A human embryonic kidney cell line 293 is widely used for adenovirus production and propagation. With this cell line, however, replication-competent virus (RCV) is frequently generated, especially during large-scale production and successive propagation because 293 cells contain not only E1 gene but also non-E1 adenovirus gene. Homologous recombination between non-E1 region of 293 genomic DNA and its homologous region in the recombinant adenoviral vector generate RCV. To overcome this problem, we developed a new packaging cell line, Hela-E1, which contains minimum E1 region and from which non-E1 adenoviral region that is homologous with recombinant adenovirus vector was excluded. No RCV was detected during adenovirus propagation in Hela-E1 compared to in 293. In addition, adenovirus-p53 produced in HeLa-E1 was able to overexpress p53 protein when introduced into an ovarian cancer cell line, SKOV3. These results may have a significant impact on the development of packaging cell lines for replication-deficient adenovirus production.
Adenoviridae/*genetics/physiology ; Adenovirus E1 Proteins/*genetics/metabolism ; Cell Line ; Genes, Viral ; Genes, p53 ; *Genetic Vectors ; *Hela Cells ; Human ; Protein p53/genetics/metabolism ; Recombination, Genetic ; Support, Non-U.S. Gov't ; Tumor Cells, Cultured ; Virus Cultivation ; Virus Replication