Current issues in the diagnosis and treatment of Sjögren's syndrome

Microbiome alterations in primary Sjögren's syndrome: Regional dysbiosis and microbiome-targeted therapeutic strategies

Primary Sjögren's syndrome (pSS) is a complex autoimmune disease characterized by diverse clinical manifestations. While xerophthalmia and xerostomia are hallmark symptoms, the disease often involves multiple organ systems, including the kidneys, lungs, nervous system, and gastrointestinal tract, leading to systemic morbidity in severe cases. Despite extensive research, the precise pathogenesis of pSS remains unclear, likely involving infectious, hormonal, and genetic factors. Emerging evidence highlights the microbiome as a key contributor to autoimmune diseases, including pSS. Dysbiosis in the oral, ocular, gut, and genital microbiomes plays a critical role in disease onset, progression, and variability. This review summarizes current findings on microbiome alterations in pSS, emphasizing their role in pathogenesis and clinical features, and explores microbiome-targeted therapies. Understanding the role of the microbiome in pSS pathophysiology could advance disease management and inspire targeted therapeutic strategies.

Insights into the Correlation and Immune Crosstalk Between COVID-19 and Sjögren's Syndrome Keratoconjunctivitis Sicca via Weighted Gene Coexpression Network Analysis and Machine Learning

Background: Although autoimmune complications of COVID-19 have aroused concerns, there is no consensus on its ocular complications. Sjögren's syndrome is an autoimmune disease accompanied by the ocular abnormality keratoconjunctivitis sicca (SS-KCS), which may be influenced by COVID-19. Thereby, we explored the possible interaction between COVID-19 and SS-KCS, and we aimed to elucidate the potential correlated mechanism. Methods: Differentially expressed genes (DEGs) in COVID-19 and SS-KCS transcriptome data obtained from the gene expression omnibus database were identified, and COVID-19-related genes were screened using weighted gene coexpression network analysis. Common genes were verified using four machine-learning diagnostic predictors. The clinical relationship between the two common hub genes of COVID-19 was analyzed. Finally, the immune cell types infiltrating the microenvironment in the COVID-19 dataset were analyzed using CIBERSORT, and the interrelation between key genes and differentially infiltrating immune cells was verified via Pearson correlation. Results: Ten potential primary hub mRNAs were screened by intersecting the COVID-19 DEGs, SS-KCS DEGs, and WGCNA genes. After a multifaceted evaluation using four mainstream machine-learning diagnostic predictors, the most accurate and sensitive random forest model identified CR1 and TAP2 as the common hub genes of COVID-19 and SS-KCS. Together with the clinical information on COVID-19, the expression of CR1 and TAP2 was significantly correlated with the status and severity of COVID-19. CR1 and TAP2 were significantly positively correlated with M0 and M2 macrophages, neutrophils, and CD4+ memory resting T cells and negatively correlated with activated NK cells, monocytes, and CD8+ T cells. Conclusions: We validated the hub genes associated with both COVID-19 and SS-KCS, and we investigated the immune mechanisms underlying their interaction, which may help in the early prediction, identification, diagnosis, and management of SARS-CoV-2 infection-related SS-KCS syndrome or many other immune-related complications in the long COVID period.

IRT5 Probiotics Changes Immune Modulatory Protein Expression in the Extraorbital Lacrimal Glands of an Autoimmune Dry Eye Mouse Model

Purpose

While the association between the gut microbiome and the immune system has been studied in autoimmune disorders, little is known about ocular disease. Previously we reported that IRT5, a mixture of five probiotic strains, could suppress autoimmune dry eye. In this study, we investigated the mechanism by which IRT5 performs its immunomodulatory function in a mouse model of autoimmune dry eye.

Methods

NOD.B10.H2b mice were used as an autoimmune dry eye model. Either IRT5 or PBS was gavaged orally for 3 weeks, with or without 5 days of antibiotic pretreatment. The effects on clinical features, extraorbital lacrimal gland and spleen proteins, and fecal microbiota were analyzed.

Results

The ocular staining score was lower, and tear secretion was higher, in the IRT5-treated groups than in the PBS-treated groups. After IRT5 treatment, the downregulated lacrimal gland proteins were enriched in the biological processes of defense response and immune system process. The relative abundances of 33 operational taxonomic units were higher, and 53 were lower, in the feces of the IRT5-treated groups than in those of the PBS-treated groups. IRT5 administration without antibiotic pretreatment also showed immunomodulatory functions with increases in the Lactobacillus helveticus group and Lactobacillus hamsteri. Additional proteomic assays revealed a decrease of proteins related to antigen-presenting processes in the CD11b⁺ and CD11c⁺ cells of spleen in the IRT5-treated groups.

Conclusions

Changes in the gut microbiome after IRT5 treatment improved clinical manifestations in the autoimmune dry eye model via the downregulation of antigen-presenting processes in immune networks.

miR-744-5p contributes to ocular inflammation in patients with primary Sjogrens Syndrome

In primary Sjögren’s syndrome (pSS) the exocrine glands become infiltrated with lymphocytes instigating severe damage to the salivary and lacrimal glands causing dry eyes and dry mouth. Previous investigations have suggested that dysregulated localized and systemic inflammation contributes to the development and pathogenesis of pSS. A miR microarray performed in primary human conjunctival epithelial cells (PECs) demonstrated significant differences in miR expression at the ocular surface between pSS patients and healthy controls. MicroRNA-744-5p (miR-744-5p) was identified as being of particular interest, as its top predicted target is Pellino3 (PELI3), a known negative regulator of inflammation. Validation studies confirmed that miR-744-5p expression is significantly increased in PECs from pSS patients, whilst PELI3 was significantly reduced. We validated the miR-744 binding site in the 3’ untranslated region (UTR) of PELI3 and demonstrated that increasing PELI3 levels with a miR-744-5p antagomir in an inflammatory environment resulted in reduced levels of IFN dependent chemokines Rantes (CCL5) and CXCL10. These results reveal a novel role for miR-744-5p in mediating ocular inflammation via Pellino3 expression in pSS patients and suggest that miR-744-5p may be a potential therapeutic target for the management of severe dry eye disease and ocular inflammation in pSS patients.

Aspirin Triggered Resolvin D1 reduces inflammation and restores saliva secretion in a Sjögren's syndrome mouse model

OBJECTIVES

SS is characterized by chronic inflammation of the salivary glands leading to loss of secretory function, thereby suggesting specialized pro-resolving mediators targeting inflammation to be a viable option for treating SS. Previous studies demonstrated that aspirin-triggered resolvin D1 (AT-RvD1) prevents chronic inflammation and enhances saliva secretion in a SS-like mouse model when applied before disease onset. However, this therapy cannot be used in SS patients given that diagnosis occurs post-disease onset and no reliable screening methods exist. Therefore, we examined whether treatment with AT-RvD1 reduces SS-like features in a mouse model post-disease onset.

METHODS

Tail vein injections were performed in a SS-like mouse model both with and without AT-RvD1 post-disease onset for 8 weeks, with salivary gland function and inflammatory status subsequently determined.

RESULTS

Treatment of a SS-like mouse model with AT-RvD1 post-disease onset restores saliva secretion in both females and males. Moreover, although AT-RvD1 treatment does not reduce the overall submandibular gland lymphocytic infiltration, it does reduce the number of T helper 17 cells within the infiltrates in both sexes. Finally, AT-RvD1 reduces SS-associated pro-inflammatory cytokine gene and protein expression levels in submandibular glands from female but not male mice.

CONCLUSION

AT-RvD1 treatment administered post-disease onset reduces T helper 17 cells and successfully restores salivary gland function in a SS mouse model with variable effects noted by sex, thus warranting further examination of both the causes for the sex differences and the mechanisms responsible for the observed treatment effect.

Lymphoepithelial Sialadenitis Involving HIV-Infected and Sjogren Syndrome Patients: A Cytologic Study

Lymphoepithelial salivary gland cysts are rarely seen in autoimmune diseases particularly Sjogren syndrome as well as in HIV for which medical management is advocated. To study the morphology of these cysts, correlate with the disease process and assess the final outcome. Case series. Fine needle aspiration clinic. HIV-infected and autoimmune disease patients with lymphoepithelial cysts. Antiretroviral therapy for HIV-patients and anti-inflammatory drugs for Sjogren syndrome. Three HIV-infected patients (two children and one adult) and three middle aged female patients presented with parotid and submandibular cysts, two of which were bilateral along with submandibular (one each in the HIV and the autoimmune group). In the adult HIV-patient, the cyst was found at the inception of the disease while the other pediatric HIV-patients just crossed a decade. Of the other three cases of Sjogren syndrome, two were primary and one, secondary to rheumatoid arthritis. All the cysts regressed completely with treatment of the respective diseases which was confirmed by ultrasonograms. Lymphoepithelial cysts are produced by release of serous secretion by the acinar and ductal cells within the epithelial islands in the process of their destruction. Possibly, antibody mediated increased secretion in the initial stages also plays a role. Lymphoepithelial cysts of HIV patients may occur in the course of treatment, not necessarily in the beginning, though it resolves spontaneously. Lymphoepithelial cysts of primary or secondary Sjogren syndrome may be repressed sufficiently by anti-inflammatory/immunosuppressant treatment.

Elevated CCL19/CCR7 Expression During the Disease Process of Primary Sjögren's Syndrome

Primary Sjögren's syndrome (pSS) is a common chronic autoimmune disease characterized by a high prevalence of autoantibodies and lymphocyte-mediated exocrine gland damage. To enhance our understanding of the mechanisms underlying the progression of the disease and to discover potential biomarkers for the early diagnosis of pSS, we applied RNA sequencing to compare the gene expression patterns in minor salivary glands between pSS patients and non-pSS. A total of 293 differentially expressed genes (DEGs) were detected in pSS vs. non-pSS (FDR < 0.05, fold changes > 2). Of these DEGs, 285 (97.26%) were up-regulated, with most being involved in immune system activation, especially in the formation of the immunological synapse. Significantly elevated CCL19/CCR7 expression in the salivary gland was found to be related to anti-Sjögren's syndrome-related antigen A (SSA) antibody and IgG levels in pSS patients, which was further confirmed in a larger cohort. Up-regulated gene expression showed strong discriminatory accuracy in identifying pSS with area under the curve of 0.98 using receiver operating characteristic curve analysis. In conclusion, gene expression changes in pSS include strong markers of immunological activation and have good discriminatory power in identifying patients with pSS.

The potential relationship between Flammer and Sjögren syndromes: the chime of dysfunction

Flammer syndrome (FS) is a term to blanket a cluster of vascular and nonvascular signs and symptoms linked to primary vascular dysregulation (PVD), increased sensitivity to various stimuli (stress, drugs, etc.) and altered sense regulation such as pain, smell and thirst perception. On one hand, disruption of blood barrier and homeostasis of the body are the main targets of vascular irregularity. Inflammation and immune disorders including autoimmunity are considered as a consequence of the abnormal vascular regulation processes. On the other hand, decreased thirst feeling typical for FS-affected individuals may lead to extensive body dehydration resulting in dry eye appearance and breast cancer (BC) risk, amongst others. To this end, recent research demonstrated FS as linked to BC development and progression into the metastatic disease. On the other side, Sjögren syndrome (SS) is an autoimmune disease characterised by a progressive sicca syndrome associated with the dry eye symptoms, specific immunologic complex and/or significant infiltrate at minor salivary gland biopsy. SS is relatively frequent, with a clinical diagnosis predominantly amongst women. Its physiopathology is a complex battery of both environmental and genetic factors. If left untreated, SS may be associated with and/or resulted in severe arthritis and the development of B cell lymphoma. In this mini-review, we summarise the facts and hypotheses connecting FS and SS symptoms together and mechanisms potentially overlapping in both syndromes. Unraveling the common denominators between these two syndromes not only providing more evidence for interaction between altered sense regulation, vascular dysregulation, immune system dysfunction but also focusing on the individual outcomes in terms of severity grade and potential complications exploring novel diagnostic, prognostic and treatment modalities. Multi-professional considerations presented here are an example how to effectively enter the new era of preventive, predictive and personalised medicine benefiting the patients and healthcare system as the whole.

Epigenetic Signatures of Salivary Gland Inflammation in Sjögren's Syndrome

Objective

Sjögren's syndrome (SS) is a complex multisystem autoimmune disease that results in progressive destruction of the exocrine glands. The purpose of this study was to characterize epigenetic changes in affected gland tissue and describe the relationship of these changes to known inflammatory processes.

Methods

A genome‐wide DNA methylation study was performed on human labial salivary gland (LSG) biopsy samples obtained from 28 female members of the Sjögren's International Collaborative Clinical Alliance (SICCA) Registry. Gland tissue was methylotyped using the Illumina HumanMethylation450 BeadChip platform, followed by rigorous probe‐filtering and data‐normalization procedures.

Results

A genome‐wide case–control study of 26 of the 28 subjects revealed 7,820 differentially methylated positions (DMPs) associated with disease status, including 5,699 hypomethylated and 2,121 hypermethylated DMPs. Further analysis identified 57 genes that were enriched for DMPs in their respective promoters; many are involved in immune response, including 2 previously established SS genetic risk loci. Bioinformatics analysis highlighted an extended region of hypomethylation surrounding PSMB8 and TAP1, consistent with an increased frequency of antigen‐presenting cells in LSG tissue from the SS cases. Transcription factor motif enrichment analysis revealed the specific nature of the genome‐wide methylation differences, demonstrating colocalization of SS‐associated DMPs with stress‐ and immune response–related motifs.

Conclusion

Our findings underscore the utility of CpG methylotyping as an independent probe of active disease processes in SS, offering unique insights into the composition of disease‐relevant tissue. Methylation profiling implicated several genes and pathways previously thought to be involved in disease‐related processes, as well as a number of new candidates.

Dry eye management in a Sjögren's syndrome mouse model by inhibition of p38-MAPK pathway

Background

To investigate the therapeutic effect of p38-MAPK inhibitor, SB203580, on dry eye in a mouse model of Sjögren’s syndrome (MRL/lpr mice).

Methods

18 female BALB/c mice and 44 female MRL/lpr mice were included. Mice were randomly assigned to the control or treatment group. The expression of phospho-p38 MAPK in lacrimal glands of BALB/c mice was determined by Western blot analysis following IL-1β treatment at various time points. Different doses of SB203580 were injected into lacrimal glands of MRL/lpr mice and phenol red thread test was performed seven days post-injection. Moreover, the levels of acetylcholine and norepinephrine expression in lacrimal glands of MRL/lpr mice were measured using spectrofluoremetric assay and the histopathology of lacrimal glands was also evaluated.

Results

The expression of p-p38 MAPK in lacrimal glands of BALB/c mice gradually increased following incubation with IL-1β ex vivo. Injection of SB203580 into lacrimal glands significantly improved the results of phenol red thread test in MRL/lpr mice. In addition, the secretions of acetylcholine and norepinephrine increased significantly compared to the control group. Less lymphocytes infiltration was observed in pathological section of lacrimal glands following SB203580 injection.

Conclusions

Our results indicate that the activation of p38-MAPK pathway plays an important role in dry eye of a Sjögren’s syndrome mouse model. Inhibition of p38-MAPK pathway by SB203580 might have potential therapeutic effect on Sjögren’s syndrome associated dry eye.

Virtual slides

The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1256849631103092.

Targeting TNF-α suppresses the production of MMP-9 in human salivary gland cells

OBJECTIVE

Tumour necrosis factor-α (TNF-α) is a pleiotropic cytokine that plays an essential role in inflammation and apoptosis. Our previous study suggested that TNF-α-induced activation of matrix metalloproteinase-9 (MMP-9) resulted in the destruction of acinar tissue in the salivary glands of patients with Sjögren's syndrome (SS) via disruption of the acinar cell-basement membrane. Recently, a wide array of biological agents has been designed to inhibit TNF, including etanercept and adalimumab. In this study, we demonstrate the suppressive effect of anti-TNF agents on TNF-α-induced MMP-9 production in NS-AV-AC, an immortalized human salivary gland acinar cell line.

MATERIALS AND METHODS

NS-AV-AC cells were treated with etanercept or adalimumab after TNF-α treatment. MMP-9 production and enzymatic activity were, respectively, visualized by real-time PCR and ELISA assay, and evaluated by gelatin zymography, and apoptosis was evaluated by DNA fragmentation assay.

RESULTS

TNF-α induced the production of MMP-9 in NS-SV-AC cells. However, this production was greatly inhibited by treatment with etanercept or adalimumab. In addition, TNF-α-induced DNA fragmentation was prevented by treatment with etanercept or adalimumab.

CONCLUSIONS

These results may indicate that anti-TNF agents would have therapeutic efficacy for preventing destruction of the acinar structure in the salivary glands of patients with SS.

Pharmacological cholinergic blockade stimulates inflammatory cytokine production and lymphocytic infiltration in the mouse lacrimal gland

PURPOSE

To investigate the effects of cholinergic blockade on inflammatory cell infiltration and cytokine production in the mouse lacrimal gland (LG).

METHODS

C57BL/6 mice were untreated (UT) or received subcutaneous injections of either scopolamine hydrobromide (SCOP; 0.5 mg/0.2 mL) or saline (SAL) four times daily for 2 or 5 days (2D, 5D). This was followed by a 7-day rest period in separate groups. Tear volume (cotton thread) and tear epidermal growth factor (EGF, by ELISA) concentrations were measured. Extraorbital LGs were surgically excised and sectioned or lysed for gene expression analysis. Immunohistochemistry evaluated immunophenotype of infiltrating cells. Expression of EGF and T helper (Th)-1, -2, and -17-associated cytokines in LGs was evaluated by real-time PCR. Goblet cell density was evaluated in periodic acid Schiff-stained conjunctival sections.

RESULTS

Tear volume and EGF protein levels were significantly reduced in SCOP5D mice compared with controls, indicating that cholinergic blockade decreased LG secretory function. LGs of SCOP2D and SCOP5D mice showed an increased density of CD4(+), CD11c+, CD11b+, and myeloperoxidase+ cells compared with UT controls. At day 5, these cells were significantly elevated compared with SAL-treated counterparts. Elevated levels of IL-17A, IL-17R, IFN-γ, IL-12Rβ1, IL-2, IL-13, IL-6, IL-1β, and TNF-α transcripts were noted in SCOP2D mice and IFN-γ, TGF-β1, and IL-18R transcripts in SCOP5D mice.

CONCLUSIONS

Pharmacological blockade of lacrimal secretion induced a significant CD4(+) infiltration in the LG, mimicking Sjögren's syndrome. The mRNA expression profile revealed elevations of a mix of inflammatory cytokines and Th-1-associated factors.

Modeling Sjögren's syndrome with Id3 conditional knockout mice

The Id3 gene has been shown to play important roles in the development and function of broad tissue types including B and T cells. Id3 deficient mice develop autoimmune disease similar to human Sjögren's syndrome. Both B and T lymphocytes have been implicated to contribute to the disease phenotype in this disease model. In order to gain a better understanding of individual cell types in this disease model, we generated an Id3 conditional allele. An LckCre transgene was used to induce Id3 deletion in developing T cells. We showed that the Id3 gene was efficiently disrupted in early thymocyte development prior to T cell receptor (TCR)-mediated positive selection. Consequently, thymocyte maturation was impaired in the conditional knockout mice. These mice developed exocrinopathy starting at two months of age and subsequently exhibited high incidence of lymphocyte infiltration to salivary glands between eight and 12 months of age. This progressive feature of disease development is very similar to those observed in Id3 germline knockout mice. This study establishes a new model for investigating the relationship between T cell development and autoimmune disease. Our observation provides an experimental case that autoimmune disease may be induced by acquired mutation in developing T cells.

Dermatologic manifestations of Sjögren syndrome

BACKGROUND

Sjögren syndrome (SS) is a chronic autoimmune inflammatory disease that involves primarily the exocrine glands, resulting in their functional impairment. SS typically presents as dry eyes (xerophthalmia) and dry mouth (xerostomia). This process can manifest either as the independent phenomenon of primary SS or as secondary SS when found in the context of another autoimmune process, most commonly rheumatoid arthritis or systemic lupus erythematosus. Nearly half of the patients with SS develop cutaneous manifestations, which may include dry skin (xeroderma), palpable and nonpalpable purpura, and/or urticaria-like lesions. These cutaneous manifestations have been underemphasized because they are often overshadowed by the more prominent sicca symptoms. However, certain skin findings are of paramount clinical and prognostic importance as they confer an increased risk for the development of life-threatening conditions, including multisystem vasculitis and non-Hodgkin lymphoma.OBJECTIVE AND CONCLUSIONS:In this review, the cutaneous manifestations of primary SS are discussed, with an emphasis on those findings that portend an increased risk of mortality.

Role of mucins in the skin during benign and malignant conditions

Skin-related diseases comprise a major health challenge to the practicing physician, and constitute a significant psychological, social and financial burden to the society. Further, skin cancer, especially non-melanoma skin cancer is currently the leading type of malignancy in the Western world. Given the huge burden of skin diseases, there is growing emphasis on understanding their pathophysiology, and towards their early detection. Mucins are high-molecular weight O- and N-linked glycoproteins that have emerged in recent years as important molecules in maintaining health and in promoting or protecting against inflammation and cancer. They have also begun to emerge as highly specific diagnostic and prognostic markers and novel therapeutic targets in several malignant disorders. However, their role in cutaneous pathologies has remained largely obscured. The present review provides the expression patterns and proposed role of mucins in the healthy skin and various benign and malignant skin diseases. The review has immense clinical significance as the availability of highly specific reagents including monoclonal antibodies against mucins makes them extremely attractive targets for specific diagnosis and/or immunotherapy of benign and malignant cutaneous diseases.

Role of immune response to M3 muscarinic acethylcholine receptor in the pathogenesis of Sjögren's syndrome

Sjögren's syndrome (SS) is a chronic autoimmune disease characterized by lymphocytic infiltration of salivary glands, in which CD4(+) T cells are predominant. These infiltrating T cells play a crucial role in the generation of SS. Previous studies showed that autoantibodies and auto-reactive T cells against M3 muscarinic acethylcholine receptor (M3R) were detected in patients with SS. In this study, to reveal the pathological mechanisms underlying immune response against M3R, we tried to induce SS like sialoadenitis. M3R knockout (M3R(-/-)) mice were immunized with murine M3R peptides. Their splenocytes were isolated and transferred into Rag1 knockout (Rag1(-/-)) mice. Mononuclear cells infiltration was detected in salivary glands of Rag1(-/-) mice inoculated splenocytes of M3R(-/-) mice immunized with M3R peptides. Moreover we transferred CD3(+) cells from splenocytes of M3R(-/-) mice immunized with M3R peptides into Rag1(-/-) mice. In their salivary glands, mononuclear infiltration was also detected. These findings suggest that the immune response to M3R plays a crucial role in the generation of SS like sialoadenitis.

Aberrant localization of ezrin correlates with salivary acini disorganization in Sjogren's Syndrome

OBJECTIVES

To analyse whether the alterations in the structure and organization of microvilli in salivary acinar cells from SS patients are linked to changes in the expression and/or cellular localization of ezrin.

METHODS

Salivary gland (SG) acini from controls and SS patients were used to evaluate ezrin expression by western blot and localization of total and activated (phospho-Thr567) ezrin by IF and EM.

RESULTS

In acini from control labial SGs, ezrin was located predominantly at the apical pole and to a lesser extent at the basal region of these cells. Conversely, in acini extracts from SS patients, ezrin showed significantly elevated levels, which were accompanied with localization mostly at the basal region. Moreover, F-actin maintained its distribution in both the apical region and basolateral cortex; however, it was also observed in the acinar cytoplasm. Phospho-ezrin (active form) was located exclusively at the apical pole of acinar cells from control subjects and abundantly located at the basal cytoplasm in SS samples. These results were confirmed by immunogold studies.

CONCLUSIONS

The decrease of ezrin and phospho-ezrin at the apical pole and the cytoplasmic redistribution of F-actin suggest an altered interaction between the F-actin-cytoskeleton and plasma membrane in SS patient acini, which may explain the microvilli disorganization. These alterations could eventually contribute to SG hyposecretion in SS patients.

Reduced sulfation of muc5b is linked to xerostomia in patients with Sjögren syndrome

OBJECTIVES

MUC5B contains sulfated and sialylated oligosaccharides that sequester water required for moisturising the oral mucosa. Xerostomia, in patients with Sjögren syndrome, is generally associated with reduced quantities, rather than altered properties, of saliva. Here, we determined the amount of MUC5B (mRNA and protein) as well as sulfation levels in salivary glands of patients with normal or altered unstimulated salivary flow. Localisation of MUC5B and sulfated MUC5B, as well as total levels sulfated groups were determined and compared with acini basal lamina disorganisation.

PATIENTS AND METHODS

In all, 18 patients with normal or altered unstimulated salivary flow and 16 controls were studied. MUC5B mRNA and protein were evaluated in salivary glands by semiquantitative RT-PCR and Western blot analysis. MUC5B sulfation was determined by Western blotting. MUC5B and sulfo-Lewis(a) antigen localisation were assessed by immunohistochemistry. The total amount of sulfated oligosaccharides was determined microdensitometrically.

RESULTS

No significant differences were detected in MUC5B mRNA and protein levels between controls and patients, while sulfo-Lewis(a) antigen levels were lower in patients. The number of sulfo-Lewis(a) positive mucous acini was reduced in patients but no correlation was observed between lower levels of sulfation and unstimulated salivary flow. Microdensitometric data confirmed the presence of reduced sulfated oligosaccharides levels in mucous acini from patients with highly disorganised basal lamina.

CONCLUSION

Disorganisation of the basal lamina observed in patients with Sjögren syndrome may lead to dedifferentiation of acinar mucous cells and, as a consequence, alter sulfation of MUC5B. These changes are suggested to represent a novel mechanism that may explain xerostomia in these patients.

T lymphocytes in Sjögren's syndrome: contributors to and regulators of pathophysiology

Sjögren's syndrome is a chronic autoimmune disorder characterized by lymphocytic infiltration and malfunction of the exocrine glands, resulting in dry mouth and eyes. This multigenic and multifunctional disease can present as primary Sjögren's syndrome or secondary to an underlying connective tissue disease. Immune activation subsequent to activation or apoptosis of glandular epithelial cells in genetically predisposed individuals may expose autoantigens, which engage self-perpetuating T cell dependent autoimmune sequelae. The cellular and molecular context of this immune response may drive proinflammatory (Th1 and Th17) and restrain inhibitory (Treg) pathways. Inability to suppress the immune response results in persistent tissue damage and compromised function of salivary and lacrimal glands. Defining the contributions of participating T cells may unravel strategies for therapeutic intervention.

Sjogrens syndrome as failed local immunohomeostasis: prospects for cell-based therapy

Sjogrens syndrome has been estimated to affect between 0.2% and 2% or more of the population. It is an autoimmune disease with the hallmark histopathology of focal, periductal, and perivascular CD4(+) cell infiltration of the lacrimal and salivary glands. The immunohistopathology is typically associated with severe lacrimal and salivary dysfunctions, which contribute to debilitating ocular surface and oral symptoms. The quality of life of patients with Sjogrens syndrome often is degraded further by serious, multisystemic manifestations, and they are subject to a forty-fold increased risk of developing B cell lymphomas. In normal lacrimal glands, secretory epithelial cells, autoimmune effector lymphocytes, and regulatory lymphocytes can be seen as collaborating to maintain a local immunohomeostasis. The epithelium contributes by secreting immunomodulatory paracrine factors and also by continuously exposing autoantigens, which thereby become available for uptake by professional antigen presenting cells (APCs). Local or systemic perturbations may initiate autoimmune pathophysiology by impairing the replacement of normally-turning-over regulatory cells, by altering epithelial production of immunomodulatory paracrine factors, by inducing intact epithelial cells to begin secreting previously cryptic epitopes (epitopes that previously were not available to bind to major histocompatibility complex (MHC) molecules and so could not be recognized by T cell antigen receptors), and by inducing epithelial cells to begin expressing MHC Class II molecules and presenting formerly cryptic epitopes directly to CD4(+) cells. This process has been modeled ex vivo with mixed cell reactions comprised of isolated epithelial cells and autologous lymphocytes. This development has occurred as studies of anterior chamber-associated immune deviation (ACAID) and other immunoregulatory phenomena have elucidated the origins and functions of several different kinds of regulatory lymphocytes and shown that regulatory lymphocytes can be generated ex vivo. It now is possible to envision strategies for exploiting each possible mode of epithelial autoantigen exposure to produce therapeutic regulatory cells that might be capable of re-establishing normal immunohomeostasis. Consideration of the hypothetical therapies identifies a number of basic questions that warrant investigation.

B-lymphocyte depletion ameliorates Sjögren's syndrome in Id3 knockout mice

Sjögren's syndrome is an autoimmune disease in which immune cells chronically attack the lachrymal and salivary glands. The Id3 knockout mouse is a newly established animal model for primary Sjögren's syndrome. To address the role of B cells in Sjögren's syndrome and autoimmune disease, we studied the effect of CD20 monoclonal antibody treatment on the disease in Id3 knockout mice. Antibody treatment at 2-month intervals led to efficient and sustained B-cell depletion in Id3 knockout mice. A significant improvement of histopathology was observed accompanied by the recovery of saliva secretory function after CD20 antibody treatment. We further show that serum immunoglobulin G3, which is abnormally high in untreated Id3 knockout mice, was reduced after CD20 antibody treatment. This study establishes a new animal model for immunotherapy of Sjögren's symptoms and suggests a possible link between immunoglobulin G3 and disease pathology in Id3 knockout mice.

Sjögren's syndrome in dermatology

Sjogren's Syndrome (SS) is a systemic autoimmune disease characterized by dry eyes (keratoconjunctivis sicca) and dry mouth (xerostomia). To fulfill diagnostic criteria, patients must have objective signs of dryness on examination and laboratory confirmation of an autoimmune process as evidenced by a positive autoantibody to SS-A antigen or a characteristic lip biopsy. SS may exist as a primary condition or in association with other systemic autoimmune disorders (termed secondary SS) such as rheumatoid arthritis, systemic lupus erythematous (SLE), progressive systemic sclerosis (scleroderma), or dermatomyositis. Exclusions to the diagnosis include pre-existing lymphoma, hepatitis C or HIV infection. Pathogenesis involves both genetic (especially HLA-DR) and environmental factors. Both T-cells and B-cells are involved in the generation of cytokines and chemokines within the glands. The epithelial cells of the glands also play a role in pathogenesis. The dermatologic manifestations range from drynessness (sicca) and its complications to vasculitis. There is a significant overlap in the clinical manifestations, as well as treatment, of SS and SLE. However, SS patients require special attention to the complications of ocular dryness (keratocojunctivitis sicca and blepharitis) and oral dryness (rapid tooth loss and oral candidiasis) SS patients have a markedly increased risk of lymphoma and enlarged lymph nodes or persistently enlarged parotid/submandibular glands that require further evaluation.

Current status of gene delivery and gene therapy in lacrimal gland using viral vectors

Gene delivery is one of the biggest challenges in the field of gene therapy. It involves the efficient transfer of transgenes into somatic cells for therapeutic purposes. A few major drawbacks in gene delivery include inefficient gene transfer and lack of sustained transgene expression. However, the classical method of using viral vectors for gene transfer has circumvented some of these issues. Several kinds of viruses, including retrovirus, adenovirus, adeno-associated virus, and herpes simplex virus, have been manipulated for use in gene transfer and gene therapy applications. The transfer of genetic material into lacrimal epithelial cells and tissues, both in vitro and in vivo, has been critical for the study of tear secretory mechanisms and autoimmunity of the lacrimal gland. These studies will help in the development of therapeutic interventions for autoimmune disorders such as Sjögren's syndrome and dry eye syndromes which are associated with lacrimal dysfunction. These studies are also critical for future endeavors which utilize the lacrimal gland as a reservoir for the production of therapeutic factors which can be released in tears, providing treatment for diseases of the cornea and posterior segment. This review will discuss the developments related to gene delivery and gene therapy in the lacrimal gland using several viral vector systems.

Pilocarpine hydrochloride for the treatment of xerostomia in patients with Sjögren's syndrome in Taiwan--a double-blind, placebo-controlled trial

Background/purpose

Sjögren's syndrome (SS) is characterized by diminished exocrine secretions with the resultant symptoms of dry mouth and dry eye. As genetic predisposition and ethnicity may alter the effectiveness of drug treatment, evaluation of the efficacy and safety of the secretagogue pilocarpine hy-drochloride in the treatment of xerostomia in patients with SS in different populations is needed.

Methods

Forty-four patients with SS were enrolled in this double-blind, placebo-controlled trial. Patients were randomized to receive 5 mg pilocarpine (Salagen) or placebo tablet four times daily for 12 weeks. Global evaluation and subjective responses of patients were assessed by questionnaires with visual analog scales and categorical checkboxes. Saliva production was also measured by modified Saxon's test.

Results

Pilocarpine treatment significantly improved global assessment of dry mouth, symptoms associated with dry mouth (mouth comfort, ability to sleep and ability to speak), and saliva production compared to placebo. The drug was well tolerated and the most common adverse effect was sweating (5/23, 21.7%) resulting from the muscarinic agonist action of the drug. No serious drug-related adverse effect was found in this study.

Conclusion

The results of this study suggest that therapy with 5 mg pilocarpine four times daily is effective, safe and well tolerated for the relief of oral symptoms in patients with SS in Taiwan.

IL-10 promoter -1082 polymorphism is associated with elevated IL-10 levels in control subjects but does not explain elevated plasma IL-10 observed in Sjögren's syndrome in a Hungarian cohort

The aim of this study was to investigate the frequency of the -1082 polymorphism of the interleukin-10 (IL-10) gene and the soluble IL-10 levels in Hungarian primary Sjögren's syndrome (SS) patients. Ninety-nine SS patients and 135 healthy volunteers were examined. Samples were analysed by the PCR restriction fragment length polymorphism method, and IL-10 plasma levels were assessed by a commercial enzyme-linked immunosorbent assay. IL-10 plasma levels were higher in the primary SS patients (36.4 +/- 57.5 pg/ml, n = 99) compared with the healthy subjects (9.9 +/- 20.3 pg/ml, n = 135, P = 10(-6)). The elevated IL-10 phenotype of SS patients was not associated with increased G allele frequency as reported earlier, while in the control group, we found higher IL-10 levels among the subjects who were carriers of the GG genotype (17.7 +/- 23.2 pg/ml) as compared with the other two genotype carriers (AA 8.98 +/- 16.5 and GA 8.5 +/- 21.1 pg/ml, P = 0.01). Our data do not support previous observations indicating an association between deregulated IL-10 secretion in SS and higher G allele frequency. However, the results clearly demonstrate that GG homozygosity is associated with elevated IL-10 levels in apparently healthy subjects, but this cannot account for the IL-10-related specific disease features observed in SS. Thus, other genetic factors contribute to the clinical spectrum of this heterogeneous disease at least in the Hungarian population.

Effect of inflammation on lacrimal gland function

The lacrimal gland is the main contributor to the aqueous layer of the tear film. It secretes proteins, electrolytes and water, which helps to nourish and protect the ocular surface. Lacrimal gland secretion is primarily under neural control, which is achieved through a neural reflex arc. Stimuli to the ocular surface activate afferent sensory nerves in the cornea and conjunctiva. This in turn activates efferent parasympathetic and sympathetic nerves in the lacrimal gland to stimulate secretion. Sex steroid hormones are also important regulators of lacrimal gland functions. A decrease or lack of lacrimal gland secretion is the leading cause of aqueous tear deficient dry eye syndrome (DES). It has been suggested that DES is an inflammatory disorder that affects the ocular surface and the lacrimal gland. In several pathological instances, the lacrimal gland can become a target of the immune system and show signs of inflammation. This can result from autoimmune diseases (Sjögren's syndrome), organ transplantation (graft versus host disease), or simply as a result of aging. The hallmarks of lacrimal gland inflammation are the presence of focal lymphocytic infiltrates and increased production of proinflammatory cytokines. The mechanisms leading to lacrimal gland dysfunction are still poorly understood. Apoptosis, production of autoantibodies, hormonal imbalance, alterations in signaling molecules, neural dysfunction, and increased levels of proinflammatory cytokines have been proposed as possible mediators of lacrimal gland insufficiency in disease states.

c-Jun NH2-terminal kinase mediates interleukin-1beta-induced inhibition of lacrimal gland secretion

Sjögren's syndrome, an inflammatory disease affecting the lacrimal and salivary glands, is the leading cause of aqueous tear-deficient type of dry eye. We previously showed that interleukin-1beta (IL-1beta) protein is up regulated in the lacrimal gland of a murine model of Sjögren's syndrome and that exogenous addition of this cytokine inhibits neurotransmitter release and lacrimal gland protein secretion. In the present study we investigated the role of c-Jun NH2-terminal kinase (JNK) in IL-1beta-mediated inhibition of lacrimal gland secretion and tear production. In vitro, IL-1beta induced a time-dependent activation of JNK with a maximum 7.5-fold at 30 min. SP600125, a JNK inhibitor, inhibited, in a concentration-dependent manner, IL-1beta-induced activation of JNK with a maximum of 87% at 10(-4) m. In vivo, IL-1beta stimulated JNK and the expression of the inducible isoform of nitric oxide synthase (iNOS). IL-1beta inhibited high KCl and adrenergic agonist induced protein secretion by 85% and 66%, respectively. SP600125 alleviated the inhibitory effect of IL-1beta on KCl- and agonist-induced protein secretion by 79% and 47%, respectively, and completely blocked the expression of iNOS. Treatment for 7 days with SP600125 increased tear production in a murine model of Sjögren's syndrome dry eye. We conclude that JNK plays a pivotal role in IL-1beta-mediated inhibition of lacrimal gland secretion and subsequent dry eye.

Crohn's disease associated with Sweet's syndrome and Sjögren's syndrome treated with infliximab

The association of Crohn's disease (CD) and Sweet's syndrome is rare and the presence of Sjögren's syndrome in Crohn's disease is even rarer, with only three reports found in the literature. We describe two cases of Crohn's disease associated with Sweet's syndrome, one of which is the first case of CD and Sweet's concomitantly associated with Sjögren's syndrome. Both cases responded rapidly to Infliximab therapy with complete resolution of the skin lesions.

Sjögren's syndrome

Sjögren's syndrome is a chronic autoimmune disorder of the exocrine glands with associated lymphocytic infiltrates of the affected glands. Dryness of the mouth and eyes results from involvement of the salivary and lacrimal glands. The accessibility of these glands to biopsy enables study of the molecular biology of a tissue-specific autoimmune process. The exocrinopathy can be encountered alone (primary Sjögren's syndrome) or in the presence of another autoimmune disorder such as rheumatoid arthritis, systemic lupus erythematosus, or progressive systemic sclerosis. A new international consensus for diagnosis requires objective signs and symptoms of dryness including a characteristic appearance of a biopsy sample from a minor salivary gland or autoantibody such as anti-SS-A. Exclusions to the diagnosis include infections with HIV, human T-lymphotropic virus type I, or hepatitis C virus. Therapy includes topical agents to improve moisture and decrease inflammation. Systemic therapy includes steroidal and non-steroidal anti-inflammatory agents, disease-modifying agents, and cytotoxic agents to address the extraglandular manifestations involving skin, lung, heart, kidneys, and nervous system (peripheral and central) and haematological and lymphoproliferative disorders. The most difficult challenge in diagnosis and therapy is patients with symptoms of fibromyalgia (arthralgia, myalgia, fatigue) and oral and ocular dryness in the presence of circulating antinuclear antibodies.

Endothelıal dysfunctıon ın patıents wıth prımary Sjögren’s syndrome

The aim of this study was to determine the endothelial function in patients with primary Sjögren's syndrome (SS). We also aimed to determine whether endothelial (dys)function correlates with extraglandular manifestations, specific autoantibodies and the severity of salivary gland involvement of SS. Endothelium-dependent vasodilation and endothelium-independent vasodilation of the brachial artery were assessed by a high-resolution ultrasound on 25 patients with primary SS and on 29 healthy controls. Patients with primary SS had significantly less mean endothelium-dependent vasodilation than did controls (3.0 +/- 0.4% vs 4.2 +/- 0.3%; p = 0.012). Endothelium-independent vasodilation induced by sublingual glycerol trinitrate was not different between the two groups (12.9 +/- 1.4% vs 14.1 +/- 1.2%; p = 0.86). We concluded that endothelium-dependent vasodilation was impaired in primary SS patients, in particular those presenting with Raynaud's phenomenon, when compared with the healthy controls and this impairment was not associated with the presence of RF, ANA, anti-Ro/SS-A, anti-La/SS-B and with the other extraglandular manifestations of the disease.

Etanercept in Sjögren's syndrome: a twelve-week randomized, double-blind, placebo-controlled pilot clinical trial

OBJECTIVE

To assess the safety and potential efficacy of etanercept in the treatment of Sjögren's syndrome (SS).

METHODS

This pilot study was a 12-week randomized, double-blind, placebo-controlled trial of etanercept, with 14 subjects in each group. Patients received 25 mg of etanercept or placebo (vehicle) by twice-weekly subcutaneous injection. Patients met the American-European Consensus Group criteria for SS. The primary outcome required at least 20% improvement from baseline values for at least 2 of the following 3 domains: subjective or objective measures of dry mouth, subjective or objective measures of dry eyes, and IgG level or erythrocyte sedimentation rate (ESR).

RESULTS

Of the 14 patients taking etanercept, 11 had primary SS and 3 had SS secondary to rheumatoid arthritis. Baseline measures did not differ between the 2 groups. Three etanercept-treated patients and 1 placebo-treated patient did not complete the trial. Five etanercept-treated patients and 3 placebo-treated patients showed improvement from baseline in the primary outcome variable at 12 weeks, but the difference was not statistically significant. There were no significant differences between the groups for changes in subjective measures of oral or ocular symptoms (by visual analog scale), the IgG level, Schirmer I test result, van Bijsterveld score, or salivary flow. At 12 weeks, the ESR had decreased in the etanercept group compared with baseline (P = 0.004); however, the mean reduction was only 18.6%.

CONCLUSION

We found no evidence to suggest that treatment with etanercept at a dosage of 25 mg twice weekly for 12 weeks was clinically efficacious in SS. A larger trial will be necessary to definitively address the efficacy of etanercept in the treatment of SS.

Therapeutic effect of cevimeline on dry eye in patients with Sjögren's syndrome: a randomized, double-blind clinical study

PURPOSE

Sjögren's syndrome (SS) is a systemic autoimmune disease characterized by salivary and lacrimal glandular destruction leading to symptoms of dry mouth and dry eye. Dryness can also occur in the absence of glandular destruction. Patients with SS have autoantibodies that bind to muscarinic acetylcholine receptors in the exocrine glands. Recently, a muscarinic acetylcholine receptor agonist, cevimeline, has been approved for use against symptoms of dry mouth in patients with SS. In this study, the efficacy of cevimeline in improving symptoms of dry eye was examined.

DESIGN

Prospective, randomized, double-blind, multi-center clinical study.

METHODS

Sixty patients were randomly assigned to three groups-placebo; cevimeline, 20 mg three times daily; or cevimeline, 30 mg three times daily-and received treatment for 4 weeks. Patients were evaluated before treatment, at week 2, at the end of treatment, and at the end of a 2- to 4-week follow-up period.

RESULTS

Compared with the placebo, statistically significant differences were seen with cevimeline, 20 mg three times daily, in subjective symptoms, tear dynamics, condition of the corneoconjunctival epithelium, and global improvement rating. No difference was found among the three groups regarding the safe use of the drug.

CONCLUSIONS

These results indicate that cevimeline, 20 mg three times daily, is safe and effective in improving symptoms of dry eye in patients with SS. Additional studies, with larger patient populations, are needed to further assess the effectiveness of cevimeline for dry eye.

Tumor necrosis factor inhibitor gene expression suppresses lacrimal gland immunopathology in a rabbit model of autoimmune dacryoadenitis

PURPOSE

To evaluate the effect of tumor necrosis factor (TNF) inhibitor protein on lacrimal gland immunopathology and ocular surface disease resulting from induced dacryoadenitis.

METHODS

Autoimmune dacryoadenitis was induced in rabbits by injecting the lacrimal glands with peripheral blood lymphocytes (PBLs) activated by 5 days of coculture with autologous acinar cells in a mixed cell reaction. In the treated group, an adenoviral vector carrying the TNF inhibitor gene (AdTNFRp55-Ig) was concurrently injected with AMCR-PBL. Tear production was monitored by Schirmer test, and tears were collected for detection of TNF-inhibitor protein. Frozen sections of the glands were immunostained for expression of CD4, CD8, rabbit thymic lymphocyte antigen (RTLA), and CD18. Histological sections of lacrimal glands were examined using the TUNEL technique to monitor apoptosis.

RESULTS

Soluble TNF-inhibitor protein was detected by ELISA in tears, with titers at a maximum on day 3, declining by day 7, and undetectable by day 14. Tear production declined in the induced dacryoadenitis group but did not change when glands had been treated with AdTNFRp55-Ig simultaneously with disease induction. Tear break-up time and rose bengal staining properties were not altered by treatment. Fourteen days after the glands were injected with activated PBLs, focal mononuclear cell infiltrates were observed around ducts and venules, some of which assumed the high endothelial phenotype, and between acini. Immune cells in the infiltrates stained positive for CD4, RTLA, and CD18. Glands that received AdTNFRp55-Ig concurrently with activated PBLs had decreased numbers of CD4 cells, CD18 cells, RTLA, and apoptotic cells.

CONCLUSIONS

In vivo transduction of the lacrimal gland with AdTNFRIp55-Ig resulted in transient expression in the gland and the appearance of TNF-inhibitor protein in tears. The presence of soluble TNF-inhibitor protein partially suppressed the appearance of Sjögren's syndrome-like features of reduced tear production and the immunohistopathology associated with induced autoimmune dacryoadenitis but not tear break-up time and ocular surface disease. This may reflect immunoregulation in the lacrimal gland but not in the conjunctiva.

Extrahepatic manifestations of hepatitis C infection

Hepatitis C virus (HCV) affects 1.8% of the American population, and approximately 38% of patients with HCV will manifest symptoms of at least 1 extrahepatic manifestation during the illness. Renal disease, neuropathy, lymphoma, and Sjögren syndrome with or without mixed cryoglobulinemia are all strongly associated with HCV infection. Porphyria cutanea tarda and diabetes have also been linked to HCV. Most extrahepatic manifestations of chronic HCV infection are immunological, and the chronic infection seems to be necessary for their development. The molecular study of the unique way in which the HCV virus interacts with the human immune system is beginning to provide plausible explanations of the pathogenic role of HCV in some of these syndromes, but many pathogenetic links remain completely obscure.