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Now how did you copy that?  I have been trying to since last night. Nita

Hans van der Genugten wrote:

> Stem Cells Frustrate Scientists, Politicians
>
> By Rick Weiss
> Washington Post Staff Writer
> Saturday, October 9, 1999; Page A1
>
> It has been a year since researchers announced they had discovered in human
> embryos and fetuses a unique type of cell with the potential to treat a host
> of ailments, including diabetes, Parkinson's disease and even paralysis
> caused by spinal cord injury.
>
> Now, in the final weeks of bargaining over a new federal budget, a divided
> Congress is struggling to decide whether the medical promise of these "human
> embryonic stem cells" is great enough to justify the use of taxpayer money
> to study them, despite the fact that embryos and fetuses must be destroyed
> to get them.
>
> Congress has blocked federal funding of human embryo research for the past
> four years, but the discovery of stem cells has upped the ante in the embryo
> research debate. The research ban, which is attached to the appropriations
> bill for the departments of Labor and Health and Human Services, underwent
> several radical changes while the Senate addressed the bill last week, at
> various times containing prohibitions far stronger or weaker than in
> previous years. On Monday, the House will begin action on the issue.
>
> For many lawmakers, it is largely a question of whom they least wish to
> alienate: highly motivated and perhaps overly optimistic members of patient
> groups who believe that stem cells may soon save their lives or the lives of
> their loved ones, or equally passionate antiabortion activists who believe
> it is unethical to experiment on embryonic and fetal tissues.
>
> But for the many publicly funded scientists who want to investigate the
> cells, the issue is a no-brainer: The nation ought to enlist their help,
> they say, because it is becoming increasingly clear that it will not be easy
> to turn stem cells into cures.
>
> Among the more frustrating problems is how to get the cells to grow into the
> specific kinds of cells needed by patients, such as heart cells to be given
> to a heart attack victim or pancreas cells to be given to a diabetic. Today
> the cells behave as though they have a mind of their own, becoming whatever
> kind of cell they choose, and for no apparent reason.
>
> "You smile at them and they become heart, you frown and they become brain,"
> complained Tom Okarma, president and chief executive officer of Geron Corp.
> of Menlo Park, Calif., which has funded most of the human embryonic
> stem-cell work in this country. The challenges ahead, he said, "are
> formidable."
>
> Indeed, while Okarma and others still hold high hopes that stem cells will
> lead to medical breakthroughs, ongoing studies by privately funded
> scientists at Geron and elsewhere have lent an air of sobriety to a field
> that a year ago seemed almost drunk with promise.
>
> For example, it is still difficult to keep stem cells alive in the
> laboratory, and it has been impossible to grow them in numbers large enough
> to be medically useful. Moreover, scientists still don't know how to
> engineer the cells so they won't be rejected by patients.
>
> "The only way we're going to figure all this out is to roll up our sleeves
> and do the nitty-gritty research," said Harvard University cell biologist
> Evan Snyder. "There's such a clamor in the stem-cell field, but we should
> not let the clamor or the substantial promise seduce us into thinking we can
> do this quickly."
>
> Embryonic stem cells are the basic, "plain vanilla" cells present at the
> core of newly developing animals. During prenatal development, they
> differentiate into more specialized cells, such as those that form the skin,
> liver, kidneys and brain.
>
> What makes them unique is their ability to multiply indefinitely in
> laboratory dishes, where they can give rise to offspring cells that also
> have the ability either to blandly reproduce or, under the right influence,
> specialize into any of the body's tissue types. Doctors hope they will be
> able to grow a smorgasbord of replacement tissues from stem cells, for
> transplantation into people who need them.
>
> After years of funding from Geron, two research teams announced
> simultaneously last fall that they had finally isolated human embryonic stem
> cells. One team retrieved them from young human embryos and the other from
> the immature sex organs of aborted fetuses.
>
> The best news so far is that the cells seem to be as immortal as advertised,
> said James Thomson, the University of Wisconsin researcher who isolated
> human stem cells from leftover fertility clinic embryos. After almost two
> years of living and dividing in laboratory dishes, every new generation of
> cells seems just as young and full of potential as the previous one.
>
> To prove that, Thomson has injected into mice freshly grown human stem cells
> that are more than 300 generations removed from the parent cells he isolated
> from his original human embryo. Stem cells that have retained their full
> potential should, when they are injected into mice, differentiate into all
> the many kinds of tissues that they can become. And these 300th-generation
> cells have done so with exquisite creativity, Thomson said, with some of
> them becoming hair, others teeth, and still others little masses of cardiac
> cells that soon begin to beat in unison like a miniature heart.
>
> In fact, it is not difficult to get stem cells to differentiate into various
> tissues. The hard part is growing them into the specific kind of tissue you
> want – and keeping them from specializing until you are ready. Scientists
> will have to grow huge vats of stem cells in their undifferentiated state if
> they are ever to commercialize them. Currently, however, the only way to
> keep the cells in this "primordial" state is to grow them in small dishes
> along with a special type of mouse cell.
>
> The mouse cells – known as "feeder cells" – somehow keep human stem cells
> from spontaneously following their urge to specialize. But despite valiant
> efforts, Thomson and others have failed to identify how the feeder cells do
> that. It is a bottleneck scientists will need to get through if the research
> is ever going to become useful for patients, because the mouse-cell system
> is too cumbersome to scale up to commercial levels.
>
> It's not an impossible task. Several years ago, researchers working with
> mouse embryonic stem cells were in the same bind: Those cells only retained
> their full potential when grown with finicky feeder cells. Then researchers
> found that a compound secreted by the feeder cells, called leukocyte
> inhibitory factor, or LIF, was the magic substance that was keeping the stem
> cells vital. Since then, scientists have just had to add some LIF to their
> dishes of stem cells, eliminating the need for feeder cells.
>
> "After that, the mouse studies took off," recalled Roger Pederson, a
> Geron-supported researcher of human stem cells at the University of
> California at San Francisco. Unfortunately, LIF does not do for human stem
> cells what it does for mouse stem cells, Pederson said. "Someone has to
> discover the LIF counterpart for human stem cells."
>
> Perhaps even more daunting is the task of learning how to prod batches of
> stem cells to mature into specific kinds of cells for transplantation into
> people, such as liver cells for patients with cirrhosis or specific kinds of
> brain cells for patients with Alzheimer's or Parkinson's disease.
>
> Scientists have had some small successes in encouraging stem cells to turn
> into desired types, such as blood cells and nerve cells.
>
> Last December, for example, Johns Hopkins University researcher John
> Gearhart stood before a Senate subcommittee and unveiled a poster-size
> photograph of spidery living cells with branched, outreaching arms. These
> appear to be healthy human brain cells, said Gearhart, grown in a laboratory
> dish from a starter batch of stem cells by feeding them a special recipe of
> nutrients. He plans to inject some into the brains of rodents this fall, to
> start assessing their potential as a treatment for brain diseases.
>
> But Gearhart's method is far from foolproof. Many stem cells treated with
> the same nutrients do not become neurons, and retain the potential to become
> bone, muscle or other cells later on – cells that would not be welcome in a
> patient's brain.
>
> Even less is known about how to spur stem cells to grow with assuredness
> into other kinds of cells, such as the insulin-secreting pancreas cells
> that, given the prevalence of diabetes in this country, are foreseen by
> Geron as the first "blockbuster" moneymakers. Somehow, researchers will have
> to overcome stem cells' apparently fickle nature.
>
> Finally, there is the problem of immune-system rejection. Researchers want
> to figure out which molecules on stem cells are recognized as foreign by a
> patient's immune system. In theory, researchers could genetically engineer
> the cells to lack those molecules – a simple-sounding strategy that
> scientists concede will probably take many years to implement.
>
> Depending on who is talking, problems such as these add up to an argument
> either for, or against, a quick infusion of federal funds.
>
> To some on Capitol Hill, including Sen. Arlen Specter (R-Pa.), the many
> difficulties scientists face suggest that federal funds are needed if cures
> are to be developed within the next decade. Federal funding also would
> ensure a level of public oversight not possible when research is left to
> private concerns.
>
> But others, including Rep. Jay Dickey (R-Ark.), say that given the vast
> number of unanswered questions in the field, the government could satisfy
> itself by funding basic studies on animals and less controversial human
> cells, without venturing into the ethical minefield of embryo research.
>
> Further complicating the political problem, preliminary evidence from mice
> suggests that stem cells retrieved from embryos may have medical advantages
> over those isolated from aborted fetuses. That revelation, described in the
> Oct. 1 issue of the journal Science, is problematic for legislators such as
> Dickey. Last week, he sought to reword the ban in a way that would have
> precluded research on embryo cells while allowing studies on aborted
> fetuses. Fetal research is less controversial than embryo research, because
> the former can be done on fetuses already aborted but the latter involves
> the direct destruction of embryos. Dickey later withdrew the proposal.
>
> In the end, Congress may manage to duck the issue. During the past few
> months, the National Institutes of Health has created a set of guidelines
> and ethical standards that publicly funded scientists wishing to study human
> embryonic stem cells would have to follow.
>
> The guidelines would preclude researchers from retrieving stem cells from
> embryos directly, because that act causes the destruction of live embryos.
> But researchers would be allowed to study stem cells from embryos that
> someone else had destroyed or from aborted human fetuses.
>
> Many in Congress see the guidelines as a good compromise – and as a way to
> eliminate at least one controversial element from a bill that is already
> making waves with provisions relating to abortion and birth control. On
> Thursday, the Senate passed its version of the HHS bill with no restrictions
> on stem-cell research.
>
> On Monday, the House will take up its version of the bill. And if
> representatives decide they can live with the NIH guidelines – a far from
> foregone conclusion – they too may drop the ban.
>
> But the suspense might not end there. Many Congress-watchers predict that
> the House and Senate versions will defy congressional consensus on other
> counts, and ultimately will get folded into a huge omnibus spending bill.
>
> Omnibus spending bills are negotiated outside the usual committee circles
> and are famed for ending up with unexpected changes – the result of
> horse-trading efforts in the wee hours of an already extended budget
> process. That means that, for all the lobbying on both sides of the issue,
> the legislative resolution to this year's biggest biomedical controversy may
> not become clear until the dust settles at the end of a frantic, closed-door
> session.
>
> © 1999 The Washington Post Company