Immune Response and Protective Efficacy of a Heterologous DNA-Protein Immunization with Leishmania Superoxide Dismutase B1

Figure 4

Antigen-specific cytokine expressing T cells three weeks after the last immunization. Integrated median fluorescent intensity (iMFI) of IFN-γ (a), TNF-α (b), IL-2 (c), and IL-10 (d). Integrated MFI was calculated as a product of the percentage of the cytokine producing CD4⁺ T cells and the median fluorescent intensity of the cytokine. Mice immunized twice with pcDNA-LdLdFeSODB1 or pcDNA-mGMCSF-LdFeSODB1 were boosted with rLdFeSODB1 protein. The control mice received three doses of pcDNA, pcDNA-mGMCSF, or CpG ODN alone. The percentage of cytokine producing CD4⁺ T cells as well as MFI was measured in stimulated spleen cells from individual mice. The mean iMFI and standard error of the mean (SEM) of five mice per group are shown. Asterisks indicate statistically significant difference between cells from antigen immunized mice and controls (). Stimulation of spleen cells with PMA/ionomycin produced consistently high response in all groups (data not shown).

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