1. Human embryonic stem cells: promise, potential problems.
2. "Solving" the financial challenges facing healthcare.
3. The Republican Congress twice tried to outlaw them, entirely.
Human embryonic stem cells (hESCs) will be derived from embryos that were made for in vitro fertilization, but would otherwise be discarded, literally tossed down a drain.
Human embryonic stem cells, promise, potential problems. Yesterday, President Obama signed regulations lifting the Bush ban on federal funding of human embryonic stem cell research. These hESCs have, like an embryo, the potential to become any cell of the body--a blood cell to fight infection, a nerve cell to carry impulses to muscles, a pancreas cell to make insulin, a heart cell to repair damaged heart muscle, an eye cell to regenerate a damaged retina.
"Needle-ready". Sometime this spring or summer, a paraplegic patient destined for a life in a wheelchair will receive an injection of hESCs in the spinal cord at the area of injury. These hESCs will have been pretreated in a dish with growth factors that have "goosed" them to become nerve cells. They were then frozen and preserved in vials and can be shipped to hospitals to be stored in freezers--not dissimilar to how drugs are made, shipped and stored.
It may be that one or more of these patients will stand up from their wheelchairs 6 months after treatment. More likely, this will be just the beginning of a long process learning how to use these extraordinary cells in the treatment of a wide variety of diseases or conditions.
Rats with crush injuries to their spinal cords have been treated with these hESCs and regained the ability to walk, hold their tails off the ground, and stand on their hind legs whereas their untreated cage mates remained paralyzed.
Note, these were human cells in a rat. One might have predicted that the rats would reject them as "foreign" because they were human, but they did not. Therein lies the promise. These cells may be able to prevent their own rejection just like the embryo--half of whose genes are different from mom's--and thus may be used to treat a large number of patients because they do not need to "match" the recipient like blood cells in a bone marrow transplant (one person's bone marrow cells donated to another).
Therein also lurks a potential problem. If these cells "revert", that is, go backwards in their programming, they may grow unregulated into a tumor using that same "anti-rejection" machinery to provide a sanctuary from the body's immune system.
All these issues--dose, state of differentiation into specific cell types, rejection, reversion--will be the subject of intense research over the next decade. Now, with federal funding, that research can be kicked into high-gear. In addition, embryonic stem cell lines with genetic abnormalities associated with specific diseases will enable biologists to deepen their understanding of the diseases, and point to new strategies for therapy.
There are other approaches to regenerating human tissues from stem cells. One is to use the recipient's genes to replace the genes in the embryo, so that the cells injected are identical to the recipient's, so there is little risk of rejection. That process, however, requires an embryo for each patient.
Another approach is to isolate adult stem cells from tissues in the body and use growth factors to expand them. This, too, requires patient-by-patient preparation but uses more mature cells that may be less likely to "revert" and thus cause tumors as described above. A variant of this strategy is to take a known stem cell, such as from the bone marrow, and get it to revert to a more general stem cell in a dish, and then "goose" it along any of the cell type pathways.
Stem Cell therapies can "solve" the long-term financial crisis in medicare. While I support the President's efforts to control healthcare costs and provide universal healthcare, his action yesterday on stem cells that may provide breakthroughs in the treatments of diabetes, Alzheimer's, and other widespread chronic illnesses will have more impact on those costs than any of the other changes he proposes to enact.
Diabetes is not just a problem of too much sugar in the blood. The consequences of that abnormality is narrowing of the small blood vessels that feed oxygen to organs, and thus cause diseases of those organs as well: kidney failure, blindness (small blood vessels on the back of the eye), amputation (sores that do not heal and become infected due to lack of adequate oxygen), heart attack, and so forth.
Diabetes and its complications are projected to account for ~15-25% of the costs of medicare.
There are freezers holding hESCs that have matured along the pathway to make insulin, the hormone that controls blood sugar. Successful development of these cells in clinical trials could, therefore, resolve up to one-quarter of the projected costs of healthcare in the United States. With federal funding for stem cell research, that development process--that may take a decade--will be on the front-burners. A successful outcome not only saves children the worry and pain of multiple needle sticks per day, but also the complications, and help the healthcare system toward solvency.
Replacing brain cells damaged by accumulating a protein that leads to Alzheimer's disease and the atrophying cells in a portion of the brain that is associated with Parkinson's disease would not only ameliorate enormous suffering, but bring additional cost savings to the system
These developments will have far more impact on limiting healthcare costs than any rejiggering of the system, and will make universal healthcare access affordable for the country.
The Republican Congress tried twice to outlaw stem cells. Most people are aware of George Bush's rather schizophrenic ban on federal funding for hESC research, on the basis that it is destroying life (the embryo). The problem his followers have had in sustaining their positions is that the alternative is to flush these embryos down the toilet. In vitro fertilization clinics make more embryos than can be safely implanted (octomom comes to mind!), and parents may not wish to donate all those non-implanted embryos to others.
Unless embryo donations become mandatory, the only alternatives are to flush them down the toilet or use them in hESC research. What religious doctrine prefers toilets to laboratories and medical clinics?
Bush did not outlaw all hESC research, just federal funding for all but a select set of cell lines.
But, sub rosa, there was an even more insidious attempt to stop hESC research. The House Republicans twice outlawed all hESC research, and even had a provision to arrest people at the border if they went overseas to get hESC therapy. [The only reason this was not seriously entertained in the Senate--the filibuster. It is likely Bush would have signed it. So, before the rush to abolish the filibuster because it is inconvenient, remember how much further behind this key science would be if the DeLay Republicans had had their way].
Here is their mantra:
1. "hESCs have not cured a single patient". Well, true, but it is difficult to cure anyone when it has never been tested. Thanks to Bush and the Republicans, hESCs have not been tested in patients; moreover, medical treatments require a decade or more to develop and understand how to use them. When adult bone marrow stem cells were first tested, they didn't cure anyone either.
2. "Adult Stem cells have cured people of many diseases already". This claim refers to bone marrow transplantation that has been developed for 30 years.
Challenge anyone who uses this argument with these questions: have adult stem cells cured patients of diabetes? Alzheimer's disease? Paraplegia? Parkinson's Disease? Stroke? Heart failure? (Hint: the answer is "no"].
3. "The use of an embryo is like killing a person". Should parents who decide to discard additional embryos be tried for murder? Should IVF clinics be forbidden from freezing embryos, forcing women to endure multiple procedures if the first IVF attempt does not work? [Hint: those making such claims will avoid answering these questions].
Because of the President's actions, March 9, 2009 will be one of history's most notable days. And, another reason why November 4, 2008 was such a transformative election--and why the electoral fraud of 2000 was so devastating.