Sugar-containing polyanions as a self-assembled coating of plasmid/polycation complexes for receptor-mediated gene delivery

A Serum‐Tolerant Hydroxyl‐Modified Polyethylenimine as Versatile Carriers of pDNA/siRNA

“…[33] As reported in earlier studies, addition of polyanions such as hyaluronate could provide a coating and serve to block the undesirable interactions between polyplexes and serum proteins, thereby improve the gene transfection efficiency of PEI/DNA polyplexes in the serum. [12,34] With the observation that PTns resulted in high transfection activity in serum-containing medium, it is reasonable to assume that the introduction of hydroxyl groups on PEI surface improved the serum tolerance by protecting the polyplexes from the negative protein interactions. Furthermore, the tolerance against the protein adsorption may assist the nucleic acid polyplexes onto cell membrane to uplift the endocytosis and gene expression.…”

Novel receptor-mediated gene delivery system comprising plasmid/protamine/sugar-containing polyanion ternary complex

“…The authors have developed novel ternary genetransfection systems, which comprise the core of plasmid/polycation complex and the outer coating of an anionic polymer [9,10]. We had synthesized a poly(ethylene glycol) (PEG) derivative having carboxylic acid side chains (PEG-C) [9].…”

“…PEG-C coating often showed obvious enhancing effect on the efficiency of the polycation-mediated gene-transfer, probably owing to a proton-sponge effect of the carboxylic groups, which would cause the disrupture of the endosomic vesicles, and facilitate the transfer of the plasmid to cytosol. More recently, we evolved new ligand-presenting ternary complex systems, making use of PEG derivatives having both carboxylic acid-and sugar-side chains (sugar-PEG-Cs) [10]. The sugar-PEG-C coated the plasmid/polycation complex exhibiting the sugar residues as a binding ligand to a specific cell line, and those bearing b-galactoside pendants expressed evident enhancing effect on the transfection of the HepG2 cells.…”

“…a-Glucoside-bearing PEG-C (Mal-PEG-C), and bgalactoside-bearing PEG-C (Lac-PEG-C) were synthesized according to the previous method [10]. Briefly; a PEG derivative having 5.6 amino-and 12.1 carboxylic acid-pendants per molecule was synthesized by the chemical modification of copoly(allyl glycidyl ether/ ethylene oxide) with a mixture of aminoethanethiol and 3-mercaptopropionic acid.…”

A review of RGD-functionalized nonviral gene delivery vectors for cancer therapy

“…The enhanced gene expression could be attributed to the decomposition of the ternary complexes by competitive dissociation of the DNA molecule from the polycation upon addition of common polyanions. 63,64 In order to endow a high stability to polymer/pDNA complexes under physiological conditions, Sakae et al synthesized an anionic PEG-mercaptosuccinic acid derivative (PEG-Suc) bearing carboxylic acid side chains (Figure 1e without RGD moiety). 65,66 It was observed that PEG-Suc could be deposited on the PEI/pDNA complexes without destroying their structures even at high conjugation ratios.…”