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Non-Rejectable Tissue

  1. Apr 27, 2005 #1
    okay I didnt really understand that but what I was wondering was: Can you replace brain tissue thats been damaged or destroyed somehow, since the body (apparently. I had a little bit of trouble understanding that last post) won't reject brain tissue?
    Last edited: Apr 27, 2005
  2. jcsd
  3. Apr 27, 2005 #2


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    the brain has a barrier that limit the element enterring the central nervous system (CNS). Usually, cell that play a role in the immune system do not enter the CNS. The CNS has its own immune system (more or less). Therefore, the Major Histocompatibility Complex (MHC) recognition will not play a role when transplanting tissue in the CNS. The rejected tissue is due to non-self MHC that is recognized by the immune system.
  4. Apr 27, 2005 #3


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    While the brain does enjoy a certain isolation from immune surveilance, it is sometimes called an immune priviledged site, this does not necessarily facilitate the type of transplantation you describe. One of the major problems, that we have addressed in other threads, is that physically reconnecting all the circuits in the replaced piece of brain is currently not possible. These connections are critical not only for function of the transplant but also for survival. Chemicals such as growth factors are required by many cells of the brain and are supplied by their respective targets. If these factors can somehow be supplied the transplant might be able to re-establish the correct connections and potentially re-assume function. However this does not mean that the brain is completely devoid of immune activation. Check this article for a review of brain tissue/cell tranplantation and the associated immune system problems.
  5. Apr 27, 2005 #4
    The only reason I brought it up was I thought that if you put part of someone's brain in the brain... that the brain would sort of automatically connect to it..that that brain tissue would become a part of the brain just like any other tissue, and that it would be looked after by the brain like any other tissue

    if that makes sense...sorry if it didnt
  6. Apr 28, 2005 #5


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    It's not a bad thought, and is a fundamental premise behind certain tranplantation technologies that are being investigated. However, it turns out to be more complicated than: replace brain region A with donor piece, hope for new connections to be made and avoid immune system activation. A search on PubMed will bring out more aspects of this topic than can be covered here.
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