Figure 2

Administration of ATRA decreased the levels of Th2- and Th17-related cytokines and down-regulated the expression of transcription factors in the lung. A. The levels of IL-4, IL-5, IFN-γ, IL-10, and IL-17 in the lung homogenates were assessed by ELISA. Compared with the control group, the levels of IL-4 and IL-5 in the lung significantly elevated in vehicle group, but ATRA significantly reduced IL-4, IL-5 levels and slightly decreased the IL-7A level, but there was no significant difference for the levels of IFN-γ or IL-10 in different groups. B. Treatment with OVA up-regulated the expression of IL-4, IL-17A mRNA in lung; ATRA suppressed these cytokine transcription levels and increased IFN-γ and T-bet mRNA expression. Meanwhile, ATRA moderately increased the IL-10 mRNA level and had no effect on Foxp3 mRNA transcription in vivo. Data represent the mean ± SEM with n = 10 for each group (***, p < 0.001; **, p < 0.01; *, p < 0.05). Data represent two independent experiments.