What is "Microchimerism" in immunosuppressive therapy?
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Microchimerism\n\nIn Greek mythology, a chimera is a fire-breathing monster with the head of a lion, the body of a goat, and the tail of a serpent. In biology, a chimera is an organism consisting of tissues whose cells derive from two or more genetic sources. An apple tree, for example, can include grafts that enable it to produce a variety of apple types. In humans, such genetic mosaics reflect specific, intimate circumstances. The phenomenon is termed microchimerism because a one-cell population is typically much smaller than the other.\n\nAn organ transplant is an unnatural procedure that suddenly deposits many cells from one individual into another whose own organ has failed. It is similar to grafting in plants, and in fact, if the donor tissue reacts against the recipient's body, the condition is termed "graft-versus-host disease" (GVHD). When a transplant works, a peaceful co-existence evolves as recipient cells infiltrate graft tissue, and perhaps also as the transplanted cells alter their gene expression to modify their cell surfaces so that they are less likely to provoke the recipient's immune system. Microchimerism in transplant medicine does not refer to the transplanted material, but to small numbers of donor cells found outside the region of the transplant. For example, following transplantation of a liver, lymphoid and dendritic cells of the immune system often turn up outside of the liver, but with cell surfaces that match those of the donor, not the recipient.
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i didnt have one but a cousin who i love so much had kidney transplant approximately 10 years ago today...she's pretty much healthy but she had to take those..anti rejection meds all the time  and she has to take steroids...she gets short of breath at minimal exertion and she has cardiomegally....but she is pretty much ...healthy...and able to talk to me on the phone.....and she laughs a lot like me
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You need to talk to your physician about that.  Transplant patients are all different and needs individual assesment.
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I have never heard of a person being able to have more than one heart transplant. You are certainly a blessed man. Here are a few links to stories about people who received two organ transplants. I hope you find these stories helpful. Please try to speak with the doctor handling your case as he would be the best person to give you a prognosis.\n\nGood luck...\n\nhttp://www.sbhcs.com/services/renal/newsletter/issue_7/gift.html\n\nhttp://www.transplantweek.org/members/vol2/news/013605.htm\n\nhttp://www.aetnapharmacy.com/AP/ihtAP/r.WSIHW000/st.9339/t.32966.html
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The plasmacytoid T cell or plasmacytoid monocyte--a sessile lymphoid cell with unique immunophenotype and unknown function, still awaiting lineage affiliation.\n\nClusters of cells with a plasmacytoid appearance have been identified in T zones of human lymphoid tissue. These cells were shown to express the CD4 antigen in the absence of B-cell antigens. Thus, they were named "plasmacytoid T cells" (PTCs). Recent studies, however, have suggested a myelomonocytic origin of this cell type, which led to the designation "plasmacytoid monocytes." In order to obtain a comprehensive immunophenotype of this cell, we used frozen serial sections of lymph nodes, an indirect immunoperoxidase technique, and a broad panel of well-defined monoclonal antibodies (mAbs). On PTCs, the antigenic density was high for CD4 and CD26 antigens and low for CD2; they furthermore reacted with the mAb OKM5 recognizing an undefined antigen associated with the myelomonocytic lineage and expressed the monocyte-associated antigen CD68. PTCs expressed HLA-A, B, C, HLA-DR, and the HLA-D associated invariant chain (Ii) while HLA-DP antigens were expressed only in low amounts and HLA-DQ antigens were lacking entirely. PTCs further expressed the adhesion molecule CD11c. The absence of detectable transferrin receptor and the proliferation antigen defined by Ki-67 indicated that PTCs were nonproliferating. Other well-defined antigens confined to the T-, B-, and myelomonocyte lineages could not be detected in the target cell population. For us, antigenic equipment is still suggestive of a sessile, terminally differentiated T cell likely to exert a secretory function as yet unknown.
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It happens, but is unusual, especially in a young person.  Can occur in people who take cortisone, or other agents that suppress the immune system.  Sometimes just happens.  \nI would assume he is under treatment with anti-fungus drugs.
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Chimerism is an extremly rare condition, a person is born with the dna of two people, twins only one never made it out and was basically absorbed by the other. A mother may have a child but the chields Dna will match a sister that never existed. Very strange disorder that was reported on by 60 minutes i Believe a few months ago. you should look into it more
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www.austin.cc.tx.us/kotrla/immunohe.htm\nwww.irvingcrowley.com/cls/immuno.htm\nwww.lww.com/product/?0-397-55469-9
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I have used cryogenics to freeze lymphocytes from organ donors.  The goal in my clinical lab was to have a reference for cross-matching the donor lymphocytes (T and B cells) with the recipients blood, just in case a rejection episode occurred.\n\nRepeating the cross-match (should a rejection episode occur) allowed me to see if I made a mistake the first time around.  If I got the same negative cross-match, The surgeons would know that the rejection was not "acute", but was due to chronic rejection.  The medical approach to keep the organ recipient alive would be different for each type of rejection.\n\nBut back to your question:\n\nThe cells were preserved in a DMSO/H2O solution, and the cells and solution where placed in a special tube that would resist cracking at low temperature.  \n\nI would slowly freeze the cells over a few days to -80 degrees in a Styrofoam container.  Then I transferred the tube to a liquid nitrogen tank (I forget the temperature of liquid nitrogen, but you can google search for a quick answer, if your interested).  The cells would be good for about 10 years if stored like this.\n\nAnyway,  as I thawed the cells, I could usually depend on 50% loss of the cells (50% would die and 50% would still be viable). I knew this because I would take some of the cells and perform a "vital stain" which has a blue color to it.  If the dye was able to cross the cell membrane (making the cell blue), it indicated that the cell was dead.  If the cell membrane was able to resist the dye, it indicated that the cell membrane was intact and the cell was most likely still alive.\n\nI would say that if I froze you, and then brought you back "to life" 50% of your cells would be dead.  This surely would not be enough for you to be functional.\n\nGreat Question.  Pass on the good karma
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Genetically it is not really a suitable replacement.There are rejection problems involved in interspecies transplants.However current studies are being made into the suitability of pigs as donor material for various organ transplants.
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The word “chimera” comes from a creature in Greek mythology that had body parts from a goat, a lion and a serpent. We use the word today to describe the same basic idea.\n\nA person who is a chimera is made up of cells from different people. So some of their cells have the DNA of one person and the other cells have the DNA of another person. How do you do that?\n\nImagine that inside of a womb, instead of there being only one egg, there are actually two. If both of these eggs get fertilized by two different sperm cells, you get fraternal twins. Fraternal twins are no more related than any brother or sister.\n\nNow, imagine that instead of developing separately, these fertilized eggs actually fuse. Then only one baby would develop. This baby would have cells from not one, but two different zygotes.\n\nRemember, every zygote carries its own unique set of DNA. So the baby would have two different sets of DNA-this baby would be a chimera.\n\nMost chimeras grow up and look like everyone else. You probably wouldn’t be able to tell that the person was a chimera. Sometimes you can see patchy areas on the skin or two different colored eyes. Even these are pretty subtle changes though.\n\nThis seems weird at first. Shouldn’t a fusion of two people look pretty different? Two heads or four arms or something?\n\nThe reason this sort of thing doesn’t happen is because the fusion of the two eggs happens very early on in development. At this point, the cells haven’t started to build body parts.\n\nAfter the fusion, a given cell can’t tell that its neighboring cell actually has a different set of chromosomes. They work together anyway as if they were all created from the same zygote.\n\nChimeras are not the only people who carry different sets of DNA samples in their bodies. Mosaics also have variation in their DNA from one cell to the next.\n\n\nDNA mutations lead to mosaicism\nA mosaic, unlike a chimera, starts out with the same set of DNA in every single cell. You could look at any cell in the body and the DNA inside of it would be exactly the same as the DNA inside a different cell.\n\nAt some point during a mosaic’s life, though, his or her DNA changes in some but not all of the cells. Now, the DNA in one cell is slightly different from the DNA in the neighboring cell.\n\nThis scenario is actually very common. In fact, we are all actually mosaics.\n\nOur bodies are made up of trillions of cells. Most of these cells contain the exact same copy of our DNA. Over the course of our development and lives, however, the DNA in some of these cells can change.\n\nThere are many things in the environment that can actually change your DNA. The sunlight hitting your skin or chemicals in the food you eat are two examples.\n\nMost of the time these mutations are harmless. Only occasionally do these mutations cause problems. For instance, if a mutation affects how fast a cell can grow, the cell can become cancerous.\n\nThe changes that occur due to environmental factors are usually very small and very rare. Most of the time, only one or a few cells in your body will carry any single mutation.\n\nIt is possible, though, for a mosaic to have as many as half of the cells in his body that are different from the other half, just like in a chimera. How?\n\nIf the DNA changed very early on in your development, then more cells in your body are likely to carry the mutation. Remember, we start out from a single cell. That cell divides and then each of the two new cells divide.\n\nThis happens over and over until you end up with 100 trillion cells or so. Imagine that the first cell has divided to make 2 cells.\n\nDuring this division, a mistake was made and one cell ends up with a DNA change. Now these two cells go on to make the rest of the person. In this case, half of the person’s cells will have different DNA than what it started with.\n\nEven with these mutations, our own cells are much more similar to each other than they are to the cells fr
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Your stem cells are your own, which means exactly half of the DNA in them is from mom and half from dad.\n\nThe previous answer did a pretty good job of chimerism, but for what you want to know, I could guess that some stem cells are using x-genes and some are using y-genes, so in that way, they are kind of a mix. That would be called mosaicism, I think, which might be the term you want.
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A chimera is an animal which has (at least) two different populations of cells, which are genetically distinct and which originated in different zygotes (fertilized eggs). Chimeras are named after the mythological creature Chimera.\n\nChimerism may occur naturally during pregnancy, when two non-identical twins combine in the womb, at a very early stage of development, to form a single organism. Such an organism is called a tetragametic chimera as it is formed from four gametes—two eggs and two sperm. As the organism develops, the resulting chimera can come to possess organs that have different sets of chromosomes. For example, the chimera may have a liver composed of cells with one set of chromosomes and have a kidney composed of cells with a second set of chromosomes. This has occurred in humans, though it is considered extremely rare, but since it can only be detected through DNA testing, which in itself is rare, it may be more common than currently believed. As of 2003, there were about 30 human cases in the literature, according to New Scientist.\n\nIn biological research, chimeras are artificially produced by mixing cells from two different organisms. This can result in the eventual development of an adult animal composed of cells from both donors, which may be of different species—for example, in 1984 a chimeric geep was produced by combining embryos from a goat and a sheep. A chicken with a quail's brain has been produced by grafting portions of a quail embryo into a chicken embryo.\n\nIn August 2003, researchers at the Shanghai Second Medical University in China reported that they had successfully fused human skin cells and rabbit eggs to create the first human chimeric embryos. The embryos were allowed to develop for several days in a laboratory setting, then destroyed to harvest the resulting stem cells. Increasingly realizable projects using part-human, part-animal chimeras as living factories for producing cells or organs raise a host of ethical and safety issues.\n\nChimeras should not be confused with hybrids, which are organisms formed from two gametes (each from a different species) which formed a single zygote. All cells in a hybrid originate from this single zygote. For example, a mule is a hybrid created from the sperm of a donkey and the egg of a horse.\n\nChimeras should also not be confused with mosaics, which are organisms with genetically different cell types, but which again originate from a single zygote.
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Beta-2-microglobulin is a protein which occurs on the cell membranes of nucleus-containing cells and which forms as a light chain together with a heavy chain protein the so called HLA(human leucocyte antigen)class 1 Molecule.  occurance as a single protein in the serum following natural cell-death. higher in tumor growth, as rejection reaction after transplant, infections due to heightend activity of the immunsystem and progredient HIV. this parameter is tested in the urine because itm passed renally. normal 0.8-2.4 mg/l Serum
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T cells are one of the variety of white blood cells which are part of the immune system. The immune system as a whole learns very early to distinguish between 'self' and 'non-self' sorts of things. The test is largely like this: "is this thing I see something acceptable (ie, self)? If not, kill it." Although the question is posed and answered in a biochemical sort of way. Self is flagged, most fundamentally as near as we can tell, by the presence of Human Leucocyte Antigens (HLA) on the surface of cells. These are highly variable things, so variable that no other person anywhere is more than a tiny bit likely to have the same bunch of them on their cells. Except, of course, for identical twins. \n\nSo T-cells transplanted into you from someone else with fail the 'is this self?' test and will be attacked as 'foreign' by your immune system. They will not survive and will provide very little beneficial effect. It's called the transplant reaction and various aspects of it have earned several Nobel Prizes. \n\nMore speculatively, it may be that immune system tissues have learned to work together, and that, in each person, the exact details of just how to do so may vary. So how my T-cells work might be just enough different than yours that, even if they could survive inside you, they might not be able to interact with the rest of your immune system so as to help much. For instance, one of the things T-cells do is to talk to other immune system cells and direct their operations; if your immune system won't listen to my T-cells, much of what they'd be trying to do would be futile.  \n\nThere is quite a bit more to learn about the detailed workings of the immune system.\n\nBlood type differences (Types A, B, O are the major gropus, but there are many subgroups such as Rh (+/-), S, ...) are a simpler version of this self / non-self business, this time involving rather fewer genes and markers on blood cells. Nevertheless, there are some antibodies (yet another immune system mechanism) which use them to recognize self v non-self, and a transfusion of the wrong blood type will cause a very severe reaction, so severe as to be life-threatening.
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Only one way I know of- Kidney transplant, but then you have to worry about organ rejection.
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yes,\na person can have an alergic reaction to any protein if presented to the body in a specific way.\n\npeople are treated post transplant to immunosupressive drugs to prevent the body mounting an imune reaction to foreign material (from another person)\nhowever instances where this can happen are rare.\n\na more common occurence happens between mother and baby.  if a mother is rhesus blood group negative,  and gives birth to a rhesus positive baby.  doe to some mixing of bloods at birth,  she in effect vaccinates herself against rhesus blood.\nAny subsequent rhesus +ve babies born to this mother will be in serious danger of the mothers anti bodies destroying their cells. (so the mother has a reaction against the cells of the baby)\n\ncertain imune system related diseases such as atopic dermatitis are basically a skin manifestation of exposure to foreign alergenic material, this is commonly house dust which is the individuals own and other peoples sloughed dead skin.  the actual alergenic component to which a person reacts is ofen not found,  but this could technically be an immune reaction to another person.