469. Optimization of the Lentivirus Vector Containing the MSCV-U3 and EF1|[alpha]| Double Internal Promoters

The double gene vector carrying the expression units of the therapeutic gene and the reporter gene is widely used, since the reporter proteins such as the GFP and the DsRed are useful for measuring the titer of vector stock and the tracing gene modified cells. However, the activities of the double promoters in a single vector are often inhibited by the so called 'promoter interference'. The internal ribosomal entry site (IRES) is being utilized to overcome this problem, but the expression of the second gene is not sufficient for the sensitive detection. In this study, we attempted to optimize the double gene lentivirus vector to achieve a high expression level of both genes.