French people who have been completely blind in the past 40 years in Pittsburgh can now process some visual information with the help of treatment techniques developed by researchers at the University of Pittsburgh.

This breakthrough marks the first ever partial recovery of vision in a blind patient.

Groundbreaking research, published in the journal this week Natural medicineRelying on an experimental method called optogenetic therapy. Pitt’s scientists collaborated with colleagues in Switzerland and France to demonstrate to a 58-year-old patient with progressive neurodegenerative disease retinitis pigmentosa.

“I hope this will be a major breakthrough,” Say José-Alain Sahel, director of the Department of Ophthalmology at the University of Pittsburgh and director of the UPMC Eye Center. “This article is the culmination of more than 12 years of work, and I am very pleased to be able to contribute to this work with Botond Roska in Basel and all my colleagues at the Institute of Vision in Paris.”

Retinitis pigmentosa destroys the light-sensitive cells on the retina. These light-sensitive cells usually help transmit nerve impulses through the optic nerve to the brain to form the image we see. The disease causes mutations in more than 71 different genes, making most gene therapies impractical and ineffective.

Sahel said: “The eye is a very complex system that allows our vision to adapt to different levels of light.” “But the complex system is very fragile-so when the vision disappears, in addition to using a prosthesis or reactivating the retina Outside of the remaining cells, there is almost no other treatment.”

Optogenetic therapy does not directly fix all the mutated genes in the patient, but directly activates the nerve cells in the retina. It relies on the use of proteins found in luminescent algae, which change its shape in response to light. This enables photoreceptor cells to detect the flow of light information and transmit the signal to the nerve endings of the brain.

In order to make this method clinically feasible, scientists have to find an optimal position in the color spectrum. These proteins are not sensitive enough to process images under ordinary light, but excessively bright and magnified light (such as blue spectrum light) may damage the retina or narrow the pupils.

Researchers started using proteins that only perceive amber light. By injecting the amber photoprotein-carrying virus into the eyes of patients with poor vision, they can trigger the movement of the eyes to detect ganglion cells, which receive light signals from the photoreceptors and send them to the optic nerve and brain.

The last part of the puzzle is to develop a pair of goggles that can collect light pixels from the world and transmit them to the eye as a single wavelength in the amber spectrum. The goggles are equipped with a camera that can detect changes in light intensity pixel by pixel and record them as different events. These light events captured by the camera will then be projected onto the retina in real time as real-time pulses.

As New York Times According to reports this week, the research team plans to recruit blind volunteers to try their optogenetic treatments before the coronavirus pandemic. It is believed that it may take several months for the brain to learn to process information from the goggles.

The pandemic reduced the number of volunteer programs, and French patients were the only ones participating in the experimental treatment.

But when the research team was able to talk to the patient about the changes he experienced and perform other tests with him, the results became clear.

Sahel said: “It takes time to adjust the use of glasses.” “At first, the patient did not find the glasses very useful, but a few months later, he began to see white stripes on the crosswalk. After several trainings, he was able to recognize the size. Different other objects.”

In the laboratory, researchers found that patients can reach out and touch the laptop, or count objects placed in front of him with relative accuracy. The change in vision is not dramatic, and still limited to a small area, the definition is vague and short-lived, but it represents a leap in the concept that can be used to treat certain forms of blindness.

The next step in optogenetic therapy will be to test other volunteers and conduct larger-scale clinical trials to determine the effectiveness of this new method. It has long been a scientific model for animal experiment testing and basic research, and can become the basis of a breakthrough method that can restore certain functional vision to the blind.