Receptor of advanced glycation end product (RAGE) expression in the minor salivary glands of patients with Sjögren's syndrome: A preliminary study

Objective: Receptor for advanced glycation end product (RAGE) is a cell-surface receptor with ligands capable of inducing proinflammatory responses in autoimmunity. We investigated the immunohistochemical expression and immunoblotting of RAGE in labial salivary glands from Sjögren's syndrome (SS) patients. Material and methods: Ten minor salivary glands from SS and 15 from normal salivary tissue adjacent to mucocele were stained immunohistochemically using an antibody to RAGE. Immunoblotting was performed on four SS biopsies and four controls from normal gland. Results: Immunohistochemistry showed all sections positive for RAGE. The SS sections did not statistically differ from controls. In immunoblotting, SS samples expressed approximately 100% more RAGE than controls [probability (p) < 0.03, Student's t-test]. Conclusions: RAGE is present in the labial salivary glands of both normal and SS patients, with preliminary data suggesting over-expression in SS tissues. The role of RAGE in the pathogenesis of SS has yet to be determined.