"We don't need any eggs or embryos at all," says Shinya Yamanaka, MD, a professor at the Institute for Frontier Medical Sciences in Kyoto, Japan.
Yamanaka describes his lab's early successes in mice creating stem cells from adult cells. His research involves isolating two dozen chemicals that give embryonic stem cells their ability to grow into nearly any tissue in the body.
How long does it take for news of embryonic-like cells from the patient's own cells and from umbilical cord blood cells to make it to the mainstream media and the daily medical news pages? This article was published election day, although Dr. Yamanaka published his report months ago. Perhaps the stem cell scientists could begin to share their information more openly and much more quickly. Perhaps they could start a new tradition: prestige for rapid and frequent sharing of information that is immediately used and referenced by other scientists. Sort of like the prestige we bloggers aspire to.
The cells that Dr. Yamanaka has developed have the same properties as the cells derived from destroying embryos, they even cause tumors when emplanted in mice:
That property, called "pleuripotency," is what makes scientists think stem cells can be coaxed to form new tissues that could help cure Parkinson's and other diseases.
The Japanese researchers found that four of the chemicals, in the right mixture, transformed connective tissue cells from adult cells into pleuripotent cells Yamanaka says are "indistinguishable" from embryonic stem cells.
Still, significant problems remain.
"I have to point out, the efficiency … is very low," Yamanaka today told the scientific conference hosted by the Institute of Medicine. Only one in 1,000 attempts to transform adult cells into stem cells was successful.
Also, the cells formed tumors when implanted in mouse tissue -- a significant roadblock to using such cells for human treatments.
As a matter of fact, one of the classic tests of "stemness" is the ability of embryonic stem cells to make teratomas, a mass of several different types of cells, when injected into the body of mice. This is what other scientists look for when some lab, somewhere, reports they've derived embryonic stem cells. The next step is to induce these cells to grow "indefinitely" while maintaining this "stemness" and avoiding genetic mutations.
All embryonic stem cells are rare, efficiency is low and the property of making tumors must be overcome. This is the nature of the cells.
However, Dr Nico Forraz and Professor Colin McGuckin, working with scientists from the University of Texas Medical Branch at Galveston and NASA have been able to produce embryonic-like stem cells from umbilical cord cells, have been able to cause the cells to divide to make larger numbers of cells, and induce some of those cells to turn into functional masses of liver cells.
In addition, researchers at the University of Michigan have produced functional type II alveolar lung cells from umbilical cord blood cells. These cells make surfactant, the mixture of lipids and proteins that line the airways of the lungs and allow us to breathe by preventing the alveli (the little pockets that take in oxygen and give off carbon dioxide) from collapsing. This is one of the types of cells that give patients with cystic fibrosis trouble and study of these cells may help us learn to treat the disease.
In their rush to be the next superstar of stem cells, scientists appear inefficient and definitely disorganized to those of us who are watching from the sidelines. From UK scientists who want to make embryos using cow eggs and human nuclear DNA, to scientists who brag that they used mouse embryonic stem cells - rather than Dr. Nicco's human liver cells - to create an artificial liver.
Then, we have confirmation from Glenn McGee, over at blog.bioethics.net, of news shared here in the past that "as much as half of stem cell revenue" from embryonic stem cell scientists who honor the US patent laws will go to the Wisconsin Alumni Research Fund.
It's easy to criticize when you're not sitting at a lab bench 20 hours a day. However, that's what ethicists (and critics and bloggers, etc.) do, I'm afraid. I believe the criticism has a valid point, though: Embryonic stem cell researchers need to realize the rate of change in their field, and utilize modern methods of sharing information and awarding prestige in order to help human patients sooner and more ethically.
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