Figure 4

Cytokine levels in infected mice serum and culture supernatants of stimulated THP-1 cells.
(A) Cytokine production in the BALB/c mice infected with the designated strains at 4, 8, 12 and 16 h after infection. **P < 0.01 for the comparison between the wild-type strain 05ZYH33 and ΔsspA-1 mutant; ##P < 0.01 for the comparison between the wild-type strain 05ZYH33 and ΔvirD4–89K mutant. (B) Cytokine production by stimulated THP-1 cells. ***P < 0.001 indicates a significant difference in comparison with the non-stimulated cells (Blank)c. All these data were obtained from three independent experiments.