Oregon State University College of Pharmacy scientists have shown that lipid nanoparticles and messenger RNA could treat blindness associated with a rare genetic condition.
Researchers developed nanoparticles able to penetrate the neural retina and deliver mRNA to the photoreceptor cells whose proper function makes vision possible.
The study, led by OSU Associate Professor of Pharmaceutical Sciences Gaurav Sahay, Oregon State doctoral student Marco Herrera-Barrera, and Oregon Health & Science University Assistant Professor of Ophthalmology Renee Ryals, was published in Science Advances.
They showed, in research involving mice and non-human primates, that LNPs equipped with peptides were able to pass through barriers in the eye and reach the neural retina.
“We identified a novel set of peptides that can reach the back of the eye,” Sahay said. “We used these peptides to act as zip codes to deliver nanoparticles carrying genetic materials to the intended address within the eye.”
“The peptides that we have discovered can be used as targeting ligands directly conjugated to silencing RNAs, small molecules for therapeutics or as imaging probes,” Herrera-Barrera added.
Limitations of AAV gene therapy
Sahay and Ryals have received a $3.2 million grant from the National Eye Institute to continue studying lipid nanoparticles’ promise in the treatment of hereditary blindness. They will lead research into using LNPs to deliver a gene editing tool that could delete bad genes in the photoreceptor cells and replace them with correctly functioning genes.
The research aims to develop solutions for the limitations associated with adeno-associated virus (AAV), the current primary means of delivery for gene editing.
“AAV has limited packaging capacity compared to LNPs and it can prompt an immune system response,” Sahay said. “It also doesn’t do fantastically well in continuing to express the enzymes the editing tool uses as molecular scissors to make cuts in the DNA to be edited. We’re hoping to use what we’ve learned so far about LNPs to develop an improved gene editor delivery system.”
Inherited retinal degeneration (IRD) encompasses a group of disorders of varying severity and prevalence that affect one out of every few thousand people worldwide.
Image shows: Nanoparticles accumulate in neural retina, by Tetiana Korzun.
