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Biotech Medicine Science

Non-Embryonic Stem Cells Developed From Skin Cells 175

juliangamble writes "Scientists reported Thursday they had developed a technique that can quickly create safe alternatives to human embryonic stem cells, a major advance toward developing a less controversial approach for treating a host of medical problems. The researchers published a series of experiments showing they can use laboratory-made versions of naturally occurring biological signals to quickly convert ordinary skin cells into cells that appear virtually identical to embryonic stem cells. Moreover, the same strategy can then coax those cells to morph into specific tissues that would be a perfect match for transplantation into patients."
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Non-Embryonic Stem Cells Developed From Skin Cells

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  • by BJ_Covert_Action ( 1499847 ) on Friday October 01, 2010 @03:43PM (#33764004) Homepage Journal
    I thought one of the huge advantages of embryonic stem cells was that, once gathered, they could effectively be reproduced or cloned or something indefinitely without the need to gather more. Is that the case with these new cells? Or am I completely off base in the first place?
    • by Attila Dimedici ( 1036002 ) on Friday October 01, 2010 @04:02PM (#33764258)
      Theoretically, both adult and embryonic stem cells can be reproduced indefinitely.
      • by T Murphy ( 1054674 ) on Friday October 01, 2010 @04:24PM (#33764512) Journal
        (Last I heard) Yes and no. Your chromosomes have telomeres on the end- basically a timer. Each time the chromosome is replicated, the telomeres shorten, so eventually the chromosome cannot replicate any longer. Embryonic stem cells and cancerous cells are alike in that they get around this (an enzyme telomerase at least has a role with ESCs). It may be the case that researchers have found a way to make adult stem cells replicate without telomere shortening while avoiding cancer-inducing qualities, but it would be more complicated than simply letting ESCs do their thing.

        Regardless, they're basically trying to turn cells into a benevolent cancer, so research like this that helps us understand how the cells morph into different types is helpful no matter whether ESCs or ASCs win out in the end.

        NB: I only know so much about this, so if you can explain better/correct me, feel free to post a +5 informative.
      • by BJ_Covert_Action ( 1499847 ) on Friday October 01, 2010 @04:26PM (#33764554) Homepage Journal
        That's not what I've read. From their respective wikipedia articles:

        Embryonic stem cells: [wikipedia.org]
        "Additionally, under defined conditions, embryonic stem cells are capable of propagating themselves indefinitely."
        Adult stem cells: [wikipedia.org]
        "Self-renewal which is the ability to go through numerous cycles of cell division while still maintaining its undifferentiated state." (emphasis mine)

        So, it seems that while embryonic stem cells can reproduce indefinitely, adult stems cells can reproduce numerous times, but not indefinitely. Sure, maybe that number that numerous implies is very high, but that is still distinctly different than indefinitely. That's why I asked the question in the first place... Even one of the doctors in the article talks about how embryonic stem cells are still necessary for research purposes due to their unique traits (I am wagering one of those traits is their reproducibility).
        • by Nemyst ( 1383049 ) on Friday October 01, 2010 @04:47PM (#33764804) Homepage
          I believe you're reading too much out of a single line. If the cell's maintaining its undifferentiated state, then you can easily show that it'd be able to divide itself indefinitely. I'm not a biologist or a physician, but I'm pretty sure that, at this point, we still don't know much about what could happen in either embryonic or adult stem cells after a lot of divisions as part of a therapy.
    • by Defenestrar ( 1773808 ) on Friday October 01, 2010 @04:03PM (#33764270)

      Yes - that is the case with these new cells. They are made pluripotent - able to be reprogrammed into many other types of cells.

      These advances from skin cells (& fat and a few others...) have the awesome benefit of matching the donor's DNA (not true with embryonic - thus it's likely to have rejection issues with something like new organs).

      It also allows (in most cases) for us to avoid that sketchy issue of how many living human cells crosses the threshold into human life (inheriting inalienable human rights). (Or how many types interacting, or whether you need nerves, or brain stem, heartbeat, etc...)

  • telomere tail? (Score:3, Interesting)

    by v1 ( 525388 ) on Friday October 01, 2010 @04:09PM (#33764338) Homepage Journal

    I wonder though, if they don't find a way to lengthen the telomere tail on the cell's dna, it's age won't be reset. You can't just take anyone's skin cells and make stem cells from them, if they're older generation cells the telomere tail will be short and the cell culture's lifespan will also be short.

    • by Nethemas the Great ( 909900 ) on Friday October 01, 2010 @04:23PM (#33764484)
      For the sake of those of us that work with silicon instead of carbon what precisely would be the downfall of this? It was my understanding that cells have essentially a programed lifespan but as these cells age they split thus producing their replacement which lives out its lifespan, rinse repeat...
      • by publiclurker ( 952615 ) on Friday October 01, 2010 @04:28PM (#33764582)
        I work with bits instead of carbon goo, but I think there would be a problem if the cells used for gene therapy were to wear out too early. I would imagine that getting the cells to reproduce rapidly in order to use them would take up some of the existing telomers.
      • by zero_out ( 1705074 ) on Friday October 01, 2010 @04:59PM (#33764944)
        The telomere tail is kind of like the photocopy degradation. As cells split, these tails grow shorter and shorter. Eventually, the DNA becomes a bit wacky, unstable, and dangerous. When a cell splits, both resultant cells are slightly degraded from the previous state. It's like making two photocopies (generation 2) of a document, then throwing away the original (generation 1). Then you make two copies (generation 3) of each copy, and throw away the previous ones (generation 2). Repeat several thousand times.
    • Re:telomere tail? (Score:3, Informative)

      by phantomfive ( 622387 ) on Friday October 01, 2010 @04:30PM (#33764600) Journal
      Telomerase [wikipedia.org] does exactly that. A lot of work and discovery has been done in this area since 1973, I would suggest anyone who has an interest to at least read the relevant areas in wikipedia and clear up some misconceptions.
    • by slew ( 2918 ) on Friday October 01, 2010 @04:33PM (#33764648)

      Or maybe induced pluripotent stem (iPS) cells which are reprogrammed, acquire more telomere transcripts which elongate the telomeres... Or maybe not... Who really knows for sure...

      http://www.cell.com/cell-stem-cell/abstract/S1934-5909(09)00002-2 [cell.com]

      Summary
      Telomere shortening is associated with organismal aging. iPS cells have been recently derived from old patients; however, it is not known whether telomere chromatin acquires the same characteristics as in ES cells. We show here that telomeres are elongated in iPS cells compared to the parental differentiated cells both when using four (Oct3/4, Sox2, Klf4, cMyc) or three (Oct3/4, Sox2, Klf4) reprogramming factors and both from young and aged individuals. We demonstrate genetically that, during reprogramming, telomere elongation is usually mediated by telomerase and that iPS telomeres acquire the epigenetic marks of ES cells, including a low density of trimethylated histones H3K9 and H4K20 and increased abundance of telomere transcripts. Finally, reprogramming efficiency of cells derived from increasing generations of telomerase-deficient mice shows a dramatic decrease in iPS cell efficiency, a defect that is restored by telomerase reintroduction. Together, these results highlight the importance of telomere biology for iPS cell generation and functionality.

    • by nashv ( 1479253 ) on Friday October 01, 2010 @04:35PM (#33764680) Homepage

      Except of course, telomeres are shortened with each division, because as cells age and approach the so called "Hayflick limit" [wikipedia.org] of about 45 divisions, they stop producing the enzyme telomerase [wikipedia.org], which extends telomeres. Cancer cells produce telomerase in substantial quantities, and thus can divide ad infinitum.

      The reprogramming done to produce stem cells is very high-up in the genetic control hierarchy, and likely also causes them to keep producing the telomerase. This is precisely why 1 fertilized zygote can actually reach a whole organism without banging against the Hayflick limit. In fact, telomerase production is one of the markers of being a "stem cell".

  • Victim of Language? (Score:5, Informative)

    by WeatherGod ( 1726770 ) on Friday October 01, 2010 @04:10PM (#33764350)

    While, I welcome any and all advances in the field of stem cells, I often wonder if the controversy around embryonic stem cells is mostly a product of language. As I understand it, the names "embryonic" and "adult" refers to where in the life-cycle of the stem cell it is in. It does not describe the source of the cells. Notice that even babies can have adult stem cells.

    In cloud physics, there is a concept of a embryonic cloud drop. It is merely a label for a cloud droplet at the beginning of its life cycle, before it grows or evaporates.

    So, are many people having problems with embryonic stem cells because they believe that it comes from an embryo instead of a zygote? Would public opinion be different if people understood this distinction? Would they care?

    • by jgtg32a ( 1173373 ) on Friday October 01, 2010 @04:13PM (#33764388)
      True it does refer to the life cycle of the cells but at the same time there is really only one source for embryonic stem cells, which is human embryos.
      • by WeatherGod ( 1726770 ) on Friday October 01, 2010 @04:44PM (#33764774)
        Let me put it a little bit differently. Is there a general lack of controversy around adult stem cells because of the name? Note, I am referring only to public opinion, which is composed mostly those who are not knowledgeable on the subject and have not thought more than five seconds about the subject. It is a completely different story when we talk about those who actively debate, ponder upon, and inform themselves with information on the topic. Semantic differences are relatively unimportant to them (regardless of their opinion on the matter).
    • by MozeeToby ( 1163751 ) on Friday October 01, 2010 @04:15PM (#33764414)

      I supposed blastocystic stem cells is too hard to say, otherwise you might be on to something.

    • by T Murphy ( 1054674 ) on Friday October 01, 2010 @04:36PM (#33764690) Journal
      No, the problem of embryonic stem cells and adult stem cells is with ESCs you must destroy a (potential) life, while you can harmlessly remove ASCs from just about anyone. The debate is either "the ends justify the means" or "right to life starts at point X", not a misunderstanding of the terms embryo/zygote.

      (I'm just clarifying where the lines are commonly drawn, I'm not interested in yet another "lets flame at each other and get nowhere" "debate")
      • by WeatherGod ( 1726770 ) on Friday October 01, 2010 @04:49PM (#33764840)
        Right, to you and me, this is where the lines are drawn. But I am talking about the kinds of people that you in Jay Leno's "Jaywalking" segment. The kinds of people who can not be bothered with any in-depth analysis of the topic because they have too much other stuff to deal with. Specifically, is there an issue with "first impressions" setting the tenor of a person's stance?
        • by T Murphy ( 1054674 ) on Friday October 01, 2010 @05:10PM (#33765088) Journal
          ... and these are the same people who won't see the difference between a zygote and embryo. I don't expect they'll change their minds with a 5 minute science lesson (of course they'd either ignore the lesson, or get confused and agree with you because you sound smart, so I expect it's a moot point). Now, many of these people have flimsy morals (they're pro-abortion, but only if they don't have to see the baby's heartbeat on the ultrasound, or they're against ESC research unless it's their kid dying in the hospital), so trying to get a true answer might not be a viable task.
      • by IICV ( 652597 ) on Friday October 01, 2010 @08:28PM (#33766906)

        Yeah that poor embryo, you're destroying it in order to extract some stem cells. Pity it won't go on to live the long and fruitful life in a biohazard disposal bin that was originally planned for it.

        Or did you think that we make embryos specifically to extract stem cells from them? They come entirely from fertility clinic leftovers that would otherwise be thrown away.

      • by BlueParrot ( 965239 ) on Saturday October 02, 2010 @11:29AM (#33770336)

        No, the problem of embryonic stem cells and adult stem cells is with ESCs you must destroy a (potential) life

        It's not really true though. The ESCs are typically harvested from left-over fertilized eggs from fertility treatment. Normally those cells would be incinerated. Your claim makes it sound as if one is destroying an embryo which would otherwise become a human, which simply is not true. You may be true in some technical manner, depending on how you interpret your statement, but most people who don't already know what is going on will probably have quite a different reaction if they knew the details of the matter, rather than "destroy a potential life" line that you and others throw out there without much explanation of the actual circumstances.

        Basically there would not be any fuss about this at all if people actually knew what was being done, and how.

    • by bflong ( 107195 ) on Friday October 01, 2010 @04:46PM (#33764792)

      For those that believe that a human life begins at conception, there is no moral difference between an embryo and a zygote.

    • by geekoid ( 135745 ) <dadinportland&yahoo,com> on Friday October 01, 2010 @05:10PM (#33765084) Homepage Journal

      It's a product of neo-cons needing to fester rage.

      Not only are the Zygote, there zygotes that would have otherwise been thrown away.

    • by ceoyoyo ( 59147 ) on Friday October 01, 2010 @05:22PM (#33765226)

      The problem is that some people seem to think the embryos that give you embryonic stem cells are little babies when they're actually blobs of cells sitting in petrie dishes at fertility clinics that are going to be thrown in the incinerator anyway.

  • by nashv ( 1479253 ) on Friday October 01, 2010 @04:25PM (#33764534) Homepage

    This isn't new, except for the part that says quickly.

    Induced Pluripotent Stem Cells (iPS cells) [wikipedia.org] have been around for at least 4 years now [eurekalert.org]

    These guys are short-cutting the process of DNA makes RNA makes Protein, by directly providing the required mRNA, rather than inserting new required genes into adult somatic cells and then waiting for them to make the RNA and transform, as was done before.

  • by rikkards ( 98006 ) on Friday October 01, 2010 @06:03PM (#33765686) Journal

    if Bush had not limited the harvesting of embryonic stem cells if this would have been discovered. The whole lowest hanging fruit and all that...

  • by NotSoHeavyD3 ( 1400425 ) on Friday October 01, 2010 @10:27PM (#33767628) Journal
    What they did was convert them into pleuripotenet stem cells. (The long and short of it is that stem cells are cells who's job it is to make more cells. The problem is that certain stem cells can only make certain other cells. So skin stem cells can probably only make either more skin stem cells or skin cells. Pleuripotent stem cells can make any cell that appears in the adult organism. Oh for those that care the "top of the line" stem cells would be totipotent. Not only can they make any cell pleuripotent can but they can make other stuff like placenta and umbilical cords.)
  • by ScrewMaster ( 602015 ) * on Saturday October 02, 2010 @12:24AM (#33768152)

    Moreover, the same strategy can then coax those cells to morph into specific tissues that would be a perfect match for transplantation into patients.

    I think he misspelled "patents".

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