Lymphocyte activation gene 3 in autoimmune disease: from molecular mechanisms to clinical applications.

Lymphocyte activation gene 3 (LAG3) has become an important immune checkpoint receptor, which plays a crucial role in regulating the immune response. The immunoregulatory function of LAG3 is achieved through complex receptor-ligand interactions, structure-function relationships, and unique signaling pathways. The role of LAG3 in cancers has been widely explored, and drugs targeting LAG3 are constantly emerging, demonstrating promising application prospects. In autoimmune diseases, downregulation of LAG3 leads to the breakdown of immune tolerance and excessive immune activation. In this review, we begin with the mechanisms by which LAG3 exerts its immunosuppressive function and its role in the immune system, focusing on the role of LAG3 in autoimmune diseases and recent research progress.