Macular Degeneration is a huge concern because it is the leading cause of blindness in an aging population over the age of 50. The problem is that this age bracket is increasing dramatically in numbers and no cure exists.
Macular Degeneration (or ARMD) comes in two forms: Dry and Wet.
Most of the current research has been directed towards the Wet form. Even though it represents only 10% of the macular degeneration patients, it causes significantly more severe vision loss. If one has the wet form of macular degeneration, the best drugs to treat this are called anti-VEGFs. These drugs, such as Lucentis and Eyelea, currently have to be injected into the eye as often as every month. While they don't cure you of the disease, they are very effective at preventing it from getting worse. The trouble is, you have to keep getting them and you don't tend to see much improvement, as their main effect is to prevent progression.
While the current treatment is very effective at stabilising the disease, more and more research has been directed towards the inconvenience and significant cost of having to front up every month to try and preserve vision.
What about the Dry form of macular degeneration?
Even though Dry Macular Degeneration usually does not lead to severe vision loss like the Wet form, it is still responsible for significant problems in some people. As Dry Macular Degeneration progresses it can develop into a condition called Geographic Atrophy (with associated vision loss) or it can progress to the Wet Form and its associated problems.
The bottom line is, other than recommending weight loss, cessation of smoking, better diet, exercise and specific vitamin and antioxidant supplements, Dry Macular degeneration runs its course. Maybe by implementing the above interventions we are able to slow the process down.
Stem cells for macular degeneration
Stem cell options for ARMD have been in the pipeline for the past 4 years, with several clinical trials taking place around the world. As it progresses, Dry Macular Degeneration, destroys a layer of the retina called the Retinal Pigment Epithelium (RPE). It makes sense that if we could transplant a new Retinal Pigment Epithelium layer, maybe the macula could be regenerated again and prolong vision.
Japanese researchers led by ophthalmologist Masayo Takahashi, have transformed skin cells into induced pluripotent stem cells (iPS cells) which can then become any kind of cell, including retinal pigment epithelium cells. In 2014, these cells were transplanted into monkeys and mice. Because the cells were developed from the animals' own tissue, they did not provoke an immune reaction which would cause them to be rejected. The animal studies also showed that the cells did not appear to cause tumours to develop.
Human trials began in 2014, just days after clearance was given to proceed. A 70 year old Japanese woman became the first person to be treated for macular degeneration with induced pluripotent stem (iPS) cells. Since then, a number of small clinical trials have begun across the world, in the UK, the USA, Brazil and Korea, as well as Japan.
The above image is a group of stem cells that can be caused to differentiate into RPE cells for the macula.
Is it safe?
Early human tests are usually performed on blind eyes that have no visual potential. This is done so that if unexpected outcomes occur, at least the eyes were blind anyway.
What is always a little scary is that if tumours are formed, could they possibly spread to the rest of the body. Where the person only had an eye problem, now could possibly be risking their life! It has been demonstrated though, that tumours are highly unlikely to result from cells being transplanted in to the eye.
Progression in science occasionally comes with significant risk. Unless these risks are taken science could not possibly progress.
Worried about Macular Degeneration? At The Eye Practice, we take a proactive approach to macular health. Call (02) 9290 1899 or make an appointment online today.
This post was originally published in Dec 2011, and has recently been updated for accuracy and relevance.