PDCD1 and neoplasm: Interestingly, combine treatment with GD2 specific CAR-T cell with CD3ζ, CD28, and OX40 signaling domains and pembrolizumab (anti-PD-1 mAb) may augment the anti-tumor activity of the effector T cells by improving their persistence and expansion in patients with GD2-positive tumors, such as melanoma [92].