Enhanced numbers of IFN-γ+ and TNF-α+ expressing NK and NK T-cells were seen in VIPhyb-treated WT and VIP-KO mice, with peak numbers of IFN-γ+ NK cells and TNF-α+ NK cells seen 40 hours after mCMV infection, compared with PBS-treated WT mice (Fig. 7B). The gene discussed is VIP; the disease is infection.