Environmental and hormonal factors, in concert with an appropriate genetic background, are believed to trigger Sjögrens syndrome, which dysregulates epithelial cells and allows aberrant homing and activation of dendritic cells (DCs), T cells, and B cells. Dendritic cells are antigen-presenting cells  that process antigen material and present it to other T cells. Following the migration of lymphocytes into the glands in response to chemokines and specific adhesion molecules, T cells interact with epithelial cells. Epithelial cells are further activated by proinflammatory cytokines (IL-1β, IFN-γ, and TNF), which are produced by adjacent T cells. The early accumulation of plasmacytoid dendritic cells in the target tissues, which produce high levels of type 1 IFNs, seems important, as these cells can further dysregulate the immune response through abnormal retention of lymphocytes in the tissues and their subsequent activation. IFN-α stimulates the production of B-cell activating factor (BAFF) by epithelial cells, DCs, and T cells. BAFF stimulates aberrant B-cell maturation, leading to the emergence of self-reactive B cells, which locally produce autoantibodies, in a germinal centre-like structure (GC-like), which is also the location of lymphomagenesis (origin of lymphoma). Programmed cell death
Dysregulation of apoptosis (programmed cell death) is believed to play a role in the pathogenesis of a variety of autoimmune diseases, though its role in Sjögrens syndrome is controversial. Both the Fas and Fas ligand proteins are overexpressed in primary Sjögrens patients, while expression of BCL-1, which is known to downregulate apoptosis, was found significantly reduced in acinar and ductal epithelial cells of Sjögrens patients compared to healthy people.
[Journal Article] Journal of Craniofacial Surgery. 14(1):37–40, 2003. Mandel L. Surattanont F. Bilateral parotid swelling: a review. [Review] [160 refs] [Journal Article. Review] Oral Surgery Oral Medicine Oral Pathology Oral Radiology & Endodontics. 93(3):221–37, 2002. External links

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