Fig. 2
Receptor activation by EcO83-OMVs. HEK-293 cells expressing (A) hTLR2, hTLR4 and hTLR5, B hNOD1 and hNOD2 were treated with the respective positive control (Pam3CSK 1 µg/ml, LPS 1 µg/ml, recFLA-ST 100 ng/ml, Tri-DAP 5 µg/ml, MDP 5 µg/ml), fixed E. coli O83 (107 CFU/ml), EcO83-OMVs (OMVs; 1 ng/ml, 10 ng/ml, and 100 ng/ml for TLR4; and 10 ng/ml, 100 ng/ml and 1000 ng/ml for TLR2, TLR5, NOD1 and NOD2) or medium only. Receptor activation was detected as an increase in IL-8 production. Data were analysed using a One-Way ANOVA followed by post-hoc Tukey’s multiple comparison test. *p < 0.5; **p < 0.05; ***p < 0.01; ****p < 0.001; + = significant difference between positive and negative control. Data are representative of three independent experiments. Mean ± SD is shown. Significant differences between EcO83-OMVs and the negative controls are indicated n.d. = not detected