Fig. 2.

Interleukin-4 (IL4) promotes invariant natural killer T (iNKT) cell-dendritic cell (DC) crosstalk and T-helper type 1 (Th1) responses. a–c Phosphorylated signal transducer and activator of transcription 6 (STAT6) in CD11c⁺ DCs (a) and IL12p70 (b) and IFNγ levels (c) in supernatant. iNKT cells were activated for 8 h by DCs pulsed with αGC (1 μg/ml) with or without immunoglobulin G (IgG) 2b (isotype control), an anti-IL4 antibody, an anti-IL4R antibody, and an anti-IL12 antibody. Data are presented as the mean ± SEM of more than nine biological replicates. d–f Phosphorylated STAT6 in carboxyfluorescein succinimidyl ester-positive (CFSE⁺) BMDCs in the spleen (d) and levels of IL12p70 (e), IFNγ, and IL4 in the serum (f) of WT recipient mice 8 h after intravenously (i.v.) injecting α-galactosylceramide (αGC)-pulsed WT or Il4ra^−/− CFSE⁺ BMDCs. Data are presented as the mean ± SEM of five mice per group. Statistical analysis was performed using one-way analysis of variance (ANOVA) with the Tukey’s post test. *P < 0.05; **P < 0.01; and ***P < 0.001