Improved chitosan-mediated gene delivery based on easily dissociated chitosan polyplexes of highly defined chitosan oligomers

Köping-Höggård, Magnus; Vårum, KM; Issa, Mohamed; Danielsen, Signe; Christensen, Bjørn E.; Stokke, Bjørn Torger; Artursson, Per

doi:10.1038/sj.gt.3302312

Cited by 349 publications

(260 citation statements)

References 49 publications

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“…This is consistent with our previous studies on CS-mucin systems (Menchicchi et al, 2014). Moreover, chitosans with a Mw ~ 20 kDa have been shown to bind and protect completely the nucleic acid from enzymatic degradation (Köping-Höggård et al, 2004).…”

Section: Discussionsupporting

confidence: 92%

Chitosan as a non-viral co-transfection system in a cystic fibrosis cell line

Fernández

Santos-Carballal

Weber

et al. 2016

International Journal of Pharmaceutics

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Successful gene therapy requires the development of suitable vehicles for the selective and efficient delivery of genes to specific target cells at the expense of minimal toxicity. In this work, we investigated a non-viral gene delivery system based on chitosan (CS) to specifically address cystic fibrosis (CF). Thus, electrostatic self-assembled CS-pEGFP and CS-pEGFPsiRNA complexes were prepared from high-pure fully characterized CS (Mw ~20 kDa and degree of acetylation ~30%). The average diameter of positively-charged complexes (i.e.  ~ +25 mV) was ~200 nm. The complexes were found relatively stable over 14 h in OptiMEM. Cell viability study did not show any significant cytotoxic effect of the CS-based complexes in a human bronchial cystic fibrosis cell line (s). We evaluated the transfection efficiency of this cell line with both CS-pEGFP and co-transfected with CS-pEGFP-siRNA complexes at (N/P) charge ratio of 12. We reported an increase in the fluorescence intensity of CS-pEGFP and a reduction in the cells co-transfected with CS-pEGFP-siRNA. This study shows proof-of-principle that co-transfection with chitosan might be an effective delivery system in a human CF cell line. It also offers a potential alternative to further develop therapeutic strategies for inherited disease treatments, such as CF.

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Section: Discussionsupporting

confidence: 92%

Chitosan as a non-viral co-transfection system in a cystic fibrosis cell line

Fernández

Santos-Carballal

Weber

et al. 2016

International Journal of Pharmaceutics

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“…The longer chitosan oligomers formed soluble globules with DNA at lower charge ratios. As the chain length of chitosan increases, the binding with DNA may occur in a more cooperative manner, and soluble chitosan-DNA globules are formed at lower charge ratios [8,9]. Liu et al [10] have showed that the charge density is important by studying the formation of polyplexes at different pH values.…”

Section: Introductionmentioning

confidence: 99%

Effect of ionic strength solution on the stability of chitosan–DNA nanoparticles

Picola

Busson

Casé

et al. 2013

Journal of Experimental Nanoscience

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Chitosan-DNA nanoparticles employed in gene therapy protocols consist of a neutralised, stoichiometric core and a shell of the excess of chitosan which stabilises the particles against further coagulation. At low ionic strength, these nanoparticles possess a high stability; however, as the ionic strength increases, it weakens the electrostatic repulsion which can play a decisive part in the formation of highly aggregated particles. In this study, new results about the effect of ionic strength on the colloidal stability of chitosan-DNA nanoparticles were obtained by studying the interaction between chitosans of increasing molecular weights (5, 10, 16, 29, 57 and 150 kDa) and calf thymus DNA. The physicochemical properties of polyplexes were investigated by means of dynamic light scattering, static fluorescence spectroscopy, optic microscopy, transmission electronic microscopy and gel electrophoresis. After subsequent addition of salt to the nanoparticles solution, secondary aggregation increased the size of the polyplexes. The nanoparticles stability decreased drastically at the ionic strengths 150 and 500 mM, which caused the corresponding decrease in the thickness of the stabilising shell. The morphologies of chitosan/DNA nanoparticles at those ionic strengths were a mixture of large spherical aggregates, toroids and rods. The results indicated that to obtain stable chitosan-DNA nanoparticles, besides molecular weight and N/P ratio, it is quite important to control the ionic strength of the solution.

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“…Molecular weight (MW) is one of the main parameters affecting chitosan-mediated transfection as it influences nanoparticle size, complexation efficiency between chitosan and pDNA, rate and extent of endocytosis and eventual dissociation or 'unpacking' of the pDNA from chitosan [16,[23][24][25]. While high MW chitosan can form more stable nanoparticles, particularly when cross-linked, they may not release the pDNA efficiently thus limiting transfection.…”

Section: Introductionmentioning

confidence: 99%