NCIt definition : A recombinant monoclonal antibody directed against the negative immunoregulatory human
cell receptor programmed cell death protein 1 (PD-1; PD1; PDCD1; CD279), with potential
immune checkpoint inhibitory and antineoplastic activities. Upon administration, anti-PD-1
monoclonal antibody PE0105 binds to and inhibits PD-1 and its downstream signaling
pathways. This may restore immune function through the activation of T-cells and T-cell-mediated
immune responses against tumor cells. PD-1, a transmembrane protein in the immunoglobulin
superfamily (IgSF) expressed on T-cells, functions as an immune checkpoint that negatively
regulates T-cell activation and effector function when activated by its ligands programmed
cell death-1 ligand 1 (PD-L1; cluster of differentiation 274; CD274) or 2 (PD-L2);
it plays an important role in tumor evasion from host immunity.;