Aberrant expression of the innate restriction factor bone marrow stromal antigen-2 in primary Sjögren's syndrome

Novel Diagnostic Biomarker BST2 Identified by Integrated Transcriptomics Promotes the Development of Endometriosis via the TNF-α/NF-κB Signaling Pathway

Endometriosis (EMS) is a common gynecological condition with apparent heterogeneity, lack of diagnostic markers, and unclear pathogenesis. A series of bioinformatics methods were employed to explore EMS's pathological mechanisms and potential biomarkers by analyzing the combined datasets of EMS (GSE7305, GSE7307, GSE58198, E-MTAB-694), which included 34 normal, 127 eutopic, and 46 ectopic endometrium samples. Then, wet-laboratory experiments (including Western blot, qRT-PCR, and Immunohistochemistry, Immunofluorescence, CCK-8, EdU, Wound healing, Transwell, and Adhesion assays) were applied to examine the biomarkers' expression and function in primary endometrial stromal cells. Bioinformatic analysis indicated that the core pathogenesis of EMS was dysregulated immune-inflammation and tissue remolding processes. Among the upregulated DEGs, BST2 was screened as a potential diagnostic biomarker in EMS, which associated with the revised American Fertility Society (r-AFS) stage and immune-inflammation processes of EMS. Moreover, BST2's overexpression was affirmed in the RNA and protein levels in EMS tissues. In vitro experiments demonstrated that TNF-α promoted the expression of BST2 in ESCs. And BST2 knockdown inhibited migration, invasion, adhesion, and inflammation except for the proliferation of ESCs, probably via the TNF-α/NF-κB pathway. Through a combination of wet and dry studies, we concluded that the core pathogenesis of endometriosis was dysregulated immune-inflammation and tissue remolding, and BST2 might be a potential diagnostic and therapeutic target in endometriosis.

Differentially Expressed Gene Pathways in the Conjunctiva of Sjögren Syndrome Keratoconjunctivitis Sicca

Sjögren syndrome (SS) is an autoimmune condition that targets the salivary and lacrimal glands, with cardinal clinical signs of dry eye (keratoconjunctivitis sicca, KCS) and dry mouth. The conjunctiva of SS patients is often infiltrated by immune cells that participate in the induction and maintenance of local inflammation. The purpose of this study was to investigate immune-related molecular pathways activated in the conjunctiva of SS patients. Female SS patients (n=7) and controls (n=19) completed a series of oral, ocular surface exams. Symptom severity scores were evaluated using validated questionnaires (OSDI and SANDE). All patients fulfilled the ACR/EULAR criteria for SS and the criteria for KCS. Fluorescein and lissamine green dye staining evaluated tear-break-up time (TBUT), corneal and conjunctival disease, respectively. Impression cytology of the temporal bulbar conjunctiva was performed to collect cells lysed and subjected to gene expression analysis using the NanoString Immunology Panel. 53/594 differentially expressed genes (DEGs) were observed between SS and healthy controls; 49 DEGs were upregulated, and 4 were downregulated (TRAF5, TGFBI, KLRAP1, and CMKLRI). The top 10 DEGs in descending order were BST2, IFITM1, LAMP3, CXCL1, IL19, CFB, LY96, MX1, IL4R, CDKN1A. Twenty pathways had a global significance score greater or equal to 2. Spearman correlations showed that 29/49 upregulated DEGs correlated with either TBUT (inverse) or OSDI or conjunctival staining score (positive correlations). Venn diagrams identified that 26/29 DEGs correlated with TBUT, 5/26 DEGs correlated with OSDI, and 16/26 correlated with conjunctival staining scores. Five upregulated DEGs (CFB, CFI, IL1R1, IL2RG, IL4R) were uniquely negatively correlated with TBUT. These data indicate that the conjunctiva of SS patients exhibits a phenotype of immune activation, although some genes could be inhibitory. Some of the DEGs and pathways overlap with previous DEGs in salivary gland biopsies, but new DEGs were identified, and some of these correlated with symptoms and signs of dry eye. Our results indicate that gene analysis of conjunctiva imprints is a powerful tool to understand the pathogenesis of SS and develop new therapeutic targets.

BST-2/Tetherin is involved in BAFF-enhanced proliferation and survival via canonical NF-κB signaling in neoplastic B-lymphoid cells

The development of Sjögren's syndrome (SS) is accompanied by B cell hyperproliferation and mutation. Our previous study identified aberrant expression of BST-2 (also known as Tetherin/CD317) in B cells from either the peripheral blood or infiltrated salivary glands. However, the roles of BST-2 in the regulation of B cell activation remain unknown. In this study, we identified that BST-2 can respond to BAFF simulation but not to other B cell simulators in neoplastic B cell lines. A CCK-8 assay, an EdU assay and Annexin V/PI staining indicated that BST-2 inhibition attenuated BAFF-enhanced proliferation and survival in both Raji cells and Daudi cells. Screening of BAFF-related signaling in neoplastic B-lymphoid cells indicated that BST-2 was involved in the regulation of NF-κB signaling upon BAFF simulation. However, inhibition of NF-κB by JSH-23 significantly reduced the proliferation and survival of Raji and Daudi cells under both normal and BAFF-simulated conditions. Collectively, our results indicate that BST-2/Tetherin is a BAFF-responsive membrane factor involved in the regulation of NF-κB signaling, thereby assisting in the proliferation and survival of neoplastic B-lymphoid cells. Our study provides a potential molecular mechanism underlying aberrant overactivation of B cells upon SS development.