Background
PD-L1, also called human programed cell death ligand 1, is a transmembrane protein that play a major role in suppressing the immune system during particular events such as pregnancy, tissue allografts, autoimmune disease, virus infection and cancer. PD-L1 binds to its receptor PD-1 on activated T cells, B cells, and myeloid cells, to modulate activation or inhibition. Upregulation of PD-L1 can allow cancer cell to evade the host immune system.
293T-OS8 stable cell was used as an artificial antigen presenting cells (APCs), OS8 could function as a membrane anchored T cell engager that directly activates TCRinT cell-based assay.
