'Humanised' Organs Can Be Grown In AnimalsNew Scientist; Boston; December 17, 2003; by Sylvia Pagan WestphalA Position PaperEver since stem cell research has been discovered there has been many controversialarguments discussing whether or not this method is okay to use when dealing with patients.Research on stem cells is advancing knowledge about how an organism develops from a singlecell and how healthy cells replace damaged cells in adult organisms. Since it was discovered, stemcell research is coming a very long way, even though these processes probably won’t beexperimented in humans years for decades. Right now in stem cell research we are extractingstem cells from humans bone marrow and inserting them into animal fetus's before the immunesystem can learn the difference between it's own cells and foreign cells. The plan is to grow morehuman stem cells in animal organs than animal cells so we can perform organ transplants toreplace damaged organs with the animal's organs. The only problem about this, is a rejection ofthe animal portion of cells in the human body. This means that the cells in our body could attackthis new organ.Although, this therapy is still years away, the beginning processes have been started by ateam led by Esmail Zanjani at the University of Nevada. Zanjani’s team hopes that the animal-human organs they are working on will have compatible new cells that are exactly the same as apatient’s organs for fixing damaged organs. With the new research they have found, it could bepossible that they replace whole organs. The only problem about animal-human organs is thatpeople could get viruses from animals that humans don’t normally acquireThe original plan of Zanjani’s was to see prevent birth defects in unborn babies by injectinghealthy stem cells into the fetus but in the process of doing this, he found that in doing thisprocess, it could also be used to grow “humanized” organs. This idea came from the work ofFlake. He found that the human cells develop into part of the heart, skin, muscle, fat, and othertissues when stem cells are taken out of bone marrow and injected into sheep fetuses. Stem cells have two important characteristics that distinguish them from other types ofcells. First, they are unspecialized cells that renew themselves for long periods through celldivision. The second is that under certain physiologic or experimental conditions, they can beinduced to become cells with special functions such as the beating cells of the heart muscle or theinsulin-producing cells of the pancreas.In some cases, stem cells in the human liver can cluster together to make functional,human liver units. Then these human liver units can be transplanted at whole auxiliary organs.The exciting thing about this is that a blood protein produced by the liver has been detected in thehost animals' blood. This could open the door to creating fetal heart cells for therapy. Forexample, a kind of fetal heart cell called a cardiomyocyte has been shown to be especially good atrepairing hearts in rats or mice, but there is one big obstacle: at the moment the only source ofhuman fetal heart cells is human fetuses. Zanjani says it could be likely to grow a large variety of other tissues, like insulin-producing islet cells for treating diabetes. Now the team is trying to identify subpopulations ofstem cells that could improve producing one organ to another. They also said that the timing andsite of the injection of the stem cells makes a big difference.I believe that this is a great discovery in the field of genetic engineering. If Zanjani canmake all of this work, we can save so many lives. Extracting stem cells from humans andinjecting them in to sheep fetus’s to make organs that contain our identical cells would be amiracle. We wouldn’t need people to wait for organ transplants until they die. I think that it isamazing to look at how far medical science has come, and how much we have accomplished, inthis field. To think of all the different methods we have today that help save lives is astonishing.It’s crazy to think that we have come this far in only the last decade, I wonder how long it willtake before this research will be perfected so we can start using it on humans. We also could be able to fix birth defects even before the babies are born also by injectinghealthy stem cells in the fetus. It also states in the article that, “it might also be possible to grow awide range of other tissues, such as insulin-producing islet cells for treating diabetes.” This meansthat those with diabetes could be cured by having certain stem cells injected in that area so thatthey can make insulin for themselves. This will not only end up saving them money, but willprevent them from having to inject insulin into themselves daily. The only problem I see with this type of genetic engineering is that being able to replaceorgans and fixing people with diabetes will cause people to live longer. I’m not saying havingpeople live longer is a bad thing, but having parts our world already over-populated, this couldcreate a big dilemma. Charles Darwin, in his studies, discussed the possibility of “Survival of theFittest” and by allowing people to replace their organs, suggests that the human race has nowtaken over mother nature. Charles Darwin believed that it is important for all species to gothrough the cycle of life in order for only the stongest to survive, by allowing doctors to cure alldiseases suggests that we are allowing the sick and the weak to continue to live. This might onlycause further problems in the future if we continue to live as if normal population rules do notapply to our species.The author, Sylvia Pagan Westphal, does not state a clear opinion about her standing,although, she does state that, “Some people oppose the creation of all human-animal chimeras(organs) on religious grounds, and many more would join them if there were the slightest chancethat sheep with human brain cells might be more than just sheep.” Zanjani also says that at thelevel he is working with the animal, it’s still a sheep. This opinion only has to do with dealingwith the animals. As for stem cell research, Zanjani is still searching for the right method that will producenormal human cells,
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