Furthermore, accumulated evidence suggests that IL2 signaling in the TME favors responsiveness to PD1 blockade.70–73 As shown in figure 7H, I, skin immunization resulted in the recruitment of increased levels of IL2+CD4+ TIL in the tumor core, which may at least partially explain the ability of skin immunization to convert PD1-resistant tumors into αPD1-responsive tumors (figures 2A and 4D). Here, CD4 is linked to neoplasm.