title: DNA uptake, intracellular trafficking and gene transfection after ultrasound exposure.
abstract: Ultrasound has been studied as a promising tool for intracellular gene delivery. In this work, we studied gene transfection of a human prostate cancer cell line exposed to megahertz pulsed ultrasound in the presence of contrast agent and assessed the efficiency of fluorescently labelled DNA delivery into cell nuclei, which is necessary for gene transfection. At the sonication conditions studied, ~30% of cells showed DNA uptake 30min after sonication, but that fraction decreased over time to ~10% of cells after 24h. Most cells containing DNA had DNA in their nuclei, but the amount varied significantly. Transfection efficiency peaked at ~10% at 8h post sonication. Among those cells containing DNA, ~30% of DNA was localized in the cell nuclei, ~30% was in autophagosomes/autophagolysosomes and the remainder was "free" in the cytoplasm 30min after sonication. At later times up to 24h, ~30% of DNA continued to be found in the nuclei and most or all of the rest of the DNA was in autophagosomes/autophagolysosomes. These results demonstrate that ultrasound can deliver DNA into cell nuclei shortly after sonication and that the rest of the DNA can be cleared by autophagosomes/autophagolysosomes.
authors.affiliation: School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0100, USA.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.affiliation: School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0100, USA.
authors.forename: Jing
authors.initials: J
authors.lastname: Yan
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, Georgia Institute of Technology, Atlanta, GA 30332, USA.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Santangelo
authors.affiliation: School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0100, USA; Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, Georgia Institute of Technology, Atlanta, GA 30332, USA. Electronic address: prausnitz@gatech.edu.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Prausnitz
mesh_terms: D001692:Biological Transport; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000235:genetics; D004247:DNA / Q000235:genetics*; D005434:Flow Cytometry; D018014:Gene Transfer Techniques; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D015612:Phonophoresis; D013010:Sonication; D014162:Transfection / Q000379:methods*
chemical_list: D004247:DNA
keywords: Acoustic cavitation; DNA uptake; Gene transfection; Intracellular trafficking; Sonoporation; Ultrasound sonication