KLRK1 and central nervous system cancer: Notably, recent preclinical work displays that CD8+ T cells achieve specific killing of glioma cells completely lacking in MHC-I expression through the NKG2D–NKG2DL interaction; however, these T cells require activation through recognition of their cognate antigen, which can be presented via myeloid cells in the surrounding TME or by neighboring MHC I+ glioma cells [191].