title: Ultrasound and microbubble-targeted delivery of small interfering RNA into primary endothelial cells is more effective than delivery of plasmid DNA.
abstract: Ultrasound and microbubble-targeted delivery (UMTD) is a promising non-viral technique for genetic-based therapy. We found that UMTD of small interfering RNA (siRNA) is more effective than delivery of plasmid DNA (pDNA). UMTD (1 MHz, 0.22 MPa) of fluorescently labeled siRNA resulted in 97.9 ± 1.5% transfected cells, with siRNA localized homogenously in the cytoplasm directly after ultrasound exposure. UMTD of fluorescently labeled pDNA resulted in only 43.0 ± 4.2% transfected cells, with localization mainly in vesicular structures, co-localizing with endocytosis markers clathrin and caveolin. Delivery of siRNA against GAPDH (glyceraldehyde-3-phosphate dehydrogenase) effectively decreased protein levels to 24.3 ± 7.9% of non-treated controls (p < 0.01). In contrast, 24 h after delivery of pDNA encoding GAPDH, no increase in protein levels was detected. Transfection efficiency, verified with red fluorescently labeled pDNA encoding enhanced green fluorescent protein, revealed that of the transfected cells, only 2.0 ± 0.7% expressed the transgene. In conclusion, the difference in localization between siRNA and pDNA after UMTD is an important determinant of the effectiveness of these genetic-based technologies.
authors.affiliation: Departments of Physiology and Cardiology, VU University Medical Center, Amsterdam, The Netherlands; Department of Clinical Pharmacology, Groningen Institute for Drug Exploration (GUIDE), University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. Electronic address: ljm.juffermans@vumc.nl.
authors.forename: Lynda J M
authors.initials: LJ
authors.lastname: Juffermans
authors.affiliation: Department of Clinical Pharmacology, Groningen Institute for Drug Exploration (GUIDE), University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; Interuniversity Cardiology Institute of the Netherlands, Utrecht, The Netherlands.
authors.forename: Bernadet D M
authors.initials: BD
authors.lastname: Meijering
authors.affiliation: Department of Clinical Pharmacology, Groningen Institute for Drug Exploration (GUIDE), University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; Interuniversity Cardiology Institute of the Netherlands, Utrecht, The Netherlands.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Henning
authors.affiliation: Department of Clinical Pharmacology, Groningen Institute for Drug Exploration (GUIDE), University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Leo E
authors.initials: LE
authors.lastname: Deelman
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D018274:Electroporation / Q000379:methods; D042783:Endothelial Cells / Q000166:cytology / Q000502:physiology* / Q000528:radiation effects*; D019220:High-Energy Shock Waves; D045423:Microbubbles; D010743:Phospholipids / Q000528:radiation effects*; D010957:Plasmids / Q000008:administration & dosage / Q000235:genetics*; D034741:RNA, Small Interfering / Q000008:administration & dosage / Q000235:genetics*; D013010:Sonication / Q000379:methods*; D013459:Sulfur Hexafluoride / Q000528:radiation effects*; D013552:Swine; D014162:Transfection / Q000379:methods*
chemical_list: D010743:Phospholipids; D034741:RNA, Small Interfering; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride
keywords: Endocytosis; Endothelial cells; Plasmid DNA; Pore formation; Small interfering RNA; Transfection; Ultrasound and microbubbles