Bioreducible Lipid And Messenger RNA Nanoparticles

An effective and very fast CRISPR/Cas9 genome editing in vitro and in vivo enabling; by bioreducible lipid messenger RNA (mRNA) nanoparticle is reporting. BAMEA‐O16B, a lipid nanoparticle integrating with disulfide bonds; can efficiently deliver Cas9 mRNA and sgRNA into cells; while releasing RNA in response to the reductive intracellular environment for genome editing as fast as 24 h post mRNA delivery.

But the CRISPR/Cas9 system (clustering regularly interspacing short palindromic repeat associating protein 9); is a powerful and prominent tool for manipulating the genetic information of mammalian cells. It has dramatically simplifying genome editing procedure by using a single-guide RNA (sgRNA) to recognize target DNA; and the nuclease activity of Cas9 to introduce site-specific double-strand breaks (DSBs) at target gene loci.

Messenger RNA nanoparticles

In this study, researchers report a new approach for systematic delivery of CRISPR/Cas9 by encapsulating Cas9 mRNA; and
sgRNA simultaneously into bioreducible lipid nanoparticle for efficient and very fast genome editing in vitro and in vivo. mRNA represents a promising class of nucleic acid therapeutics that complements to DNA plasmid, in terms of decreased risk of mutagenesis, transient effects, and reduced complexity.

However, exogenous mRNA is cell impermeable; and this remains as a great barrier to the therapeutic application of mRNA, including genome editing. Moreover, mRNA is different from DNA plasmid in terms of structure and stability; which all pose additional challenges to deliver mRNA into cells.

Electrostatic interaction

The study demonstrating the use of these lipid nanoparticles as nanocarriers for Cas9/ sgRNA RNPs delivery, while their mRNA delivery and in vivo genome editing efficacy remains unknown. BAMEAO16B can encapsulate mRNA via electrostatic interaction to assemble nanoparticle; while releasing mRNA intracellularly in response to the reductive chemical signals through a disulfide bond exchange mechanism.

The research study envision the efficient knockdown of PCSK9 gene using CRISPR/Cas9 basing technology together with nonviral nanoparticle delivery system can have the potential for clinical translation. Moreover, the nanoparticle injections did not induce obvious hepatocellular injury, as revealed by the minimal change of serum aspartate transaminase (AST), alanine aminotransferase (ALT), and total bilirubin of mice with all injections.