Effects of preceding sialadenitis on the development of autoimmunity against salivary gland.

OBJECTIVE: The mechanism underlying the onset and development of autoimmune diseases such as Sjogren's syndrome is not well understood. Here, we examined the effects of preceding inflammation of the salivary gland at the onset of autoimmunity against the salivary gland. MATERIALS AND METHODS: One side of the submandibular gland duct was ligated in mice and the effect on the contralateral gland was investigated. After histological evaluation with hematoxylin and eosin staining, the presence of autoantibodies and immune compounds was examined. RESULTS: In all five strains of mice that were used, the salivary gland of the ligated side showed severe inflammation and atrophic change. In two mouse strains (SJL/J and PL/J), mild sialadenitis was observed on the non-ligated side 8 weeks after ligation. Autoantibodies reacting to the salivary gland were detected in three mouse strains (C3H/He, SJL/J, and PL/J). Immune complex was also detected in the duct basement membrane. CONCLUSION: The results indicate that the autoimmune mechanism is activated by the transient inflammation in the salivary gland under a specific genetic background.