BCG-vaccinated C57BL/6 Il10−/− mice have sustained cytokine levels during Mtb challenge. C57BL/6 or C57BL/6 Il10−/− were vaccinated and Mtb-challenged as described in Fig. 2. Lung cells and splenocytes were isolated at 28- and 56-days post challenge and were restimulated with PPD as described in Materials and Methods. IFN-γ, TNF-α, IL-6, and IL-17A were measured in the supernatants of these restimulations by ELISA. Data shown are mean ± SEM from two combined identical independent experiments (n = 5-8 per group, per experiment) totaling 12-16 per group. ns = not significant. *p < 0.05, **p < 0.01, ***p < 0.001 by one-way ANOVA.