Production of experimental autoimmune sialadenitis in mice immunized with homologous salivary gland extract and Klebsiella O3 lipopolysaccharide

An experimental murine model for autoimmune sialadenitis was produced by re peated immunization of homologous salivary gland extract together with Kleb siella O3 lipopolysaccharides as an immunological adjuvant. The cell infilt ration was observed in the salivary glands of mice immunized more than twic e, inflammatory cells consisting mainly of CD4+ T cells and CD8+ T cells ac cumulated at the perivascular regions. There was hyperplasia and enlargemen t of ductal epithelial cells in the secretory acinar units in salivary glan ds of repeatedly immunized mice. The repeated immunization developed delaye d-type hypersensitivity and autoantibody production to the homologous saliv ary gland extract. The immunohistochemical analysis showed positive stainin g on the cuboidal cells in the intercalated ducts, and the columnar pseudos tratified cells in the striated ducts. Organ-specific antigens with molecul ar weights ranging from 20 to 90 kDa were recognized by the sera from immun ized mice. Therefore, it was suggested that the sialadenitis was produced b y the autoimmune mechanism and might be a new experimental model for charac terization of the pathogenesis of autoimmune sialadenitis. (C) 2001 Academi c Press.