Clonal propagation of Epstein-Barr virus (EBV) recombinants in EBV-negative Akata cells
Journal of Virology
We lack a host cell supporting an efficient lytic replication of Epstein-Barr virus (EBV). Recently, we isolated EBV-negative cell clones from the Akata cell line (referred as Akata ؊ [N. Shimizu, A. Tanabe-Tochikura, Y. Kuroiwa, and K. Takada, J. Virol. 68:6069-6073, 1994]). Since the parental Akata line is one of the highest EBV producers, we examined whether Akata ؊ cells had become a good host for EBV propagation. The parental Akata cells have about 20 copies of EBV plasmid per cell. A drug
... id per cell. A drug resistance gene was inserted into one of them by homologous recombination. The resultant virus preparation, a mixture of wild-type and recombinant EBV, was used to infect Akata ؊ cells. After incubation in the selective medium, drug-resistant Akata ؊ cell clones were isolated and proved to be infected with recombinant EBV only. By treatment of the cells with antiimmunoglobulin antibodies, a large amount of recombinant EBV (i.e., more than 10 g/1-liter culture) was produced. In contrast, three other B-lymphoma lines, BJAB, Ramos, and Louckes, were nonpermissive for virus replication. These results indicate that Akata ؊ cells are suitable for propagation of recombinant EBV clonally, which becomes a powerful tool for determining EBV genetics and which makes it possible to use EBV as a vector for gene therapy. on May 10, 2020 by guest http://jvi.asm.org/ Downloaded from 7262 NOTES J. VIROL. on May 10, 2020 by guest http://jvi.asm.org/ Downloaded from FIG. 4. Schematic representation of the Akata cell system, which allows propagation of EBV recombinants clonally and in large quantities. neo r , Neo r gene.