Immune checkpoint inhibitors

Immune checkpoints are proteins in the immune system that either turn up a signal or turn down a signal. These proteins help keep immune responses in check and can keep T cells from killing cancer cells. When these proteins are blocked, the “brakes” on the immune system are released and T cells are able to kill cancer cells better.

Examples of immune checkpoint proteins (targets) found on T cells or cancer cells include:

• IDO• TDO• PD-1• PD-L1• CTLA4• KIR• 4-1BB(also known as CD137)• OX40 (also known as CD134)• LAG3• B7‑H3(also known as CD276)• TIM3• TIGIT• BTLA• VISTA• ICOS• CD39• CD27• CD30(also known as TNFRSF8)• CD28• B7-H4(also known as B7‑S1, B7x and VCTN1)• HHLA2• Galectins