CD4 + CD69 + T cells and CD4 + CD25 + FoxP3 + Treg cells imbalance in peripheral blood, spleen and peritoneal lavage from pristane-induced systemic lupus erythematosus (SLE) mice

Adaptive immune cells, including CD4 CD69 and CD4 CD25 FoxP3 regulatory T (Treg) cells, are important for maintaining immunological tolerance. In human systemic lupus erythematosus (SLE), CD4 CD25 FoxP3 Treg cells are reduced, whereas CD69 expression is increased, resulting in a homeostatic immune imbalance that may intensify autoreactive T cell activity. To analyze the mechanisms implicated in autotolerance failure, we evaluated CD4 CD69 and CD4 CD25 FoxP3 T cells and interleukin profiles in a pristane-induced SLE experimental model. For lupus induction, 26 female Balb/c mice received a single intraperitoneal 0.5 ml dose of pristane, and 16 mice received the same dose of saline. Blood and spleen samples were collected from euthanized mice 90 and 120 days after pristane or saline inoculation. Mononuclear cells from peripheral blood (PBMC), peritoneal lavage (PL) and splenocytes were obtained by erythrocyte lysis and cryopreserved for further evaluation by flow cytometry using the GuavaEasyCyte TM HT. After thawing, cells were washed and stained with monoclonal antibodies against CD3, CD4, CD8, CD25, CD28, CD69, FoxP3, CD14 and Ly6C (BD Pharmingen TM). Interleukins were quantified using Multiplex® MAP. The Mann-Whitney test and the Pearson coefficient were used for statistical analysis, and p