The 10F.9G2 antibody is specific for mouse CD274, more commonly known as PD-L1 or B7-H1, which acts as a ligand for the T cell co-regulatory receptor PD-1 (CD279). This interaction modulates T cell antigen receptor (TCR) signaling and therefore T cell activation. PD-L1 binding to PD-1 expressed on CD4- CD8- thymocytes participates in the processes of clonal selection, elimination of autoreactive lymphocytes, and development of tolerance. PD-L1 may also bind PD-1 following the receptor’s inducible expression on activated, mature T cells, where it has been proposed to limit T cell activation. PD-L1 is one of a group of “B7” ligands whose interactions with the CD28 receptor family, also including CTLA-4 (CD152), provide a balance of co-stimulatory /co-inhibitory signaling important in T cell activation, tolerance, and autoimmunity.

The 10F.9G2 antibody may be used as a marker for PD-L1 expression on T and B cells, NK cells and on dendritic cells. It is also widely used for analysis of receptor-ligand interaction and function(s) in vitro and in vivo.