Study Shows Lipid Nanoparticles Can Deliver Gene Therapy to Spinal Cord Injuries via Disrupted Blood Barrier
Researchers found that intravenously administered mRNA-lipid nanoparticles can cross the disrupted blood-spinal cord barrier following acute spinal cord injury in rats, achieving local gene expression in the injured tissue. The blood-spinal cord barrier, normally impermeable, becomes transiently disrupted after trauma, creating a window for systemic drug delivery. This approach could offer a less invasive alternative to direct intraspinal injection for delivering therapeutic proteins to the injured spinal cord.
A study published on bioRxiv demonstrates that mRNA-loaded lipid nanoparticles (LNPs), delivered intravenously within 6 hours of spinal cord injury in rats, can exploit the transient disruption of the blood-spinal cord barrier to achieve local transgene expression at the injury site. Transgene expression was detected in multiple cell types, including astrocytes, oligodendrocytes, microglia, and neurons, appearing within 3 hours of administration and remaining elevated for up to 5 days post-injury. The approach is motivated by the limitations of therapeutic cytokines and growth factors, which have short half-lives and currently require invasive intraspinal delivery in preclinical settings. mRNA-LNP delivery enables transient, controlled protein production without the need for surgical intervention. The findings suggest a potential therapeutic window in the acute phase of spinal cord injury during which systemic nanoparticle delivery could be leveraged for localized gene therapy.
What's missing
The study is a preprint and has not yet undergone peer review. Key limitations include that results are from a rat model only, and it is unclear how well the 6-hour therapeutic window and barrier disruption dynamics translate to human spinal cord injury. The study used reporter mRNA rather than therapeutic mRNA, so efficacy of actual therapeutic payloads remains undemonstrated. Long-term safety and functional outcomes were not assessed.
What different sources said
- bioRxivCenter
Intravenously Delivered Lipid Nanoparticles Access Acute Spinal Cord Injury via Disrupted Vasculature
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