Cornell Researchers Develop Safer, More Effective Lipid Nanoparticles for mRNA.

A team of researchers at Cornell University has created a promising new material that could dramatically improve the delivery and effectiveness of mRNA vaccines. By replacing a widely used but potentially problematic ingredient in lipid nanoparticles, this breakthrough may lead to safer and more efficient vaccines.

Over the past five years, mRNA vaccines have played a critical role in managing the COVID-19 pandemic, gaining widespread attention for their ability to prompt cells to produce virus-fighting proteins. A key component of these vaccines is the lipid nanoparticle—a microscopic fatty sphere that shields the fragile mRNA from degradation until it reaches target cells.

However, the conventional use of polyethylene glycol (PEG) in these nanoparticles has posed challenges. While PEG stabilizes the particles and helps them avoid immune detection, it can also provoke immune reactions in some individuals. Professor Shaoyi Jiang of Cornell’s biomedical engineering department has been working on an alternative that maintains function while reducing risk.

“The body is mostly water, and PEG contains hydrophobic elements that can trigger immune responses,” explained Jiang. He noted that many people already have antibodies against PEG due to its presence in everyday products like shampoos and toothpaste. This pre-existing immunity can increase the likelihood of vaccine-related side effects.

To address this, Jiang and his team developed lipid nanoparticles using a zwitterionic polymer called poly(carboxybetaine) (PCB). Unlike PEG, PCB is super-hydrophilic and blends more seamlessly into the body, avoiding detection by the immune system while still delivering mRNA effectively.

The study, recently published in Nature Materials, found that replacing PEG with PCB results in nanoparticles that are both stable and stealthy—ideal characteristics for vaccine delivery. The modified nanoparticles reduced unwanted immune responses without compromising the vaccine’s potency.

Jiang’s team is now collaborating with Weill Cornell Medicine, Houston Methodist Cancer Center, the Hospital for Sick Children in Toronto, and the National Cancer Institute to explore clinical applications, especially in cancer immunotherapy. Cancer vaccines require higher doses due to the immune-suppressive tumor environment, making biocompatibility even more critical.

“With infections like COVID-19, small doses can be effective, but cancer requires a much stronger immune activation,” said Jiang. “Any minor issue with PEG becomes more pronounced at these higher doses. Our PCB-based system may offer a safer alternative.”

This innovation could pave the way for next-generation mRNA vaccines that are not only more effective but also better tolerated across a broader population.

Source:https://phys.org/news/2025-05-stealthy-lipid-nanoparticles-mrna-vaccines.html

This is non-financial/medical advice and made using AI so could be wrong.