Notch signal is required for the initiation of IL-5-producing Th2 cells mediated by MCPIP1. (A) The mRNA levels of Notch ligands in naïve WT and zc3h12a2−/− CD4 T cells stimulated with anti-CD3/CD28 Abs were measured by qRT-PCR (n=3). (B) Naïve zc3h12a−/− CD4 T cells were treated with GSI and anti-CD3/CD28 Abs for 3 days, and then stained for Gata3, IL-4 and IL-5 (n=3). (C) A summary of three independent experiments as in (B) was shown. (D) Total zc3h12a−/− CD4 T cells were treated with GSI and anti-CD3/CD28 Abs for 3 days and then stained for Gata3, IL-4 and IL-5. (E) Total CD4 T cells of WT (CD45.2−) and zc3h12a−/− (CD45.2+) mice were cultured in the same well at 1:1 ratio with anti-CD3/CD28 Abs and GSI for 3 d, rested for 3 d, and then stimulated by P/I for 4 h. Cytokine-producing cells were measured by FACS gated on either CD45.2+ (zc3h12a−/−) or CD45.2− cells (WT). *: p< 0.05, **: p<0.01, ***: p< 0.001.