DEVELOPMENT OF IMPROVED EXPRESSION VECTORS AND THEIR APPLICATIONS IN CANCER GENE THERAPY

摘要: Recombinant DNA vectors are fundamental tools in gene therapy research. A novel cloning system, pLinus, was made to facilitate vector construction by providing 32 unique restriction sites adapt fragments a single step. To compensate the low delivery efficiency of non-viral systems, we have constructed two high expression plasmid vectors, pHi1/2, incorporating transcriptional amplifier strategy into construct. In both pHi1/2 cassettes contained independent units. One unit factor, tat gene, driven strong constitutive CMV promoter. The second either an HIV1 LTR or HIV2 driving interest. Using human IL-2 cytokine as reporter and therapeutic could achieve significantly higher levels than that observed when using promoter alone. vivo injection stable pHi2-IL-2 modified Lewis Lung (LL/2) tumor clones resulted slower growth longer survival compared those mice injected with CMVdriven transfected parental cells. solve safety concern, vector, pHi-Hot, combining inducible strategies vector. first heat shock protein (hsp70B) controlling factor. Tat, which transactivates promoter, tine LTR, located downstream on same drives IL2 demonstrated that, at 42°C for 30 min, pHi-Hot while maintaining its inducibiiity. induced were achieved hsp directly. And repeated min pHi-Hot-IL-2 LL/2 clone led regression. this study, three major approaches towards facilitating improving cassette design described.