What is pd l1?

PD-L1 (programmed death-ligand 1) is a protein that is found on the surface of certain cells, including cancer cells and immune cells. It binds to a receptor called PD-1 (programmed cell death protein 1) on T cells, which helps regulate the immune response. When PD-L1 binds to PD-1, it inhibits the T cell response, allowing cancer cells to evade detection and attack by the immune system.

PD-L1 expression is a predictive biomarker for immunotherapy response, specifically immune checkpoint inhibitors such as anti-PD-1 and anti-PD-L1 antibodies. High levels of PD-L1 expression on tumor cells can indicate that they are more likely to respond to immunotherapy. Testing for PD-L1 expression is now a routine part of cancer diagnosis and treatment planning for several cancer types, including lung cancer, melanoma, bladder cancer, and others.