Figure 4. Lack of dietary aryl hydrocarbon receptor (AhR) ligands impairs Langerhans cells migration, thereby increasing Th2 responses.
(A, B) Mice were placed on AhR-poor or indole-3-carbinol (I3C) diet for 3 wk of adaptation prior to the start of experiments. (A) Density of epidermal Langerhans cells was assessed by imaging Cd207(Langerin)-eGFP+ cells. Representative images are shown (n = 5 per condition). Median is shown. (B–D) Papain or vehicle (PBS) was injected in the footpad at day 0. (B) After 24 hr (vehicle and papain) or 48 hr (papain), dendritic cells numbers were assessed in the draining lymph nodes. Median is shown (n = 11–14 in three independent experiments). (C, D) Mice were fed with the I3C diet for 3 wk of adaptation prior to the start of experiments. (C) Mice were treated with vehicle or AhR inhibitor CH-223191 at day 0. After 48 hr, dendritic cells numbers were assessed in the draining lymph nodes. Median is shown (n = 9 in three independent experiments). (D) Cd207(Langerin)-DTR mice or WT littermates were injected with Diphtheria Toxin 3 d prior to papain treatment. At day 6 after papain treatment, cells from the draining lymph nodes were analyzed. Normalized numbers of lymph nodes T cells were restimulated ex vivo, and cytokine secretion was measured in the supernatant after 24 hr. Median is shown (n = 11–17 in three independent experiments). One-way ANOVA. For all panels *p<0.05; **p<0.01; ***p<0.001.
Figure 4—figure supplement 1. Analysis of cutaneous allergy.
