Relationship between the physical shape and the efficiency of oligomeric chitosan as a gene delivery system in vitro and in vivo
(2003) In Journal of Gene Medicine 5(2). p.130-141- Abstract
- Background Chitosans of high molecular weights have emerged as efficient. nonviral gene delivery systems, but the properties and efficiency of well-defined low molecular weight chitosans ((.) 5 kDa) have not been studied. We therefore characterized DNA complexes Of Such low molecular weight chitosans and related their physical shape and stability to their efficiency as gene delivery systems in vitro and in vivo.Methods Individual complexes between six different chitosan oligomers (6-, 8-, 10-, 12-, 14- and 24-mers) and fluorescence-labeled T4 DNA were visualized and classified into six physical shapes using video-enhanced fluorescence microscopy. The effects of chitosan chain length, charge ratio (+/-) and solvent properties (pH and ionic... (More)
- Background Chitosans of high molecular weights have emerged as efficient. nonviral gene delivery systems, but the properties and efficiency of well-defined low molecular weight chitosans ((.) 5 kDa) have not been studied. We therefore characterized DNA complexes Of Such low molecular weight chitosans and related their physical shape and stability to their efficiency as gene delivery systems in vitro and in vivo.Methods Individual complexes between six different chitosan oligomers (6-, 8-, 10-, 12-, 14- and 24-mers) and fluorescence-labeled T4 DNA were visualized and classified into six physical shapes using video-enhanced fluorescence microscopy. The effects of chitosan chain length, charge ratio (+/-) and solvent properties (pH and ionic strength) on the stability and structure of the complexes were studied. Gene expression in vitro and in vivo were studied using a luciferas
reporter gene.Results Free DNA appeared as extended coils. Chitosan complexes had, a variety of physical shapes depending on the experimental conditions. in general, the fraction of complexes that had nonaggregated, globular structures increased with increasing chain length of the chitosan oligomer, increasing charge ratio and reduction of pH (from 6.5 to 3.5). A further increase in charge ratio for globular complexes or a further reduction in pH (to 2.5) increased the fraction of aggregates, indicating a window where pharmaceutically desirable globules are obtained. Gene transfection efficiencies in vitro and in vivo were related to the physical shape and stability of the complexes. Only the 24-mer formed stable complexes that gave a high level of gene expression comparable to that of high molecular weight ultrapure chitosan (UPC) in vitro and in vivo.Conclusions Chitosan oligomers form complexes with DNA in a structure-dependent manner. We conclude that the 24-mer, which has more desirable physical prope
ties than UPC, is more attractive as a gene delivery system than the conventional high molecular weight chitosans. Copyright (C) 2002 John Wiley Sons, Ltd. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/122078
- author
- Köping-Hoggard, M ; Mel'nikova, Y S ; Vårum, K M ; Lindman, Björn LU and Artursson, P
- organization
- publishing date
- 2003
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Gene Medicine
- volume
- 5
- issue
- 2
- pages
- 130 - 141
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- wos:000181051000004
- scopus:0242322948
- pmid:12539151
- ISSN
- 1521-2254
- DOI
- 10.1002/jgm.327
- language
- English
- LU publication?
- yes
- id
- 70ca9436-e66e-46b5-963e-11f3ddbf85dc (old id 122078)
- date added to LUP
- 2016-04-01 12:11:20
- date last changed
- 2022-03-28 21:29:27
@article{70ca9436-e66e-46b5-963e-11f3ddbf85dc, abstract = {{Background Chitosans of high molecular weights have emerged as efficient. nonviral gene delivery systems, but the properties and efficiency of well-defined low molecular weight chitosans ((.) 5 kDa) have not been studied. We therefore characterized DNA complexes Of Such low molecular weight chitosans and related their physical shape and stability to their efficiency as gene delivery systems in vitro and in vivo.Methods Individual complexes between six different chitosan oligomers (6-, 8-, 10-, 12-, 14- and 24-mers) and fluorescence-labeled T4 DNA were visualized and classified into six physical shapes using video-enhanced fluorescence microscopy. The effects of chitosan chain length, charge ratio (+/-) and solvent properties (pH and ionic strength) on the stability and structure of the complexes were studied. Gene expression in vitro and in vivo were studied using a luciferas<br/><br> reporter gene.Results Free DNA appeared as extended coils. Chitosan complexes had, a variety of physical shapes depending on the experimental conditions. in general, the fraction of complexes that had nonaggregated, globular structures increased with increasing chain length of the chitosan oligomer, increasing charge ratio and reduction of pH (from 6.5 to 3.5). A further increase in charge ratio for globular complexes or a further reduction in pH (to 2.5) increased the fraction of aggregates, indicating a window where pharmaceutically desirable globules are obtained. Gene transfection efficiencies in vitro and in vivo were related to the physical shape and stability of the complexes. Only the 24-mer formed stable complexes that gave a high level of gene expression comparable to that of high molecular weight ultrapure chitosan (UPC) in vitro and in vivo.Conclusions Chitosan oligomers form complexes with DNA in a structure-dependent manner. We conclude that the 24-mer, which has more desirable physical prope<br/><br> ties than UPC, is more attractive as a gene delivery system than the conventional high molecular weight chitosans. Copyright (C) 2002 John Wiley Sons, Ltd.}}, author = {{Köping-Hoggard, M and Mel'nikova, Y S and Vårum, K M and Lindman, Björn and Artursson, P}}, issn = {{1521-2254}}, language = {{eng}}, number = {{2}}, pages = {{130--141}}, publisher = {{John Wiley & Sons Inc.}}, series = {{Journal of Gene Medicine}}, title = {{Relationship between the physical shape and the efficiency of oligomeric chitosan as a gene delivery system in vitro and in vivo}}, url = {{http://dx.doi.org/10.1002/jgm.327}}, doi = {{10.1002/jgm.327}}, volume = {{5}}, year = {{2003}}, }