Although the CTL activity and IFN-γ production in hu-PB-NK cells was not remarkably restored in NOG-IL-2/IL-15 double Tg mice, the superior increase in the number of hu-PB-NK cells in NOG-IL-2/IL-15 double Tg mice compared with NOG-IL-15 Tg mice resulted in better tumor control in vivo, indicating that using double transgenic mice could be an interesting approach. Here, IL15 is linked to neoplasm.