Sjögren’s syndrome is an autoimmune disease that affects over 2 million Americans, primarily over the age of 40. One of the major outcomes of Sjögren's syndrome is xerostomia (dry mouth) that is caused by immune system attack on moisture producing salivary glands. Researchers at the National Institute of Dental and Craniofacial Research have developed a therapy that alleviates xerostomia in a murine model of Sjögren's syndrome. This technology consists of a local delivery of adeno-associated virus (AAV) mediated cytotoxic T-lymphocyte antigen 4 Immunoglobulin-G (CTLA4IgG) fusion protein to salivary glands. The system effectively blocks CTLA4 ligand interactions with T cell surface receptors, resulting in immune suppression and reversal of autoimmune-related xerostomia. Targeted delivery of the AAV-CTLA4-IgG system makes this invention a novel therapeutic for the prevention of xerostomia-associated pain and discomfort caused by Sjögren's syndrome.