Figure 4. Soluble mediators of DCreg suppressor activity.

(A) - B6 DCreg with blocked PGE₂ production are less inhibitory compared to control cells (25-40% decrease in inhibition depending on the content of DCreg in culture, P<0.05, ANOVA), but still retain suppressor activity. (B) - Both B6 and I/St cell-free supernatants possessed inhibitory activity regarding T cell proliferation, but in I/St this activity is weaker (P<0.01, ANOVA). (C) - NO production: similar nitrite levels in B6 and I/St co-cultures with lung stroma from naïve mice and opposite shifts in the presence of infected stroma – slight decrease in I/St, but 2-fold increase in B6 cultures, resulting in 3-fold (P<0.01, ANOVA) differences. (D) - The content of IL-10 is significantly (P=0.04, Student’s t-test) higher in B6 compared to I/St supernatants developed on infected stroma. Mean triplicate CFU counts ± SD from 3 independent experiments are displayed.