Immune Checkpoint (免疫检查点)

Immune checkpoints are molecules in the immune system that regulate immune responses. Immune checkpoints ensure that the immune system attacks foreign pathogens (such as bacteria, viruses, etc.) without excessively damaging normal tissues (maintaining self-tolerance, preventing autoimmune responses, etc.). Therefore, immune checkpoints will be used by some tumor cells or pathogens of infectious diseases to escape immune attack. Therefore, immune checkpoint inhibitors are increasingly used in cancer immunotherapy. Immune checkpoint inhibitors can enhance the immune system's attack on tumor cells, or block inhibitory checkpoints (such as CTLA-4, PD-1), thereby restoring effective T cell function. Overall, immune checkpoints are a biological mechanism that regulates immune responses, and are of great significance for the normal function of the immune system and the development of immunotherapy.