NK cell-mediated cytotoxicity

Results from studies using purified recombinant or native cytotoxic proteins may be difficult to extrapolate directly to intact NK-cell-mediated killing because target-cell stimuli and microenvironmental components can influence which death pathways are activated.

The review argues that the specific death pathways engaged by NK cells and the tumor-cell machinery regulating them may influence both tumor elimination and the generation of antitumor T-cell responses and immune memory.

The immunological synapse formed by NK-cell receptors and adhesion molecules regulates NK-cell effector functions.

The review identifies granule exocytosis involving perforin and granzymes and death-ligand expression as the main best-characterized mechanisms of NK-cell-mediated cytotoxicity.

The review states that NK-cell-mediated cytotoxicity can activate multiple target-cell death modalities, including apoptosis, necroptosis, and pyroptosis.