IL-6 and IL-8 protein release levels by L7 or L8 loop-stimulated PAMs. PAMs were stimulated with OmpP2 (10 µg/mL), loops L7 and L8 or scrambled peptide (260 nmol/mL) for 12 h. The content of IL-6 (A) and IL-8 (B) was measured by ELISA. HEPES buffer (pH 7.4) containing 0.25% (w/v) SLS was used as a mock stimulus, and the untreated cells were used as a negative control. Values are presented as the mean ± SD of three independent experiments. Data were analysed using one-way ANOVA. *p < 0.05, **p < 0.01 compared with the negative control.