Figure 5.

Butyrate treatment negatively impact Th9 cells in the lungs of OVA-challenged mice. Male C57BL/6 mice were intraperitoneally (IP) injected with OVA (30 μg) + Al(OH)3 (1.6 mg) at days 0 and 7. Mice also received 250 μl of either PBS or butyrate (1M) (IP) at days 0, 1, 2, 7, 8, and 9. OVA-sensitized mice were nebulized with an OVA solution (3%) for 15 min at days 14, 15, and 16. The group that received butyrate during sensitization was also treated during challenge. A control group was sensitized and challenged without OVA. Euthanasia was performed 24 h after the last challenge (A). Lungs were digested, cells stimulated with PMA (50 ng/ml), ionomycin (500 ng/ml) and brefeldin A (5 μg/ml) for 4 h at 37°C and 5% CO₂, and stained with monoclonal antibodies to determine the frequencies of IL-9+, IL-13+, and FOXP3+ CD4+ T cells by flow cytometry (B). Bar graphs show the frequencies of IL-9+ (C), IL-13+ (D) and FOXP3+ (E) CD4+ T cells in the different groups. Data are shown as mean ± SD. One-way ANOVA followed by Tukey's multiple comparison test were used for statistical analysis. n = 5–7 mice per group. NS, not significant.