Fig. 2.

The introduction of the inlB deletion on the ΔactA mutant does not abrogate the ability of strains to induce potent antigen-specific T cell responses. C57BL/6 mice were vaccinated i.v. with 1 × 10⁷ colony-forming units (CFU) of the indicated strain. OVA-specific CD8⁺ T cell immunity was assessed on day 7 after vaccination by using intracellular cytokine staining. (A) Representative dot blots of SL8-stimulated spleen cells are shown. (Left) ΔactA/ΔinlB. (Center) ΔactA-OVA. (Right) ΔactA/ΔinlB-OVA. PerCP, peridinin chlorophyll protein. (B) The average percentage of OVA-specific CD8⁺ T cells of eight mice is shown.