FIGURE 2: Tissue-resident memory T cells (T_RM) suppress the outgrowth of persisting melanoma cells and promote a state of melanoma-immune equilibrium. This mode of tumour control is highly localised and does not rely on recirculating T cells (T_CIRC). Putative effector pathways operating during melanoma-immune equilibrium include the T_RM-derived cytokines TNFα and IFNγ, as well as the cytotoxic effector molecule perforin. While TNFα appears to play a dominant role, the contribution of the other effector molecules may be redundant.