(A) Purified naïve CD4 T cells from adult IL-13Rα1+/+ mice were stimulated with anti-CD3 (10μg/mL), anti-CD28 (1μg/mL), and graded amounts of rIL-12 for five days. Cells were then tested for differentiation by measuring intracellular IFNγ or IL-4 control. Zebra plots show intracellular cytokine staining on CD4+CD11c- gated cells. Cells that were not given rIL-12 were included for control purposes. (B) Naïve CD4 T cells from 1, 2, 4, and 6d old IL-13Rα1+/+ mice were cultured with or without 0.1ng/ml rIL-12 for 24h and the naïve CD4+CD62L+CD11c- cells were analyzed for IL-12Rβ2 expression. (C) Naïve CD4 T cells from 1, 2, 4, and 6d old IL-13Rα1+/+-GFP mice were stimulated with anti-CD3 and anti-CD28 antibodies in the absence or presence 0.1ng/ml rIL-12 and the differentiated CD4+CD11c-IFNγ+ Th1 cells were analyzed for IL-13Rα1 expression by GFP. Cells that were not given rIL-12 were used for control purposes. This is representative of at least 5 experments