pH-Sensitive Chitosan–Heparin Nanoparticles for Effective Delivery of Genetic Drugs into Epithelial Cells

Abstract

Chitosan has been extensively studied as a genetic drug delivery platform. However, its efficiency is limited by the strength of DNA and RNA binding. Expecting a reduced binding strength of cargo with chitosan, we proposed including heparin as a competing polyanion in the polyplexes. We developed chitosan–heparin nanoparticles by a one-step process for the local delivery of oligonucleotides. The size of the polyplexes was dependent on the mass ratio of polycation to polyanion. The mechanism of oligonucleotide release was pH-dependent and associated with polyplex swelling and collapse of the polysaccharide network. Inclusion of heparin enhanced the oligonucleotide release from the chitosan-based polyplexes. Furthermore, heparin reduced the toxicity of polyplexes in the cultured cells. The cell uptake of chitosan–heparin polyplexes was equal to that of chitosan polyplexes, but heparin increased the transfection efficiency of the polyplexes two-fold. The application of chitosan–heparin small interfering RNA (siRNA) targeted to vascular endothelial growth factor (VEGF) silencing of ARPE-19 cells was 25% higher. Overall, chitosan–heparin polyplexes showed a significant improvement of gene release inside the cells, transfection, and gene silencing efficiency in vitro, suggesting that this fundamental strategy can further improve the transfection efficiency with application of non-viral vectors.

Progress in the Development of Chitosan-Based Biomaterials for Tissue Engineering and Regenerative Medicine

“…For example, heparin is widely used with CS polyelectrolyte complex due to its ability to bind growth factors and cytokines [113][114][115][116][117]. In a recent study, CS-heparin NPs were used for the delivery of siRNA against vascular endothelial growth factor in human retinal epithelial cells (ARPE-19) with a 2-fold higher transfection efficiency in comparison to carrying plasmid DNA alone [118]. In addition to gene delivery, CS could be modified to deliver growth factors and cytokines [119].…”

Niosome-Based Approach for In Situ Gene Delivery to Retina and Brain Cortex as Immune-Privileged Tissues

“…Most of those cationic polymers include chitosans [55], polyethylenimine [56], or poly (L-lysine) [57]. Moreover, hybrid compounds, made by a combination of both polycationic and polyanionic polymers, and with different organic and inorganic materials such as polymers, magnetite, or lipids can be used also to deliver genetic material for different purposes [58][59][60][61][62].…”

Photosensitive Poly-l-lysine/Heparin Interpolyelectrolyte Complexes for Delivery of Genetic Drugs

“…Moreover, they provide the compaction of DNA, similarly to that in chromosome, which result in protection of genetic construction from degradation and possibility of internalization into the cells [24]. There are a number of polycations, which showed interesting properties as gene delivery vehicles [20], among which poly(ethyleneimine) [25,26], poly-l-lysine (PLL) [22,27,28] and chitosan [29,30] are the most studied ones. The high charge density of polycations, improved the binding of DNA and cell penetration, but could not provide the effective intracellular unpacking of genetic construction to release in cytoplasm and affect the inner biochemistry of cells [21,30,31].…”

“…The high charge density of polycations, improved the binding of DNA and cell penetration, but could not provide the effective intracellular unpacking of genetic construction to release in cytoplasm and affect the inner biochemistry of cells [21,30,31]. In order to diminish this effect, different polyanions were considered as a competitive counter-ions [29,32,33]. In our recent research, we have enhanced the transfection of pEGFP and anti-VEGF siRNA with chitosan by addition of heparin as a competitive polyanion [29].…”

“…In order to diminish this effect, different polyanions were considered as a competitive counter-ions [29,32,33]. In our recent research, we have enhanced the transfection of pEGFP and anti-VEGF siRNA with chitosan by addition of heparin as a competitive polyanion [29]. Other approaches include the application of polycations covalently modified by polyanions to enhance gene delivery efficacy [26,34].…”