FIGURE 7.

Oral immunization of SJL mice with Salmonella-CFA/I_IC induces T_reg cells to produce elevated levels of IFN-γ and IL-13, but does not induce immune deviation. (A) CD25⁻CD4⁺ T cells and (B) CD25⁺CD4⁺ T_reg cells from SJL mice vaccinated with H647, AP331, or H696, and from naïve mice were co-stimulated in vitro with anti-CD3 and anti-CD28 mAbs, and cytokine production was measured from culture supernatants after 72 h. (A) CD25⁻CD4⁺ T cells from AP331- vaccinated mice failed to show any significant difference in cytokine production from naïve mice. H647-CD25⁻CD4⁺ T cells showed enhanced IFN-γ, and H696-CD25⁻CD4⁺ T cells showed elevated production of IL-4, IL-10, and IL-13. (B) T_reg cells elicited by AP331 vaccination produced enhanced levels of IFN-γ, IL-10, and IL-13 when compared to T_reg cells H647- or H696- vaccinated or naïve mice. In contrast, H696 induced-T_reg cells produced elevated levels of IL-4 and TGF-β. Depicted are the combined results from two separate experiments for a total of 12 samples/group ± SEM. *, P < 0.001 represents differences in cytokine production between Salmonella-vaccinated groups and naïve mice.