Programmed Death Protein 1 (PD-1)

Programmed death protein 1 (PD-1), also known as CD279, is a cell surface receptor that functions as an immune checkpoint. It is primarily expressed on activated T cells, B cells, NK cells, activated monocytes, and dendritic cells. PD-1 interacts with its ligands, PD-L1 and PD-L2, to down-regulate immune responses and promote self-tolerance by suppressing T cell inflammatory activity. This pathway is often exploited by tumors to evade immune surveillance, making it a target for cancer immunotherapy. Dysregulation of the PD-1 pathway is also implicated in autoimmunity, infection, transplantation, and allergy.

Other names

CD279

Blocking PD-1 or its ligands (PD-L1, PD-L2) with monoclonal antibodies restores effective anti-tumor responses by preventing the inhibition of T cell activity.