title: RNA interference in vitro and in vivo using a novel chitosan/siRNA nanoparticle system.
abstract: This work introduces a novel chitosan-based siRNA nanoparticle delivery system for RNA interference in vitro and in vivo. The formation of interpolyelectrolyte complexes between siRNA duplexes (21-mers) and chitosan polymer into nanoparticles, ranging from 40 to 600 nm, was shown using atomic force microscopy and photon correlation spectroscopy. Rapid uptake (1 h) of Cy5-labeled nanoparticles into NIH 3T3 cells, followed by accumulation over a 24 h period, was visualized using fluorescence microscopy. Nanoparticle-mediated knockdown of endogenous enhanced green fluorescent protein (EGFP) was demonstrated in both H1299 human lung carcinoma cells and murine peritoneal macrophages (77.9% and 89.3% reduction in EGFP fluorescence, respectively). In addition, Western analysis showed approximately 90% reduced expression of BCR/ABL-1 leukemia fusion protein while BCR expression was unaffected in K562 (Ph(+)) cells after transfection using nanoparticles containing siRNA specific to the BCR/ABL-1 junction sequence. Effective in vivo RNA interference was achieved in bronchiole epithelial cells of transgenic EGFP mice after nasal administration of chitosan/siRNA formulations (37% and 43% reduction compared to mismatch and untreated control, respectively). These findings highlight the potential application of this novel chitosan-based system in RNA-mediated therapy of systemic and mucosal disease.
authors.affiliation: Interdisciplinary Nanoscience Center (iNANO), University of Aarhus, 8000 Aarhus C, Denmark.
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Howard
authors.forename: Ulrik L
authors.initials: UL
authors.lastname: Rahbek
authors.forename: Xiudong
authors.initials: X
authors.lastname: Liu
authors.forename: Christian K
authors.initials: CK
authors.lastname: Damgaard
authors.forename: Sys Zoffmann
authors.initials: SZ
authors.lastname: Glud
authors.forename: Morten Ø
authors.initials: MØ
authors.lastname: Andersen
authors.forename: Mads B
authors.initials: MB
authors.lastname: Hovgaard
authors.forename: Alexander
authors.initials: A
authors.lastname: Schmitz
authors.forename: Jens R
authors.initials: JR
authors.lastname: Nyengaard
authors.forename: Flemming
authors.initials: F
authors.lastname: Besenbacher
authors.forename: Jørgen
authors.initials: J
authors.lastname: Kjems
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D048271:Chitosan / Q000737:chemistry*; D017930:Genes, Reporter / Q000235:genetics; D006801:Humans; D008168:Lung / Q000378:metabolism; D051379:Mice; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000737:chemistry* / Q000235:genetics*; D013057:Spectrum Analysis
chemical_list: D034741:RNA, Small Interfering; D048271:Chitosan