WASHINGTON, Aug. 23 (UPI) -- Advanced Cell Technology said Wednesday its researchers have developed a technique to harvest human embryonic stem cells without harming embryos, an advance that could remove ethical objections to the research.
However, it remains unclear if the Bush administration will be persuaded by the new technique and ease restrictions on federal funding of the controversial research, which could lead to insights and even treatments for various disorders and diseases.
The study, which appears in the online version of Nature, involves a technique called preimplantation genetic diagnosis that is routinely used at fertilization clinics to screen for genetic disorders. This involves extracting or biopsying cells from an early-stage embryo (a blastomere), after which the embryo can then be implanted in the womb where it develops normally, apparently unharmed.
Robert Lanza, Advanced Cell's vice president of research and scientific development, and colleagues modified the technique slightly to use one of the biopsied cells to generate an embryonic stem cell line.
"We've shown it is now possible to obtain stem cells without harming the embryo," Lanza told United Press International.
In the study, Lanza's team used the biopsy technique to generate two stable human embryonic stem cell lines from 16 blastomeres. The resulting stem cell lines appeared equivalent to lines developed using conventional techniques, including being genetically normal and having the potential to develop into all cell types of the body.
The technique "removes the most basic objections to embryonic stem cell research," Lanza said, adding that he thinks it could solve the current political impasse on easing the limits on federal funding.
"We're hoping the method can be used to increase number of stem cell lines available for federal funding and give the field a jump start," he said. This could be particularly important for generating lines that have not been exposed to animal feeder cells, a potential dilemma for the stem cell lines currently approved for federal funding.
However, it remains to be determined whether the Bush administration will see things the same way. Congress passed a bill this summer that would have allowed federal funds to be used for research involving embryos from fertilization clinics that were destined to be discarded, but president Bush vetoed the bill last month in the first use of his veto power in his presidential tenure.
James Battey, chair of the National Institutes of Health's stem cell task force, told UPI the legal language pertaining to this issue from both Congress and the president contains enough ambiguity that it is up in the air whether this technique would qualify for federal funding.
"We could certainly need guidance from the executive branch," said Battey, who also serves as director of the National Institute of Deafness and Other Communicative Disorders. "These days in biomedical research having a law degree is every bit as important as having a medical degree."
The Dickey Amendment, which pertains to how NIH funding can be used for stem cell research, stipulates that no monies can be doled out by the agency for research in which a human embryo is destroyed or subjected to a risk of injury or death.
Battey said that everything we know about the preimplantation genetic diagnostic technique appears to indicate it is safe for the embryo, but there could still be a chance that it could or does cause damage.
Bush limited federal funding of the research to stem cell lines derived prior to Aug. 9, 2001, which would on its face appear to indicate that stem cells derived using Advanced Cell's technique would not qualify for funding, Battey said.
However, he noted, even this becomes unclear because Bush was referring to an older technique that involved the destruction of an embryo, not Advanced Cell's technique that doesn't require destroying the embryo and may pose no harm.
Another question, Battey said, is whether the blastomere has the same moral and legal status of an embryo because the jury is still out on whether it could give rise to a full individual.
However, Lanza said his technique involves extracting the cells at the 8-cell stage and by this point the cells do not have the potential to go on to develop into a complete person.
"No one has ever shown that a single blastomere at the 8 cell stage has been shown to generate a complete organism in any mammalian species, including a mouse or rat," he said.
