Sjögren’s syndrome (SS) is a heterogeneous autoimmune disease possessing both organ-specific and systemic features and encompassing a wide spectrum of clinical/serological abnormalities and scattered complications. While Sjögren’s syndrome is one of the most common autoimmune diseases in adults, SS is greatly underrecognized in clinical practice, mostly due to diverse symptomatic expressions making the initial diagnosis difficult. It is estimated that the disease remains undiagnosed in more than half of affected adults. While currently there is no cure for SS, results from recent clinical studies with rituximab for patients with primary SS and severe systemic complications were promising; this underlines the importance of early diagnosis to identify SS patients before irreversible damage to the affected organs and tissues occur.

The symptoms of SS can progress slowly and often are highly variable in presentation which makes the diagnosis difficult and challenging. There is a huge gap between the SS patient’s description of their symptoms and the objective findings. Unfortunately, the nature of sicca symptoms (dry eye and dry mouth) is very nonspecific, especially in the immediate absence of other SS-related complaints or findings. When SS is suspected in a patient with thorough evaluation of sicca symptoms, an objective test will be very useful to help the physician make the correct diagnosis of SS.

The aim/scope of this special issue is to understand the etiology and pathogenesis of SS based on animal models. The clinical presentation of SS patients including signs, symptoms, and biomarkers will be studies for better stratification of the disease, which not only helps in better and proper diagnosis but also helps in early therapeutic intervention. This issue will address the traditional and novel biomarkers that are specific and sensitive for diagnosis of SS. Methodology of diagnosis including other body fluids besides serum, like saliva, will also be addressed.

Potential topics include but are not limited to the following:

• Etiology and pathogenesis based on novel and/or established mouse models of SS
• Biomarkers for the early diagnosis of SS
• Stratification of SS and possible subtypes based on clinical presentation and biomarkers
• Novel platform for detecting Abs/biomarkers in different biofluids in SS
• Clinical validation of recently identified Abs/biomarkers in SS
• Clinical validation of noninvasive technologies for the diagnosis of SS
• Companion diagnostic biomarkers for monitoring the disease progress/activity of SS
• Biomarkers to distinguish SS from autoimmune dry eye
• Biomarkers to distinguish SS from autoimmune dry mouth
• Novel therapeutic target/strategy for the treatment of SS at different stages