Figure 10. Induction of Treg cells by vitamin D reduces the inflammatory response to oxazolone and decreases the numbers of Th17 cells in the skin of Pglyrp3 ^−/− mice.

(A) Vitamin D applied to the skin of Pglyrp3 ^−/− mice together with oxazolone reduces ear swelling compared to Pglyrp3 ^−/− mice similarly treated with oxazolone alone. (B–D) Vitamin D applied to the skin of Pglyrp3 ^−/− mice together with oxazolone increases the percentages of Treg cells in the ears and cervical lymph nodes and reduces the percentages of Th17 cells in the ears compared to the application of oxazolone alone, measured on day 20 by flow cytometry. Means ± SEM of 8 mice/group (A–C; *, P<0.05; **, P<0.005; oxazolone versus oxazolone + vitamin D) or representative dot plots (D) are shown.