Figure 1.

Vitamin A impairs the conversion of iTreg cells into IL-17-producing cells during intestinal inflammation. Highly purified CD45.1⁺ Foxp3⁺ cells generated in vitro were transferred into congenic mice (CD45.2⁺) fed a vitamin A-deficient diet (VAD) or control diet. At days 1 and 3 after the adoptive transfer, the recipient mice were injected intraperitoneally with OVA + anti-CD3 to induce inflammation or OVA alone as a control. The lymphoid organs and lamina propria were dissected at day 6, and the cells were analyzed to assess the expression of Foxp3 and IL-17 production on the transferred CD4⁺ cells (CD45.1⁺). (a) Representative graph showing the percentage of Foxp3-GFP expression against IL-17 on the transferred CD4⁺ cells (CD45.1⁺). (b) Quantification of Foxp3⁺IL-17⁺ (left) and Foxp3⁺IL-17⁻ (right) cells for each condition. Means ± SEM are shown. Mann-Whitney U test ^∗ p < 0.05, ^∗∗ p < 0.01, and ^∗∗∗ p < 0.001.