Programmed cell death protein 1 receptor (PD-1) (PD-1)

Programmed cell death protein 1 (PD-1) is a type I transmembrane protein and a member of the immunoglobulin superfamily that functions as a critical inhibitory immune checkpoint receptor (UniProt Q15116). Primarily expressed on the surface of activated T cells, B cells, and macrophages, PD-1 plays a vital role in maintaining peripheral tolerance and preventing autoimmunity by dampening T-cell activity during inflammatory responses (NCBI Gene 5133). In many cancers, the PD-1 pathway is co-opted by tumor cells that express ligands PD-L1 and PD-L2, leading to T-cell exhaustion and immune evasion (StatPearls: NBK459363). Pembrolizumab is a high-affinity, humanized monoclonal antibody that binds to PD-1, preventing its interaction with these ligands and thereby restoring the ability of cytotoxic T cells to recognize and eliminate malignant cells (DrugBank DB09037). This therapeutic approach has demonstrated significant efficacy across a broad range of solid and hematologic malignancies, although it is frequently associated with immune-related adverse events due to the systemic loss of immune inhibition (StatPearls: NBK459363).

Other names

PDCD1CD279SLEB2hPD-1hPD-l

PD-1 inhibition; monoclonal antibody binding to the PD-1 receptor to block interaction with ligands PD-L1 and PD-L2, thereby reversing T-cell exhaustion and enhancing anti-tumor immune responses (StatPearls: NBK459363).