Alexa Fluor® 647 Rat Anti-Mouse CD223 Antibody (S-R624)

CD223, also known as LAG-3 (lymphocyte activation gene-3), is a type I transmembrane protein belonging to the immunoglobulin (Ig) superfamily. It is expressed on the surface of activated T cells, regulatory T cells (Tregs), natural killer (NK) cells, and some other immune cells. Structurally, it is similar to CD4 and has a higher binding affinity to MHC class II molecules than CD4. LAG-3 primarily functions as an immune checkpoint receptor, negatively regulating T-cell activation, proliferation, and cytokine production. In cancer and chronic infections, elevated LAG-3 expression is associated with T cell exhaustion, limiting anti-tumor and antiviral responses. Due to its significant role in immune regulation, LAG-3 has become a promising target for cancer immunotherapy and the treatment of autoimmune disorders.