Forgot your password?
typodupeerror
Biotech Science

Grow Your Own Heart Valves 180

Posted by samzenpus
from the congen-circulatory-sphincters dept.
jcr writes "Medical researchers in Britain have succeeded in growing a heart valve from adult stem cells taken from bone marrow. The research is being reported in the journal of the Royal Society today. Growing a heart value from your own cells means that tissue rejection isn't an issue."
This discussion has been archived. No new comments can be posted.

Grow Your Own Heart Valves

Comments Filter:
  • by jimstapleton (999106) on Tuesday September 04, 2007 @10:33AM (#20463967) Journal
    Quite incorrect. The fundies only dislike fetal stem cells and full-organism cloning. This shouldn't cause an issue with them.
  • Re:Whole heart next? (Score:5, Informative)

    by jimstapleton (999106) on Tuesday September 04, 2007 @10:37AM (#20464013) Journal
    embryonic are omni-potential, instead of just pluripotential.

    Until the last two or three years (if I remember correctly, the time frame may be off), with adult stem cells, they can grow a limited set of tissues only. Even now it takes work to make adult stem cells able to differentiate into any other cells. Embryonic stemm cells however can change into anything, without any modification. They are much easier to work with, and as of a couple of years ago they were the only option.

    I can't remember if they can now make adult stem cells omni-potential, or just increase their potential to add just a few more cell types.
  • by ambulatorybird (1151807) on Tuesday September 04, 2007 @10:50AM (#20464145)
    I've had a valve replacement myself, and I believe there are two problems: (1) pig valve: those are basically like leather, and they wear out after 5 years, requiring replacement even in adults. And open heart surgery isn't normally something one wants to have on a regular basis. (2) artificial valve: blood clots form on them, requiring the patient to take anticoagulant drugs for the rest of his life.
  • by cayle clark (166742) on Tuesday September 04, 2007 @11:38AM (#20464807) Homepage

    When I was getting ready to have my aortic valve replaced, the surgeon showed me a porcine valve; in appearance it is nothing like leather, but rather an incredibly thin and flexible structure. The aortic valve is not like a flap valve, but more like three little plastic grocery bags hung from the sides of a pipe. When blood flows one way, the leaflets collapse against the wall; when it flows the other way, whap, they fill up and block the tube.

    There is no rejection problem with porcine or bovine heart valves because everything except the collagen has been chemically leached out of them; there's no distinctly cow/pig cell material left for the human immune system to react to. Same for a human-tissue replacement valve (harvested from a cadaver). Nevertheless, I think a lot of people opt for the mechanical valve (and a lifetime of coumadin) because of the "ick" factor.

    The reliability figures I got from researching medical journals was that my porcine valve should last 15 years (not 5). At the time (2002) I told the doctor, "Great, by the time I need another, they'll be able to grow it from my own cells." I am just delighted this is proving to be true!

    p. s. I also predicted that by 2017 they would be installing new valves using minimally-invasive, arthroscopic surgery -- not opening the chest like a book. There has been progress on that front, too...

  • Re:Whole heart next? (Score:3, Informative)

    by Dausha (546002) on Tuesday September 04, 2007 @12:09PM (#20465277) Homepage
    "It's flamebait because it's written in an angry tone and is 'baiting' people to start a flame war."

    It wasn't meant in an angry tone. This is exactly a question, raised 1.5 years ago in my law school Health Law class, somebody else posed to a PhD Bio-ethicist. He avoided answering the question, and I thought somebody here could pose an answer. Whenever somebody's right of autonomy is stripped and the person reduced to property status, we call it slavery. (Voluntary renunciation of autonomy would be indentured servitude.) Arguably, the embryo is a person (or would be left to his one devices). Destroying the embryo to create stem cells is not voluntary, and it reduces the embryo to mere property. Thus, how is it not slavery?

    The great question is "when does life begin?" The bio-ethicist argued after 21 days, and he based his argument on our decision point for when somebody is dead (e.g. brain activity, not "mostly dead/all dead"). My question to him was "what happens if we harvested all embryos before day 21?" (An obvious ad absurdium argument, but it underscores the distinction between establishing "life at 21" verse "death at no-brain function.) He ended up conceding that the 21 days was arbitrary.

    As for baiting someone into a flamewar: by that definition, half of /. is flamebait. I merely asserted my view that harvesting embryos for stem cells is morally wrong and could be compared to slavery. If whomever modded me down for flamebait agreed with my view and thought it was too heated; then I would be more willing to agree with the assessment. However, as is normally the case, mods are used to censor opposing opinions. As this is normal, I have to assume that was the motive here. I assumed I would be down-modded because somebody wouldn't like my POV; but that doesn't mean I shouldn't express my view.
  • Re:Whole heart next? (Score:3, Informative)

    by Hercynium (237328) <Hercynium@@@gmail...com> on Tuesday September 04, 2007 @03:13PM (#20468145) Homepage Journal

    Embryonic stem cells however can change into anything, without any modification. They are much easier to work with, ...
    Just to put in some requisite corrections to some popular (mis) understandings...

    The clause, 'without any modification' is flat out wrong, applied to either type of stem cell.

    I'm not a stem cell researcher myself, but It's my understanding that adult stem (AS) cells are actually easier to work with. In addition they're clearly more readily available. That being said, this is all the bleeding edge of medical and life science and *nothing* is 'easy'

    ... and as of a couple of years ago they were the only option.
    I'm assuming what you mean by this statement is that 'they were the only vector for this type of treatment perceived as plausible'? Because, charitably, that's the most truthful interpretation, but still incorrect. Embryonic stem (ES) cells were known to have the potiential for breakthrough treatments at an earlier date than AS cells, but the difficulties in this research quickly led to the need for multiple vectors by which to proceed. AS cells soon became the most useful vector for developing viable treatments, and to date, viable treatments with AS cells outnumber ES cell treatments by far and continue to be safer and more effective.

    I'll concede that ES cells certainly have the most potiential for manipulation, and there are valuable things to be learned about cell development from their study. However, this manipulation is difficult, at best, and from my own research, the resulting treatments are much more difficult to apply to human patients. (Less so where somehow a patient may have his/her own ES cells available, of course, but this is currently a rare occurrence)

    God willing, (or science, if you prefer) we will soon have the break-throughs we so desperately desire for the treatment and cure to so many of the diseases you read about in the news. Whether it comes from ES or AS cells, or some other unrelated research doesn't much matter except to those who care more for politics than saving lives.

    I will freely disclose that I morally oppose ES cell research when the cells are obtained through IVF, cloning, and abortions, but that is mainly because I morally oppose those procedures. HOWEVER, my beliefs are my own, and I have no problem that other people do not share those beliefs. I only care about the truth and moral and intellectual honesty, both of which tend to be cast aside by ideologues on both sides of this particular issue.

Do not simplify the design of a program if a way can be found to make it complex and wonderful.

Working...