Lymphocyte Activation Gene 3 (LAG-3)

Lymphocyte Activation Gene 3 (LAG-3), also known as CD223, is a transmembrane protein and immune checkpoint receptor with a central role in regulating T cell function and immune homeostasis. It delivers inhibitory signals that regulate immune cell homeostasis, activation and proliferation of T cells, cytokine production, and cytolytic activity of effector lymphocytes. Persistent expression of LAG-3 contributes to dysfunctional cytotoxic lymphocytes in cancer or chronic infection, making it a target for cancer immunotherapy and autoimmune disease therapies.

Other names

CD223lymphocyte activating 3

Anti-LAG-3 antibodies block the interaction of LAG-3 with its ligand MHC class II, thereby reversing LAG-3 mediated inhibition of T cell function and enhancing anti-tumor immunity. Fusion proteins act similarly by binding LAG-3 and preventing its inhibitory signaling.