FIGURE 7.

NKp30 oligomerization drives NK cell cytotoxicity. Upon IL-2 stimulation a variety of activating NK cell receptors including NKp30 are up-regulated on the plasma membrane of NK cells. Based on our data, we hypothesize that increased plasma membrane NKp30 leads to formation of NKp30 oligomers, which contact cellular ligands in the plasma membrane of target cells. This interaction is mediated by two binding sites within the NKp30 ectodomain resulting in increased ligand binding affinity or even de novo formation of composite binding sites. Finally, these presumably cooperative receptor-ligand interactions promote robust NKp30-dependent NK cell cytotoxicity.