Defective cellular trafficking of lacrimal gland aquaporin-5 in Sjögrenʹs syndrome

Dry eyes and dry mouth are clinical hallmarks of Sjögrenʹs syndrome. We assessed the distribution of a quaporin-5, ry eyes and dry mouth are clinical hallmarks of Sjögrenʹs syndrome. We assessed the distribution of a quaporin-5 (AQP5) in lacrimal gland biopsy samples. Healthy controls and patients with Mikuliczʹs disease or non-Sjögrenʹs syndrome dry eye had the expected apical distribution of AQP5 in lacrimal acinar cells. By contrast, cytoplasmic AQP5 was seen in patients with Sjögrenʹs syndrome. Sodium channel and sodium-potassium ATPase distributions were normal in all groups. These findings show a selective defect in lacrimal gland AQP5 trafficking in Sjögrenʹs syndrome that might contribute to decreased lacrimation and dry eye in these patients. (AQP5) in lacrimal gland biopsy samples. Healthy controls and patients with Mikuliczʹs disease or non-Sjögrenʹs syndrome dry eye had the expected apical distribution of AQP5 in lacrimal acinar cells. By contrast, cytoplasmic AQP5 was seen in patients with Sjögrenʹs syndrome. Sodium channel and sodium-potassium ATPase distributions were normal in all groups. These findings show a selective defect in lacrimal gland AQP5 trafficking in Sjögrenʹs syndrome that might contribute to decreased lacrimation and dry eye in these patients.