Algae Gene Therapy Partially Restored Completely Blind Man’s Vision – Intelligent Living

For the first time, doctors have partially restored the vision of a completely blind French man using light-sensing algae proteins. The breakthrough marks a significant milestone in genetic blindness treatment.

The man was diagnosed with the rare, genetic eye condition retinitis pigmentosa (RP) which causes the death of light-sensing cells on the retina forty years ago. The condition affects over two million people worldwide, and while complete blindness is rare, the man has had no vision for the past twenty years.

The French man, whose identity has not been revealed, was treated with optogenetics therapy, which uses the algae proteins to control cells at the back of his eye. He first realized the treatment was working when he could see the painted stripes of a crosswalk. Impressively, he can now count and grab objects too!

According to the study published on May 24 in Nature Medicine, this is the first reported case of partial functional recovery in a neurodegenerative condition after optogenetic therapy.

Optogenetics is a standard tool in fundamental neuroscience research, but its new to the world of medicine. It works by using light to activate specific brain cells and was used by the doctors in France to restore one of the mans eyes to detect light.

In his case, the light-detecting cells in his retina had died off a long time ago; therefore, the doctors inserted an algae gene into the surviving cells of the retina at the back of his eye. This caused them to produce channelrhodopsins, a protein found in algae that helps the photosynthetic microbes move toward light sources. In other words, now, when they are hit with light, they will send an electrical signal directly to the brain.

Since theres a big difference between photosynthetic algae and the human eye, the new therapy has limitations. It didnt restore the mans vision to normal levels and didnt allow him to see in color. However, they would respond to amber-colored light.

To solve this problem, the patient wore special goggles with a video camera and projector to capture the real world and translate a version in the correct wavelength onto the back of his eye, allowing him to see.

After months of training and building up high enough levels of the rhodopsins in the eye, the mans brain finally learned how to see again, starting with the white stripes of a pedestrian crossing.

Dr. Jos-Alain Sahel, who treated the patient at Pariss Institute of Vision, said:

This patient initially was a bit frustrated because it took a long time between the injection and when he started to see something. But when he started to report spontaneously that he could see the white stripes across the street, you can imagine he was very excited. We were all excited.

Not only did the patient report identifying the crosswalk, but that he could count the number of white stripes too! After more training, the patient displayed a significant improvement in daily visual activities, including detecting a mug, plate, phone, furniture in a room, or a door in a corridor, but only while using the goggles. Therefore, treatment by combining an optogenetic route with light-stimulating goggles led to a decent level of visual recovery.

While the mans eyesight isnt perfect, the difference between no vision and limited is a life-changer. The findings provide proof-of-concept that using optogenetic therapy to partially restore vision is possible, concluded Prof. Botond Roska from the University of Basel.

James Bainbridge, a retinal studies professor at the UKs UCL, said:

This exciting new technology might help people whose eyesight is very severely impaired.

Researchers are also exploring optogenetic therapy for conditions like Parkinsons disease to see whether it can improve recovery from a stroke.

In recent years, scientists have developed several approaches to restore sight. One includes correcting the genetic defects that cause RP, a challenging task since the disease has a significant number of mutations in over 71 different genes. In 2018, scientists at Oxford University in the UK completed a first gene therapy trial, improving patients vision for Choroideremia (one of the many forms of RP) by injecting a single healthy gene into their eyes. Their results were published in Nature Medicine.

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Algae Gene Therapy Partially Restored Completely Blind Man's Vision - Intelligent Living