Efficient generation of recombinant adenoviral vectors by Cre-lox recombination in vitro

Background: Although recombinant adenovirus vectors are attractive for use in gene expression studies and therapeutic applications, the construction o f these vectors remains relatively time-consuming. We report here a strateg y that simplifies the production of adenoviruses using the Cre-loxP system. Materials and Methods: Full-length recombinant adenovirus DNA was generated in vitro by Cre-mediated recombination between loxP sites in a linearized shuttle plasmid containing a transgene and adenovirus genomic DNA. Results: After transfection of Cre-treated DNA into 293 cells, replication- defective viral vectors were rapidly obtained without detectable wild-type virus. Conclusion: This system facilitates the development of recombinant adenovir al vectors for basic and clinical research.