Trinity researchers have collaborated with University College London to develop a new gene therapy approach for the treatment of a group of rare genetic eye diseases.
Retinitis pigmentosa (RP) involves the breakdown and loss of cells in the retina, the light sensitive tissue that lines the back of the eyes and contains our photoreceptors: the rods and cones.
Early symptoms of these disorders include difficulty seeing at night, loss of peripheral vision, and eventually it can lead to blindness.
Researchers have known for some time that mutations in the RP2 gene are associated with the disorders, as this gene codes for a protein that is essential for normal vision. Yet, there are no current therapies to treat people living with a number of RP disorders.
The team’s findings were published in Stem Cell Reports today, detailing their method of using a modified common virus to deliver a normal, functioning copy of the RP2 gene into “mini retinas”. The mini retinas had been created using stem cells and contained a defective copy of the gene, simulating the RP2 disease.
Analysis showed that the mini retinas had successfully taken up the functioning RP2 gene and the production of the RP2 protein could then be seen within the mini retina. The treated mini retinas showed significant improvement, indicating a recovery from the RP disorder.
One of the main authors of the research, PhD researcher Ciara Shortall, said: “For the last 30 years there has been a lot of buzz about gene therapies and their potential for treating a huge variety of debilitating diseases and disorders, but it is really only recently that science has overcome difficulties associated with such approaches and begun to bring potential therapies far closer.”
Shortall added: “In relative terms it is now fairly easy to replace troublesome genes with functioning versions using non-harmful viruses, which is what we have done here. And while we are still some time and a lot of work away from an approved therapy it is hugely exciting to have begun a journey that could one day provide an effective treatment to rescue eyesight.”
The team at University College London was led by Professor Michael Cheetham, who said: “It is an important development that we can now reproduce so many elements of inherited disease using these mini-retinas.
“It makes it possible for us to study in detail why people go blind and try to find ways to prevent blindness. It’s exciting that the gene therapy seems to be so effective for this form of RP,” Cheetham continued.