| 摘要 |
<p>A modified recombinant virus has host range genes deleted therefrom. The virus has restricted replication in the host and can express a heterologous gene product in the host even with restricted replication of the virus in the host. The modified recombinant virus is used for expressing a gene product in a host or in a cell cultured in vitro, and as a vaccine. Also described is a selection system for the cloning and expression of open reading frames in poxviruses which is based on a host range mutant. Said mutant is capable of plaquing on primary chick embryo fibroblasts and two monkey cell lines (BSC-40 or VERO) but is defective in replication in the human cell line MRC-5. Insertion of the host range gene into the deletion/recombinant restores the ability for growth on MRC-5 cells. Plasmids were constructed which allow for the rapid single-step cloning and expression of any open reading frame when recombined with the deletion/recombinant and scored for growth on MRC-5 cells.</p> |
