BR2 cell penetrating peptide improved the transfection efficiency of modified polyethyleneimine

Abstract

Polyethyleneimine (PEI) is one of the most widely used polymers in gene delivery. Cell penetrating peptides (CPPs) are a group of peptides that can transfer materials from the membrane to the cytoplasm and nucleus. The aim of this study was to modify PEI with three different CPPs as a cationic polymer in order to investigate and compare their efficiency in gene delivery. The CPP-modified polymers were evaluated in terms of plasmid condensation, buffering capacity and number of primary amines. The prepared nanoparticles were examined for size, zeta potential, transfection efficiency and cytotoxicity in LNCAP cells. The resulting nanoparticles had a particle size between 183 and 313 nm. Measuring the zeta potential of the vectors indicated that the charge of the nanoparticles is between 21 and 25 mV. Vectors can condense plasmid in carrier-plasmid ratio of 4. Transfection results on the LNCAP cell line showed that the vector containing the BR2 peptide had the best transfection activity. In the cytotoxicity test, it was observed that vector containing CyLoP1 in carrier-plasmid ratio of 4 had the highest cell cytotoxicity. In conclusion, conjugation of CPPs to PEI due to physicochemical changes of the polymer resulted in improved transfection activity.