INFILTRATING MONONUCLEAR-CELLS IN SALIVARY-GLANDS AND KIDNEYS IN AUTOIMMUNE MRL/MP-LPR/LPR MICE EXPRESS IL-2 RECEPTOR AND PRODUCE INTERFERON-GAMMA

The salivary gland inflammatory lesions and renal vasculitic lesions of autoimmune MRL/lpr mice were analyzed for the presence of activated lymphocytes. Immunohistologic analysis revealed that the majority of lymphocyte‐like cells in salivary glands and kidneys expressed CD4 antigen (>50%). Lesser numbers of interleukin‐2 receptor (IL‐2R) expressing and interferon‐gamma (IFN‐γ)‐producing cells were present (1–5%). CD4+, IL‐2R+, and IFN‐γ+ mononuclear cells were found in small inflammatory foci. In larger inflammatory foci the IFN‐γ‐producing cells were detected in the periphery in comparable numbers as the IL‐2R expressing cells although with different location. Large numbers of cells in the inflammatory foci also expressed MHC Class II molecules (>50%). The expression of IL‐2R and production of IFN‐γ in the tissue lesions indicate presence of activated inflammatory T cells. Production of IFN‐γ by the infiltrating mononuclear cells may induce Class II antigens on epithelial cells and stimulate further T cell migration into the inflammatory site. Copyright © 1990, Wiley Blackwell. All rights reserved