The invention discloses a conditionally replicating adenovirus vector for
virus replication regulated by a
TetR-KRAB-mediated transcription inhibition type Tet-On
system, adenovirus E1 region comprises the following components in the following connection sequence: 5'-CMV
promoter,
TetR-KRAB
gene,
promoter TRE3G-E1b Pro containing a
tetracycline responsive element, EcoR I
enzyme cutting site, E1B
Delta 55KD
protein-deleted adenovirus E1A-E1B19KD
gene sequence,
enzyme cutting site Spe I and mRNA transcription termination
signal SV40polyA-3'; the CMV
promoter expresses
transcription inhibitor TetR-KRAB; a
gene sequence inserted into the two
enzyme cutting sites of the EcoR I and the Spe I is a gene fragment from adenovirus E1A translation
initiation site to adenovirus E1B19KD
protein termination codon, the promoter TRE3G-E1b Pro containing the
tetracycline responsive element expresses adenovirus E1A gene, adenovirus E1B19KD gene is expressed by the own promoter of the adenovirus E1B19KD, and the packed adenovirus is named as Ad5-CMV-TetR-KRAB-TRE3G-E1bPro-
Delta 55KD. Tests show that the
virus can be loaded into mesenchymal stem cells for application in study of
tumor therapy.