOD) mouse.

Materials and Methods

At different disease stages an adeno associated viral vector encoding CD40 coupled to a human Fc domain (CD40:Fc) was injected locally into the SGs of NOD mice. Delivery was confirmed by PCR. The overall effect on local inflammation was determined by assessment of the focus score (FS), quantification of infiltrating cell types, immunoglobulin levels, and microarray analysis. The effect on SG function was determined by measuring stimulated salivary flow.

Results

CD40:Fc was stably expressed in the SG of NOD mice, and the protein was secreted into the blood stream. Microarray analysis revealed that expression of CD40:Fc affected the expression of many genes involved in regulation of the immune response. However, FS, infiltrating cell types, immunoglobulin levels, and salivary gland output were similar for treated and control mice.

Discussion

Although endogenous CD40 is expressed in SG inflammatory foci in the SG of NOD mice, the expression of soluble CD40:Fc did not lead to reduced overall inflammation and/or improved salivary gland function. These data indicate possible redundancy of the CD40 pathway in the SG and suggests that targeting CD40 alone may not be sufficient to alter the disease phenotype.

Novel autoantibodies in Sjogren's syndrome

Sjogren's syndrome (SS) is defined by autoantibodies to Ro and La. The current studies identified additional autoantibodies in SS to salivary gland protein 1 (SP-1), carbonic anhydrase 6 (CA6) and parotid secretory protein (PSP). These autoantibodies were present in two animal models for SS and occurred earlier in the course of the disease than antibodies to Ro or La. Patients with SS also produced antibodies to SP-1, CA6 and PSP. These antibodies were found in 45% of patients meeting the criteria for SS who lacked antibodies to Ro or La. Furthermore, in patients with idiopathic xerostomia and xerophthalmia for less than 2 years, 76% had antibodies to SP-1 and/or CA6 while only 31% had antibodies to Ro or La. Antibodies to SP-1, CA6 and PSP may be useful markers for identifying patients with SS at early stages of the disease or those that lack antibodies to either Ro or La.

[Progress in understanding the pathogenesis of Sjögren's syndrome in non-obese diabetic mice]

Sjögren's syndrome is a chronic autoimmune disease, the pathogenesis of which still remains to be explored. Non-obese diabetic (NOD) mouse, presenting impairment of secretory function as well as the development of sialoadenitis, which is in common with human Sjögren's syndrome, is considered as one of the appropriate animal models for the study of Sjögren's syndrome. With regard to genetic factors, apoptosis, autoantibodies and cytokines, this paper reviewed the progress in understanding the pathogenesis of Sjögren's syndrome in NOD mice.