FIG. 4.

Effects of FljB on B7-1 and B7-2 expression on murine bone marrow-derived dendritic cells. For panels A and B, wt dendritic cells were incubated with various concentrations (10 to 10,000 ng/ml) of FljB in the presence or absence of polymyxin B (1 μg/ml) for 24 h. For panels C and D, wt or TLR4 ko dendritic cells were incubated with various concentrations (10 to 10,000 ng/ml) of FljB for 24 h. Expression profiles represent the mean fluorescence intensity (MFI) of B7-1 and B7-2 expression on CD11c⁺ cells (A and C) and the percentage of CD11c⁺ cells expressing B7-1 and B7-2 (B and D). Data are the means of six separate experiments. *, **, and *** indicate significance differences between nonstimulated and FljB-stimulated DC at P < 0.05, P < 0.01, and P < 0.001, respectively.