Figure 6. CD103 expression on CD8 T cells promotes skin access and T_RM cell formation.

(A–B) Vitiligo (induced as in Fig. 1A) was tracked in (A) wild-type (WT) mice vs. CD103^−/− mice or (B) CD8^−/− mice reconstituted with WT or CD103^−/− naïve CD8 T cells. Data are representative of 2 independent experiments, each with n ≥ 7 mice/group (C–D) Relative proportions of vitiligo-affected mice (from A and B, respectively) with localized vs. disseminated vitiligo; with dissemination defined by depigmentation extending beyond a 2 cm² area surrounding the surgical site. (E–J) Mice received 10⁴ naïve, congenically distinct WT and CD103^−/− pmel cells, admixed at a 1:1 ratio, 1d prior to treatment as in Fig. 1A. Flow cytometry was performed to detect relative frequencies of WT vs. CD103^−/− pmel cells (gated on CD8⁺ cells) in (E) skin of vitiligo-affected mice 45d post-surgery, (F) skin on the day of surgery, (G) lymph nodes 4d prior to surgery, (H) lymph nodes of vitiligo-affected mice 45d post-surgery, and (I) tumors on the day of surgery. (J) Analysis of lymph nodes from panel G, to detect IFN-γ production by CD8⁺Thy1.1⁺ pmel cells, following 5h ex vivo restimulation with cognate (gp100_25–33) or irrelevant (OVA) peptide. Symbols represent individual mice. (E–I) Significance was determined by Wilcoxon matched pairs test, pairing CD103^−/− and WT pmel populations in the same mouse (denoted by line-connected points). Arrows indicate mean percent difference between WT and CD103^−/− pmel population sizes. Data are pooled from 2 independent experiments, each with n ≥ 3 mice/group, with the exception of G, which is representative of 3 experiments each with n ≥ mice/group. (J) Significance was determined by Kruskal-Wallis test; data are representative of 2 independent experiments each with n = 4 mice/group. NS denotes p > 0.05.