LAG3 / CD223 / Lymphocyte activation gene 3 Immune Checkpoint Pathway

LAG3 / CD223 / Lymphocyte activation gene 3 Immune Checkpoint Pathway: Description

The LAG3 / CD223 / Lymphocyte activation gene 3 protein bears structural similarities to CD4 and binds the same ligand, MHC class II, but with much greater affinity. LAG3 / CD223 / Lymphocyte activation gene 3 immune checkpoint pathway inhibits Ca2+ fluxes, T cell proliferation and IFNγ, TNFα and IL-2 (but not Th2 cytokine) production following TCR re-stimulation. In healthy individuals, its ex vivo expression is negligible, but it is known to be expressed on activated T and NK cells, Tregs, iNKT cells and some pDC populations. LAG3 / CD223 / Lymphocyte activation gene 3 immune checkpoint pathway plays an important but incompletely understood role in the function of these lymphocyte subsets.Recent studies have documented a role for LAG3 / CD223 / Lymphocyte activation gene 3 in CD8+ T cell exhaustion during chronic viral infection and LAG-negatively regulated the tumor-infiltrating NY-ESO-1-specific CD8+ T cells in human ovarian cancer. Demeure et al. reported that increased expression of LAG3 / CD223 / Lymphocyte activation gene 3 was found on tumor-infiltrating lymphocytes (TILs) isolated from human renal cell carcinomas and othertumors, such as melanomas and lymphomas. Importantly, LAG3 / CD223 / Lymphocyte activation gene 3 immune checkpoint pathway is closely correlated with the dysfunction of T cells in patients with chronic viral infection and cancer.