Immunohistochemical study of inflammatory infiltrates in minor salivary glands of patients with Sjögren's syndrome and other autoimmune diseases

BACKGROUND: A study of the phenotype, activation and adhesive cells factors and cytokines in minor salivary glands in patients with primary Sjögren's syndrome (pSS), secondary Sjögren's syndrome (sSS) and autoimmune diseases (AD) without Sjögren's syndrome. PATIENTS AND METHODS: We have studied the minor salivary glands in 30 patients with pSS, 30 patients with sSS, 19 patients with AD without SS and 18 controls, using immunohistochemical techniques to analyze the molecular expression of CD3, CD4, CD8, CD20, CD25, CD14, CD56, CD11a, CDw50 (ICAM-3), HLA-DR, IL-1, TNF-α and IFN-γ in lymphocytic infiltration and epithelial cells. RESULTS: Phenotype features were similar in patients with pSS and sSS, except that CD20+ lymphocyte expression was significantly higher in the sSS group (p = 0.023). The patients affected by AD without SS had activated lymphocytes in minor salivary glands in a similar manner to patients affected by pSS and sSS. No significant differences were found in HLA-DR expression in epithelial cells. We found unusual CD25 expression in epithelial cells in patients with SS but not in patients with AD without SS. The differences between pSS and sSS are related to SS theoretical time development and to immunosuppressive treatments. CONCLUSIONS: The immunohistochemical pattern of minor salivary glands is similar in patients with pSS and sSS. Patients with AD are likely to develop immunological changes in minor salivary glands attributable to activated lymphocytes.