Development of lipopolyplexes for gene delivery: A comparison of the effects of differing modes of targeting peptide display on the structure and transfection activities of lipopolyplexes

Abstract

The design, synthesis and formulation of non‐viral gene delivery vectors is an area of renewed research interest. Amongst the most efficient non‐viral gene delivery systems are lipopolyplexes, in which cationic peptides are co‐formulated with plasmid DNA and lipids. One advantage of lipopolyplex vectors is that they have the potential to be targeted to specific cell types by attaching peptide targeting ligands on the surface, thus increasing both the transfection efficiency and selectivity for disease targets such as cancer cells. In this paper, we have investigated two different modes of displaying cell‐specific peptide targeting ligands at the surface of lipopolyplexes. Lipopolyplexes formulated with bimodal peptides, with both receptor binding and DNA condensing sequences, were compared with lipopolyplexes with the peptide targeting ligand directly conjugated to one of the lipids. Three EGFR targeting peptide sequences were studied, together with a range of lipid formulations and maleimide lipid structures. The biophysical properties of the lipopolyplexes and their transfection efficiencies in a basal‐like breast cancer cell line were investigated using plasmid DNA bearing genes for the expression of firefly luciferase and green fluorescent protein. Fluorescence quenching experiments were also used to probe the macromolecular organisation of the peptide and pDNA components of the lipopolyplexes. We demonstrated that both approaches to lipopolyplex targeting give reasonable transfection efficiencies, and the transfection efficiency of each lipopolyplex formulation is highly dependent on the sequence of the targeting peptide. To achieve maximum therapeutic efficiency, different peptide targeting sequences and lipopolyplex architectures should be investigated for each target cell type.

Drug delivery, biodistribution and anti-EGFR activity: theragnostic nanoparticles for simultaneousin vivodelivery of tyrosine kinase inhibitors and kinase activity biosensors

“…Indeed, we have previously demonstrated that lipopolyplexes formulated with P1 effectively deliver pDNA encoding for a biosensor to HCC1954 and MDA-MB-231 breast cancer cell lines in vivo , 30 and that lipopolyplexes formulated with P1 , P2 or P3 effectively transfect HCC1954 cells in vitro . 49 …”

“…General methods for chemical synthesis and solid phase peptide synthesis, sources of chemicals, purification and analytical methods are in the ESI. † Peptides P1 , 49 P2 , 49 P3 , 49 P4 , 30 and P6 30 were synthesized according to the published literature procedures. Experimental procedures for the synthesis of 3 , 8 , 10 , S6 , P5 and 7 ; HPLC/HRMS for peptides 1 , 17 , P5 , 7 and 1 H/ 13 C NMR spectra for novel compounds can be found in the ESI.…”

“…Indeed, we have previously demonstrated that lipopolyplexes formulated with P1 effectively deliver pDNA encoding for a biosensor to HCC1954 and MDA-MB-231 breast cancer cell lines in vivo, 30 and that lipopolyplexes formulated with P1, P2 or P3 effectively transfect HCC1954 cells in vitro. 49 The major challenge to the design of these self-assembling nanoparticles was the co-encapsulation of the small molecule TKI with pDNA. Whilst several groups have developed multifunctional nanoparticles for combination therapy with small molecules and nucleic acids, [50][51][52][53][54] most of these approaches have focused on the co-delivery of siRNA, and many of the reported approaches are based on dendrimers, which have associated toxicities and result in the formation of heterogeneous mixtures.…”

Lipophilic Polyamines as Promising Components of Liposomal Gene Delivery Systems

“…The CA structure significantly affects the efficiency of NA delivery to eukaryotic cells. In recent years, many monocationic amphiphiles have been obtained [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ] that form liposomes for NA delivery. In this review, we will consider polycationic amphiphiles, which, compared to monocationic analogs, enable the more efficient transport of NAs into cells due to the formation of a system of distributed charges in the polyamine matrix and their ability to facilitate NA release from endosomes.…”

Multicompartmental Lipopolyplex as Vehicle for Antigens and Genes Delivery in Vaccine Formulations

“…Most of the vehicles called “lipopolyplexes” reported in the current literature have this basic structure [ 3 , 4 , 5 , 6 ]. This design allows the generation of particles that present similarities with a viral particle, especially their small size and organization.…”