title: Characterization of transient expression system for retroviral vector production.
abstract: The production of retroviral vectors using a transient expression system has been improved to obtain a high-titer virus preparation that is difficult to produce using packaging cell lines due to the cytotoxic or cytostatic effect of transgenes. Here, we used one such production method, the so-called Q-vector system, and examined its potential for virus production. The Q-vector system could produce a similar level of viral vectors compared with the packaging cell system but the production seemed to depend on the size and nature of transgenes. In the process of investigation of the quantitative difference in viral components between the transient expression system and the packaging cell system, we found that the Q-vector system could express higher amounts of viral RNA and proteins compared with the packaging cell system. However, this did not lead to a higher virus titer compared with that produced by the packaging cell system. This suggests that retroviral RNA transcribed from the plasmid in the transient system seemed to be used mainly for translation and only some of the RNA molecules were packaged in viral particles.
authors.affiliation: Department of Biotechnology, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
authors.forename: Akitsu
authors.initials: A
authors.lastname: Hotta
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Saito
authors.forename: Kenji
authors.initials: K
authors.lastname: Kyogoku
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Kawabe
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Nishijima
authors.forename: Masamichi
authors.initials: M
authors.lastname: Kamihira
authors.forename: Shinji
authors.initials: S
authors.lastname: Iijima
mesh_terms: D000818:Animals; D002460:Cell Line; D005821:Genetic Techniques; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors; D006801:Humans; D051379:Mice; D041681:NIH 3T3 Cells; D010957:Plasmids / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D012367:RNA, Viral / Q000737:chemistry* / Q000235:genetics; D012190:Retroviridae / Q000235:genetics*; D014162:Transfection; D019076:Transgenes
chemical_list: D012333:RNA, Messenger; D012367:RNA, Viral