Using a form of gene therapy that does not involve the use of modified viruses, researchers at Buffalo, Cleveland, and Oklahoma City took a major step towards making the blind see.
Scientists have described how they used a non-viral, synthetic nanoparticle carrier to improve and save the sight of mice with retinitis pigmentosa, an inherited disease characterized by progressive vision loss and eventual blindness.
"We hope the results of our study will be instrumental in generating a cure for the debilitating blindness associated with retinitis pigmentosa and other inherited and acquired retinal diseases. Compacted DNA nanoparticles are an exciting treatment strategy for these diseases and we look forward to exciting new developments," said Dr. Muna I. Naash.
To accomplish the feat, the researchers used groups of mice with the retinal degeneration slow (Rds) gene, which causes retinitis pigmentosa.
The mice received one of three types of "treatments"- nanoparticles containing the normal copy of the Rds gene, the normal gene alone, or saline solution.
After these treatments were delivered to the mice, the structure and function of the retina were analysed by comparing them to untreated mice with retinitis pigmentosa and healthy mice with the normal Rds gene.
Researchers also measured the level and pattern of Rds gene expression, as well as functional, structural and biochemical improvements in disease symptoms.
It was found that mice receiving the nanoparticle gene therapy show significant signs of healing.
The mice had structural improvement in their retinas, as well as functional vision improvements, which lasted throughout the duration of the study.
The mice that received the gene alone or saline continued to lose their vision.
The nanoparticles were safe and well-tolerated with no adverse effects.
"Making the blind see was once called a miracle. As we have expanded our understanding of evolution, genetics, and nanotechnology, chances are that "miraculous" cures will become as commonplace as those claimed by faith-healers past and present," said Dr. Gerald Weissmann.
The study has been published in the latest issue of The FASEB Journal.