Review Explores CRISPR Delivery Methods in Therapy

Viral delivery systems includes integrase-defective lentiviral vectors (IDLVs), adeno-associated vectors (AAVs), and virus-like particles (VLPs), and they all leverage the natural infection pathways of viruses to introduce gene-editing components into target cells. IDLVs, for example, are valued for their transient gene expression, reducing off-target risks while ensuring efficient gene delivery. And AAVs are particularly suited for in vivo applications due to their low immunogenicity and ability to persist episomally in non-dividing cells, making them ideal for tissues like the liver and brain.

The study also highlights advancements in dual-AAV systems to overcome cargo size limitations, enabling the delivery of larger gene-editing complexes such as base editors. VLPs, meanwhile, combine viral efficiency with non-viral safety by delivering transient RNA or protein payloads without integrating into the genome. While these methods are highly efficient, challenges like immunogenicity and production complexity remain.

Non-viral delivery systems, including lipid nanoparticles (LNPs), extracellular vesicles (EVs), and polymeric nanoparticles, offer an alternative with their customisability and reduced immunogenicity. LNPs have emerged as a leading method, widely used in therapeutic applications like mRNA vaccines. They enable effective delivery of CRISPR components such as mRNA or ribonucleoproteins (RNPs), particularly in liver-targeted treatments. Recent advancements in LNP composition, such as biodegradable ionisable lipids, enhance stability and reduce toxicity.

EVs, nature’s own nanoparticles, are promising for their innate immune tolerance and ability to cross biological barriers, such as the blood-brain barrier, enabling CRISPR delivery to challenging sites. Synthetic nanoparticles, including dendrimers and inorganic materials, further extend the toolkit with tuneable properties, although their clinical translation requires overcoming manufacturing and safety hurdles.

Multiple authors contributed to the review that appeared online 17 January in Molecular Therapy: Nucleic Acids.

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