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Thread: Some Stem Cells Don't Work

  1. #1
    Banned Faye's Avatar
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    Some Stem Cells Don't Work

    Yet another study showing that bone-marrow derived stem cells do not replace damaged tissue:

    Some Stem Cells Don't Work

    Those from bone marrow didn't regenerate

    THURSDAY, Dec. 2 (HealthDayNews) -- Bone marrow-derived side population stem cells appear to have limited potential for regenerating injured cardiac and skeletal muscle, says a University of Chicago study in the Dec. 1 issue of the Journal of Clinical Investigation.

    The researchers transplanted such stem cells from normal male mice into female mice that lacked delta-sarcoglycan, an animal model of muscular dystrophy and cardiomyopathy. The researchers wanted to find out if the stem cells would be recruited to heart and skeletal muscle to restore delta-sarcoglycan expression.

    They found that the stem cells can produce delta-sarcoglycan, but only to a small degree. This suggests that these stem cells offer limited potential for regeneration of heart and skeletal tissue.

    Many previous studies have found that stem cells can travel to injured skeletal and cardiac muscle, but marker proteins have not been able to definitively distinguish between donor and recipient cells. This raises the possibility that the recipients' own cells, not donor stem cells, have been responsible for observed regeneration of heart and skeletal muscle.

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    ~It's troubling that exit polls and vote totals were so far out of whack. "I've spent my whole life in marketing. The difference is clearly beyond any sampling variability. ... The community of statisticians and media experts need to not let this be dropped"~ Bill Hawkes, a retired A.C. Nielsen Co. statistician.

  2. #2
    Originally posted by Faye:

    Yet another study showing that bone-marrow derived stem cells do not replace damaged tissue:
    Sounds just like an anti-ESC proponent applauding failed ESC research. We need research into both.

    I am going to speak in generalities here.

    Stem cells will not work for everyone... at least not in their current form. Adult? Embryonic? It doesn't matter. Neither will work for everyone until more is understood about what characterizes the stem cell phenotype.

    Why? Take an embryo created using SCNT, where an egg has it's nucleus removed and then replaced with the nucleus of a somatic cell. Prior to enucleation, the egg had the proper genes "turned on" in the nucleus and the corresponding proteins in it's cytoplasm to allow for fertilization and embryonic development.

    The key to proper development lies in having the correct "matching" between expressed genes and environmental cues, especially those found in the cytoplasm. You can have one or the other, but without the proper correlation between genes and cues, chances are that all you will be left with an ineffective cluster of cells.

    What needs to be done? The genes that define the stem cell phenotype need to be discovered. The sequence of cues that allow a stem cell to differentiate [or transdifferentiate] into a specific cell type need to be determined. Without both of these, ESC is all a crap-shoot.

    -Steven
    ...another turning point, a fork stuck in the road

  3. #3
    I agree with Steven. We must be careful about assuming that all stem cells are alike or do the same things. It is almost like assuming that all drugs are alike. We should not even assume that all bone marrow stem cells are alike. The main problem with bone marrow right now is that we don't have a good way of identifying the stem cells and the way they have been cultured make a big difference in how they behave after transplanatation. There will undoubtedly be many "failed" experiments because there is no "standardized bone marrow stem cell" yet. While several studies to date have suggested and bone marrow stem cells accelerate cardiac repair, no study has shown that bone marrow stem cells produce cells that replace cardiac cells. Likewise, there have been, to my knowledge, no credible study showing that bone marrow stem cells can replace neurons. In fact, there are now questions whether bone marrow stem cells can produce functional neurons in culture, as reported by Ira Black. We are still in the early stages of this treatment and more research is needed to demonstrate that bone marrow stem cells can transdifferentiate consistently into neurons or other kinds of cells. Personally, I believe that they can and the task to how to make them do so consistently. Wise.

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    Banned Faye's Avatar
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    Originally posted by Wise Young:

    While several studies to date have suggested and bone marrow stem cells accelerate cardiac repair, no study has shown that bone marrow stem cells produce cells that replace cardiac cells. Likewise, there have been, to my knowledge, no credible study showing that bone marrow stem cells can replace neurons. In fact, there are now questions whether bone marrow stem cells can produce functional neurons in culture, as reported by Ira Black. We are still in the early stages of this treatment and more research is needed to demonstrate that bone marrow stem cells can transdifferentiate consistently into neurons or other kinds of cells. Personally, I believe that they can and the task to how to make them do so consistently. Wise.
    I agree that it might be possible that bone marrow stem cells can transdifferentiate into functional neurons even though Dr. Weissman would disagree.
    It's also possible that using ESC to generate functional neurons may be a lot more efficient.
    Only more research into both ESC and ASC will be able to tell.

    ~It's troubling that exit polls and vote totals were so far out of whack. "I've spent my whole life in marketing. The difference is clearly beyond any sampling variability. ... The community of statisticians and media experts need to not let this be dropped"~ Bill Hawkes, a retired A.C. Nielsen Co. statistician.

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    Banned Faye's Avatar
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    Originally posted by Steven Edwards:

    Originally posted by Faye:
    Yet another study showing that bone-marrow derived stem cells do not replace damaged tissue:
    Sounds just like an anti-ESC proponent applauding failed ESC research. We need research into both.
    Why would I be applauding failed ASC? I have been a member of SCS ( Spinal Cord Society ) for almost 7 years now, and have donated a substantial amount of money to them. As you know they have only worked on autologous stem cells/ ASC derived from one's own body. So why would I want ASC to fail?

    My above statement was merely made to indicate that this is not NEW news. That these kinds of reports have repeatedly been made about ASC, in particular bone marrow derived stem cells.

    ~It's troubling that exit polls and vote totals were so far out of whack. "I've spent my whole life in marketing. The difference is clearly beyond any sampling variability. ... The community of statisticians and media experts need to not let this be dropped"~ Bill Hawkes, a retired A.C. Nielsen Co. statistician.

  6. #6
    Originally posted by Faye:

    Why would I be applauding failed ASC? ... So why would I want ASC to fail?
    Who knows? I don't believe you want ASC to fail, per se, but I do believe [based on your posts for the past year or so] that you enjoy news like this because it can be used to essentially say "A failure! This is why we need ESC!"

    The stem cell debate has been framed by the antagonists so that any debate on the issue is ineffective, in my opinion. The anti-ESC groups have been promoting all the positive results of ASC research. In response, it seems that the pro-ESC groups have chosen to point out the failures of ASC research to justify the "need" for ESC research. In effect, the debate has shifted from the potential of stem cells to cure diseases to which "type" of stem cell is best according to today's research.

    This shift away from the real issues has done more to hamper the public debate over stem cell research than any policy Bush has instituted. This shift has been a disservice to America and to every person that stem cell research has the potential to help.

    When advocating for stem cell research, legislators always want to know "What promise has it shown in the labs? What diseases has it cured or treated?" At the current time, almost any promising claim shown in the lab can be countered by those who oppose such research because of a report showing contradictory results.

    Why does this situation exist? Science is based on a strong, dependable foundation of knowledge. Regarding stem cells, no such foundation has been developed. The proper debate should be on the need to establish this foundation of knowledge. Without it, outcomes of experiments cannot be reliably predicted. With it, researchers will be able to develop experiments that have a much higher chance of success, which will allow effective therapies to be produced at a lower cost, at a quicker pace, and with potential side effects worked out in advance.

    Everything needs a strong foundation. The first goal is to build it. Yes, it's slower than we would like. It's also more reliable than hoping some researcher will make a serendipitous error that results in a cure.

    -Steven
    ...another turning point, a fork stuck in the road

  7. #7
    Good post Steven.

    The anti-ESC groups have been promoting all the positive results of ASC research. In response, it seems that the pro-ESC groups have chosen to point out the failures of ASC research to justify the "need" for ESC research. In effect, the debate has shifted from the potential of stem cells to cure diseases to which "type" of stem cell is best according to today's research.

  8. #8
    Banned Faye's Avatar
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    Originally posted by seneca:

    Good post Steven.

    The anti-ESC groups have been promoting all the positive results of ASC research. In response, it seems that the pro-ESC groups have chosen to point out the failures of ASC research to justify the "need" for ESC research. In effect, the debate has shifted from the potential of stem cells to cure diseases to which "type" of stem cell is best according to today's research.
    While this may be true, there is a very good reason for this:
    1. Anti-ESC groups haven't just been promoting the pos. results from ASC, they have actively distorted the "dangers" of ESC and down-played the potential of ESC
    2. Anti-ESC groups have also inflated the potential of ASC. Like the Adult Stem Cell Senate Hearing where they USED the OEG transplant by Dr. Lima as proof that adult stem cells could "cure" paralysis.

    How do you think pro-ESC groups should respond? Should they not point out the limitations of ASC?

    I think it is immoral for Anti-ESC groups to oppose ESC research based on false premises. The PRO-ESC groups are not "anti" anything and therefor are more genuine in their approach. For example you conveniently removed the part of my quote that showed I had poured money into and continue to actively support an organization ( SCS ) heavily involved in ASC only.

    Here is my complete quote again:
    Why would I be applauding failed ASC? I have been a member of SCS ( Spinal Cord Society ) for almost 7 years now, and have donated a substantial amount of money to them. As you know they have only worked on autologous stem cells/ ASC derived from one's own body. So why would I want ASC to fail?
    But a major difference is they are not anti-ESC. I admire this group because they go solo pretty much, away from the obstacle laden bureaucracies.
    It has only been through Dr. Young's influence that I've come to realize that NIH funding is extremely important at the basic science stage that ESC research still finds itself in.

    BTW I may type in a response to an article that was published about Jason in Folio Magazine titled Hell on Wheels in a separate thread ( since I probably can't find it on-line), because it so exactly expresses how I feel about the ESC/ASC "controversy". You and I have been going back and forth about this for many months and I thought you had understood once and for all that I am Pro-ASC and Pro-ESC.

    The reason we are seeing so many articles refuting the efficacy of ASC to replace damaged tissue is that so much more ASC research is taking place already. As you know NIH funding for ASC has been more than 8 times higher than NIH funding for ESC.

    I didn't want new CC members to think this was new info. Next time I will type: "This is NOT new info, but this nevertheless does again show that ASC will not replace damaged tissue."

    ****BTW that does not mean ASC cannot be useful. Most of these articles do say that SOME repair does take place after the ASC transplant through other mechanisms other than cell replacement.

    ~It's troubling that exit polls and vote totals were so far out of whack. "I've spent my whole life in marketing. The difference is clearly beyond any sampling variability. ... The community of statisticians and media experts need to not let this be dropped"~ Bill Hawkes, a retired A.C. Nielsen Co. statistician.

    [This message was edited by Faye on 12-07-04 at 09:48 PM.]

  9. #9
    As a preface, I am not trying to "go rounds" with you about this. The portion of my reply that you quoted was just an observation, with nothing personal meant. I have just decided to become more vocal.

    Originally posted by Faye:

    How do you think pro-ESC groups should respond? Should they not point out the limitations of ASC?
    The truth is always a good choice, but non-confrontational is best. By pointing out the limitations of ASCs, you are playing right into their hands and allowing them to frame the debate as ASCs vs ESCs. When they speak out against ESCs and in support of ASCs, call them on it. "Sir [or mam], while we may disagree about the relative importance of adult stem cells and embryonic stem cells, we do both agree that ASCs have enormous potential. Would you support a bill that provided funding for adult stem cell research? If so, what steps have you taken and what steps will you take to get such a bill before Congress?"

    Explain the importance and the need of establishing a firm foundation of knowledge for future research, whether it be ESC or ASC research.

    The reason we are seeing so many articles refuting the efficacy of ASC to replace damaged tissue is that so much more ASC research is taking place already. As you know NIH funding for ASC has been more than 8 times higher than NIH funding for ESC.
    It is true that ASC gets more money for research, but the failures so far are not seen as evidence demonstrating a need for ESC research by those who oppose it. Rather, it is seen as proof to support their claims. They see ASC and ESC as functionally homologous entities, therefore "If you can't do it with ASC, you won't be able to do it with ESC."

    You need to take that belief and frame your advocacy around it.

    -Steven
    ...another turning point, a fork stuck in the road

  10. #10
    Banned Faye's Avatar
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    Steven, you make some valid points. But...

    You don't think the Anti-ESC group is confontational?

    When did presenting REAL facts become confrontational?

    I actually think the presentation of half truths with statements like "ASC have already "cured" over one hundred conditions", or "ESC form tumors", are far more confrontational.

    ~It's troubling that exit polls and vote totals were so far out of whack. "I've spent my whole life in marketing. The difference is clearly beyond any sampling variability. ... The community of statisticians and media experts need to not let this be dropped"~ Bill Hawkes, a retired A.C. Nielsen Co. statistician.

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