动物实验,干细胞 z-bo 2020-08-25 592

　　The shortage of human organs has been plagued by medical professionals. Scientists have recently made significant progress in using pig bodies to develop human organs. Researchers have successfully combined pig stem cells with pig DNA, with the ultimate goal of cultivating human organs in pigs. However, for this method, he pointed out that doing so "will damage human dignity." The mixed embryos are transferred to the sow and allowed to develop there for 28 days, then tested and destroyed.

　　The basic idea of

　　is as follows. As such an embryo grows and matures in an adult pig, it will have organs made of human cells. These organs can be harvested and used in patient organ transplant operations.

　　On this issue, the opinions of relevant experts are very different. There are many disputes on the ethical issues and ethical boundaries of genetic research related to this breakthrough. Proponents believe that this progress will eliminate the shortage of human organ transplants. In the UK alone, more than 1,000 patients die each year waiting for organ transplants in vain. But critics blamed it on "Frankenstein Science." American scientists have conducted experiments on pig embryo related technologies and used genetic technologies related to human pancreas culture during the experiment. However, strict legal supervision means that at this stage, the embryos developed by scientists cannot exceed the 28-day limit, and the maturation and birth of such human-pig hybrid embryos are strictly allowed. Means prohibited.

　　The British government is trying to keep up with the rapid development of genetic engineering. Because these technologies will completely change the field of medicine in the near future. Prior to this, the United Kingdom was the first country in the world to allow the implementation of "three-parent babies" technology. Last week, the United Kingdom also became the first country in the world to allow the research of human embryo gene editing technology. ..

　　The latest development mentioned in this article comes from the University of California, Davis, where scientists transplanted human-pig hybrid embryos into sows. In fact, doctors have begun to talk about the feasibility of growing human organs in pigs. Therefore, the size of pig organs is similar to human organs. However, related research has encountered two insurmountable obstacles. The first is the strong rejection of the human body, and the second is the risk of contracting animal viruses.

　　But with the emergence of a new gene editing technology called CRISPR, these risks and challenges have been resolved. This allows scientists to edit DNA very precisely. Scientists have used this technology to remove part of the genes involved in the production of porcine embryonic DNA in the pancreas, creating a gap in the genetic structure of pigs. Then, the scientists injected human stem cells into the embryo. Stem cells are special cells that can grow into any human tissue. Later, after transplanting this mixed embryo into a sow, it gradually developed in the pig and had a human pancreas. After the embryo matures, it can give birth to piglets and grow up to adulthood. The pancreas can be removed and transplanted into human patients. Dr. Pablooss, who is in charge of related research, said: “We hope that this pig embryo can develop normally, but since the pancreas is almost entirely composed of human cells, the official British document issued in January this year is that if the agency can prove that there is no other method. Copying human organs, then it paved the way for similar experiments by the British Science and Laboratory Animal Council (ASC) under the British Home Office. The agency said it will obtain a three-year research permit to conduct related experiments involving the fusion of human and animal cells. However, in any case, the development of this technology is full of controversy. The main concern is that a small number of human stem cells can migrate and enter the developing brain of pig embryos, thus obtaining the second half of human characteristics. I think this is unlikely to happen, but I will seriously consider this issue. "The embryo should be taken out 4 weeks ago to examine its cell structure. Professor Walterowe of the University of Minnesota is also working on a similar project, calling pigs an ideal "biological incubator." "For example, using this method in pigs The liver raised in China will be a complete copy of the original liver, but will be younger and healthier. Therefore, after the relevant transplant, you do not need to be vaccinated. As far as inhibitors are concerned, you need to know that these drugs have side effects. "

　　Professor Raku is also worried about the proliferation of human cells into pig brain supplements. But he also said: “Whenever we grow organs, we will carefully observe the changes in the pig’s brain. If the pig’s brain becomes more and more like the human brain, then the embryo will not continue to develop.”

　　But Joseph Kui of the sports organization said: "Reproductive Ethics Review": "This kind of experiment is harmful to human dignity, and rhetoric cannot avoid this behavior. I am shocked by the arrogance and despicability of the people involved." Stuartewman of Stuartewman said: "This has entered a disturbing field. I think it is not conducive to our understanding of "human nature." Lia Baines (Julia Baines) accused the research called "Frankenstein Science" and said that this research was "a mixture of humans and animals." I created a specific embryo." This Very bad, and worse for animals. "