FIG 4.

Intracellular cytokine staining of IFN-γ production by CD4⁺ and CD8⁺ T cells from C57BL/6 mice. Splenocytes were obtained from mice that were naive or chronically infected with T. gondii and stimulated with ESA as an antigen-specific positive control (1 µg/ml), ConA as a nonspecific positive control (1 µg/ml), Sumo as a negative control (1 µg/ml), MIC1, MIC4, or MIC6 (1 µg/ml), or MIC3 (0.5 µg/ml) for 24 h. The experiment included 5 naive and 10 chronically infected mice. Ordinary one-way ANOVA with Sidak’s multiple-comparison test was used to compare results between naive and infected cells.