Recent reports indicate that DC heterogeneity may also correspond to the induction of different functions in NK cells: BDCA1+ DCs may be important for IL-12 secretion in SLO, favoring IFN-γ secretion and consequent Th1 polarization of T cells; CLEC9+BDCA3+ DCs may be relevant in peripheral tissue where, upon virus infection, they can induce NK cytolytic activity by releasing IFN-α. This evidence concerns the gene IFNA17 and viral infectious disease.