"It's good that the study is focusing attention on another cell type that should be considered along with other cell types," said Helen Blau, director of the Baxter Laboratory in Genetic Pharmacology at Stanford University. But she added, "They do not constitute a substitute for embryonic stem cells at this time. Much more research would be required to determine that."
At the time a baby is born, doctors can harvest the blood from the umbilical cord. Frozen and stored, the umbilical cord blood is a rich source of stem cells which can be used to treat as many as 70 different diseases.
Clinical applications thus far have shown that the cells harvested from cord blood do, indeed, have treatment potential. So far, about 6,000 Americans have received cord blood transplants. Most commonly, the cells are used to regenerate the immune systems of patients who have received treatment for leukemia. And some researchers suggest that as the field of applications broadens, this number could grow.
"Since umbilical cord blood, an adult-derived stem cell source, contains multipotential stem cells with functions similar to cells derived from embryonic stem cells, I do not anticipate that if the embryonic stem cell bill is not passed, that this will significantly impede our progress in stem cell therapeutics in human clinical trials," said Dr. Mary Laughlin of Case Western Reserve University.
As with most of the other alternatives, researchers do not believe that cord blood cells hold the same promise as embryonic stem cells.
"There may be technology developed in the future that allow patients and parents to find it useful in a clinical setting, but there is a lot of science needing to be performed before any of this stem cell hype becomes reality," said Bryon Petersen, associate professor of pathology at the University of Florida.
In this procedure, doctors remove a single cell from an embryo very early in its development. By doing so, they can obtain a relatively undifferentiated cell, ostensibly without harm to the developing fetus.
Proponents of the technique say it offers access to a cell that, while not quite as biologically "flexible" as an embryonic stem cell, still has the potential to transform into a wide variety of cells and tissues.
"For the first time we are able to create life without destroying it," said Dr. Robert Lanza, following the publication of his August 2006 article on the technique published in the journal Nature.
Lanza, vice president of Research and Scientific Development for the Massachusetts-based Advanced Cell Technology, said at the time that he believed the technology would eliminate the current governmental restrictions on stem cell research.
While the technique is designed to preserve the developing embryo, some researchers note that there is still some risk involved.
"The long-term consequences to the child are completely unknown," said Dr. William Hurlbut, consulting professor at the Neuroscience Institute at Stanford University Medical Center. "Something subtle but significant might be changed in the final physical frame or personality of the person born -- like tipping the rocket slightly on the launch pad, a tiny tilt might make some difference in the final destination.
"From a practical perspective I think this may cause some political stir, but I don't think it will be greeted as much of a solution."