Abstract
Primary Sjögren's syndrome (pSS) is a chronic inflammatory autoimmune disease of exocrine gland. In pSS, permanent activation of the adaptive immune system is obvious. Lymphocyte co-stimulation plays an important part in inflammation and immunotherapy. Co-stimulator ligands (B7-H2) are significant costimulatory molecules. The interaction of B7-H2, with its sole receptor ICOS, promotes T cell differentiation, effector responses and activation. Our study found that B7-H2 is up-regulated in salivary gland, saliva and serum of pSS patients. B7-H2 expression in saliva have negatively correlated with saliva weight. Overexpression of B7-H2 into human salivary gland epithelial (HSGE) cells, increased the activity of p65 (phosphorylated at S536) and decreased the expression of AQP5. Furthermore, up-regulated B7-H2 induced apoptosis and inhibited proliferation in HSGE cell lines. These results suggest the expression of B7-H2 can decrease the secretion of saliva, increase the quantity of dental caries and reduce lifespan of patients of pSS.
B7-H3 participates in human salivary gland epithelial cells apoptosis through NF-κB pathway in primary Sjögren’s syndrome