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Thread: Stem cell 'major discovery' claimed

  1. #1
    Senior Member KIM's Avatar
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    Stem cell 'major discovery' claimed

    Stem cell 'major discovery' claimed

    Stem cell researchers are heralding a "major scientific discovery", with the potential to start a new age of personalised medicine.
    Scientists in Japan showed stem cells can now be made quickly just by dipping blood cells into acid.
    Stem cells can transform into any tissue and are already being trialled for healing the eye, heart and brain.
    The latest development, published in the journal Nature, could make the technology cheaper, faster and safer.
    The human body is built of cells with a specific role - nerve cells, liver cells, muscle cells - and that role is fixed.
    However, stem cells can become any other type of cell, and they have become a major field of research in medicine for their potential to regenerate the body.
    Embryos are one, ethically charged, source of stem cells. Nobel prize winning research also showed that skin cells could be "genetically reprogrammed" to become stem cells (termed induced pluripotent stem cells).
    Acid bath Now a study shows that shocking blood cells with acid could also trigger the transformation into stem cells - this time termed STAP (stimulus-triggered acquisition of pluripotency) cells.
    Dr Haruko Obokata, from the Riken Centre for Developmental Biology in Japan, said she was "really surprised" that cells could respond to their environment in this way.
    She added: "It's exciting to think about the new possibilities these findings offer us, not only in regenerative medicine, but cancer as well."
    The breakthrough was achieved in mouse blood cells, but research is now taking place to achieve the same results with human blood.
    Chris Mason, professor of regenerative medicine at University College London, said if it also works in humans then "the age of personalised medicine would have finally arrived."
    He told the BBC: "I thought - 'my God that's a game changer!' It's a very exciting, but surprise, finding.
    "It looks a bit too good to be true, but the number of experts who have reviewed and checked this, I'm sure that it is.
    "If this works in people as well as it does in mice, it looks faster, cheaper and possibly safer than other cell reprogramming technologies - personalised reprogrammed cell therapies may now be viable."
    For age-related macular degeneration, which causes sight loss, it takes 10 months to go from a patient's skin sample to a therapy that could be injected into their eye -and at huge cost.
    Prof Mason said weeks could be knocked off that time which would save money, as would cheaper components.
    'Revolutionary' The finding has been described as "remarkable" by the Medical Research Council's Prof Robin Lovell-Badge and as "a major scientific discovery" by Dr Dusko Ilic, a reader in stem cell science at Kings College London.
    Dr Ilic added: "The approach is indeed revolutionary.
    "It will make a fundamental change in how scientists perceive the interplay of environment and genome."
    But he added: "It does not bring stem cell-based therapy closer. We will need to use the same precautions for the cells generated in this way as for the cells isolated from embryos or reprogrammed with a standard method."
    And Prof Lovell-Badge said: "It is going to be a while before the nature of these cells are understood, and whether they might prove to be useful for developing therapies, but the really intriguing thing to discover will be the mechanism underlying how a low pH shock triggers reprogramming - and why it does not happen when we eat lemon or vinegar or drink cola?"

  2. #2
    Ya, but what good will these stem cells do us? Stem cells alone will do nothing for SCI, the spinal cord is a elusive beast as I'm sure Doctor Young will Testify too.

  3. #3
    If they are pluripotent stem cells, and can indeed be guided to become only one specific kind of cell, it would perhaps be easier to re-myelinate intact axons that have become demyelinated. New neurons could also be made, which could be useful, provided they are connected to functionally relevant and correct targets. You are right though, that simply throwing stem cells at an injury will do nothing to clear the glial blockage that gets in the way of regeneration.

  4. #4
    I'm in no position to judge whether these cells are better than other types of cells… But I don't see why this isn't great news for the field. Anythiing that accelerates research provides some sort of excitement… Can't hurt us. Melton knows his field.

  5. #5
    I am not sure that this is a "game-changer". Assuming that these results are confirmed by other laboratories, this discovery provides one additional source of pluripotent stem cells amongst several other already available sources. For example, embryonic stem cells (ESC) are one source, induced pluripotent stem (iPS) cells is a second source, CD133 cells from umbilical cord blood and bone marrow is a third source, Muse cells are a fourth source, placental cell are a fifth source, and now STAP cells are a sixth source. The attractive aspect of STAP cells is that they can be induced from fibroblasts by simply bathing the cells in low pH (acidic) fluid. If it were really this easy, we would be seeing a lot more pluripotent stem cells than we have to date. To tell you the truth, I am skeptical. So, I will wait to see the full paper before commenting further.

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    [SIZE=13px]"The team haven't just made pluripotent cells like embryonic stem cells," says José Silva from the University of Cambridge, "they appear to have made totipotent cells." This means the cells have been rewound to a state with even more flexibility than pluripotent cells, which means they should be easier to manipulate. The only cells known to be totipotent – able to form an embryo and a placenta – in the body are those that have only undergone the first couple of cell divisions immediately after fertilisation. "They are like precursors to embryonic stem cells," says Silva.[/SIZE]

    http://www.newscientist.com/article/...2#.UumURPko7IU

  7. #7
    The large question is whether these cells survive long enough to manipulate for the different types of research one might want to do. Rumors are that the answer is "not long" but I am not able to get reputable confirmation.

  8. #8
    Haruko Obokata, the lead author of the paper, works at RIKEN Center for Developmental Biology at Kobe. RIKEN is sort of like the Argonne National Laboratory or Fermi National Laboratory in the U.S., funded by the government but devoted to biology and stem cells. According to the article in the Nature issue that described the work, she first got the idea that stressing the cells would make them pluripotent when she noticed that stem cells are typically smaller than other cells and that if the cells were squeezed through a capillary tube, they would shrink in size until they were comparable in size to pluripotent stem cells. So, she tried to reduce the sizes of the cells by using stressors, i.e. heat, starvation, and high calcium environment. While these stressors did coax the cells to show pluripotency markers, the cells themselves did not really produce that many labelled cells when injected into embryonic mice. Obokata eventually tried pH and worked very hard over 5 years to gain acceptance the idea. She said that her manuscript was rejected many times. She started to work with Charles Vacanti (the article is wrong by the way when it claimed that Charles Vacanti is at Harvard... it shows you that the writer of the article does not know the people involved because Charles Vacanti works at the University of Massachusetts and his brother Joseph Vacanti works at the Harvard, although both are famous tissue engineers who have published many papers on stem cells). Their current hypothesis is that pluripotent stem cells are created with the body's cells are subjected to deadly stress. It is interesting that Muse cells (discovered by Mari Dezawa) also are "stress-enduring" cells. In fact the term Muse stands for "Multipotent Stress Enduring" cells. Obokata did her original work on young (neonatal or newborn) mouse skin cells but used lymphocytes in her current paper. She hints that it will work on other cells with an efficiency rate of about 30%. Shinya Yamanaka (no doubt he was a reviewer of this work) has endorsed the work with the following statement: "The findings are important to understand nuclear reprogramming. From a practical point of view towards clinical applications, I see this as a new approach to generate iPS-like cells." http://www.nature.com/new/acid-bath-...-cells-1.14600. The full paper, which can be seen at http://www.nature.com/nature/journal...ture12968.html, used white blood cells that express the CD34 marker. Low-pH treated cells showed clusters of Oct4-GFP+ cell clusters. The efficiency of the method is quite impressive. For example, they would start out with 500 cells/field in the culture. On day 0 and day 1, all the cells were negative for Oct4-GFP. However, by day 2, the number of cells have fallen to about 200 cells/field but nearly 20% of the cells are expressing Oct4-GFP. By day 7, the number of cells is about 120 cells per field but over half of the cells are Oct4-GFP expressing. The cells were exposed to pH 5.7 for 25 minutes at 37 degrees centigrade. When these cells were injected into blastocysts, they ended up in many part of the animal, as well as a placenta. The chimeric embryos appear to be normal. This suggests that these cells are even more pluripotent than embryonic stem cells or iPS cells, which usually do not show up in the placenta. They further showed that the STAP cells can form germ cells (such as eggs and sperm). The full paper convinced me. This is the real McCoy. Wow.

  9. #9
    Quote Originally Posted by Curt Leatherbee
    Ya, but what good will these stem cells do us? Stem cells alone will do nothing for SCI, the spinal cord is a elusive beast as I'm sure Doctor Young will Testify too.
    These will be a good source of neural stem cells that will be useful for replacing motoneurons in people who have lumbosacral or cervical spinal cord injuries. We have been working on Muse cells as an HLA-matchable source. Note that it may put umbilical cord blood through an acid bath as well, to see what we get. This is how science progresses and we do our best to take advantage of the opportunities that the discoveries provide. Wise.

  10. #10
    Why just cervical and lumbosacral? Are cervical injuries prone to more motor neuron damage then thoracic?

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