Programmed cell death protein 1 (PD-1)

Programmed cell death protein 1 (PD-1) is a protein found on immune cells, specifically T cells, which help the body fight infections and cancer. When PD-1 interacts with its partners, it acts as a checkpoint that telling T cells to slow down or stop attacking, preventing excessive immune responses. Some cancer cells exploit this system by activating PD-1, effectively hiding from the immune system. PD-1 inhibitors are drugs that block this interaction, reactivating T cells and allowing the immune system to better recognize and destroy cancer cells. This approach is a key strategy in cancer immunotherapy.