PREPARATION OF HIGH-TITER RETROVIRAL VECTORS USING TRANSIENT EXPRESSION SYSTEM

摘要

Retroviral vectors are widely used as a tool for introduction of a foreign gene into host genome. High viral titer preparation is required for generation of transgenic animals. In this regard, we introduced Q vector, a transient production system of retroviral vectors, to achieve high titers. In this system, an LTR promoter was replaced by CMV promoler to increase the transcriplion level of virus genomic RNA, and SV40 replication origin allows episomal replication of plasmids in cells expressing SV40large T antigen. We used this Q vector as a backbone and introduced a murine slem cell virus (MSCV) cis elements and vesicular stomatitis virus G glycoprotein (VSV-G) as an envelope. After optimization of the transfection conditions and cell cullure medium, viral tiler was increased up lo 10~6 IU (infectious unil)/ml. This liter level was comparable lo that produced by packaging cell lines.