Evaluation and optimization of chitosan derivatives-based gene delivery system via kidney epithelial cells

Non-viral vectors have been widely proposed as safer alternatives to viral vectors, and cationic polymers have gained increasing attention because they can form self-assembly with DNA. Chitosan is also considered to be a good candidate for gene delivery systems, since it is already known as a biocompatible, biodegradable, and low toxic material with high cationic potential. However, low solubility and transfection efficiency need to be overcome prior to clinical trial. In this work, we focus on alkyl modified chitosan which might be useful in DNA condensing and efficient gene delivery.

N, N- Diethyl N- Methyl (DEMC) and N- Triethyl Chitosan (TEC) were synthesized from chitosan polymer. In order to optimize the polymers for gene delivery, we used FITC-dextran (FD). Then the optimized polymer concentrations were used for gene delivery. Fluorescent microscope was used, in order to evaluate the polymers' efficiency for gene delivery to human embryonic kidney epithelial cells (HEK 293T).

This modification increased chitosan's positive charge, thus these chitosan derivatives spontaneously formed complexes with FD, green fluorescence protein plasmid DNA (pEGFP), red fluorescence protein plasmid DNA (pJred) and fluorescent labeled miRNA .RESULTS gained from fluorescent microscope showed that TEC and DEMC were able to transfer FD, DNA and miRNA (micro RNA) to HEK cell line.

We conclude that these chitosan derivatives present suitable characteristics to be used as non-viral gene delivery vectors to epithelial cells.