The role of IL-15 in priming NK cells has not been extensively studied in mouse models of malaria, but work by Ing et al. indicates that DC-derived IL-15 enhances NK cell production of IFN-γ in combination with IL-12 (67, 74); this is consistent with in vitro studies of human NK cells showing that IL-15 is an important priming signal for NK cell activation (38), and that combinations of cytokines are required to drive IFN-γ production by NK cells (8, 31, 32, 75). This evidence concerns the gene IFNG and malaria.