FIG 5.

IL-10 prevents Salmonella clearance during the acute phase of persistent infection but not during the chronic phase. (A and B) Mice infected with WT Salmonella for 14 days (acute) were intraperitoneally (i.p.) administered anti-IL-10 neutralizing antibody continuously every 3 days for 21 days (total of 35 days), at which time organs were harvested and plated for bacterial burdens. (A) Spleens and (B) livers of cytokine-blocked mice or controls are shown. In a separate experiment, mice were injected with an anti-IL-10R blocking antibody 1 day prior to infection with WT Salmonella and bacterial burdens were assessed 8 days (acute) postinfection in (C) spleen and (D) liver. (E) Mice were first infected with WT Salmonella for 40 days (chronic) at which time anti-IL-10 neutralizing antibody was administered i.p. every 3 days for 21 days (total of 61 days), at which time organs were harvested and plated for bacterial burdens. An unpaired Student’s t test was used to determine statistical significance between groups (A to D) or a two-way ANOVA and Sidak’s multiple-comparison test were used (E). *, P < 0.05; **, P < 0.01; ***, P < 0.001. Representative of 2 or 3 independent repeats for each experiment.