Schematic representation of activation thresholds and kinetics of resting CD56^dim NK-cell responses. (A) Approximate times required for induction of different NK-cell responses such as degranulation (surface expression of CD107a), chemokine secretion (MIP-1α and MIP-1β), and cytokine secretion (IFN-γ and TNF-α) are indicated on the time scale. (B) The figure depicts the relative signal strength required for induction of different NK-cell responses such as degranulation (surface expression of CD107a), chemokine secretion (MIP-1α and MIP-1β), and cytokine secretion (IFN-γ and TNF-α).