Vascular endothelium and lymphocyte adhesion molecules in minor salivary glands of patients with Sjogren's syndrome.

The aim of this study was to examine the distribution and types of adhesion molecules expressed over endothelial cells and the ligands present on lymphocytes which infiltrate exocrine glands in patients with Sjogren's syndrome. Minor salivary gland biopsies were examined from twelve patients with Sjogren's syndrome and eight normal subjects for the presence of adhesion molecules using monoclonal antibodies and an Indirect Immunoperoxidase technique. There was an increased expression of intercellular adhesion molecule-1 (ICAM-1, CD54) on endothelial cells, lymphocytes, fibroblasts and salivary gland epithelial cells. In addition we documented the expression of endothelial leukocyte adhesion molecule-1 (ELAM-1) on endothelial cells in salivary glands from patients but not the controls. Many of the endothelial cells expressing these adhesion molecules in patients with Sjogren's syndrome had the morphological appearance of high endothelial venules. V-CAM-1 was shown to be present in some of the salivary biopsies from patients with Sjogren's syndrome. Lymphocytes infiltrating salivary glands strongly express LFA-1 (CD11a/CD18) molecules. Some infiltrating lymphocytes, and most monocytes, expressed C3bi-R (CD11b/CD18) and the p150.95 (CD11c/CD18) antigens on their cell surface. The results of this study reveal the enhanced expression of vascular endothelial and lymphocyte adhesion molecules on the minor salivary glands of patients with Sjogren's syndrome. The presence of such receptors and their putative ligands indicate an important role for these molecules in the pathogenesis of Sjogren's syndrome.