Authors: Shankaralingappa A*
PD-1, or programmed cell death protein 1, is indeed a critical immune checkpoint receptor expressed on activated T lymphocytes, including tumor-specific CD4+ helper and CD8+ killer T cells. Originally, PD-1 was identified as a regulator of cell death, but its role in immune regulation has since been recognized as crucial in the context of cancer immunotherapy. When PD-1 binds to its ligands, primarily PD-L1 and PD-L2, which are often overexpressed on tumor cells and other immune cells within the tumor microenvironment, it down regulates T cell activity and contributes to immune evasion by tumors. This interaction suppresses the cytotoxic function of T cells, allowing tumors to evade immune surveillance and continue to grow unchecked [1].
Keywords: PD-1; Cancer; Cancer Immunotherapy; Cells
