The discovery of stem cells formed from adult bone marrow was lauded Thursday by those opposing embryonic stem cell research, but the University of Minnesota researcher responsible said both areas of research should proceed.
Embryonic stem-cell research, which is considered one of the most promising areas in medicine, hopes to grow muscle, cartilage, bone, liver, or different types of neurons and brain cells to repair organs or treat diseases such as Parkinson's. But use of embryonic stem cells has been shackled by ethical considerations because human embryos are destroyed.
"While we are excited about the potential of adult bone marrow stem cells to differentiate as we have seen in embryonal stem cells, we reaffirm our support of embryo stem cell research," Catherine Verfaillie, professor of medicine and director of the University of Minnesota Stem Cell Institute in Minneapolis, told United Press International.
"It is far too early to make a conclusion about the therapeutic potential of either adult or embryo stem cells and therefore research on both should be pursued."
If the findings are confirmed, stem cells from a person's own body could be used and turned into perfectly matched replacement tissues and even organs.
"Potentially this makes a huge difference in using adult stem cells for potential treatments and cures," C. Ben Mitchell, senior fellow at the Center for Bioethics and Human Dignity in Deerfield, Ill., told UPI. "It's a great development and a win-win for everyone and something everyone can get behind."
Earlier research on adult stem cells was believed to be less flexible and restricted to a handful of cells while embryonic stem cells were considered able to transform themselves to any tissue in the body.
Verfaillie has been able to isolate and ex vivo culture an adult stem cell population that can be expanded for more than 50 populations without obvious signs of differentiation or aging. So far, the cells have grown indefinitely, and in some cases they have shown no sign of dying after two years.
"It is possible that while embryonic stem cells may have an even greater proliferation potential and live longer, adult stem cells come from the bone marrow of healthy donors irrespective of age and even allow for treatments such as gene therapy," said Verfaillie. "Because adult stem cells can be selected and expanded under conditions that should be readily adaptable to production they may be an ideal source of cells for therapy of a wide variety of diseases."
The use of adult stem cells from bone marrow also impacts the debate over human cloning.
"This development has a tremendous impact on the resistance to banning human cloning," Wesley Smith, M.D., author of "Culture of Death: The Assault on Medical Ethics in America," told UPI. "A patient can develop an immune reaction to embryonic stem cells, so human cloning was being advocated as a way to deal with that, but since the adult stem cells come from a person's own bone marrow there is no auto-immune response and no there's no need for human cloning."
"Another drawback to embryonic stem cells was that they were believed to cause cancer tumors because their growth could not be controlled," Smith added.
Verfaillie calls the cells MAPCs, for multipotent adult progenitor cells, and they can be derived from the bone marrow of mice, rats and humans.
Unwanted cells are removed from the culture dish and the remaining MAPC cells are encouraged to grow. According to Verfaillie, her lab has isolated MAPCs from about 70 percent of the almost 100 human volunteers who have donated marrow samples.
Verfaillie's research has been published in the journal Blood, and she has a patent application pending on the process.
Last August, President George W. Bush decided to allow federally funded research with human embryonic stem cells to continue with established stem cell lines so that no new embryos would be destroyed.
"The University of Minnesota's Stem Cell Institute intends to actively pursue federal dollars to study embryo stem cells as well as work in collaboration with other labs
to pursue this line of research," Verfaillie added.
(Reporting by Alex Cukan in Albany, N.Y.)