P8-04 Immunological profile of plasmacytoid dendritic cells and mast cells in Sjogren's syndrome

Abstract

Although the role of lymphocytes in the pathology of Sjogren's Syndrome (SS) has been investigated, the role plasmacytoid dendritic cells (PDCs) and mast cells (MCs) remains poorly understood.Lip biopsy specimen from 178 SS and 7 Sicca syndrome (Sicca) were analyzed for histological scores and density of PDCs and MCs. Lymphocytes infiltration, acinar atrophy and intralobular fibrosis were observed with increased pDCs and MCs in SS compared to Sicca patients. Positive correlation was observed in pDCs density with lymphocytes infiltration and MCs density with intralobular fibrosis in primary SS but not in secondary SS. Within the primary SS, CXCL13+ cells density positively correlated with lymphocyte infiltration and pDCs density. Double staining with anti-CXCL13 and anti-CD68 revealed that majority of CXCL13+ cells are macrophages, and that pDCs and CXCL13+ cells are localized at the surrounding area of the duct. Our data suggests the role of PDCs in lymphocyte infiltration and MCs in intralobular fibrosis in primary SS. Moreover, CXCL13 expression suggests the involvement of multiple lineage cells in the early stage of the disease, and MCs in the mid to late stage.