Programmed death-ligand 1 is a 40kDa type 1 transmembrane protein that has been speculated to play a major role in suppressing the immune system during particular events such as pregnancy, tissue allografts, autoimmune disease and other disease states such as hepatitis. Normally the immune system reacts to foreign antigens that are associated with exogenous or endogenous danger signals, which triggers a proliferation of antigen-specific CD8+ T cells and/or CD4+ helper cells. The binding of PD-L1 to PD-1 or B7.1 transmits an inhibitory signal that reduces the proliferation of antigen-specific T-cells in lymph nodes, while simultaneously reducing apoptosis in regulatory T cells (anti-inflammatory, suppressive T cells) - further mediated by a lower regulation of the gene Bcl-2.

The antibody is stable for at least 1 year from the date of receipt when stored at -20°C to -70°C. Reconstituted antibody can also be aliquotted and stored at 4°C for 1 month or at -20°C to -70°C in a manual defrost freezer for many months without detectable loss activity. Please avoid freeze-thaw cycles.