BioLegend Immune Checkpoints
In order to effectively clear out tumor cells, the immune system needs to be able to generate an appropriate inflammatory response. However, the fact that most of our immune cells contain a fail-safe mechanism to ensure they are not constantly activated is a double-edged sword. There are a number of markers found on both tumor cells and antigen presenting cells that can downregulate or suppress T cells once the corresponding ligand is bound.
Researchers are now looking into how they can prevent T cells from binding these tolerance-inducing ligands. This would keep the T cells active and ready to battle cancer. These markers have come to be known as “immune checkpoint receptors”. Although a number of immune checkpoints are being looked at, the most well-studied combinations include PD-1/PD-L1, CTLA-4/CD80 and CD86, LAG-3/MHC II, and Tim-3/Galectin 9.
Click on the receptor/ligand combination below in order to learn more about their cell distribution, function, and therapeutic role in treating cancer. You can also take a look at our thorough Cancer Immunoediting poster, which can be requested for free from our literature page.


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