Fig. 2

SHH002-hu1 specifically targets Fzd7⁺ cells and Fzd7⁺ TNBC tumor tissue. a. Characterization of SHH002-hu1 by immunofluorescent staining of transfected cells. SHH002-hu1 showed strong binding signal (red) to Fzd7 overexpressing HEK293T cells, HEK293T cells not transfected or transfected with empty vector (GFP label) were used as control. Bar = 50 μm. b. Western blot assay to detect the expression of Fzd7 in TNBC cells. The detection antibody was Rabbit Anti-Human Fzd7 purchased from Abcam. c. IF assay to detect the binding of SHH002-hu1 with Fzd7 high-expressing MDA-MB-231/MDA-MB-468 cells. Bar = 50 μm. d. The bio-distribution of NIRB-SHH002-hu1 was evaluated by the NIRB imaging assay in MDA-MB-231-bearing nude mice. In blocking experiments, free SHH002-hu1 inhibited the probes from binding to the tumor sites. e. Tumor/normal tissue ratios calculated at 8 h post-injection of probe groups into MDA-MB-231-bearing nude mice from the region of interest. Data were given as the mean ± SD (n = 5), ^**p < 0.01