Identifies a transmembrane protein involved in cellular and humoral immune response regulation expressed in a variety of cancers on tumor and/or immune cells. Binding of PD-L1 to its ligand PD-1, which is expressed by various immune cell types including T cells, transmits an inhibitory signal that attenuates T cell function, expansion, and survival. Many tumor types can express PD-L1, including breast, ovarian, gastric, pancreatic, lung and renal cell carcinomas, and classical Hodgkin lymphoma. PDL1 expression by tumor cells is thought to inhibit the local immune response to the tumor, at least in part by binding to T cell PD-1 and protecting the tumor from T cell mediated immunity; therefore, blockade of the PD1/PDL1 axis by humanized monoclonal antibodies has emerged as a promising new cancer therapy.
A formalin-fixed, paraffin-embedded (FFPE) tissue block is preferred specimen typeorOne (1) unbaked, unstained slide for H&E staining (required) and two to three (2-3) positively charged unstained slides (all cut at 4-5 microns) for each test/antibody orderedBlock and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.For PD-L1 LDT evaluation, tissue submitted must have ≥100 viable tumor cells present.
Use cold pack for transport. Make sure cold pack is not in direct contact with specimen.