On the same day that Health Journalism 2009 featured a panel on "Second wind for stem cell research," The National Institutes of Health issued draft guidelines to allow government funding for stem cell research.
The guidelines would restrict such research to cells derived from discarded embryos at in vitro clinics. The contribution of the cells would be voluntary, with no financial incentive to couples who donate, and with no direct medical benefit.
The ruling does not provide funding for human embryonic stem cells (hESCs) derived from other sources, such as nuclear transfer, parthanogenesis, or IVF embryos expressly made for research. Chuck Murry, M.D., Ph.D., co-director of the University of Washington's Institute for Stem Cell and Regenerative Medicine, noted that the United Kingdom allows the use of IVF embryos make for research.
A 2001 executive order from President Bush had forbid federal funding of research with embryonic stem cells.
"The Bush ruling had cast a pall, a moral cloud, over stem cell research and a lot of good scientists and young people didn't get into this field. We lost some people to the UK," Murry said.
Lawrence Goldstein, Ph.D., a stem cell researcher with the University of California San Diego and a member of the board of the International Society for Stem Cell Research, explained that "One of the problems was that young people who we wanted to come here to study, left after their degrees to return home. The previous ruling was hurting the next generation of stem cell scientists. Now, in California, there's evidence about a change in this climate. With California's stem cell initiative and funding, people are moving here (to CA) be be part of this research effort."
Goldstein and Murry commented on the NIH announcement that follows President's Obama's March 19 executive order overturning President Bush's 2001 order to forbid federal funding of research with embryonic stem cells.
Goldstein explained three different sources of stem cells:
- adult stem cells (tissue, fetal, cord, amniotic, etc) These are restricted in their ability to make all types of cells
- embryonic stem cells – the controversial ones that come from the blastocyst stage, and are pluripotent, meaning they can become many but not all types of cells
- reprogrammed stem cells. This is the newest, latest…an example would be skin tissue taken then turned, by the scientist, back into a blastocyst cell, thus ending up with a pluripotent stem cell that shares the same properties as an embryonic stem cell.
The problem with reprogrammed stem cells is that "we still don't know if it will work. There are many unknown scientific problems. And, the current methods are probably not safe for transplantation," Goldstein said.
So, how can we accelerate stem cell research, now that federal funding will be restored?
Goldstein said there are three issues:
- A large amount of time is spent treating diseases and we don't really understand many of these diseases. For example, in diabetes we need to damp down the immune system as well as deal with beta cells, and in ALS the neurons die but we've learned it may be possible to transplant in other cells from the "neighborhood" next to the defective cells.
- We need to find ways to make clinical trials safer. After cells are transplanted, do they stay where they are put? What if the transplanted cells do something bad? LG gave examples of Parkinson's case where transplanted fetal cells caused patient to get worse, and a "bubble boy" case in France where the child got tumors after stem cell transplantation.
- Accurate communication is needed about results of clinical trials, especially since there are now overseas clinics that claim success with stem cells and some people travel for these unproven therapies. Additionally, the media needs to be very careful in reporting the results of early trials, such as Phase I safety trials, so that public isn't misled to believe there's a cure.
Murry further discussed the NIH ruling and called it a "use but don't make" policy.
He said in his lab, they tried for five years to make new heart cells with adult stem cells and it didn't work. When they tried embryonic stem cells, it was successful.
"In heart failure, you can manage the symptoms, but not the cause of the disease," he said. "There is no robust repair that takes place in the heart. So this is what we're trying to do with stem cells."
One of the biggest challenges is to control differentiation. Human cardiac muscle cells will beat indefinitely in a petri dish, but they don't know yet what to do with them. They tried transplanting them, but the cells died "because they didn't get any blood flow," he said. Now his lab is trying to put together a human blood vessel network.
Murry said a possible future application with stem cells will be patient-specific stem cells, where the patient's own adult cell will be reprogrammed for a new use. This prevents the need for immunosuppressive drugs.
Goldstein and Murry said they believe the big breakthrough in stem cell research will be with the reprogrammed cells. For example, start with a simple adult cell, such as a skin cell, and reprogram it back to a pluripotent cell. This eliminates the moral concerns, Murry noted.
Both researchers said they and others wouldn't be at this point without their experience with actual embryonic stem cells, however. "We never would have gotten here without learning with human embryonic stem cells," Goldstein said.
He provided an analogy for using reprogrammed adult cells. If you have a teaspoon of sugar, it tastes sweet. But, if you heat the sugar, it tastes bitter. You have manipulated it to become bitter tasting.
Asked what the Obama executive order's influence will be on stem cell research, Goldstein said it will increase the speed and efficiency of research.
"But we need to remember that problems are really hard to solve and it will take a lot of work," he said. "The answers won't be tomorrow. But it may be in eight years, instead of 12 if the Bush policy had continued."
