Molecular weight-dependent genetic information transfer with disulfide-linked polyethylenimine-based nonviral vectors

Abstract

One strategy for improving gene vector properties of polyethylenimine is to facilitate individual transfection mechanism steps. This study investigates (i) improving transfection efficiency by attaching peptide nuclear localization signals (nuclear localization signals: SV40 large T antigen nuclear localization signal or C-terminus of histone H1) to polyethylenimine (10 kDa) and (ii) using disulfide linkages, which are expected to be stable during polyplex formation, but cleaved inside cells giving improved gene release. Nuclear localization signal-containing polyplexes exhibited low cytotoxicity, whereas transfection efficiency with high molecular weight plasmid DNA increased up to 3.6 times that of underivatized polyethylenimine in Neuro2A cells at higher molar ratio of polyethylenimine-nitrogen to DNA-phosphate (N/P) ratios. However, with luciferase-specific low molecular weight small interfering RNA in Neuro2A/EGFPLuc cells, nuclear localization signal-containing polyplexes with disulfide linkages caused substantial cytotoxicity at N/P ratios >15 and no consistent significant reduction in luciferase expression. Possible explanations for molecular weight-dependent differences in genetic information transfer by polyplexes containing disulfide-linked nuclear localization signals are discussed.

PEGylation of Polypropylenimine Dendrimer with Alkylcarboxylate Chain Linkage to Improve DNA Delivery and Cytotoxicity

“…Although cellular uptake of particles cannot be predicted by measuring the particle size itself, particles in the submicron size range have shown to use uptake pathways such as caveolae-mediated endocytosis or clathrin-mediated endocytosis for entering the cells [21]. Based on particle size and zeta potential measurements, nanoparticles (NPs) in this study are assumed to have a suitable size range and sufficient positive charges to bind to cell surfaces.…”

“…PPI and PPI derivatives were added to HBG buffer containing plasmid and EtBr at different weight polymer/weight plasmid ratios. Plasmid condensation by PPI or its derivatives was measured in triplicate as decreased fluorescence intensity and results are reported as mean ± SD [21].…”

A Global Review on Short Peptides: Frontiers and Perspectives

“…Peptides derived from H1 histones, protamines, ribonucleoprotein A1, and high motility group (HMG) proteins could also direct DNA to the nucleus [278,279]. NLSs have been extensively used to modify GDSs for improved transfection capability [280,281]. Due to the cationic nature of most of these peptides, some believe that the enhanced gene delivery efficiency observed with them, may be related to factors other than effective nuclear recognition [282], including better polyplex morphology and DNA binding strength.…”

Evaluation of chemical modification effects on DNA plasmid transfection efficiency of single-walled carbon nanotube–succinate– polyethylenimine conjugates as non-viral gene carriers

“…Among the polycations available for functionalizing SWNTs, PEI has the advantage of providing high densities of terminal primary amines, and it is one of the most widely used non-viral vectors for transfection studies. 18 PEI has been the subject of many chemical modification studies with alkyl groups 19 or peptides [20][21][22][23] aimed at increasing transfection efficiency while lowering cytotoxicity. In the present study, we synthesize a series of DNA nanovectors by covalent conjugation of SWNTs to PEI molecules of different molecular weights through different hydrolysable linkers.…”