A Novel Peptide-Equipped Exosomes Platform for Delivery of Antisense Oligonucleotides

Abstract

Exosomes are natural delivery vehicles because of their original feature such as low immunogenicity, excellent biocompatibility, and migration capability. Engineering exosomes with appropriate ligands are effective approaches to improve the low cellular uptake efficiency of exosomes. However, current strategies face considerable challenges due to the tedious and labor-intensive operational process. Here, we designed a novel peptides-equipped exosomes platform which can be assembled under convenient and mild reaction condition. Cell-penetrating peptides (CPPs) was conjugated on HepG2 cells-derived exosomes surface which can not only enhance the penetrating capacity of exosomes but also assist exosomes in loading antisense oligonucleotides (ASOs). The cellular uptake mechanism was investigated and we compared the difference between natural exosomes and modified exosomes. The resulting nanosystem demonstrated a preferential tropism for cells that are parented to their source tumor cells and could remarkably increase the cellular delivery of G3139 with efficient downregulation of antiapoptotic Bcl-2. This work developed a rapid strategy for intracellular delivery of nucleic acids, thus providing more possibilities toward personalized cancer medicine.

A self-assembling peptidic platform to boost the cellular uptake and nuclear delivery of oligonucleotides

“…In a recent study, cell penetrating peptide (CPP) conjugated exosomes (EXOs) were used as a platform for ASO delivery. 53 Their western blot analysis revealed a decrease of 51.71% and 69.69% in BCL-2 levels by EXO-G3139 and EXO-R9-G3139 in HepG2 cells. In another example, a 70% downregulation in Bcl-2 mRNA was found in MCF-7 cells incubated with self-assembled peptide nanofibers for G3139 delivery.…”

“…Conceivably, this reduction is caused by G3139-GAP delivery since G3139 ASO was shown to reduce Bcl-2 expression which was associated with apoptosis and a decrease in cell proliferation. [51][52][53][54] Whereas scrambled oligo loaded NLS-MCMs had no toxic effects (Fig. 3), using lipofectamine reagent to transfect scrambled oligonucleotides revealed a 20 ± 3% decrease in cell viability after 48 h (Fig.…”

Exosomes as Emerging Drug Delivery and Diagnostic Modality for Breast Cancer: Recent Advances in Isolation and Application

“…Antisense oligonucleotide-loaded exosomes showed enhanced HepG2 cell uptake as compared to the free oligonucleotide. It is worth mentioning that exosomes also possess an ability to bypass the blood-brain barrier (BBB), hence, exosomes can also be used to deliver entrapped therapeutic moieties to the CNS which may be a good opportunity to target the breast cancer metastasized to the brain [109]. In another study, Lee et al, 2011 overexpressed the major histocompatibility complex (MHC) class II protein in murine melanoma cell lines (B16F1) by transduction of the CIITA (Class II transactivator) gene.…”

Cellular Crosstalk in the Vascular Wall Microenvironment: The Role of Exosomes in Vascular Calcification

“…In addition, inherent homing ability of exosomes suggests their potential utility in drug delivery ( 126 , 127 ). Specifically, exosomes surface could easily be modified, by conjugated with a cell or tissue specific aptamer and cell penetrating peptide which accomplish the goal of precision treatment ( 128 , 129 ). However, using exosomes as nano-drug delivery implements is currently unable to achieve since its low rate of drug encapsulation ( 125 , 130 ), how to engineer exosomes so that they are stably expressed once introduced into the recipient body and to avoid off-target effects are important issues to resolve.…”