Fig. 6: Application of DXBTZ-CB[8]/CSA in the mouse model of tumor lymphatic metastasis.

a Schematic illustration for multispectral optoacoustic imaging of lymphatic metastasis of tumor in mice after intra-footpad injection of DXBTZ-CB[8]/CSA. b Typical cross-sectional MSOT images corresponding to the popliteal fossa position of the control group and the tumor lymphatic metastasis model group. The mice were placed in the prone position for imaging. Left panel: overlay of DXBTZ-CB[8]/CSA optoacoustic signal onto the grayscale image with anatomical information. Right panel: spectrally unmixed optoacoustic signal of DXBTZ-CB[8]/CSA. Organ tags: 1: artery; 2: femur. The popliteal lymph node region of mice was delimited with a white dotted circle (ROI). c Mean MSOT intensities at ROI for the control mice and the mice with tumor lymphatic metastasis at 1 h post intra-footpad administration of DXBTZ-CB[8]/CSA (31.1 mg kg⁻¹; n = 5 animals per group). d A cryosection image of a female mouse corresponding to the cross-section location in b. e Orthogonal MIP MSOT images for the tumor lymphatic metastasis model mice. The primary tumor (PT), lymphatic vessel (LV) and sentinel lymph node (SLN) of the model mouse were pointed by white arrows in the image. f Photos for the popliteal lymph node (before and after resection) of the control mouse and the mouse (with lymphatic metastasis) 1 h post intra-footpad injection of DXBTZ-CB[8]/CSA. g Typical H&E-stained sections for the popliteal lymph node from the control mouse and the mouse (with lymphatic metastasis) 21 days post intra-footpad inoculation of 4T1 cells. The right panel displays the magnified H&E images of the areas in the black dotted box in left panel. h Immunohistochemistry images of anti-CD206-stained popliteal lymph node sections from the control mouse and the mouse 21 days post intra-footpad inoculation of 4T1 cells. i Immunofluorescence images of anti-CD44-stained popliteal lymph node sections from the control mouse and the mouse 21 days post intra-footpad inoculation of 4T1 cells. Scale bar: 50 μm. Data are presented as mean values ± SD. Statistical significance was determined by two-tailed t test. ***P < 0.001. Source data are provided as a Source Data file.