Fig. 8
Longitudinal imaging of PPIs in a tumor and monitoring of tumor metastases in a mouse liver. Approximately 1 × 106 MTLn3 cells expressing DrSplit were injected into the mouse liver. The mice (n = 4) were imaged at multiple time points after tumor cell injection, and rapamycin was injected via the tail vein ~40–44 h before each PA imaging. a–d PA images of the mouse on a day 5, b day 15, c day 24, and d day 33 after injection of tumor cells, where the white arrows indicate the secondary tumor. LIR images are overlaid on the anatomical images. The overlay image shows the DrSplit signal in color and the background blood signal in gray. Scale bar, 5 mm. e Tumor growth curve, in-plane tumor area vs. time (quantified from LIR images). Error bars represent s.e.m. for results from four animals. f A representative H&E histological image of a harvested left lobe of a tumorous liver, showing the tumor metastasis, where the primary tumor and secondary tumor are bordered by green and yellow lines, respectively. Scale bar, 1 mm. The close-up H&E image shows the secondary tumor, which can be clearly differentiated from normal tissue. Scale bar, 100 µm
