Immune checkpoint, illustration - Stock-Fotografie

Illustration of immune checkpoints, regulators of the immune system. The interaction between PD-L1 (programmed cell death 1 ligand 1, red molecule) on the surface of a cancer cell (red) and the immune checkpoint PD-1 (programmed cell death protein 1, blue molecule) on a T-cell (blue) inhibits T-cell killing of tumour cells