BM degradation and ECM remodeling enhance DC migration. (A) Heatmap of genes involved in BM and ECM remodeling. (B and C) Levels of laminin expression and of fibrillar collagen (SHG signal) were analyzed around collectors in CTR and INF ear skin. Representative whole-mount images of PROX1⁺ lymphatic collectors and corresponding quantifications are shown in B for laminin (scale bar, 50 µm) and C for fibrillar collagen (scale bar, 10 µm). (D and E) Laminin and fibrillar collagen were quantified in ear skin explants at 0 (CTR) and after 4 h of incubation. (F and G) Ear skin explants were incubated with TNFα and IFNγ in the presence or absence of PRN. 24 h later, fibrillar collagen levels were quantified (F) around lymphatic collectors and (G) in the tissue. (B–G) Pooled data from three whole-mounts per condition in three independent experiments. (H–J) Ear skin explants were incubated for 4 h with or without PRN before adding 1:1 mixtures of fluorescent WT and Itgb1^−/−-deficient DCs for 4 h. (H) Representative images showing WT and Itgb1^-/KO DCs in capillaries and collectors at the end of the experiment. (I and J) Quantification of the impact of PRN treatment on the ratio of DCs inside the vessel, in comparison to all DCs in per image. Results for WT DCs (I) and Itgb1^−/− DCs (J). Left: Capillaries (cap). Right: Collectors (col). Each dot represents the average from one experiment (n = 4 experiments with one or two explants/condition/experiment). Ratios from the same experiment are connected by a line. Scale bars, 50 µm (B, C, and H). (B–F) Unpaired Student’s t test. (H and I) Paired Student’s t test. *, P < 0.05; **, P < 0.01; ***, P < 0.001; and ****, P < 0.0001.