Figure 2: Spleen CD4+CD25+FOXP3+ T cells are rSSP4-specific. Mice were i.p. immunized with 10 μg/mouse of rSSP4 or administered PBS. After three immunizations, spleen cells were stimulated in vitro with ConA, rSSP4, or nonstimulated for 72 h, and surface expression of CD25 and intracellular expression of FOXP3 were measured in spleen cells from both nonimmunized and immunized mice. Shown cells are CD4+ lymphocytes. Results are representative of four independent experiments.