Safe vectors
A multidisciplinary team from the University of South Wales in Sydney has discovered that liposomes, commonly used in pharmacology to encapsulate drugs or genes, can release a load in a certain area of the body under the influence of light. The results were demonstrated on cell lines and animal models.
CRISPR gene therapy technology, in which the guide RNA looks for defective genes, and the Cas9 protein cuts it out and replaces it with a healthy one, is usually delivered by weakened viruses that move around the body in search of a target cell.
And although the technology is recognized as revolutionary – this year the researchers who developed it were awarded the Nobel Prize in Chemistry – the use of viruses as a means of delivery has drawbacks, including uncontrolled immune response and toxicity.
Liposomes are a safer option
In this study, the group demonstrated that it is possible to use a much safer carrier for the CRISPR system, which will release it exclusively in the area of the body that needs editing.
The researchers used liposomes – spherical nanostructures of fat molecules, very similar to the material of cell membranes. They have already proven themselves to be an effective drug delivery system, as they are relatively easy to prepare and fill with appropriate medicines.
In addition, they are much safer than weakened viruses.
Liposomes can be "turned on" with the help of light: when light hits the liposomes, they immediately break down and release the payload.
On cell lines and in vivo on danio fish, researchers have shown that under the influence of an LED lamp, liposomes throw out their contents – CRISPR tools that begin to work in search of genes of interest. Light can activate liposomes up to a centimeter below the surface of the skin.
Deep Tissue Treatment
But what if the problem area is a deeply located tumor? The authors claim that X-rays can be used instead of light for the same effect. Past studies have already confirmed that liposomes can be activated by X-rays. The next step will be to create a suitable animal model that could be used to test this technology for the treatment of deep-localization cancer.
Article by Y.A.Aksoy et al. Spatial and Temporal Control of CRISPR-Cas9-Mediated Gene Editing Delivered via a Light-Triggered Liposome System is published in the journal ACS Applied Materials and Interfaces.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on UNSW materials: Light, liposomes, action: researchers show safer, more targeted way to deliver CRISPR gene therapy.