biostudies-literatureUnknown7(1)Caldwell CBlocking the interaction between Programmed Death Ligand 1 (PD-L1) and its receptor, PD-1, is an effective method of treating many types of cancers. Certain tumors overexpress PD-L1, causing host immune cells that express PD-1 to bind PD-L1 and cease killing the tumor. Inhibition of PD-L1 and PD-1 binding can restore host immunity towards tumor killing, and many new drugs have been developed to target this interaction. Current methods of PD-L1 diagnosis have shown to vary based on the antibody, detection kit brand, antigen retrieval method, and clinically defined methods by the FDA. To refine detection of PD-L1, we have identified a peptide, RK-10, and used it to detect PD-L1 expressing tumors with immunohistochemistry or flow cytometry. Flow cytometry was performed on cell lines and patieScientific reports13682https://www.ebi.ac.uk/biostudies/studies/S-EPMC5651871biostudies-literatureIdentification and Validation of a PD-L1 Binding Peptide for Determination of PDL1 Expression in Tumors.PMC5651871Caldwell CHammer RDKannan RJohnson CEBalaji GABalaji VNfalseIdentification and Validation of a PD-L1 Binding Peptide for Determination of PDL1 Expression in Tumors.Blocking the interaction between Programmed Death Ligand 1 (PD-L1) and its receptor, PD-1, is an effective method of treating many types of cancers. Certain tumors overexpress PD-L1, causing host immune cells that express PD-1 to bind PD-L1 and cease killing the tumor. Inhibition of PD-L1 and PD-1 binding can restore host immunity towards tumor killing, and many new drugs have been developed to target this interaction. Current methods of PD-L1 diagnosis have shown to vary based on the antibody, detection kit brand, antigen retrieval method, and clinically defined methods by the FDA. To refine detection of PD-L1, we have identified a peptide, RK-10, and used it to detect PD-L1 expressing tumors with immunohistochemistry or flow cytometry. Flow cytometry was performed on cell lines and patie2017-01-01T00:00:00Z2017 Oct2026-04-30T06:56:23.615Z2019-03-27T02:59:37ZS-EPMC56518712905791910.1038/s41598-017-10946-2