Figure 4. Ht31 blocks the ability of PKA activators to stimulate antigen presentation and T cell activation.

Day 5 DC were incubated in the absence (black bar) or presence of 10 µM forskolin (green bars) or 1 µM PGE₂ (purple bars) and in the absence or presence of 100 µM Ht31 (red and red hatched bars) or 100 µM Ht31p (blue and blue hatched bars). CFP10 protein antigen (0.03 µg/ml) was added and after 1 hr incubation at 37°C, 5% CO₂, antigen specific CD4⁺ clonal T cells were added. IFN-γ production was assayed by ELISPOT after 16 hr at 37°C, 5% CO₂. Six experiments were normalized and averaged. Error bars are S.E.M. Student TTEST reveals significance P<0.05(*).