کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7697 560 2011 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Excess polycation mediates efficient chitosan-based gene transfer by promoting lysosomal release of the polyplexes
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بیو مهندسی (مهندسی زیستی)
پیش نمایش صفحه اول مقاله
Excess polycation mediates efficient chitosan-based gene transfer by promoting lysosomal release of the polyplexes
چکیده انگلیسی

The optimal ratio of the polycation’s amine to DNA phosphate group (N:P) for efficient polymer-based transfection always employs excess polycation versus DNA. Most of the excess polycation remains free in solution, unassociated with the polyplexes, but is essential for efficient transfection. The mechanism by which excess polycation increases transfection efficiency is not identified. We hypothesised that excess chitosan facilitates intracellular lysosomal escape of the polyplexes. We highlight here the essential role of excess chitosan by rescuing poorly transfecting low N:P ratio polyplexes, by adding free chitosan before or after polyplex addition to cells. We examined polyplex uptake, the kinetics of rescue, intracellular trafficking, and the effects of lysosomotropic agents. We found the facilitating role of excess chitosan to be downstream of cellular uptake. Live-cell confocal quantification of intracellular trafficking revealed prolonged colocalisation of low N:P polyplexes within lysosomes, compared to shorter residence times for both rescued or N:P 5 samples, followed by observation of free pDNA in the cytosol. These data demonstrate that excess polycation mediates enhanced transfection efficiency by promoting the release of polyplexes from the endo-lysosomal vesicles, revealing a critical intracellular barrier overcome by excess polycation and suggesting possible avenues for further optimisation of polymer-based gene delivery.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biomaterials - Volume 32, Issue 20, July 2011, Pages 4639–4646
نویسندگان
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