programmed cell death protein 1

biology

Also known as: PD-1

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Last updated

July 21, 2026

Quick Summary

Programmed cell death protein 1 (PD-1) is a protein found on the surface of T cells, which are a type of immune cell. PD-1 acts as a crucial regulator of immune responses. In essence, it functions as a "brake" on the immune system, preventing T cells from attacking the body's own healthy cells and causing autoimmune diseases.1

However, cancer cells can exploit this mechanism. They can express molecules that bind to PD-1, effectively shutting down the T cells' ability to recognize and eliminate the cancer. This is why PD-1 is a target for cancer immunotherapy. By developing antibodies that block PD-1, scientists have created treatments that release the "brake" on T cells, allowing them to attack and destroy cancer cells more effectively. This approach has shown significant promise in treating various types of cancer.234

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Tasuku Honjo
…colleagues discovered a protein called programmed cell death protein 1 (PD-1) on the surface of T cells. In later experiments, Honjo and colleagues deduced the function of PD-1 as a negative regulator of immune responses and found that PD-1 deficiency played a critical role in the development of lupus-like autoimmune…
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…colleagues discovered a protein called programmed cell death protein 1 (PD-1) on the surface of T cells. In later experiments, Honjo and colleagues deduced the function of PD-1 as a negative regulator of immune responses and found that PD-1 deficiency played a critical role in the development of lupus-like autoimmune…
Read More