STING is a key endoplasmic reticulum protein in innate immunity that detects cytoplasmic DNA and activates type I interferon synthesis and secretion of proinflammatory mediators. It participates in the regulation of antiviral and antibacterial immune responses in vivo. In the salivary glands of C57BL/6 mice, STING is mainly expressed in ductal and stromal cells. In vitro studies have shown that DMXAA activates the STING pathway and induces IFN-β production in primary salivary gland cells. In patients with primary Sjögren's syndrome (pSS), monocytes in the salivary glands are hyperresponsive to STING stimulation, resulting in increased numbers of IFN-α-producing monocytes. In the salivary gland tissue of SS patients, mtDNA binds cGAS, which activates the STING cascade, NF-κB, and the type I IFN immune response, increasing the expression of inflammatory mediators such as IFN-α, IL-8, IL-6, IFN-β, and TNF-α.