Gene Therapy Delivery Improved: New Nanoparticles Enhance Efficiency | Nature Biotechnology

Gene-based therapies, holding immense promise for treating a range of diseases, are on the cusp of a significant leap forward thanks to research from Oregon State University. Scientists have developed a new method to track the delivery of genetic material within cells, overcoming a major hurdle in ensuring these therapies reach their intended targets and function effectively. This breakthrough addresses a longstanding challenge: getting therapeutic genes to the right location *inside* cells, where they can exert their beneficial effects, rather than being broken down as cellular waste.

Tracking Genetic Cargo: A New DNA Barcoding System

The study, published today in Nature Biotechnology, details a “DNA barcoding” test developed by researchers led by Oregon State University College of Pharmacy graduate student Antony Jozić, under the guidance of Professor Gaurav Sahay. This innovative system allows scientists, for the first time, to measure in living organisms which gene-carrying nanoparticles successfully avoid cellular “trash compactors” – lysosomes – and reach their functional destination. Lysosomes are essential for cellular housekeeping, breaking down unwanted materials, but they can too dismantle therapeutic genetic material before it has a chance to work. Phys.org reports on the study’s findings.

“Once you can measure something, you can design around it,” explains Sahay. The ability to quantify the efficiency of different nanoparticle designs in delivering their genetic cargo has paved the way for the creation of new, more effective lipid nanoparticles.

What are Lipid Nanoparticles?

Lipid nanoparticles (LNPs) are tiny spheres composed of fatty acids and similar organic compounds. They act as delivery vehicles, encapsulating genetic material – like RNA or DNA – and transporting it into cells. The effectiveness of LNPs hinges on their ability to both protect the genetic material and release it within the cell in the correct location. A key component of these particles is an “ionizable lipid,” which can change its electrical charge depending on the acidity of its surroundings. This property is crucial for both packaging the genetic material and interacting with cell membranes.

Improving Delivery Efficiency with Ionizable Lipids

The research team, collaborating with scientists from OHSU, Tennessee Technological University, Yeungnam University in South Korea, and the University of Brest in France, used the DNA barcoding system to identify and validate a new class of lipid nanoparticles built around improved ionizable lipid systems. These new particles demonstrated a significantly higher rate of successful gene delivery, and importantly, at lower doses than currently used advanced delivery methods. This reduction in dosage is a critical step towards minimizing potential side effects associated with gene therapies.

The study highlighted that the primary challenge in gene therapy isn’t necessarily getting the nanoparticles *into* cells, but rather ensuring the genetic cargo reaches the correct cellular compartment once inside. This insight provides a clear roadmap for improving RNA and gene-editing medicines and reducing unintended effects – often referred to as “off-target effects.” Nature details the assay used to identify these mechanisms.

Implications for Gene Editing and RNA Therapies

This research has broad implications for the field of gene-based therapies, encompassing both gene editing technologies like CRISPR and RNA-based therapies. Gene editing involves making precise changes to an individual’s DNA to correct genetic defects, while RNA therapies aim to regulate gene expression – essentially controlling how genes are used by the body. Both approaches rely on efficient and targeted delivery of genetic material to cells.

The development of more efficient LNPs could potentially expand the range of diseases that can be treated with gene therapies, making these innovative treatments accessible to a wider population. Currently, gene therapies are often limited by their high cost and the complexity of manufacturing and delivery. Improving delivery efficiency could help to reduce these barriers.

What’s Next: Refining Delivery and Expanding Applications

The research team is now focused on further refining the design of lipid nanoparticles and exploring their potential for delivering a wider range of genetic materials. They are also investigating the long-term effects of these new nanoparticles and assessing their safety profile in more complex animal models. Sahay notes that publication in Nature Biotechnology validates the drug delivery science being developed within Oregon State University’s collaborative research environment.

Further research will also focus on tailoring LNPs to specific tissues and cell types, maximizing their effectiveness for different diseases. The team’s collaboration with Paul-Alain Jaffrès and his graduate student Chole Le Roux at the University of Brest in France was instrumental in creating some of the most potent ionizable lipids reported to date. BIOENGINEER.ORG provides additional details on the collaborative effort.

The National Institutes of Health, the Defense Advanced Research Projects Agency, and the M.J. Murdock Charitable Trust provided funding for this research, highlighting the broad recognition of its potential impact. As the field of gene therapy continues to evolve, advancements like these are crucial for translating the promise of genetic medicine into tangible benefits for patients.