Figure 2. Colonization profile of EcN in the murine B16 tumor model and characterization of Tum-5 expression in vivo.

1×10⁵ B16F10 cancer cells were inoculated into the right axillary subcutaneous of C57BL/6 mice. After 7–10 days, the mice were injected with 5×10⁶ CFU/100 μl EcN (Lux). (A) The distribution of the bacteria in the tumor-bearing mice were detected using IVIS. (B) The tumor, liver, kidney, and spleen of the mice were isolated at different times and observed using IVIS. (C) Tum-5 was confirmed to be successfully expressed in the tumor tissue by IHC (200×) using its specific antibody. Almost no positive signal was observed in tumor sections in the PBS-, EcN-, EcN (28a)-treated mice. “Dpi” means “days post infection.”