CD274 and cancer: There is also a peptide mimetic with nanomolar potencies resembling the sequence involved in the PD-1/PD-L1 interaction according to the time-resolved fluorescence resonance energy transfer (TR-FRET) assay, the mouse splenocyte proliferation rescue assay in the presence of recombinant PD-L1 or co-cultured with PD-L1-expressing cancer cells, or IFN-γ production in a cytomegalovirus (CMV) or human immunodeficiency virus (HIV) protein-stimulated cytotoxic T lymphocyte [2,7].