Stem Cells and Macular Degeneration

By thirdAGE

Stem cells could help in treating age-related macular degeneration (AMRD), according to new research.

The finding was reported in the journalDevelopment by a team led by Professor Gilbert Bernier of the University of Montreal and its affiliated Maisonneuve-Rosemont Hospital. ARMD is a serious eye problem caused by the loss of cones.

Bernier’s team has developed a highly effective in vitro technique for producing light sensitive retina cells from human embryonic stem cells. “Our method has the capacity to differentiate 80% of the stem cells into pure cones,” Professor Gilbert explained. “Within 45 days, the cones that we allowed to grow towards confluence spontaneously formed organized retinal tissue that was 150 microns thick. This has never been achieved before.”

In order to verify the technique, Bernier injected clusters of retinal cells into the eyes of healthy mice. The transplanted photoreceptors migrated naturally within the retina of their host. His discovery indicates that treatments could be developed for currently non-curable degenerative diseases like ARMD. “Researchers have been trying to achieve this kind of trial for years,” he said. “Thanks to our simple and effective approach, any laboratory in the world will now be able to create masses of photoreceptors. Even if there’s a long way to go before launching clinical trials, this means, in theory, that will be eventually be able to treat countless patients.”

ARMD is the greatest cause of blindness amongst people over the age of 50 and affects millions of people worldwide. And as we age, it is more and more difficult to avoid – amongst people over 80, this accelerated aging of the retina affects nearly one in four. People with ARMD gradually lose their perception of colours and details to the point that they can no longer read, write, watch television or even recognize a face.

The condition is due to the degeneration of the macula, which is the central part of the retina that enables the majority of eyesight. This degeneration is caused by the destruction of the cones and cells in the retinal pigment epithelium (RPE), a tissue that is responsible for the reparation of the visual cells in the retina and for the elimination of cells that are too worn out.