FIG. 6.

A delay in T-cell priming during IL-12 therapy was seen in mediastinal lymph nodes. ELIspot assays were conducted, using 150,000 cells from mediastinal lymph nodes per well and uninfected (open symbols) or M. tuberculosis-infected (closed symbols) WT DCs as stimulators. Squares, IL-12 treatment; circles, PBS treatment. (A) IFN-γ production of T cells from lymph nodes was delayed in WT mice given IL-12 compared to saline controls. (B) Similar results were seen with CD4^−/− mice. Mediastinal lymph nodes were unable to be grossly detected at days 5 and 10 postinfection. Each data point represents three or four mice and the bars represent the standard errors. Graphs represent two experiments with mediastinal lymph nodes from WT mice and one experiment with lymph nodes from CD4^−/− mice. *, P ≤ 0.05; **, P ≤ 0.01.