Figure 5
From: Tumor-targeted delivery of biologically active TRAIL protein
Validation and toxicity. (a) Comparison of the numbers of sTRAIL-expressing E. coli DH5α in both tumor and normal tissues at 4 days post-injection of viable bacteria into tumor-bearing mice through the tail vein. The experiments were repeated at least three times. Bacterial clones from the tumor plate were determined by PCR assay using the corresponding sTRAIL primers. ‘—’ indicates negative control with E. coli DH5α (empty vector) as PCR template. (b) Immunohistochemical staining for sTRAIL protein on different organs obtained from day 4 post-injection of sTRAIL-expressing E. coli DH5α. Scale bars, 50 μm. (c) Hepatotoxicity in tumor-bearing nude mice after systemic administration of E. coli DH5α-expressed sTRAIL. Serum samples were collected 4 and 30 days after tail-vein injection and aminotransferase/aspartate aminotransferase was measured using standard method. The values represent the mean±s.d. for 10 animals. (d) H&E-stained liver sections from the same animals as in panel c on day 30 after tail vein-injection. Scale bars, 50 μm. H&E, hematoxylin–eosin; sTRAIL, soluble TRAIL; TRAIL, tumor necrosis factor (TNF)-related apoptosis-inducing ligand.
