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Tuesday, January 24, 2012 - Page updated at 08:00 p.m.
Embryonic stem cells restores some sight
By Rob Stein and David Brown
The Washington Post
For the first time, an experimental treatment made from human embryonic stem cells has shown evidence of helping someone, partially restoring sight to two people suffering from slowly progressing forms of blindness.
Although the experiment's purpose was to test the safety of stem cells injected into the eye, both patients "had measurable improvement in their vision that persisted through the duration of the study," said Robert Lanza, chief scientific officer at Advanced Cell Technology, the Massachusetts biotech company that sponsored the closely watched experiment.
The operations in July on two Southern California women yielded practical results. One of them no longer needs a large magnifying glass to read and can reportedly thread a needle. The other has begun to go shopping on her own.
Reported online Monday in the Lancet, the project used the cells under highly favorable conditions not likely to exist with many other diseases.
The cells were transplanted into the eye, an organ in which the chance of immune rejection is low.
Lanza cautioned that the findings are preliminary, the improvements could disappear and complications could emerge. Nevertheless, he thinks the two cases will provide useful lessons.
Embryonic stem cells are able to develop into virtually any type of tissue in the body, but to obtain them, embryos are manipulated and sometimes destroyed.
Many researchers hope the cells — or other "pluripotent" cells derived from less controversial sources — will offer cures for heart disease, cancer, Alzheimer's disease, dementia, spinal-cord injury and other ailments.
Until now, the strategy had shown promise only in laboratory studies and animal tests. After many delays, the Food and Drug Administration last year approved two experiments in people. The blindness trial is the first to publish evidence that the approach might be working.
In October 2010, doctors in Atlanta injected millions of cells into the spine of a 21-year-old Alabama nursing student partially paralyzed by a car accident. Subsequently, four other similar patients were treated. The only results released about those patients is that none has suffered any harm.
But Geron, which was sponsoring the study, recently announced that money problems had forced it to abandon plans to treat more patients, stunning researchers, advocates and patients.
One patient in the new study is a 51-year-old graphics artist from Los Angeles, and the other is a 78-year-old woman from Laguna Beach, Calif. Both had some vision but were legally blind.
In interviews with The Washington Post weeks before the results were made public, both patients said they were thrilled.
Within about six weeks of having the cells infused into her eye, the Los Angeles graphic artist noticed something.
"I just woke up one morning and looked through one eye and the other, and the difference was pretty dramatic," she said. Since then, her vision has improved, enabling her to read more characters on an eye chart, thread a needle and see colors, she said.
Her sight had started fading when she was in her 20s because of Stargardt's macular dystrophy, a progressive form of blindness that often begins in childhood. Since the July 12 procedure, she's regained enough vision to start biking again.
Tests indicate that healthy cells have grown where the treatment was injected, increasing confidence that the cells are responsible for her better sight.
The second patient, Sue Freeman, had been slowly losing her vision for more than 20 years because of dry macular degeneration, the leading cause of blindness in the developed world. Freeman had been forced to stop driving. But within about six weeks of the procedure, Freeman started noticing changes.
"I started telling my husband, 'You know, things seem brighter to me.' I don't know if it's my imagination, but looking at landscapes seemed brighter," she said, noting that she persuaded her husband to drop her off at a mall by herself for the first time in years.
Psilocybin, the active ingredient in so-called magic mushrooms, may help people with depression, based on two studies that suggest the drug could have a lasting effect on patients. In a study published Monday in the Proceedings of the National Academy of Sciences, 30 healthy volunteers took psilocybin intravenously and had their brains observed with MRI scanners. Activity in the medial prefrontal cortex, which is hyperactive in depression, was consistently lowered, according to the study led by David Nutt and Robin Carhart-Harris of Imperial College London.
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