IL15 and neoplasm: Given previous findings that NK cells can lyse tumor cells without prior exposure, and that NK cell cytotoxicity can be enhanced through pre-treatment with Poly(I:C), IL-2, or IL-15 [22, 23], we therefore used ex vivo expanded NK cells to evaluate their cytotoxicity following reovirus mediated activation.The results of NK cell cytotoxicity analysis showed that stimulation with different titers of reovirus and subsequent co-culture with DLD-1 target cells at a 5:1 effector-to-target-cell (E:T) ratio enhanced NK cell cytotoxicity in a dose-dependent manner (Fig. 1a).