Durable transgene expression from plasmid DNAs is the key to gene therapy with non-viral vectors. A comparison of the durability of transgene expression from plasmid DNAs with the CpG-free and -containing backbones is important.,We constructed plasmid DNAs with the CpG-containing backbone, various transcription regulatory sequences with and without CpG, and the gene encoding Gaussia princeps luciferase, which is apparently non-immunogenic. The tail vein hydrodynamics-based method was used for plasmid injection into mice, and the luciferase activity in serum was tracked for 28 days.,The plasmid DNAs containing the albumin promoter [with or without the cytomegalovirus (CMV) enhancer] and the elongation factor (EF... More
Durable transgene expression from plasmid DNAs is the key to gene therapy with non-viral vectors. A comparison of the durability of transgene expression from plasmid DNAs with the CpG-free and -containing backbones is important.,We constructed plasmid DNAs with the CpG-containing backbone, various transcription regulatory sequences with and without CpG, and the gene encoding Gaussia princeps luciferase, which is apparently non-immunogenic. The tail vein hydrodynamics-based method was used for plasmid injection into mice, and the luciferase activity in serum was tracked for 28 days.,The plasmid DNAs containing the albumin promoter [with or without the cytomegalovirus (CMV) enhancer] and the elongation factor (EF)1α promoter plus the CMV enhancer exhibited long-term luciferase expression. The expression from the plasmid DNA containing the albumin promoter without the CMV enhancer was maintained for at least 24 weeks and was similar to that from the corresponding CpG-free plasmid DNA.,The results obtained in the present study suggest that special sequences/systems are unnecessary for durable transgene expression from plasmid DNAs when the proper transcription regulatory sequences are used.,© 2019 John Wiley & Sons, Ltd.