Figure 8.

Exogenous IL-2 rescues U 0126-mediated suppression of Th2 priming at low peptide concentration. (A) U 0126 (3 μM)- or DMSO-pretreated naive line 94 CD4⁺ T cells were stimulated with P13.9 cells that were preloaded with 0.01 μM pPCC. At 24 h of stimulation (indicated by arrows), 100 U/ml rhIL-2 with or without 10 μg/ml anti–IL-4 were added to the cultures. Cells were harvested at indicated time points, and relative mRNA levels for IL-4 and GATA-3 were analyzed by real-time PCR. (B) Naive line 94 CD4⁺ T cells were stimulated as described in (A). Different concentrations of rhIL-2 with or without 10 μg/ml anti–IL-4 or rat IgG1 were added to the culture at 24 h. Intracellular IL-4 and IFN-γ were stained following restimulation. The frequency of IL-4–producing cells is shown. Both experiments were repeated three times with similar results.