Infliximab in patients with primary Sjögren's syndrome: a pilot study

British Society for Rheumatology guideline on management of adult and juvenile onset Sjögren disease

Sjögren disease (SD) is a chronic, autoimmune disease of unknown aetiology with significant impact on quality of life. Although dryness (sicca) of the eyes and mouth are the classically described features, dryness of other mucosal surfaces and systemic manifestations are common. The key management aim should be to empower the individual to manage their condition-conserving, replacing and stimulating secretions; and preventing damage and suppressing systemic disease activity. This guideline builds on and widens the recommendations developed for the first guideline published in 2017. We have included advice on the management of children and adolescents where appropriate to provide a comprehensive guideline for UK-based rheumatology teams.

The Future of Targeted Treatment of Primary Sjögren's Syndrome: A Focus on Extra-Glandular Pathology

Primary Sjögren's syndrome (pSS) is a chronic, systemic autoimmune disease defined by exocrine gland hypofunction resulting in dry eyes and dry mouth. Despite increasing interest in biological therapies for pSS, achieving FDA-approval has been challenging due to numerous complications in the trials. The current literature lacks insight into a molecular-target-based approach to the development of biological therapies. This review focuses on novel research in newly defined drug targets and the latest clinical trials for pSS treatment. A literature search was conducted on ClinicalTrials.gov using the search term "Primary Sjögren's syndrome". Articles published in English between 2000 and 2021 were included. Our findings revealed potential targets for pSS treatment in clinical trials and the most recent advances in understanding the molecular mechanisms underlying the pathogenesis of pSS. A prominent gap in current trials is in overlooking the treatment of extraglandular symptoms such as fatigue, depression, and anxiety, which are present in most patients with pSS. Based on dryness and these symptom-directed therapies, emerging biological agents targeting inflammatory cytokines, signal pathways, and immune reaction have been studied and their efficacy and safety have been proven. Novel therapies may complement existing non-pharmacological methods of alleviating symptoms of pSS. Better grading systems that add extraglandular symptoms to gauge disease activity and severity should be created. The future of pSS therapies may lie in gene, stem-cell, and tissue-engineering therapies.

Innate Immunity and Biological Therapies for the Treatment of Sjögren's Syndrome

Sjögren's syndrome (SS) is a systemic autoimmune disorder affecting approximately 3% of the population in the United States. This disease has a female predilection and affects exocrine glands, including lacrimal and salivary glands. Dry eyes and dry mouths are the most common symptoms due to the loss of salivary and lacrimal gland function. Symptoms become more severe in secondary SS, where SS is present along with other autoimmune diseases like systemic lupus erythematosus, systemic sclerosis, or rheumatoid arthritis. It is known that aberrant activation of immune cells plays an important role in disease progression, however, the mechanism for these pathological changes in the immune system remains largely unknown. This review highlights the role of different immune cells in disease development, therapeutic treatments, and future strategies that are available to target various immune cells to cure the disease.

How to treat Sjögren's syndrome

SS is a chronic, autoimmune disease of unknown aetiology for which there is no known curative treatment. Although dryness of the eyes and mouth are the classically described features, patients often experience drying of other mucosal surfaces and systemic manifestations, including fatigue and arthralgia. There is an association with other autoimmune diseases, especially thyroid disease, coeliac disease and primary biliary cholangitis. Systemic features may affect up to 70% and include inflammatory arthritis, skin involvement, haematological abnormalities, neuropathies, interstitial lung disease and a 5-10% lifetime risk of B cell lymphoma. Treatment should aim to empower patients to manage their condition; conserve, replace and stimulate secretions; prevent damage; and suppress underlying systemic disease activity.

Arthritis in primary Sjögren's syndrome: Characteristics, outcome and treatment from French multicenter retrospective study

OBJECTIVE

To describe the characteristics and the outcome of primary Sjögren Syndrome (pSS) associated arthritis and to compare the efficacy of different therapeutic regimen.

METHODS

We conducted a retrospective study using Club Rhumatisme and Inflammation (CRI) and French Internal Medicine Society (SNFMI) networks. All patients with a diagnosis of pSS and at least one episode of clinical and/or echographic synovitis were included. Patients with synovitis (cases) were compared to pSS patients without synovitis (controls).

RESULTS

57 patients (93% women) were included with a median age of 54 years [45-63]. Patients with synovitis had more frequently lymph node enlargement (12.3% vs. 1.8%, p = .007) and a higher ESSDAI score (8 [6-12] vs. 2 [1-4], p < .0001). There was no difference concerning CRP levels, rheumatoid factor and cyclic citrullinated peptide (CCP)-antibodies positivity. Among 57 patients with synovitis, 101 various treatment courses have been used during the follow-up of 40 [22.5-77] months. First treatment course consisted in steroids alone (3.5%), steroids in association (79%) with hydroxychloroquine (HCQ) (49%), methotrexate (MTX) (35%), rituximab (RTX) (5.3%) or other immunosuppressive drugs (7%). HCQ, MTX, and RTX were associated with a significant reduction of tender and swollen joint count, and a significant steroids-sparing effect. No difference could be shown for the joint response between these treatment regimens.

CONCLUSION

pSS articular manifestations may include synovitis which could mimic rheumatoid arthritis but differ by the absence of structural damage. Even if the use of HCQ, MTX, and RTX seem to be effective for joint involvement, the best regimen remains to be determined.

Clinical practice guideline for Sjögren's syndrome 2017

OBJECTIVES

The objective of this study is to develop clinical practice guideline (CPG) for Sjögren's syndrome (SS) based on recently available clinical and therapeutic evidences.

METHODS

The CPG committee for SS was organized by the Research Team for Autoimmune Diseases, Research Program for Intractable Disease of the Ministry of Health, Labor and Welfare (MHLW), Japan. The committee completed a systematic review of evidences for several clinical questions and developed CPG for SS 2017 according to the procedure proposed by the Medical Information Network Distribution Service (Minds). The recommendations and their strength were checked by the modified Delphi method. The CPG for SS 2017 has been officially approved by both Japan College of Rheumatology and the Japanese Society for SS.

RESULTS

The CPG committee set 38 clinical questions for clinical symptoms, signs, treatment, and management of SS in pediatric, adult and pregnant patients, using the PICO (P: patients, problem, population, I: interventions, C: comparisons, controls, comparators, O: outcomes) format. A summary of evidence, development of recommendation, recommendation, and strength for these 38 clinical questions are presented in the CPG.

CONCLUSION

The CPG for SS 2017 should contribute to improvement and standardization of diagnosis and treatment of SS.

Pathogenic role of endogenous TNF-α in the development of Sjögren's-like sialadenitis and secretory dysfunction in non-obese diabetic mice

Patients with Sjögren's syndrome (SS), an autoimmune disease primarily affecting exocrine glands, exhibit enhanced TNF-α expression in the saliva and salivary glands. However, the precise in vivo role of TNF-α during the initiation and development of SS is not clearly defined. The present study is undertaken to determine the function of endogenously produced TNF-α in the pathogenesis of SS in non-obese diabetic (NOD) mice, a model of this human disease. Administration of a neutralizing anti-TNF-α antibody to female NOD mice during the stage prior to disease onset significantly improved salivary secretion, indicating a remission of clinical symptoms of SS. TNF-α blockade also decreased the number of leukocyte foci and reduced the number of T cells and B cells in the submandibular glands (SMG). Moreover, TNF-α blockade reduced T-bet protein levels in the SMG, suggesting a decrease in T helper 1 and T cytotoxic 1 cells. These cellular changes induced by TNF-α neutralization were associated with a reduction in T- and B-cell chemoattractants CXCL9 and CXC13. In addition, TNF-α blockade markedly increased the expression level of tight junction protein claudin-1 and water channel protein aquaporin-5, two key factors required for normal salivary secretion, in the SMG. Collectively, these findings indicate that endogenous TNF-α has a pathogenic role in the development of SS in the NOD model of this disease.

Low-intensity pulsed ultrasound rescues insufficient salivary secretion in autoimmune sialadenitis

Introduction

Low-intensity pulsed ultrasound (LIPUS) has been known to promote bone healing by nonthermal effects. In recent studies, LIPUS has been shown to reduce inflammation in injured soft tissues. Xerostomia is one of the most common symptoms in Sjögren syndrome (SS). It is caused by a decrease in the quantity or quality of saliva. The successful treatment of xerostomia is still difficult to achieve and often unsatisfactory. The aim of this study is to clarify the therapeutic effects of LIPUS on xerostomia in SS.

Methods

Human salivary gland acinar (NS-SV-AC) and ductal (NS-SV-DC) cells were cultured with or without tumor necrosis factor-α (TNF-α; 10 ng/ml) before LIPUS or sham exposure. The pulsed ultrasound signal was transmitted at a frequency of 1.5 MHz or 3 MHz with a spatial average intensity of 30 mW/cm² and a pulse rate of 20 %. Cell number, net fluid secretion rate, and expression of aquaporin 5 (AQP5) and TNF-α were subsequently analyzed. Inhibitory effects of LIPUS on the nuclear factor κB (NF-κB) pathway were determined by Western blot analysis. The effectiveness of LIPUS in recovering salivary secretion was also examined in a MRL/MpJ/lpr/lpr (MRL/lpr) mouse model of SS with autoimmune sialadenitis.

Results

TNF-α stimulation of NS-SV-AC and NS-SV-DC cells resulted in a significant decrease in cell number and net fluid secretion rate (p < 0.01), whereas LIPUS treatment abolished them (p < 0.05). The expression changes of AQP5 and TNF-α were also inhibited in LIPUS treatment by blocking the NF-κB pathway. Furthermore, we found that mRNA expression of A20, a negative feedback regulator, was significantly increased by LIPUS treatment after TNF-α or interleukin 1β stimulation (NS-SV-AC, p < 0.01; NS-SV-DC, p < 0.05). In vivo LIPUS exposure to MRL/lpr mice exhibited a significant increase in both salivary flow and AQP5 expression by reducing inflammation in salivary glands (p < 0.01).

Conclusions

These results suggest that LIPUS upregulates expression of AQP5 and inhibits TNF-α production. Thus, LIPUS may restore secretion by inflamed salivary glands. It may synergistically activate negative feedback of NF-κB signaling in response to inflammatory stimulation. Collectively, LIPUS might be a new strategic therapy for xerostomia in autoimmune sialadenitis with SS.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0798-8) contains supplementary material, which is available to authorized users.

Which and How Many Patients Should Be Included in Randomised Controlled Trials to Demonstrate the Efficacy of Biologics in Primary Sjögren's Syndrome?

OBJECTIVE

The goal of this study was to determine how the choice of the primary endpoint influenced sample size estimates in randomised controlled trials (RCTs) of treatments for primary Sjögren's syndrome (pSS).

METHODS

We reviewed all studies evaluating biotechnological therapies in pSS to identify their inclusion criteria and primary endpoints. Then, in a large cohort (ASSESS), we determined the proportion of patients who would be included in RCTs using various inclusion criteria sets. Finally, we used the population of a large randomised therapeutic trial in pSS (TEARS) to assess the impact of various primary objectives and endpoints on estimated sample sizes. These analyses were performed only for the endpoints indicating greater efficacy of rituximab compared to the placebo.

RESULTS

We identified 18 studies. The most common inclusion criteria were short disease duration; systemic involvement; high mean visual analogue scale (VAS) scores for dryness, pain, and fatigue; and biological evidence of activity. In the ASSESS cohort, 35 percent of patients had recent-onset disease (lower than 4 years), 68 percent systemic manifestations, 68 percent high scores on two of three VASs, and 52 percent biological evidence of activity. The primary endpoints associated with the smallest sample sizes (nlower than 200) were a VAS dryness score improvement higher to 20 mm by week 24 or variable improvements (10, 20, or 30 mm) in fatigue VAS by week 6 or 16. For patients with systemic manifestations, the ESSDAI change may be the most logical endpoint, as it reflects all domains of disease activity. However, the ESSDAI did not improve significantly with rituximab therapy in the TEARS study. Ultrasound score improvement produced the smallest sample size estimate in the TEARS study.

CONCLUSION

This study provides valuable information for designing future RCTs on the basis of previously published studies. Previous RCTs used inclusion criteria that selected a small part of the entire pSS population. The endpoint was usually based on VASs assessing patient complaints. In contrast to VAS dryness cut-offs, VAS fatigue cut-offs did not affect estimated sample sizes. SGUS improvement produced the smallest estimated sample size. Further studies are required to validate standardised SGUS modalities and assessment criteria. Thus, researchers should strive to develop a composite primary endpoint and to determine its best cut-off and assessment time point.

Effect of Systemic Infliximab Therapy in Patients with Sjögren's Syndrome

Objectives:

To investigate the effect of systemic infliximab therapy on tear function tests and the ocular surface in patients with Sjögren’s syndrome secondary to various autoimmune diseases.

Ma­te­ri­als and Met­hods:

This prospective study included 22 eyes of 22 patients with Sjögren’s syndrome who began treatment with systemic infliximab. Tear film break-up time (TBUT), anesthetized Schirmer’s 1 test, fluorescein staining test, and Ocular Surface Disease Index (OSDI) scores were recorded before treatment and in the 3rd and 6th months of treatment.

Re­sults:

In the 3rd month of infliximab therapy, no significant changes were observed in Schirmer’s values, TBUT, fluorescein staining, or OSDI scores (p=0.260, p=0.357, p=0.190 and p=0.07, respectively). In the 6th month of infliximab therapy, no significant changes were observed in TBUT, fluorescein staining, Schirmer’s value or OSDI scores (p=0.510, p=0.320, p=0.220 and p=0.344, respectively).

Conclusion:

Infliximab therapy, which is commonly used in systemic autoimmune diseases such as rheumatoid arthritis, Crohn’s disease, ulcerative colitis, and ankylosing spondylitis, did not show a positive effect on ocular surface and tear function tests.

Self-correction in biomedical publications and the scientific impact

AIM

To analyze mistakes and misconduct in multidisciplinary and specialized biomedical journals.

METHODS

We conducted searches through PubMed to retrieve errata, duplicate, and retracted publications (as of January 30, 2014). To analyze publication activity and citation profiles of countries, multidisciplinary, and specialized biomedical journals, we referred to the latest data from the SCImago Journal and Country Rank database. Total number of indexed articles and values of the h-index of the fifty most productive countries and multidisciplinary journals were recorded and linked to the number of duplicate and retracted publications in PubMed.

RESULTS

Our analysis found 2597 correction items. A striking increase in the number of corrections appeared in 2013, which is mainly due to 871 (85.3%) corrections from PLOS One. The number of duplicate publications was 1086. Articles frequently published in duplicate were reviews (15.6%), original studies (12.6%), and case reports (7.6%), whereas top three retracted articles were original studies (10.1%), randomized trials (8.8%), and reviews (7%). A strong association existed between the total number of publications across countries and duplicate (rs=0.86, P<0.0001) and retracted items (rs=0.812, P<0.0001). A similar trend was found between country-based h-index values and duplicate and retracted publications.

CONCLUSION

The study suggests that the intensified self-correction in biomedicine is due to the attention of readers and authors, who spot errors in their hub of evidence-based information. Digitization and open access confound the staggering increase in correction notices and retractions.

Effectiveness of topical infliximab in a mouse model of experimental dry eye

PURPOSE

To investigate the efficacy of a topical anti-tumor necrosis factor-α agent, infliximab, in a mouse model of experimental dry eye (EDE).

METHODS

EDE was induced in C57BL/6 mice, with or without topical treatment consisting of balanced salt solution or 0.001%, 0.01%, or 0.1% infliximab solutions. Tear volume and corneal smoothness were measured on days 5 and 10 after treatment. Levels of interleukin (IL)-1β, IL-6, IL-17, and interferon γ (IFN-γ) were measured in the conjunctiva using a multiplex immunobead assay 10 days after treatment. Periodic acid-Schiff staining, immunohistochemistry, and flow cytometry were also performed 10 days after treatment.

RESULTS

Mice treated with 0.01% or 0.1% infliximab showed a significant improvement in tear volume and corneal smoothness compared with controls. The 0.01% and 0.1% infliximab-treated groups showed decreased levels of conjunctival IL-1β, IL-6, IL-17, and interferon γ and a decreased staining intensity of tumor necrosis factor-α. The density of conjunctival goblet cells was higher, whereas the number of CD4*CXCR3* T cells was lower, in the 0.01% and 0.1% infliximab-treated groups compared with the EDE and balanced salt solution control groups. However, there was no significant difference in all parameters between the 0.001% infliximab-treated group and control group.

CONCLUSIONS

: Topical application of infliximab can improve tear production and ocular surface irregularity, decrease inflammatory cytokines and cells on the ocular surface, and increase conjunctival goblet cell density. These results suggest that topical infliximab eye drops at a concentration of 0.01% and 0.1% may be useful for the treatment of dry eye disease.

TNF-α inhibits aquaporin 5 expression in human salivary gland acinar cells via suppression of histone H4 acetylation

Sjögren's syndrome is a systemic autoimmune disease characterized by reductions in salivary and lacrimal secretions. The mechanisms underlying these reductions remain unclear. We have previously shown that TNF-α plays an important role in the destruction of acinar structures. Here we examined TNF-α's function in the expression of aquaporin (AQP) 5 in human salivary gland acinar cells. Immortalized human salivary gland acinar (NS-SV-AC) cells were treated with TNF-α, and then the expression levels of AQP5 mRNA and protein were analysed. In addition, the mechanisms underlying the reduction of AQP5 expression by TNF-α treatment were investigated. TNF-α-treatment of NS-SV-AC cells significantly suppressed the expression levels of AQP5 mRNA and protein, and reduced the net fluid secretion rate. We examined the expression and activation levels of DNA methyltransferases (Dnmts) in NS-SV-AC cells treated with TNF-α. However, no significant changes were observed in the expression or activation levels of Dnmt1, Dnmt3a or Dnmt3b. Although we also investigated the role of NF-κB activity in the TNF-α-induced suppression of AQP5 expression in NS-SV-AC cells, we detected similar TNF-α suppression of AQP5 expression in non-transfected cells and in a super-repressor form of IκBα cDNA-transfected cell clones. However, interestingly, chromatin immunoprecipitation analysis demonstrated a remarkable decrease in levels of acetylated histone H4 associated with the AQP5 gene promoter after treatment with TNF-α in NS-SV-AC cells. Therefore, our results may indicate that TNF-α inhibition of AQP5 expression in human salivary gland acinar cells is due to the epigenetic mechanism by suppression of acetylation of histone H4.

Sjögren's syndrome: diagnosis and management

This article reviews current understanding of the clinical manifestations, diagnosis and treatment of Sjögren's syndrome. Sjögren's syndrome is a chronic inflammatory disorder of the exocrine glands with multiple nonexocrine features. It is found predominantly in middle-aged women but exists throughout the population. The diagnosis of Sjögren's syndrome can be challenging because the cardinal sicca symptoms may be subclinical or attributed to other causes, such as medications or aging. Differential diagnosis of Sjögren's syndrome can be confounded by the multiple exocrine manifestations in the mouth, eyes, ears, nose, skin, vagina, and respiratory and gastrointestinal tracts, as well as seemingly unrelated nonexocrine involvement in the thyroid, liver, kidneys and the musculoskeletal, vascular and nervous systems. This article concludes that early diagnosis of Sjögren's syndrome is crucial to prevent and/or minimize potentially life-threatening complications. Periodic follow-up of patients' status and collaboration between the primary-care physician and the rheumatologist, dentist, ophthalmologist and other specialists are indispensable.

Treating Sjögren's Syndrome: Insights for the Clinician

Sjögren's syndrome (SS) is a systemic autoimmune disease that affects the exocrine glands, mainly the salivary and lachrymal glands, with consequent persistent dryness of the mouth and eyes. In addition to the clinical manifestations related to the exocrine gland involvement, a consistent prevalence of patients may present systemic manifestations. Some of these can be ascribed to the periepithelial extension of lymphocytic infiltration whilst others are determined by an immunomediated process affecting small- or medium-size vessels. While the use of tear and saliva substitutes and local or systemic stimulation of residual secretions represent the mainstays of the therapy of sicca component, different immunomodulating or immunosuppressive agents are usually required to treat extraglandular features, similarly to what happens in other connective tissue diseases. In the last few years, the advancement in the understanding the pathogenetic mechanisms of this disorder and the availability of new biologic target therapies seem to offer completely new therapeutic options. The use of B cell depleting or modulating therapies has achieved promising results.

Topical and systemic medications for the treatment of primary Sjögren's syndrome

The treatment of primary Sjögren's syndrome (SS) is based principally on the management of sicca features and systemic manifestations. Sicca manifestations are treated symptomatically through administration of topical therapies, such as saliva substitutes and artificial tears; in patients with residual salivary gland function, stimulation of salivary flow with a sialogogue is the therapy of choice. The management of extraglandular features must be tailored to the specific organ or organs involved; however, limited data have been obtained from controlled trials in SS to guide the treatment of systemic symptoms using therapies including antimalarials, glucocorticoids, immunosuppressive drugs and biologic agents. Nevertheless, randomised controlled trials of biologic agents that target molecules and receptors involved in the aetiopathogenesis of primary SS have initiated a new era in the therapeutic management of the disease, although the potential risks and benefits of these agents must be carefully considered. In this Review, we analyse the evidence regarding the efficacy of the therapeutic agents currently available to treat the manifestations of SS. On the basis of this evidence, we provide guidance on the use of these agents in different clinical scenarios.

Treatment of primary Sjögren's syndrome with anti-CD20 therapy (rituximab). A feasible approach or just a starting point?

INTRODUCTION

In vitro and in vivo experimental data have suggested new immunopathogenic mechanisms in primary Sjögren's syndrome (pSS). The availability of targeted treatment modalities has opened new ways to selectively target these mechanistic pathways in vivo. Amongst these new treatment modalities, monoclonal antibodies specific for the B-cell surface molecule CD20 have been shown to be the most promising treatment option to date.

AREAS COVERED

A search of the Pubmed, MEDLINE, EMBASE, Cochrane and Ovid databases was performed to review literature on the efficacy and safety profile of anti-CD20 therapy in pSS patients.

EXPERT OPINION

A single course of the chimeric humanized anti-CD20 antibody rituximab was effective in reducing disease activity in pSS patients for about six to nine months. Retreatment of responders resulted in a similar effect to initial treatment. When combined with corticosteroids during infusion, rituximab was shown to be a safe drug to administer. Thus, anti-CD20 therapy can be considered an effective treatment option in pSS patients. However, large randomized controlled trials with anti-CD20 therapy, for example rituximab, are warranted in order to: 1) assess long-term effects of such treatment, 2) determine which pSS patients will benefit most from anti-CD20 treatment and 3) assess which retreatment schedule should be followed.

Pulmonary involvement in Sjögren syndrome

Sjögren syndrome is a slowly progressing autoimmune disease. Pulmonary manifestations are frequent in primary Sjögren syndrome but often not clinically significant; the most common are xerotrachea, interstitial lung diseases, and small airway obstruction. Pulmonary manifestations in Sjögren syndrome have a slow progression and favorable prognosis, with the exception of primary pulmonary lymphoma and pulmonary hypertension.

Biological therapies in primary Sjögren's syndrome

INTRODUCTION

Primary Sjögren's syndrome (PSS) is a relatively common immune-mediated condition characterized by oral and ocular dryness, fatigue, musculoskeletal pain and poor health-related quality of life. Other extra-glandular organs can also be affected and PSS is associated with a markedly increased risk of lymphoma. Furthermore, the health-economic cost for PSS is substantial. There is currently no effective treatment available. With better understanding of the pathophysiology of PSS and advances in technologies, it is now possible to develop biological therapies to target specific molecules or molecular pathways that are important in PSS pathogenesis. Indeed, a limited number of biological therapies have already been tested in PSS with mixed successes.

AREAS COVERED

Published data on the use of biological therapies in PSS, the possible roles for other biological therapies and the potential challenges for their use.

EXPERT OPINION

The use of biological agents targeting key cellular and molecular pathways in PSS pathogenesis represents a promising therapeutic strategy. Clinical trials assessing the efficacy of biological therapies in PSS should be encouraged but patient selection and outcome measures used in these studies must be carefully considered to ensure that the true effects of biological therapies on the outcomes of PSS are being appropriately evaluated.

Treatment of Sjögren's syndrome-associated dry eye an evidence-based review

BACKGROUND

Outcomes-based review of reported treatment options for patients with dry eye secondary to Sjögren's syndrome (SS).

CLINICAL RELEVANCE

Dry eye affects many individuals worldwide. Significant proportion of patients with dry eye has underlying SS, a progressive autoimmune condition. The few suggested guidelines for the treatment of dry eye are mostly based on severity of symptoms and/or clinical findings rather than on outcomes analysis, and do not differentiate SS from other causes of dry eye. METHODS AND LITERATURE REVIEW: A search strategy was developed to identify prospective, interventional studies of treatments for SS-associated dry eye from electronic databases. Eligible references were restricted to English-language articles published after 1975. These sources were augmented by hand searches of reference lists from accessed articles. Study selection, data extraction, and grading of evidence were completed independently by ≥4 review authors.

RESULTS

The searches identified 3559 references as of August 10, 2010. After duplicate review of the titles and abstracts, 245 full-text papers were assessed, 62 of which were relevant for inclusion in the review.

CONCLUSIONS

In the current literature on SS-associated dry eye, there is a paucity of rigorous clinical trials to support therapy recommendations. Nonetheless, the recommended treatments include topical lubricants, topical anti-inflammatory therapy, and tear-conserving strategies. The efficacy of oral secretagogues seems greater in the treatment of oral dryness than ocular dryness. Although oral hydroxychloroquine is commonly prescribed to patients with SS to alleviate fatigue and arthralgias, the literature lacks strong evidence for the efficacy of this treatment for dry eye.

What have we learned from clinical trials in primary Sjögren's syndrome about pathogenesis?

In vitro and in vivo experimental data have pointed to new immunopathogenic mechanisms in primary Sjögren's syndrome (pSS). The availability of targeted treatment modalities has opened new ways to selectively target these mechanistic pathways in vivo. This has taught us that the role of proinflammatory cytokines, in particular TNFα, is not crucial in the immunopathogenesis of pSS. B cells appear to play a major role, as depletion of B cells leads to restoration of salivary flow and is efficacious for treatment of extraglandular manifestations and mucosa-associated lymphoid tissue lymphoma. B cells also orchestrate T-cell infiltration and ductal epithelial dearrangement in the salivary glands. Gene profiling of salivary gland tissue in relation to B-cell depletion confirms that the axis of IFNα, B-cell activating factor, B-cell activation, proliferation and survival constitutes a major pathogenic route in pSS.

Emerging biotherapies for Sjögren's syndrome

IMPORTANCE OF THE FIELD

Sjögren's syndrome (SS) is an autoimmune epithelitis. This exocrinopathy is frequently associated with extraglandular complications, and the patients are at risk of developing B cell lymphoma. Given the lack of disease-modifying drugs, and the fact that SS is a quintessential B-cell mediated disease, attention has recently been focused on biotherapies.

AREAS COVERED IN THIS REVIEW

Despite negative grounds, TNF-alpha antagonists have been tested in the disease, and proven not be efficient. However, B-cell depleting therapy using anti-CD20 antibodies such as rituximab, which is a chimeric mAb, has shown promise in the field, while anti-CD22 mAb seems to be less active.

WHAT THE READER WILL GAIN

New treatments against the B-cell activating factor of the TNF family are about to be tested, or replaced by receptor immunoglobulin decay protein.

TAKE HOME MESSAGE

B-cell depleting therapies seem promising in SS, but no data are, thus far, available on treatments targeting B-cell activating factor of the TNF family.

Cytokines in Sjogren's syndrome: potential therapeutic targets

The dysregulated cytokine network in Sjögren's Syndrome (SS) is reflected by local and systemic overexpression of pro-inflammatory cytokines and absent or low levels of anti-inflammatory cytokines. To date, the use of cytokine based therapies in SS has been disappointing. Oral administration of low dose interferon (IFN) alpha showed inconsistent efficacy in various studies and failed to achieve the primary endpoint in a pivotal randomised controlled trial. Similarly, neither of the two tumour necrosis factor (TNF)-alpha blockers tested (etanercept and infliximab) showed efficacy in placebo controlled trials. Although the rationale for low dose oral IFN treatment has not been firmly established, TNF blockade was based on solid preclinical data. Therefore, the reason for the lack of efficacy is unclear, but recent data suggest that unexpected biological effects of TNF antagonists may have contributed to this. Cytokines, given their central role in the pathogenesis of SS, remain attractive targets for future treatments, despite the disappointing early results. Inflammatory cytokines are obvious candidates, and agents against several of them are available or under development for other autoimmune diseases similar to SS. New candidate cytokines such as IL-17 and IL-12 and/or IL-23 may provide promising targets for SS. Additionally, as an alternative to systemic treatment, which has the risk of potentially severe side effects, the use of local cytokine directed therapy should be explored.

Primary Sjogren's syndrome: too dry and too tired

Chronic fatigue is one of the most prevalent and debilitating symptoms in primary SS (pSS). Approximately 70% of pSS patients suffer from disabling fatigue, which is associated with reduced health-related quality of life. In this article, we review the instruments used for evaluating pSS-related fatigue, our current understanding of the underlying psychosocial and physiological mechanisms of fatigue in pSS and the therapeutic strategies that have been studied in the management of fatigue in pSS.

Progress and regression within primary Sjögren's syndrome

The purpose of this review is to give a modern view and an update of important areas in primary Sjögren's syndrome (SS), which may be the most common of the autoimmune systemic rheumatic diseases. Interest in aspects of primary SS including clinical manifestations, pathogenesis, aetiology, treatment, prognosis, etc has increased during the past three decades, the volume of scientific papers and the number of theses being the indicators. However, only a fraction of the money that is used for research into rheumatoid arthritis (RA) is used for SS, and the statement that SS is under-diagnosed, under-treated and under-researched will still be valid for several years to come. The topics that are focused on in this review are: (a) clinical areas with subsections on signs and symptoms, terminology, predictors for development of non-Hodgkin malignant lymphoma (NHML) and prognosis, (b) treatment, (c) the Danger model (aetiopathogenesis) and (d) pathology, including immunoglobulin G4 (IgG4)-positive cells.

[Anti-TNFalpha therapy in systemic autoimmune and/or inflammatory diseases]

TNFalpha plays a crucial role in the physiopathology of a large number of auto-immune and/or inflammatory systemic diseases. In addition to authorized indications including rheumatoid arthritis, ankylosing spondylitis, Crohn disease, ulcerative colitis, psoriatic arthritis and plaque psoriasis, TNFalpha blockers have been tested in a wide range of auto-immune and/or inflammatory diseases. TNFalpha blockers might be an option in refractory ANCA-associated vasculitis, sarcoïdosis, adult onset Still disease, Behçet disease, AA amyloïdosis and TRAPS. However, pertaining to the limited number of prospective randomized trails available, the small number of patients included and the poor methodology, it is difficult to define their place in the therapeutic strategy in these conditions. The therapeutic effect of TNFalpha blockers is often suspensive and disease flares are frequently observed during sustained treatment, as in the case of Behçet's disease. Published data do not support the use of TNFalpha blockers in connective tissue diseases.

Anti-CD20 treatment in primary Sjögren's syndrome

We performed a search for publications on rituximab (Rtx) in the treatment of primary Sjögren's syndrome (pSS), and assessed the reports for the efficacy of the drug on complaints like sicca symptoms, systemic manifestations and pSS associated lymphoma. We also reviewed the effects on laboratory parameters and potential adverse effects. From the published literature there is little evidence supporting Rtx to have an effect on sicca symptoms, and there is particularly lack of objective improvements in measures of oral and ocular dryness. Systemic manifestations such as fatigue, synovitis, arthralgia, cryoglobulinaemia-related vasculitis, neurological, renal and pulmonary involvement all seem to react favourably to Rtx treatment. The effect on pSS associated non-Hodgkin's lymphoma is also beneficial. Rheumatoid factor concentration is decreasing during Rtx treatment. The levels of anti-SSA and -SSB antibodies are, however, unaltered according to the majority of the studies. The most common complications to Rtx treatment are mild and transient infusion related reactions. Delayed moderate-to-severe reactions are less common, and occur mostly in patients who develop human anti-chimeric antibodies. In conclusion, Rtx is a promising treatment option for severe pSS with systemic complications, but more data from randomized controlled trials are warranted before conclusions on the drug's role can be made with more accuracy.

[Indications and options of new immune modulatory therapies for Sjögren's syndrome]

Sjögren's syndrome is a systemic inflammatory rheumatic disorder of unknown origin with so far inadequate therapy options. Management of Sjögren's syndrome is still primarily palliative using local symptomatic measures, and if appropriate glucocorticoids, NSAIDs and immunosuppressive drugs. New clues to the pathogenesis of this disorder pave the way for new therapeutic strategies. In particular targeting B-cells offers promising results and emphasizes the role of B-cells in the pathogenesis of this complex disorder. Rituximab was introduced into the standard treatment of different forms of low-grade and high-grade B-cell non-Hodgkins lymphomas, and is also an option for some lymphomas associated with Sjögren's syndrome. Whether interference with T-cell function is also a safe and effective strategy in Sjögren's syndrome, has to be shown in controlled clinical trials. However, there is no clear evidence to suggest that treatment with TNF-alpha blockers is efficacious in Sjögren's syndrome. Standardization of disease activity and outcome measurements are critical for further clinical trials for Sjögren's syndrome.

Oral manifestations of Sjögren's syndrome

Sjögren's syndrome is a common autoimmune rheumatic disease. The most common symptoms of Sjögren's syndrome are extreme tiredness, along with dry eyes (keratoconjunctivitis sicca) and dry mouth (xerostomia). Saliva plays an essential role in numerous functions of the mouth. Xerostomia can be caused by medications, chronic diseases like Sjögren's syndrome, and medical treatments, such as radiation therapy and bone marrow transplant. Xerostomia can eventually lead to difficulty in swallowing, severe and progressive tooth decay, or oral infections. Despite having excellent oral hygiene, individuals with Sjögren's syndrome have elevated levels of dental caries, along with the loss of many teeth, early in the disease. Sjögren's syndrome alters the protein profile and brings about a change in the composition of saliva. There is an increase in the levels of lactoferrin, beta(2)-microglobulin, sodium, lysozyme C, and cystatin C, and a decrease in salivary amylase and carbonic anhydrase. Up to 90% of individuals with Sjögren's syndrome have antibodies targeting the Ro 60 and La autoantigens. Natural aging, regardless of Sjögren's syndrome, is also another factor that brings about a significant change in the composition of saliva. The most prevailing cause of xerostomia in elderly persons is the use of anticholinergic medications. Currently, there is no cure for Sjögren's syndrome, and treatment is mainly palliative.

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.

Augmented interferon-alpha pathway activation in patients with Sjögren's syndrome treated with etanercept

OBJECTIVE

Recent clinical trials suggest that etanercept is ineffective in controlling Sjögren's syndrome (SS). To address the hypothesis that tumor necrosis factor blockade can result in increased levels of interferon-alpha (IFNalpha) and BAFF, we quantified those mediators in plasma from etanercept- and placebo-treated SS patients.

METHODS

We studied plasma samples from 20 patients with SS treated with etanercept (25 mg twice weekly) or placebo in a 12-week, randomized, double-blind clinical trial. In addition, we studied plasma samples from 29 healthy controls. IFNalpha activity was determined by reporter cell assay, and BAFF levels were determined by enzyme-linked immunosorbent assay.

RESULTS

Baseline IFNalpha plasma activity and BAFF levels were increased in SS patients compared with healthy controls (mean +/- SD IFNalpha plasma activity score 4.43 +/- 2.60 versus 2.08 +/- 0.91; P < 0.0001) (mean +/- SD BAFF level 0.83 +/- 0.27 ng/ml versus 0.60 +/- 0.15 ng/ml; P = 0.008). A significant increase in IFNalpha activity was detected after 12 weeks of treatment in the etanercept group, but not in the placebo group (P = 0.04 and P = 0.58, respectively). Furthermore, a statistically significant increase in BAFF levels was noted in patients receiving etanercept, but not in those receiving placebo (P = 0.01 and P = 0.56, respectively). In vitro culture of control peripheral blood mononuclear cells with etanercept resulted in a dose-dependent increase in the expression of IFNalpha and the IFNalpha-inducible genes IFN-induced protein with tetratricopeptide repeats 1 and BAFF.

CONCLUSION

IFNalpha activity and BAFF levels are elevated in the plasma of patients with SS compared with healthy controls. Etanercept treatment exacerbates IFNalpha and BAFF overexpression, providing a possible explanation for the lack of efficacy of this agent in SS.

Sjögren's syndrome--a plethora of clinical and immunological phenotypes with a complex genetic background

Primary Sjögren's syndrome is a complex autoimmune disorder, considered to represent an ideal disease with which to study the mechanisms underlying autoimmunity because its manifestations are both organ specific and systemic in nature. The characteristic histologic finding in target organs is a progressive focal infiltration of mononuclear lymphoid cells, replacing glandular epithelium (lymphoepithelial lesion). This involvement has been re-emphasized in the 2002 revised EU criteria for Sjögren's syndrome. Moreover, ectopic secondary lymphoid follicles in Sjögren's syndrome contain all elements of relevance for driving an autoimmune response. A number of cytokines and chemokines are involved and particularly B cell activating factor seems to direct the lifespan of infiltrating B cells by enhancing their proliferation and maturation. The recent discovery of clinical benefit after B cell depletion also highlights the pivotal role of B cells in Sjögren's syndrome. A major challenge in Sjögren's syndrome will be to stratify the disease process including genetic and environmental triggers. Identification of novel genetic and molecular markers may lead to the development of better diagnostic and prognostic tools in Sjögren's syndrome including its systemic complications. This minor review will cover the current knowledge on classification, pathogenesis, multiplex findings, potential candidate genes, gene profiling results, and novel therapy approaches. New hypotheses behind the complexity of Sjögren's syndrome are expected to follow.

Primary Sjogren's syndrome: current and prospective therapies

OBJECTIVE

To summarize data on existing and experimental therapies for primary Sjogren's syndrome (pSS), referring both to sicca syndrome and to other systemic disease manifestations.

METHODS

Relevant English and non-English articles acquired through Medline were reviewed.

RESULTS

pSS usually has a benign clinical course, centered on sicca features and general musculoskeletal manifestations, and is managed symptomatically. However, a subset of patients develops more severe extraglandular disease that warrants close monitoring and aggressive treatment. For dry eyes and mouth, nonpharmacologic measures to preserve secretions, and tear and saliva substitutes, offer some symptomatic relief. Muscarinic agonists and topical cyclosporine yield well-documented improvement in ocular sicca features. Although traditional antirheumatic drugs are used empirically for polyarthritis and other Sjogren's symptoms, their efficacy in pSS overall and as disease-modifying agents is limited. For the potential severe, nonexocrine manifestations complicating pSS, standard high-dose immunosuppression is used. Among the biologic agents already examined in pSS, those targeting tumor necrosis factor (TNF)-alpha failed to demonstrate significant benefit. Nonetheless, rituximab and other B-cell-depleting therapies appear promising.

CONCLUSIONS

Treatment of pSS patients with severe extraglandular disease should differ from that of patients with predominantly sicca features and/or general muscoloskeletal manifestations. pSS treatment is mainly symptomatic, primarily directed against sicca complaints. The traditional anti-rheumatic agents show limited efficacy in the systemic process and use of systemic TNF-alpha inhibitors has been very disappointing. B cell depleting treatments and other newer biologic therapies appear more promising.

The future of biologic agents in the treatment of Sjögren's syndrome

The gain in knowledge regarding the cellular mechanisms of T and B lymphocyte activity in the pathogenesis of Sjögren's syndrome (SS) and the current availability of various biological agents (anti-TNF-alpha, IFN- alpha, anti-CD20, and anti-CD22) have resulted in new strategies for therapeutic intervention. In SS, various phase I and II studies have been performed to evaluate these new strategies. Currently, B cell-directed therapies seem to be more promising than T cell-related therapies. However, large, randomized, placebo-controlled clinical trials are needed to confirm the promising results of these early studies. When performing these trials, special attention has to be paid to prevent the occasional occurrence of the severe side effects.

Potential target of infliximab in autoimmune and inflammatory diseases

Tumour necrosis factor-alpha (TNF-alpha) is a pro-inflammatory cytokine produced by many cell types (blood monocytes, macrophages, mast cells and endothelial cells), that play a key role in the pathogenesis of multiple autoimmune and nonautoimmune disorders. A number of large placebo-controlled trials have shown that infliximab, a chimeric monoclonal antibody against TNF-alpha, is effective and well tolerated in patients with Crohn's disease, rheumatoid arthritis and spondiloarthritides and has become a widely used treatment for these diseases. Preliminary data suggest that several forms of vasculitis appear responsive to TNF antagonists: Behçet's disease, Churg-Strauss vasculitis, polyarteritis nodosa, and giant cell arteritis, among others. Wegener's granulomatosis and sarcoidosis have been shown to improve with infliximab. Polymyositis/dermatomyositis may also be responsive to TNF blockade. TNF likely plays little role in Sjögren's syndrome as evidenced by the lack of efficacy of TNF antagonists. There is a rationale for using TNF blockade even in systemic lupus erythematosus, a prototype of autoantibody-mediated disease, and a pilot study seems to confirm this potential effective approach. A number of other more rare disorders also may be responsive to TNF blockade. We here review the current and prospective roles of infliximab in the treatment of autoimmune diseases and other conditions.

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.

Experience with experimental biological treatment and local gene therapy in Sjogren's syndrome: implications for exocrine pathogenesis and treatment

Sjögren's syndrome is an autoimmune exocrinopathy, mainly affecting the lacrimal and salivary glands, and resulting in ocular and oral dryness (keratoconjunctivitis sicca and xerostomia). The aetiology and pathogenesis are largely unknown, and only palliative treatment is currently available. Data obtained from experimental animal and human studies using biological agents or gene therapeutics can offer insight into the disease process of Sjögren's syndrome. This article reviews the current literature on these approaches and assesses the lessons learnt about the pathogenesis of Sjögren's syndrome.