KIR2DL4 and neoplasm: Functionally, HLA-G has comprehensive immunosuppressive properties exerted in multiple steps to weaken anti-tumor immune responses by acting on immune cells through its inhibitory receptors: ILT2(CD85j/LILRB1), ILT4(CD85d/LILRB2), and KIR2DL4(CD158d) (11, 12, 55–59) (Figure 1).