FIG. 2.
Effect of OMV on the induction of IL-1β production by human neutrophils. (A) Time course release of IL-1β by neutrophils stimulated with OMV. PMN were incubated with or without 5 μg of OMV per ml for up to 21 h at 37°C, and the resulting cell supernatants were processed for the determination of IL-1β levels by ELISA. The results are expressed as the mean ± the SEM for each time point of duplicated determinations from five independent experiments. The asterisks represent significant differences between OMV-treated and control PMN, i.e., “∗∗∗” indicates P < 0.005. (B) Effect of IFN-γ and IL-10 on the production of IL-1β in OMV-simulated PMN. PMN were preincubated with or without 100 U of IFN-γ or 10 ng of IL-10 per ml for 30 min and then cultured for 21 h after the addition of 5 μg of OMV per ml. The bars report the mean values ± the SEM of the percentage of enhancement or inhibition of IL-1β release by OMV-stimulated PMN, as exerted by IFNγ or IL-10, respectively, calculated from five experiments. The percent values were calculated from the difference in the amount of IL-1β produced in the absence or presence of IFN-γ or IL-10. ∗, P < 0.05; ∗∗∗, P < 0.005.