IL6 and melanoma: Further evidence that IL-6 blockade is synergistic with ICI is to be found in a melanoma model, where IL-6 blockade widens the therapeutic window of ICI; PD-1 or PD-L1 blockade, by itself, increases systemic production of IL6 as well as stimulating PD-1+ macrophages to produce IL-6 in the TME [Tsukamoto et al., 2018].