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New methodologies to characterize the effectiveness of the gene transfer mediated by DNA-chitosan nanoparticles.

Centelles MN, Qian C, Campanero MA, Irache JM - Int J Nanomedicine (2008)

Bottom Line: No significant influence of MW was observed on the levels of luciferase expression.Nevertheless, the same administration procedure of the three formulations did not improve the levels of transgene expression obtained with naked DNA.This fact could be explained by the rapid physiological turn-over of enterocytes and by the ability of chitosan nanoparticles to control the DNA release.

View Article: PubMed Central - PubMed

Affiliation: Centro Galénico, Departamento Farmacia y Tecnología Farmacéutica, University of Navarra, Pamplona, Spain.

ABSTRACT
In this work three DNA-chitosan nanoparticle formulations (Np), differing in the molecular weight (MW; 150 kDa, 400 kDa, and 600 kDa) of the polysaccharide, were prepared and administered by two different administration routes: the hydrodynamics-based procedure and the intraduodenal injection. After the hydrodynamic injection, DNA-chitosan nanoparticles were predominantly accumulated in the liver, where the transgene was expressed during at least 105 days. No significant influence of MW was observed on the levels of luciferase expression. The curves of bioluminescence versus time obtained using the charge-coupled device (CCD) camera were described and divided in three phases: (i) the initial phase, (ii) the sustained release step and (iii) the decline phase (promotor inactivation, immunological and physiological processes). From these curves, which describe the transgene expression profile, the behavior of the different formulations as gene delivery systems was characterized. Therefore, the following parameters such as C(max) (maximum level of detected bioluminescence), AUC (area under the bioluminescence-time curve) and MET (mean time of the transgene expression) were calculated. This approach offers the possibility of studying and comparing transgene expression kinetics among a wide variety of gene delivery systems. Finally, the intraduodenal administration of naked DNA permitted the gene transfer in a dose dependent manner quantifiable with the CCD camera within 3 days. Nevertheless, the same administration procedure of the three formulations did not improve the levels of transgene expression obtained with naked DNA. This fact could be explained by the rapid physiological turn-over of enterocytes and by the ability of chitosan nanoparticles to control the DNA release.

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Evolution of the luciferase expression in the intestine over the time.Notes: Data express the mean ± standard deviation (n = 4).
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f5-ijn-3-451: Evolution of the luciferase expression in the intestine over the time.Notes: Data express the mean ± standard deviation (n = 4).

Mentions: Bioluminescence monitorized by the CCD camera gave some evidence regarding the intensity of the transgene expression phenomenon over time (localization and quantification). Interestingly, after direct injection of naked DNA in the intestinal lumen, transgene expression could be detected and quantified in the intestine in a dose dependent manner (Figure 4B). This expression reached its maximum point at 24 h and quickly decreased to become hardly detectable after 72 h. These results correlate with the enterocytes’ lifetime determined by Ferraris and colleagues (1992). In the same way, the three different formulations were administered without any further modification after the coacervation process. Luciferase expression could be also followed within 3 days (Figure 5).


New methodologies to characterize the effectiveness of the gene transfer mediated by DNA-chitosan nanoparticles.

Centelles MN, Qian C, Campanero MA, Irache JM - Int J Nanomedicine (2008)

Evolution of the luciferase expression in the intestine over the time.Notes: Data express the mean ± standard deviation (n = 4).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2636586&req=5

f5-ijn-3-451: Evolution of the luciferase expression in the intestine over the time.Notes: Data express the mean ± standard deviation (n = 4).
Mentions: Bioluminescence monitorized by the CCD camera gave some evidence regarding the intensity of the transgene expression phenomenon over time (localization and quantification). Interestingly, after direct injection of naked DNA in the intestinal lumen, transgene expression could be detected and quantified in the intestine in a dose dependent manner (Figure 4B). This expression reached its maximum point at 24 h and quickly decreased to become hardly detectable after 72 h. These results correlate with the enterocytes’ lifetime determined by Ferraris and colleagues (1992). In the same way, the three different formulations were administered without any further modification after the coacervation process. Luciferase expression could be also followed within 3 days (Figure 5).

Bottom Line: No significant influence of MW was observed on the levels of luciferase expression.Nevertheless, the same administration procedure of the three formulations did not improve the levels of transgene expression obtained with naked DNA.This fact could be explained by the rapid physiological turn-over of enterocytes and by the ability of chitosan nanoparticles to control the DNA release.

View Article: PubMed Central - PubMed

Affiliation: Centro Galénico, Departamento Farmacia y Tecnología Farmacéutica, University of Navarra, Pamplona, Spain.

ABSTRACT
In this work three DNA-chitosan nanoparticle formulations (Np), differing in the molecular weight (MW; 150 kDa, 400 kDa, and 600 kDa) of the polysaccharide, were prepared and administered by two different administration routes: the hydrodynamics-based procedure and the intraduodenal injection. After the hydrodynamic injection, DNA-chitosan nanoparticles were predominantly accumulated in the liver, where the transgene was expressed during at least 105 days. No significant influence of MW was observed on the levels of luciferase expression. The curves of bioluminescence versus time obtained using the charge-coupled device (CCD) camera were described and divided in three phases: (i) the initial phase, (ii) the sustained release step and (iii) the decline phase (promotor inactivation, immunological and physiological processes). From these curves, which describe the transgene expression profile, the behavior of the different formulations as gene delivery systems was characterized. Therefore, the following parameters such as C(max) (maximum level of detected bioluminescence), AUC (area under the bioluminescence-time curve) and MET (mean time of the transgene expression) were calculated. This approach offers the possibility of studying and comparing transgene expression kinetics among a wide variety of gene delivery systems. Finally, the intraduodenal administration of naked DNA permitted the gene transfer in a dose dependent manner quantifiable with the CCD camera within 3 days. Nevertheless, the same administration procedure of the three formulations did not improve the levels of transgene expression obtained with naked DNA. This fact could be explained by the rapid physiological turn-over of enterocytes and by the ability of chitosan nanoparticles to control the DNA release.

Show MeSH