Therapeutic Medicine: Stem Cell Treatments to Restore Eyesight
4 Min. Read | August 26, 2021
How Can Stem Cells Repair Vision Loss?
Age-related Macular Degeneration—the leading cause of vision loss in adults in the U.S.—is also a lead candidate in the race to use stem cells to repair us. Stem cell treatments don’t directly replace the rods and cones in the back of the eye that allow us to see. Instead, in the lab stem cells are grown into sheets of support cells called retinal pigment epithelium (RPE). When those sheets of cells are carefully placed at the back of the eye, they have been shown to improve vision.
Six of the eight organizations (below) with trials underway or in the late planning phases are using a type of stem cell called an induced Pluripotent Stem Cell (iPSC). Lineage and Patch use a different type of pluripotent stem cells to make the needed RPE layer.
The First Clinical Trial in the United States
The National Institutes of Health began the first clinical trial in the U.S. using iPSCs for therapy in December 2019. Kapil Bharti leads that trial in patients with a type of AMD called geographic atrophy. He explained how they have refined their process in a recent webinar hosted by the publication EndPoints. They are making personalized cells starting with iPSCs made from the patients’ blood cells. They had tried using skin cells, like is often used in research, but they found blood cells produces stem cells that were much more genetically stable. They also found that cells from younger patients were more stable than those from older patients.
Both those findings reinforce the value of blood cells stored in the GoodCell personal biobank. One type of cell stored has been shown to be very efficient at making iPSCs. And stored cells are the youngest and healthiest available to patients when they need them.
Early Trials Show Improved Vision
Lineage and Patch began their clinical trials some years earlier using donor embryonic stem cells, but those trials using cells not immunologically matched to the patient require some immune suppression. Using cells from personalized iPSCs does not.
Patch announced results in June for the first 15 patients with late-stage disease. A third of the patients showed improved vision and another third showed no decline in vision, in a disease that is almost always rapidly progressive. In the trial, only one eye is treated and the untreated eye did have worsening vision in 80 percent of patients.
Also in June, Lineage reported more results from its 12 patient trial. They found 83 percent had vision at or above baseline in the treated eye and the same percent reported worsening in the untreated eye.
Earliest Trials in Japan
Japan’s Shinya Yamanaka, won the Nobel Prize for discovering how to make iPSCs in 2012. Ever since the country has put a great deal of resources into developing IPSC-derived therapies and streamlined the process of getting the therapies into clinical trials.
Riken injected the first personalized RPE cells into a patient in 2014. They reported that the progression of degeneration of the retina in the eye halted, some photo receptors recovered, and the patient’s vision remained stable. Other similar trials are underway in Japan at this time.
The Future for Stem Cells in Vision Research
Trials using RPE shore up the health of any remaining photo receptors, but don’t replace them. A team at the University of London reported in May that they had found a way to make photo receptor cones directly from iPSCs in mice.
Many researchers around the world are using iPSCs to develop mini-organs, or organoids, in the lab to study diseases and develop therapies. Believe it or not, one of the most common is brain organoids. No, they can’t think. But they can be used to study nerve communications, both normal and in disease states.
These brain organoids are becoming increasingly complex, and just this month a team at University Hospital Dusseldorf, Germany, created brain organoid with two early structures of eye formation, the optic cup. The senior author of the study said the group wants to use the model to study eye-brain interactions, and eventually develop patient-specific cells to test personalized drug therapies and possibly cell transplantation.
The teams using iPSCs to restore vision are just the tip of the iceberg of trials using iPSCs. The value of the iPSC progenitor cells stored by GoodCell is manifested in the dozens of clinical trials for other diseases that are underway or in the late stages of planning around the world.
Who is Testing Stem Cells in Vision Loss Due to Age-related Macular Degeneration (AMD)?
- National Institutes of Health
- Regenerative Patch Technologies
- BlueRock Therapeutics
- Healios K.K.
- Hopstem Biotechnology
- Osaka University
- RIKEN Research Institute
- Lineage Cell Therapeutics