Targeting Lipopolyplexes Using Bifunctional Peptides Incorporating Hydrophobic Spacer Amino Acids: Synthesis, Transfection, and Biophysical Studies

Pilkington-Miksa, Michael; Writer, Michele; Sarkar, Supti; Meng, Qing-Hai; Barker, Steve; Shamlou, P. Ayazi; Hailes, Helen C.; Hart, Stephen L.; Tabor, Alethea B.

doi:10.1021/bc0700943

Cited by 16 publications

(8 citation statements)

References 38 publications

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“…A synthetic gene delivery system has previously been described comprising a mixture of cationic lipid (L), an integrin-targeting peptide (P) and plasmid DNA (D) which, when combined electrostatically, forms LPD complexes with highly synergistic properties and transfection efficiencies that were orders of magnitudes higher than the equivalent lipid:DNA (LD) or peptide:DNA (PD) complexes. − Significantly LPD complexes prepared using the lipids DOTMA ( 1 ) and DOPE ( 2 ) in a 1:1 weight ratio and incorporating a targeting peptide were also able to transfect nondividing cells . Furthermore the LPD complexes exhibited low toxicity and immunogenicity when examined in vitro and in vivo. − ,, Fluorescence quenching and fluorescence correlation spectroscopy (FCS) measurements have suggested that the structure of similar integrin targeting LPD vectors possessed a tightly bound DNA–peptide core surrounded by a lipid layer from which (at least some of) the cyclic integrin domain protrudes …”

Section: Introductionmentioning

confidence: 99%

Lipopolyplex Ternary Delivery Systems Incorporating C14 Glycerol-Based Lipids

Kudsiova

Fridrich

et al. 2011

Mol. Pharmaceutics

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The structure, biophysical properties and biological behavior of lipopolyplex ternary gene delivery vectors incorporating novel C14 glycerol based lipids of varying alkyl chain geometry (containing cis, trans or alkyne double bonds) have been studied in the presence and absence of a bifunctional targeting peptide designed to both condense DNA and confer integrin-specific targeting. In vitro transfection studies in breast cancer MDA-MB-231 cells revealed that ternary formulations of lipid:peptide:DNA (LPD) complexes prepared using the aforementioned lipids possessed highly synergistic transfection activity up to 2500-fold higher than their respective lipid:DNA (LD) or peptide:DNA (PD) counterparts. Furthermore, the small structural differences in the lipid alkyl chain geometries also resulted in pronounced differences in transfection within each type of formulation, whereby the trans lipids showed best activity when formulated as LD complexes, whereas the cis lipids were superior in LPD formulations. Confocal fluorescence internalization studies using labeled components of the formulations showed both the lipid and the DNA of LD complexes to be trapped in endocytic compartments, whereas in the case of LPD complexes, the DNA was clearly released from the endosomal compartments and, together with the peptide, internalized within the cell nucleus. Physicochemical characterization of the formulations carried out by light and neutron scattering, zeta potential measurement, and negative staining electron microscopy detected major structural differences between LD and LPD complexes. Gel electrophoresis assays additionally showed differences between the individual lipids tested in each type of formulation. In conclusion, the superior transfection of the trans lipids in the LD complexes was thought to be attributed to superior DNA binding caused by a more closely matched charge distribution of the more rigid, trans lipids with the DNA. In the case of the LPD complexes, the DNA was thought to be predominantly condensed by the cationic portion of the peptide forming a central core surrounded by a lipid bilayer from which the targeting sequence partially protrudes. The more fluid, cis lipids were thought to confer better activity in this formulation due to allowing more of the targeting peptide sequence to protrude.

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Section: Introductionmentioning

confidence: 99%

Lipopolyplex Ternary Delivery Systems Incorporating C14 Glycerol-Based Lipids

Kudsiova

Fridrich

et al. 2011

Mol. Pharmaceutics

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“…Our previous results had also shown that vectors containing peptides incorporating linkers that are partly hydrophobic demonstrated improved transfection properties, which is likely due to the improved accessibility of the integrin-binding motif. 46 We also hypothesized that, by adding the cleavable linker RVRR in KG32, as is the case in peptide ME27, this would promote processing of peptide components of receptor-targeted nanocomplex formulations. RVRR peptide motifs are cleavable by the endosomal enzymes furin and cathepsin B.…”

Section: Discussionmentioning

confidence: 99%

Development of Targeted siRNA Nanocomplexes to Prevent Fibrosis in Experimental Glaucoma Filtration Surgery

et al. 2018

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RNAi induced by double-stranded small interfering RNA (siRNA) molecules has attracted great attention as a naturally occurring approach to silence gene expression with high specificity. The myocardin-related transcription factor/serum response factor (MRTF/SRF) pathway is a master regulator of cytoskeletal gene expression and, thus, represents a promising target to prevent fibrosis. A major hurdle to implementing siRNA therapies is the method of delivery, and we have, thus, optimized lipid-peptide-siRNA (LPR) nanoparticles containing MRTF-B siRNAs as a targeted approach to prevent conjunctival fibrosis. We tested 15 LPR nanoparticle formulations with different lipid compositions, surface charges, and targeting or non-targeting peptides in human conjunctival fibroblasts. In vitro, the LPR formulation of the DOTMA/DOPE lipid with the targeting peptide Y (LYR) was the most efficient in MRTF-B gene silencing and non-cytotoxic compared to the non-targeting formulation. In vivo, subconjunctival administration of LYR nanoparticles containing MRTF-B siRNAs doubled bleb survival in a pre-clinical rabbit model of glaucoma filtration surgery. Furthermore, MRTF-B LYR nanoparticles reduced the MRTF-B mRNA by 29.6% in rabbit conjunctival tissues, which led to significantly decreased conjunctival scarring with no adverse side effects. LYR-mediated delivery of siRNA shows promising results to increase bleb survival and to prevent conjunctival fibrosis after glaucoma filtration surgery.

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“…The use of these compounds in hybrid materials increases the biocompatibility of such systems and allows interactions with biological organisms, which is advantageous for bioresorbable sutures, screws or plates, tissue engineering scaffolds and drug delivery systems. [32][33][34] If amino acids are used as a modier for organo-modication of clays, they can be expected to be compatible with a protein/biopeptide matrix. When compared with a chemically synthesized modier, amino acid biosurfactants have the important advantages of biodegradability, low toxicity and various possible structures.…”

Section: Synthesis and Characterizationmentioning

confidence: 99%

“…When compared with a chemically synthesized modier, amino acid biosurfactants have the important advantages of biodegradability, low toxicity and various possible structures. [32][33][34] In this study, a Cloisite-Val organoclay was prepared via a simple and environmentally friendly ion-exchange method in aqueous solution. Our interest in applying an amino acid as a swelling agent stems from the fact that the amine group of an amino acid can provide a cation (-NH 3 + ) which can form an ionic bond with the negatively charged silicate layers of MMT as well as an electrostatic interaction and covalent bond with DNA chains for the construction of DNA-based biosensors.…”

Section: Synthesis and Characterizationmentioning

confidence: 99%