show Abstracthide AbstractNK cell activation depends on a change in the balance between signals from inhibitory and activating receptors. The threshold values at which changes in this equilibrium drive NK activation are thought to be set by inhibitory receptor engagement during development. Here, we elucidated how the activating receptor NKG2D controls NK cell responsiveness.We evaluated the differences between wild-type mice and knockout mice harbouring Klrk1-/- (NKG2D) or Tyrobp-/- (DAP10). We aimed to understand the impact from the loss of the NK cell activating receptor NKG2D or the associated DAP10 signalling protein has on determining overall activating signalling thresholds set during NK cell development.