Fig 1: Characterization of CD276 expression and evaluation of humanized CD276 mAb binding and cross-species specificity. A, TCGA mRNA and protein analysis of CD276 expression in normal breast and breast cancers. **, P < 0.01; ***, P < 0.001. B, Representative image showing high CD276 expression in human TNBC tissue. Scale bar equals 70 μm. C, Representative IHC images of human normal organs stained with our humanized CD276 mAb. Scale bar equals 70 μm. D, Representative IHC images of monkey, mouse, and rat normal organs stained with humanized CD276 mAb. Scale bar equals 70 μm. E, Binding affinity (KD values) of humanized CD276 mAb for CD276 receptors from human, monkey, mouse, and rat. F, Flow cytometry analysis of humanized CD276 mAb binding to the surface of human and mouse TNBC cells and rat breast cancer cells. SSC, side scatter.