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bioRxiv · 10.1101/2022.12.18.518592

Poly(2-oxazoline)-based polyplexes as a PEG-free plasmid DNA delivery platform

Abstract

The present study expands the versatility of cationic poly(2-oxazoline) (POx) copolymers as a PEG-free platform for gene delivery to immune cells, such as monocytes and macrophages. Several block copolymers are developed by varying non-ionic hydrophilic blocks (poly(2-methyl-2-oxazoline) (pMeOx) or poly(2-ethyl-2-oxazoline) (pEtOx), cationic blocks, and an optional hydrophobic block (poly(2-isopropyl-2-oxazoline) (iPrOx). The cationic blocks are produced by side chain modification of 2-methoxy-carboxyethyl-2-oxazoline (MestOx) block precursor with diethylenetriamine (DET) or tris(2-aminoethyl)amine (TREN). For the attachment of a targeting ligand, mannose, we employed azide-alkyne cycloaddition click chemistry methods. Of the two cationic side chains, polyplexes made with DET-containing copolymers transfect macrophages significantly better than those made with TREN-based copolymer. Likewise, non-targeted pEtOx-based diblock copolymer is more active in cell transfection than pMeOx-based copolymer. The triblock copolymer with hydrophobic block iPrOx performs poorly compared to the diblock copolymer which lacks this additional block. Surprisingly, attachment of a mannose ligand to either of these copolymers is inhibitory for transfection. Despite similarities in size and design, mannosylated polyplexes result in lower cell internalization compared to non-mannosylated polyplexes. Thus, PEG-free, non-targeted DET- and pEtOx-based diblock copolymer outperforms other studied structures in the transfection of macrophages and displays transfection levels comparable to GeneJuice, a commercial non-lipid transfection reagent.

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BibTeXRIS

Yamaleyeva, D., Makita, N., Hwang, D., Haney, M., Jordan, R., Kabanov, A. V.. 2022-12-18. Poly(2-oxazoline)-based polyplexes as a PEG-free plasmid DNA delivery platform. https://doi.org/10.1101/2022.12.18.518592

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