Figure 3.

Secondary cytokine response required LPS exposure. (a) Primed monocytes (NS, zymosan 100 μg/ml, live BCG 100 μg/ml, or heat-inactivated BCG 100 μg/ml) when re-stimulated with LPS produced IL-1β and TNF-α as seen before. No cytokine production was observed with Zym100 LPS re-stimulated monocytes due to the tolerant state. (b) In contrast, matched samples produced neither IL-1β nor TNF-α cytokine when re-stimulated with media only. Data are presented as mean (bar) and significance (* P < 0.05; ** P < 0.01) as compared to unstimulated (NS) controls. A Friedman test (one-way ANOVA) was followed with a Dunn’s multiple comparison test. Data are representative of two independent experiments (n = 8 per study).