Immune checkpoint
Brakes on the immune system that stop T cells attacking healthy tissue. Tumours pull these brakes to protect themselves; checkpoint inhibitor drugs release them so T cells can attack the cancer.
PD-1 on a T cell, when it meets PD-L1 on another cell, tells the T cell to stand down; CTLA-4 acts earlier, when T cells are first activated. Tumours coat themselves in PD-L1 and exploit this, and antibodies that block PD-1 (pembrolizumab, nivolumab), PD-L1 (atezolizumab, durvalumab) or CTLA-4 (ipilimumab) restore the attack, producing durable remissions in melanoma, lung, kidney, bladder and many other cancers since 2011. The price is autoimmune side effects when the brakes come off everywhere, and only a minority of patients respond, which drives the search for newer checkpoints (LAG-3, TIGIT) and combinations. The 'checkpoint' in 'cell-cycle checkpoint' is an unrelated concept.
Pages like this
not linked directly; found by shared links- PathwayT-cell exhaustion
Shares TIGIT, Hallmark: avoiding immune destruction, LAG-3, CTLA-4.
- TermImmuno-oncology (IO) and checkpoint blockade
Shares Durvalumab, Atezolizumab, Immune-related adverse events (irAEs), Hot vs cold tumours.
- Key paperASCO 2021 guideline: how to recognise and manage the immune-related side effects of checkpoint inhibitors
Shares CTLA-4, Atezolizumab, Immune-related adverse events (irAEs), Ipilimumab.
- Key paperIwai and Honjo: tumours use PD-L1 to escape T cells, and blocking it restores attack
Shares Atezolizumab, PD-1 / PD-L1 immune checkpoint & T-cell activation, PD-L1, Nivolumab.
- TargetTIM-3
Shares TIGIT, LAG-3, PD-1 / PD-L1 immune checkpoint & T-cell activation, PD-1.
- IdeaExtended-interval immunotherapy: give checkpoint inhibitors every 8-12 weeks once stable
Shares Atezolizumab, PD-L1, Nivolumab, PD-1.
- TrialKEYNOTE-006
Shares CTLA-4, Ipilimumab, PD-1, Pembrolizumab.
- PathwayThe cancer-immunity cycle
Shares CTLA-4, Hot vs cold tumours, Ipilimumab, PD-1 / PD-L1 immune checkpoint & T-cell activation.