CTLA4 and neoplasm: They also block the NKG2D-dependent cytotoxicity of NK cells, and CD8 + T cells.291 Immune checkpoint pathways have been identified as crucial targets for anticancer therapies, including TIM3, TRAIL, PD1/PD-L1, CTLA4/B7, and Fas/FasL.292 TDEVs enriched with immune checkpoint ligands can inhibit tumor killing by binding to T-cell cognate receptors.