title: Electroporation in combination with a plasmid vector containing SV40 enhancer elements results in increased and persistent gene expression in mouse muscle.
abstract: Gene transfer into muscle upon injection of plasmid DNA is feasible but occurs with low frequency. However, by using electroporation after injection of plasmid DNA into mouse muscle it has been demonstrated that gene expression can be increased more than 150-fold. In this communication, we have used this technique in combination with plasmids containing a tandem repeat of three 72-bp DNA elements from the SV40 enhancer to study gene expression. Our results show that the combination of electroporation and a plasmid vector carrying these DNA elements results in increased and more persistent gene expression of the luciferase reporter gene in BALB/c mouse muscle. At 14 days after gene delivery, the gene expression was 16-fold higher in muscles injected and electroporated with the plasmid carrying the SV40 enhancers than with control plasmid. We have also studied the effects of the vehicle in which the plasmid was delivered, and the DNase inhibitor aurintricarboxylic acid (ATA), on gene expression. By combining ATA with 150 mM sodium phosphate buffer we were able to obtain a 2-fold increase in gene expression compared to delivery of the plasmid in physiological saline. These results are of importance for the development of efficient delivery techniques for naked DNA.
authors.affiliation: Gene Therapy Center, The Clinical Research Center, Karolinska Institutet, Huddinge University Hospital AB, SE-141 86 Stockholm, Sweden. Pontus.Blomberg@vecura.com
authors.forename: Pontus
authors.initials: P
authors.lastname: Blomberg
authors.forename: Malihe
authors.initials: M
authors.lastname: Eskandarpour
authors.forename: Song
authors.initials: S
authors.lastname: Xia
authors.forename: Christer
authors.initials: C
authors.lastname: Sylvén
authors.forename: Khalid B
authors.initials: KB
authors.lastname: Islam
mesh_terms: D000818:Animals; D001312:Aurintricarboxylic Acid / Q000494:pharmacology; D001483:Base Sequence; D002460:Cell Line; D017931:DNA Primers; D003851:Deoxyribonucleases / Q000037:antagonists & inhibitors; D018274:Electroporation; D004742:Enhancer Elements, Genetic; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000235:genetics*; D005822:Genetic Vectors; D051379:Mice; D008807:Mice, Inbred BALB C; D010710:Phosphates / Q000737:chemistry; D010957:Plasmids; D013539:Simian virus 40 / Q000235:genetics*
chemical_list: D017931:DNA Primers; D004791:Enzyme Inhibitors; D010710:Phosphates; D001312:Aurintricarboxylic Acid; D003851:Deoxyribonucleases; C018279:sodium phosphate