Higher Order Architecture of Designer Peptides Forms Bioinspired 10 nm siRNA Delivery System

Abstract

The higher-order architecture observed in biological systems, like viruses, is very effective in nucleic acid transport. The replications of this system has been attempted with both synthetic and naturally occurring polymers with mixed results. Here we describe a peptide/siRNA quaternary complex that functions as an siRNA delivery system. The rational design of a peptide assembly is inspired by the viral capsids, but not derived from them. We selected the collagen peptide (COL) to provide the structural stability and the folding framework, and hybridize it with the cell penetrating peptide (CPP) that allows for effective penetration of biological barriers. The peptide/siRNA quaternary complex forms stoichiometric, 10 nm nanoparticles, that show fast cellular uptake (<30 min), effective siRNA release, and gene silencing. The complex provides capsid-like protection for siRNA against nucleases without being immunostimulatory, or cytotoxic. Our data suggests that delivery vehicles based on synthetic quaternary structures that exhibit higher-order architecture may be effective in improving delivery and release of nucleic acid cargo.

Nanotechnology‐Assisted RNA Delivery: From Nucleic Acid Therapeutics to COVID‐19 Vaccines

“…[ 22 , 26 ] More specifically, chemical modification geometries and convenient delivery systems have been proven to enhance treatment potency, cellular target specificity, and delivery efficacy, while reducing siRNA potential immunogenicity and toxicity. [ 43 , 44 , 45 ] siRNA conjugates have also been demonstrated to improve the target delivery efficiency and the higher durability of the silencing treatments. [ 46 ] Enhanced long‐term activity and organ specificity were found in siRNA conjugated with trivalent N‐acetylgalactosamine (GalNAc) therapeutics, allowing a continuous activity of RNAi for months in vitro and in vivo.…”

Redox-Responsive Disulfide Cyclic Peptides: A New Strategy for siRNA Delivery

“…15 Collagen peptides hybridized with CPPs have been found to be efficient as siRNA delivery systems. 16 Variation of stereochemical combination in the peptides has been explored to increase the gene silencing efficiency. 17 Few protein-derived sequences 18 and de novodesigned peptides 19 have also been used as siRNA carriers.…”

“…Recently, fusion peptides have been explored in siRNA delivery as a self-assembled nanocomplex . Collagen peptides hybridized with CPPs have been found to be efficient as siRNA delivery systems . Variation of stereochemical combination in the peptides has been explored to increase the gene silencing efficiency .…”