Expression of cell adhesion molecules in the salivary and lacrimal glands of Sjogren's syndrome

Abstract

We attempted to determine whether cell adhesion molecules, including vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and E-selectin (endothelial-leukocyte adhesion molecule-1; ELAM-1), are involved in the lymphoid cell infiltration of the salivary and lacrimal glands in Sjogren's syndrome (SS) patients. Both immunohistochemical analysis and the reverse-transcripts polymerase chain reaction (RT-PCR) were used to analyze the expression of VCAM-1, ICAM-1, ELAM-1, very late antigen 4 (VLA-4 [alpha 4,beta 1]), lymphocyte function-associated antigen-1 (LFA-1), interferon-gamma (IFN-gamma), tumor necrosis factor (TNF), and interleukin-1 beta (IL-1 beta). Immunohistochemical analysis of salivary gland biopsies from SS patients showed a marked expression of VCAM-1 and ICAM-1 in the venules surrounded by infiltrated CD4+ CD45RO+ T cells. E-selectin was expressed on vascular endothelium with weak intensity. Increased levels of VCAM-1, ICAM-1, IFN-gamma, and IL-1 beta mRNA were demonstrated by RT-PCR, whereas E-selectin mRNA were weakly expressed in SS lacrimal and salivary gland tissues. This is in contrast with strong expression of ELAM-1 in IL-1 beta-stimulated human umbilical vascular endothelial cells (HUVEC) in vitro. Cytokine-mediated up-regulation of VCAM-1 and ICAM-1 that facilitates the recruitment of VLA-4 and LFA-1 expressing T cells might contribute to lymphoid cell infiltration in the salivary and lacrimal glands in SS.