Characterization of Extracellular Vesicle Cargo in Sjögren’s Syndrome through a SWATH-MS Proteomics Approach

Abstract

Primary Sjögren’s syndrome (pSS) is a complex heterogeneous disease characterized by a wide spectrum of glandular and extra-glandular manifestations. In this pilot study, a SWATH-MS approach was used to monitor extracellular vesicles-enriched saliva (EVs) sub-proteome in pSS patients, to compare it with whole saliva (WS) proteome, and assess differential expressed proteins between pSS and healthy control EVs samples. Comparison between EVs and WS led to the characterization of compartment-specific proteins with a moderate degree of overlap. A total of 290 proteins were identified and quantified in EVs from healthy and pSS patients. Among those, 121 proteins were found to be differentially expressed in pSS, 82% were found to be upregulated, and 18% downregulated in pSS samples. The most representative functional pathways associated to the protein networks were related to immune-innate response, including several members of S100 protein family, annexin A2, resistin, serpin peptidase inhibitors, azurocidin, and CD14 monocyte differentiation antigen. Our results highlight the usefulness of EVs for the discovery of novel salivary-omic biomarkers and open novel perspectives in pSS for the identification of proteins of clinical relevance that could be used not only for the disease diagnosis but also to improve patients’ stratification and treatment-monitoring. Data are available via ProteomeXchange with identifier PXD025649.

Impact of the Glycemic Level on the Salivary Proteome of Middle-Aged and Elderly People With Type 2 Diabetes Mellitus: An Observational Study

“…explored the potential of salivary proteomics to identify primary Sjögren's syndrome by applying LC-SWATH-MS technology (Cecchettini et al, 2019;Finamore et al, 2021). In our study, we used LC-MS/MS relying on the DIA method to test the subjects' saliva to ensure the accuracy and coverage of protein quantification and identification.…”

Salivary Trefoil Factor Family (TFF) Peptides and Their Roles in Oral and Esophageal Protection: Therapeutic Potential

“…Within the last two decades, the saliva proteome was subjected to a huge number of investigations, which often focused on highly specific aspects, such as certain diseases (also use of saliva as diagnostic fluid) and response to different stimuli, such as psychological stress ("stimulated saliva") [6][7][8]. Recently, not only whole saliva was investigated, but also extra-vesicles-enriched saliva, which contains exosomes, i.e., extracellular vesicles, which probably originate from intracellular multivesicular bodies [9]. In normal saliva, more than 3000 proteins were identified with a relative abundance spanning about 14 orders of magnitude [6].…”

“…), but it also has to provide the necessary water by aquaporins (water channels) [1,2,4,5,14]. The importance of a functional salivary flow can be estimated from patients with a catastrophic loss of salivary function, such as patients with radiation therapy because of head and neck cancers, patients with congenital absence of salivary glands, and patients with Sjögren's syndrome [3,4,9]. Thus, there is still a need for the development for better formulations of saliva substitutes, particularly with strongly improved antimicrobial properties (see Section 3.2).…”

The Involvement of Alarmins in the Pathogenesis of Sjögren’s Syndrome

“…These findings indicate that, in addition to contributing to the pathophysiology of SS, annexin probably also plays an important role in the progression of pSS to pSS/MALT [ 186 ]. Increased levels of annexin-A2 were also observed in pSS saliva sub-proteome, suggesting that saliva might be used as a potential indicator for disease progression and lympho-proliferation in patients with pSS [ 187 ] ( Figure 3 ).…”