Coupling of importin beta binding peptide on plasmid DNA: transfection efficiency is increased by modification of lipoplex's physico-chemical properties

Abstract

Background: Non-viral vectors for gene transfer are less immunogenic than viral vectors but also less efficient. Significant effort has focused on enhancing non-viral gene transfer efficiency by increasing nuclear import of plasmid DNA, particularly by coupling nuclear localization peptidic sequences to plasmid DNA.

Toll-like receptor 2 promiscuity is responsible for the immunostimulatory activity of nucleic acid nanocarriers

“…In order to investigate the role of cationic lipids in the inflammatory processes induced during transfection, we studied the immunostimulatory properties of lipoplexes and liposomes made with RPR 128506, 120535 and 120525 ( Fig. 1 ), cationic lipopolyamines (LPAs) successfully used as DNA and siRNA delivery vectors [56] , [57] , [58] , [59] , [60] , [61] , whose polar head is constituted by polyamines mimicking peptide backbones linked to aliphatic hydrocarbon chains by an amide group. All three carry diC18:0 fully saturated aliphatic chains but differ in their cationic head group structure.…”

“…In order to investigate if LPAs are able to activate TLR2 even when complexed to nucleic acids, we incubated TLR2-transfected cells with lipoplexes formed by incubating RPR 120535, 120525 or 128506 with siRNA and pDNA as described in the transfection protocol [56] , [57] , [58] , [59] , [60] , [61] . As with the liposomes, lipoplexes activated NFκB when incubated with TLR2/CD14-transfected HEK293 cells.…”

“…1 ) on the inflammatory processes induced during transfection with lipoplexes. These cationic lipids were previously developed in the context of an intracellular delivery program and successfully used as DNA and siRNA delivery vectors [56] , [57] , [58] , [59] . Our results demonstrate that they all activate TLR2 and confer inflammatory properties to the corresponding lipoplexes.…”