CD8A and melanoma: In the tamoxifen-induction model, developing melanomas are poorly infiltrated by CD8+ TIL (61, figures 6B and 7A, B), which may explain their observed intrinsic resistance to treatment with αPD1 (figure 1), known to require a proinflammatory TME at baseline.61 Remarkably, we observed that mice bearing αPD1-resistant melanomas when treated with skin immunization became responsive to subsequent αPD1 therapy (figure 2A).