A team of researchers has created a biodegradable polymer delivery system that effectively carries mRNA.
Led by Professor Won Jong Kim from POSTECH’s Department of Chemistry, this research team, in partnership with the Korea Disease Control and Prevention Agency (KDCA), has developed a new delivery system based on biodegradable polymers for efficient mRNA transport. Their findings have been published in Biomaterials, a prominent international journal specializing in biomaterials.
Since the onset of the COVID-19 pandemic, the global focus on mRNA vaccines has intensified. Currently, lipid nanoparticles (LNPs) are commonly used for mRNA delivery due to their effectiveness. However, a significant drawback of LNPs is their tendency to accumulate in the liver after injection, which can lead to toxicity or cause an extreme immune reaction, potentially resulting in anaphylaxis in severe cases.
To counteract this problem, the POSTECH team investigated the use of the biodegradable polymer Poly β-amino ester (PBAE) as a substitute. PBAE has previously been employed in delivering siRNA, DNA, and mRNA, and it is known for its safe degradation within the body. In this research, the team created 55 different types of PBAE polymers and designed innovative polymer nanoparticles (PNPs) specifically for mRNA delivery.
The experiments indicated that the new polymer demonstrated superior efficiency in delivering mRNA compared to traditional LNPs. Additionally, the mRNA expression persisted for up to four weeks, which is significantly longer than the typical five-day expression observed with LNPs. Importantly, the polymer localized the mRNA expression solely at the injection site, with no expression detected in the liver, thereby alleviating toxicity worries.
Moreover, in tests assessing immune responses, the polymer successfully stimulated T-cell activity and showed comparable effectiveness to LNPs in eliciting neutralizing antibodies against the COVID-19 virus. These results underscore the potential of polymer-based delivery systems as safer and more efficient alternatives for next-generation mRNA vaccines and gene therapies.
Professor Won Jong Kim remarked, “Current LNP-based delivery systems have a brief expression period, which limits their therapeutic applications. The polymeric delivery system developed by our team extends mRNA expression up to a month, making it particularly suitable for therapeutic mRNA delivery.” He also noted the importance of this research, stating, “This work introduces a new polymer material that could replace LNPs, which are predominantly patented by foreign entities.”
This research was part of a project focused on developing innovative vaccine technology, co-led by the KDCA’s National Institute of Health and funded by the National Research Foundation of Korea under the Ministry of Science and ICT.
