Murine models of Sjögren's syndrome.

Autoimmune MRL/lpr, MRL/+, and NZB/W mice all develop lacrimal gland inflammatory lesions, which consist of focal mononuclear inflammatory cell infiltrates. Each strain has a different immunocytochemical profile, which appears to be related to the underlying immunologic defects present in that mouse. The appearance of these lesions parallels the evolution of the systemic autoimmune disease. The lesions are dynamic over time with the early appearance of CD4+ T cells (helper T cells) for each strain. Subsequently, there is an accumulation of B cells over time in MRL/+ and NZB/W mice. In the two more rapidly evolving mouse models, MRL/lpr and NZB/W, there is a progressive decline in the percentage of CD8+ cells. Conversely, in the slowly evolving MRL/+ lacrimal gland lesions, there is a persistent and unchanging percentage of CD8+ T cells (suppressor/cytotoxic T cells). Autoimmune mice provide models for the human disorder Sjögren's syndrome and a mechanism for better understanding the immunopathogenesis of autoimmune lacrimal gland disease.