IFN-gamma-dependent recruitment of mature CD27(high) NK cells to lymph nodes primed by dendritic cells.

NK cells have been proposed to be an initial source of IFN-gamma that supports either Th1 or CTL priming. Although NK cells reside in naive lymph nodes (LN) at a very low frequency, they can be recruited into LN draining sites of infection, inflammation, or immunization where they potentially influence adaptive immunity. In this study, we report that mature CD27(high) NK cells are predominantly recruited into the draining LN following dendritic cell (DC) challenge. Importantly, the recruitment of the CD27(high) NK cell subset in the draining LN was dependent on host IFN-gamma and the activation status of NK cells. Endogenous epidermal DC migration induced by hapten challenge also triggers NK cell recruitment to the draining LN in an IFN-gamma-dependent mechanism. Thus, our results identify that CD27(high) NK cells are the dominant population recruited to the draining LN and NK cell recruitment requires endogenous IFN-gamma in coordinating with DC migration.