DiR (Bridgen, Beijing, People’s Republic of China) was incubated with hCTL membrane-derived vesicles for 30 min to monitor the biodistribution of the nanoparticles in vivo. A subcutaneous xenograft model of gastric cancer was established by injecting 106 MKN-45 cells in 100 μL of PBS subcutaneously in male Balb/c nude mice. Treatment started when the tumor volume reached ~300 mm3. Three tumor-bearing Balb/c nude mice received LDI (2 Gy), and three did not. They were all injected intravenously with TPNPs the day after LDI. Then, the mice were anesthetized and scanned at different time intervals using a Maestro™ Automated In Vivo Imaging System. For resected organ imaging, the animals were euthanized, and the tumors and organs were excised and imaged.
DiO-loaded TPNPs were injected into the tail vein of tumor-bearing mice. After 24 h, the mice were sacrificed under deep anesthesia. Tumors were harvested and processed for immunostaining. Frozen sections were stained using rabbit anti-human CD31 (Abcam, Cambridge, UK) followed by secondary antibodies with Cy3-conjugated Goat Anti-rabbit IgG (H+L; Abcam). Tumor cells were stained using DAPI. Images were taken using a confocal microscope.
DiO-loaded TPNPs were injected into the tail vein of tumor-bearing mice. After 24 h, the mice were sacrificed under deep anesthesia. Tumors were harvested and processed for immunostaining. Frozen sections were stained using rabbit anti-human CD31 (Abcam, Cambridge, UK) followed by secondary antibodies with Cy3-conjugated Goat Anti-rabbit IgG (H+L; Abcam). Tumor cells were stained using DAPI. Images were taken using a confocal microscope.