Fig. 3

miR-155 and miR-146a repress meningitic E. coli PCN033-induced pro-inflammatory mediator expression. a and b U251 cells were transfected with mimic controls (miR-ctrls), miR-155 mimics (miR-155), miR-146a mimics (miR-146a), inhibitor controls (anti–miR-ctrl), miR-155 inhibitors (anti–miR-155), or miR-146a inhibitors (anti–miR-146a) for 24 h. The expression of miR-155 and miR-146a was detected by qPCR. U6 was used as an internal control. Data represented the mean + SD (n = 3/group). Statistical analysis was carried out by Student’s t test. c U251 cells were transfected as in a and b and infected with PCN033 at a MOI of 10 for 3 h. The survival bacteria were determined by plating on LB agar plates. d and e U251 cells were transfected as in a and b and infected with PCN033 at a MOI of 10 for 3 h. The expression of IL-1β, IL-6, TNF-α, MCP-1, and MIP-2 were determined by qPCR. GAPDH was used as the internal reference. Data represented the mean + SD (n = 3/group). Statistical analysis was carried out by one-way ANOVA. p < 0.05 was considered statistically significant; p < 0.01 and p < 0.001 indicated extremely significant differences