Construction of recombinant adenoviral vector carrying human tissue inhibitor of metalloproteinase-1 gene and its expression in vitro

BACKGROUND: Overexpression of human tissue inhibitors of metalloproteinase-1 (TIMP-1) may play an antitumor role in inhibiting hepatocellular carcinoma (HCC) growth and progression. The aim of the study was to construct a recombinant adenovirus vector carrying hTIMP-1 cDNA for liver gene therapy and observe its expression in vitro.

METHODS: The full-length cDNA of hTIMP-1 was positively cloned into the adenoviral shuttle vector pAdTrack-CMV, and then cotransformed into competent BJ5183 cells with the adenoviral backbone plasmid pAdEasy-1. Thus, a recombinant adenovirus AdhTIMP-1 containing full-length cDNA of hTIMP-1 was generated by homologous recombination in E. coli. AdhTIMP-1 was then packaged and amplified in adenoviral packaging cells, or human embryonic kidney 293 cells. The viral titer was checked by green fluorescent protein (GFP), and the expression of hTIMP-1 in vitro was detected by the techniques of Western blot and RT-PCR.

RESULTS: The recombinant adenovirus vector carrying hTIMP-1 was constructed and confirmed by restriction endonuclease analysis and DNA sequence analysis. The transcription of TIMP-1 mRNA in 293 cells was checked by RT-PCR and TIMP-1 protein could be detected in the culture by Western blot analysis.

CONCLUSION: The successful construction of recombinant adenoviral vector carrying human TIMP-1 and the effective expression in vitro has laid a foundation for further study of its antitumor function and may pave the way for future application in liver gene therapy.