ON THE CUTTING EDGE: No Embryos Were Harmed In The Making Of These Organs
Yale University researchers built partly functioning lungs from cells taken from the lungs of rats and then transplanted the organs into live rats. “[T]he new organs successfully exchanged oxygen and carbon dioxide, just as natural lungs do,” reports The Wall Street Journal:
The study, funded by Yale and the National Institutes of Health, builds on a handful of similar groundbreaking experiments of recent years. A breakthrough using the same technique occurred in 2008, when University of Minnesota researchers created a beating rat heart in the lab. In a June 13 paper in Nature Medicine, scientists from Massachusetts General Hospital and elsewhere described how they had used the method to create a rat liver.
"It's an approach that has repeatedly been shown to have promise," said Anthony Atala, an expert in regenerative medicine at Wake Forest University Baptist Medical Center, who wasn't involved in the latest study. Dr. Atala cautioned, however, that it could be years or even decades before such experiments could be tried in people.
Regenerative medicine is a hot field. Lab scientists are trying to regenerate everything from simpler body parts - skin or arteries - to more complex organs, such as the uterus. In 2006, Dr. Atala and his colleagues described how they used a patient's tissue to create the first lab-made bladder. More challenging yet is the effort to remake solid organs, such as the liver and lung.
Meanwhile, Italian ophthalmologists have restored the sight of dozens of people who had been splashed with caustic chemicals using transplants of their own stem cells, reports The Associated Press:
The treatment worked completely in 82 of 107 eyes and partially in 14 others, with benefits lasting up to a decade so far. One man whose eyes were severely damaged more than 60 years ago now has near-normal vision. …
The approach would not help people with damage to the optic nerve or macular degeneration, which involves the retina. Nor would it work in people who are completely blind in both eyes, because doctors need at least some healthy tissue that they can transplant.
In the study, published online by the New England Journal of Medicine, researchers took a small number of stem cells from a patient's healthy eye, multiplied them in the lab and placed them into the burned eye, where they were able to grow new corneal tissue to replace what had been damaged. Since the stem cells are from their own bodies, the patients do not need to take anti-rejection drugs.
Adult stem cells have been used for decades to cure blood cancers such as leukemia and diseases like sickle cell anemia. But fixing a problem like damaged eyes is a relatively new use. Researchers have been studying cell therapy for a host of other diseases, including diabetes and heart failure, with limited success.
Adult stem cells, which are found around the body, are different from embryonic stem cells, which come from human embryos and have stirred ethical concerns because removing the cells requires destroying the embryos.
The AP omits another important distinction between adult and embryonic stem cells: Adult stem cells are already being used therapeutically to repair and replace damaged organs, whereas embryonic stem cells have yet to produce any useful tissues or therapies.
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