Color-enhanced image of retinal pigment epithelial cells derived from human embryonic stem cells.
Researchers in January released the results of a groundbreaking study that showed human embryonic stem cells can safely help reverse eye disease. The study, conducted at the Jules Stein Eye Institute at the University of California, Los Angeles (UCLA), used retinal cells created from embryonic stem cells supplied by a biotechnology company. The retinal cells were injected into the eyes of two patients suffering from two different forms of progressive blindness and, in time, significantly improved their vision.
The safety study not only showed that cells derived from embryonic stem cells can be safe for patients, it also demonstrated their life-changing potential. The success of the experiments is a major milestone for the controversial and often-restricted field of human embryonic stem cell-based therapy. The study’s promising results warrant new investments and heightened interest in stem cell research.
The clinical trial at UCLA was designed to solely test the safety of a stem cell-based therapy — not its effectiveness. There are many potential risks involved with stem cells. The body could reject the new cells, or the cells could cluster together to form tumors or migrate to other regions of the body. The eye was chosen for the study because it is uniquely isolated from the rest of the body, limiting potential damage should one of those risks come into play. However, neither patient in the study showed any negative effects after the retinal cell implant. Additionally, both experienced significantly improved vision, which was not the intent of the trial.
The first patient to receive the retinal cells was 78-year-old Sue Freeman, who was diagnosed in 1998 with age-related macular degeneration and eventually lost the ability to do daily tasks like reading or shopping. As a result of the experimental stem cell therapy, she is now able to read seven progressively smaller letters on a standard eye chart. The second patient went from seeing only hand gestures to distinguishing the movement of individual fingers.
The exciting potential of stem cell therapy is not limited to restoring sight to the blind. Since stem cells can become any type of cell within the body, researchers hope they can one day help cure a wide range of diseases and restore damaged cells throughout the body. The news of a safe and successful clinical trial is welcome in a field of study marked by legal restrictions and very limited research funds. Legal cases restricting research have been upheld and overturned multiple times, and previous studies have been terminated prematurely due to a lack of funds. Political and legal roadblocks hinder the development of life changing therapies such as retinal cell implantation. Restrictions should be removed and funding increased to encourage research that continues to develop stem cell therapies.
In the past, decisions regarding embryonic stem cell research were necessarily based on the potential benefits of cell-based therapies. The UCLA study is preliminary evidence that the benefits are indeed real, and that we have only begun to tap the amazing potential of human embryonic stem cells.
H. Scott Horton is a second year graduate student at Rice University on the Professional Science Master’s Program nanoscale physics track. He is a student in the class “Science Policy and Ethics,” taught by Kirstin Matthews, Baker Institute fellow in science and technology policy.