Stem cell hope for leading cause of blindness.
A preliminary report for a study using human embryonic stem cell transplantation into the eye has sparked hope for reversing the devastating effects of macular degeneration. It’s also the first time ‘human’ embryonic stem cells have ever been used.
Above: How the world can look for someobody with macular degeneration
By Keryn Curtis
A world first experiment using human embryonic stem cells has shown a measurable improvement in the sight of two women with macular degeneration.
The findings come from a preliminary report published yesterday in the prestigious British medical journal, The Lancet, concerning a study by researchers from the University of California (UCLA) and biotechnology company, Advanced Cell Technology (ACT), which also funded the work. In the study, researchers sought to establish the safety and tolerability of transplanting human embryonic stem cells (hESC) into the eyes of patients with two forms of macular degeneration.
The two patients were women who were ‘legally blind’ at the time of injection of the human embryonic stem cells. One woman in her 50s has Stargardt’s macular dystrophy while the other, in her 70s, has dry age-related macular degeneration – the leading cause of blindness in the developed world.
Reporting the findings, the authors say, “structural evidence confirmed cells had attached and continued to persist during our study”. Both women showed positive results – increasing their ability to identify letters on a sight test chart – with no signs of rejection or any abnormal signs during the first four months.
While the authors admit there is ‘little agreement’ between investigators on visual endpoints or outcomes in treating patients with low vision, they were encouraged that neither patient lost vision during the observation period.
They believe the future goal will be to treat patients earlier in the disease process, potentially increasing the likelihood of visual improvement.
The study has attracted wide media interest around the world, partly because of the hope it offers to the hundreds of thousands of people around the world who have macular degeneration, but also because, while human embryonic stem cells were first discovered 13 years ago, this is the first time that they have been transplanted into human patients for any purpose.
Above: Dr Robert Lanza, Chief Scientific Officer, Advanced Cell Technology
In a press release from Advanced Cell Technology, co-author and chief scientific officer of ACT, Dr Robert Lanza, said if the treatment was proven to be safe and effective in more patients over time, the stem cells could be used early in the disease process to improve the prospects of people retaining their sight.
”This is the first report of hESC-derived cells ever transplanted into patients, and the safety and engraftment data to date looks very encouraging.
“Stem cells provide the possibility of providing new treatment strategies for currently incurable retinal degenerative diseases. Although these initial studies are designed to determine the safety and tolerability [of hESC-derived RPE], we eventually hope to treat patients earlier in the course of the disease, further increasing the likelihood the new cells will rescue photoreceptors and prevent visual loss. We recently initiated two clinical trials in the U.S. and are very pleased to be starting the first clinical trial in Europe.”
For information about macular degeneration, go to the Macular Degeneration Foundation of Australia website or call the support line on: 1800 111 709
