| 摘要 |
This invention relates to a mammalian host cell, preferably HEK 293, containing a mammalian artificial chromosome ( also known as a MAC, satellite artificial chromosome, SATAC, an artificial chromosome expression system or an ACES) which is stably replicated and segregated alongside endogenous chromosomes in a mammalian host cell for creating more efficient retroviral packing cell lines. The artificial chromosome comprises nucleic acid sequences encoding a replication defective retroviral vector particle, preferably derived from HIV-1, HIV-2, SIV, FIV, EIAV or Visna. The retroviral vector particle comprises the RNA genome of the retroviral vector particle and genes encoding the gag (group specific antigen or HXB2 790-2292), pol (DNA polymerase) and env (viral envelope, GP160, GP120, GP41 or envelope glycoprotein) proteins. The endogenous chromosomes of the host cell also contains a nucleic acid sequence as described above. Further embodiments of the invention provide mammalian cells comprising such artificial chromosomes and methods for their use in producing retroviral particles. |
