| 摘要 |
<p>A system for generating recombinant, human parainfluenza virus, particularly infectious, recombinant, human parainfluenza virus type 3 (HPIV-3) is provided. In one embodiment, the system comprises a clone comprising a nucleotide sequence that encodes a full-length, positive sense, anti-genome of HPIV, and at least one support clone comprising a nucleotide sequence that encodes the HPIV P protein and the HPIV L protein. In another embodiment, the system further comprises a support clone which comprises a nucleotide sequence that encodes the HPIV NP protein. The present invention also provides a clone which comprises a nucleotide sequence encoding the full-length, positive sense, anti-genome of HPIV-3. The clone also comprises an RNA polymerase promoter operatively linked to the HPIV-3 antigenome-encoding sequence. In a preferred embodiement, the clone further comprises a nucleotide sequence which encodes a ribozyme immediately downstream from the sequence encoding the HPIV3 anti-genome. The present invention also relates to a method of preparing recombinant HPIV-3 virus having site-specific mutations in the HPIV-3 genome. The method comprises preparing a clone comprising a modified HPIV-3 antigenomeencoding sequence; introducing the modified HPIV-3 clone and support clones which comprise nucleotide sequences encoding an HPIV-3 P protein, an HPIV-3 L protein, and, preferably, an HPIV-3 NP protein into host cells; and culturing the host cells under conditions that allow for synthesis of the modified HPIV3 antigenome and the L, P, and NP proteins of HPIV-3.</p> |
