Tasmanian Devils are threatened by a fatal Cancer and Science has just discovered the reason why
2 Programmed death, what does it mean
Checkpoint molecules named PD-1 or programmed death-1 and PD-L1 or programmed death ligand -1 are now the most critical regulatory agents of immunotherapy against cancer. But though they are used for keeping the onslaught of the immune system in check, they are also used by cancer as a molecular shield against any attack by the immune system. This is one common factor found in the disease. PDl-1 is the main agent that works as a regulatory barrier against the cancer killer PD-1 or T-cells.Tasmanian devil facial tumor that uses this kind of molecular deception to spread.
The PD-1 molecule is common to several immune cells but is more specific to anti cancer responses that are initiated by T-cells or Lymphocytes. Each time a cancer killing T-cell interacts with PD-L1 which acts as the regulator, the action of the T-cell is stopped. The T-cell then undergoes what is known as programmed death or it could just remain idle bereft of any role. In the worst case scenario, The T-cell may also prevent other immune cells to do their job of targeting the cancer. This is what is happening in the devil facial tumor resulting in the subsequent deaths of Tasmanian Devils.