Synthesis and Evaluation of pH-Sensitive Multifunctional Lipids for Efficient Delivery of CRISPR/Cas9 in Gene Editing

Bioconjug Chem. 2019 Mar 20;30(3):667-678. doi: 10.1021/acs.bioconjchem.8b00856. Epub 2019 Jan 18.

Abstract

CRISPR/Cas9 system is a promising approach for gene editing in gene therapy. Effective gene editing requires safe and efficient delivery of CRISPR/Cas9 system in target cells. Several new multifunctional pH-sensitive amino lipids were designed and synthesized with modification of the amino head groups for intracellular delivery of CRISPR/Cas9 system. These multifunctional pH-sensitive amino lipids exhibited structurally dependent formulation of stable nanoparticles with the DNA plasmids of CRISPR/Cas9 system with the sizes ranging from 100 to 200 nm. The amino lipid plasmid DNA nanoparticles showed pH-sensitive hemolysis with minimal hemolytic activity at pH 7.4 and increased hemolysis at acidic pH (pH = 5.5, 6.5). The nanoparticles exhibited low cytotoxicity at an N/P ratio of 10. Expression of both Cas9 and sgRNA of the CRISPR/Cas9 system was in the range from 4.4% to 33%, dependent on the lipid structure in NIH3T3-GFP cells. The amino lipids that formed stable nanoparticles with high expression of both Cas9 and sgRNA mediated high gene editing efficiency. ECO and iECO mediated more efficient gene editing than other tested lipids. ECO mediated up to 50% GFP suppression based on observations with confocal microscopy and nearly 80% reduction of GFP mRNA based on RT-PCR measurement in NIH3T3-GFP cells. The multifunctional pH-sensitive amino lipids have the potential for efficient intracellular delivery of CRISPR/Cas9 for effective gene editing.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • CRISPR-Cas Systems*
  • DNA / chemistry
  • Gene Editing*
  • Green Fluorescent Proteins / genetics
  • Hemolysis / drug effects
  • Hydrogen-Ion Concentration*
  • Lipids / chemical synthesis
  • Lipids / chemistry*
  • Lipids / pharmacology
  • Mice
  • NIH 3T3 Cells
  • Plasmids

Substances

  • Lipids
  • Green Fluorescent Proteins
  • DNA