Fig. 1 Schematic diagram of immune checkpoint interaction
Immune checkpoint therapies have attracted amounts of attention from scientists who are devoted to cancer treatment. What is immune checkpoint? It is a kind of co-stimulatory and inhibitory signal for regulating the antigen recognition of T cell receptor (TCR) in the process of immune responce. When immune system is attacking pathogens, these immune checkpoint molecules can protect the normal tissues from damage. The cancer cells cleverly escape from immune attack by dysregulating immune checkpoint related proteins. Immune checkpoint therapy relys on functioning immune system with agonists of co-stimulatory signals or antagonists of inhibitory signals. Over these years there are two immune checkpoint receptors that have been actively studied: cytotoxic T‑lymphocyte-associated antigen 4 (CTLA-4 / CD152) and programmed cell death protein 1 (PD1 / PDCD1 / CD279). The corresponding antibodies can inhibit the functioning of the receptors and enhance antitumour immunity. Furthermore, multiple additional immune checkpoints, representing promising targets for anti-cancer therapy are under active development, more therapies based on immune checkpoint for more cancers are on the way to the market.
Immune checkpoint related reference
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