Figure 4. LPS targets melanoma-resident MCs to initiate tumor immune defense.

(A–D) Tumor volume (mm³) in mice over time according to the protocol shown in Figure 2A with TC transfer. Right: Graphs depict the tumor volume at the endpoint comparing LPS- and PBS-exposed mice. Skin reconstitution with MCs was performed 6 weeks before the tumor protocol. Statistical analysis was done by 2-way ANOVA and Tukey’s multiple-comparisons test. (A) Melanoma growth in MC-deficient Kit^{W–sh/W–sh} mice with and without WT MC reconstitution (n = 8 per group). (B) Melanoma growth in MC-deficient mice because of MC-specific (Mcpt5) expression of diphtheria toxin compared with WT mice (n = 16–20 per group). (C) Tlr4^–/– mice reconstituted with WT or Tlr4^–/– MCs compared with WT mice reconstituted with WT MC (right) (n = 5–10 per group). (D) Melanoma in Mcpt5-cre⁺ IKB^fl/fl mice with MC-specific endogenous activation of NF-κB (MC NF-κB*) compared with LPS-induced exogenous NF-κB activation and PBS controls in Mcpt5-cre⁺ IKB^wt/wt or IKB^fl/wt mice (n = 8–22 per group). Means ± SEM are shown. *, #P < 0.05; ##, ‡‡P < 0.005; ***, P < 0.0005; ****, ####, ‡‡‡‡P < 0.0001.