Skin regeneration into stem cells

Dr. Tran Manh Hung

Japanese and American scientists have discovered a new technique that can turn skin cells into stem cells. This information was published by the worldwide press and mass media on Wednesday, November 21, after Dr Shinya Yamanaka, of Kyoto University - Japan and his colleagues, distributed the broadcast. Their latest demonstration of stem cell field in the Cell Journal magazine (see Takahashi et al., 'Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by De' ned Factors, 'Cell (2007), DOI 10.1016 / j.cell. 2007.11.019). At the same time Dr. James Thomson and Junying Yu, of the University of Wisconsin - Madison, USA also reported their results and success in stem cell skin regeneration in Science Journal (see Yu et al., ' Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells, Science 20 November 2007: 1151526v1 DOI: 10.1126 / science.1151526). This is a new, extremely interesting and shocking discovery around the world, especially in the medical world.

Two groups of researchers described success, which was that they were able to turn human skin cells into stem cells similar to embryonic stem cells, without using them. coming or destroying the human embryo (human embryos). This is a difficult problem, easy to be emotional and controversial over the past decade.

New discoveries

Scientists say that, with the new method they have just discovered, it is relatively simpler and less expensive to turn skin cells into stem cells, compared with the transfer technology that scientists, Ian Wilmut , used to create Dolly sheep (1996). What they do is just transplant 4 genes (the gene: the unit in the chromosome that controls the inheritance) into the skin cells. These genes will reconstruct chromosomes in skin cells, turning skin cells into stem cells that are capable of endless development and reproducing different cells, about 220 types in the body. humans, it can be heart cells, liver cells, neurons, blood or bone cells.

Until now, most scientists still think: the only way they can make stem cells easily, most likely used for medical treatments, is to make embryos. then harvest the stem cells - within a week - after the embryo has been formed. So the embryo will be destroyed in the process.

It is feasible to turn skin cells into stem cells.

Recently, two groups of Japanese and American scientists have shown that the use of skin cells to form stem cells is feasible . A year ago, Dr. Yamanaka reports that he has succeeded in transplanting four genes into mouse cells and turning them into mouse embryonic stem cells. He also demonstrated that, through tests, these stem cells could become any kind of mouse cell. He also used stem cells, the type of omnipotent stem cells (totipotent stem cells) to create other pups. (Any reader who wants to know more about the difference between almighty stem cells and pluripotent stem cells, see Tran Manh Hung's article, The Basics About Stem Cells - http://vietcatholic.net/ News / Html / 44805.htm )

After verifying the results and verifying his success, through experiments with rats, Dr. Yamanaka began experimenting with human skin cells, using the same method and technique. He thought that it would take at least a few years to find the right gene and the right environment to promote research into the use of human skin cells. However, he said, because he wanted to get results soon, he had to work 12-14 hours a day in the laboratory. Thanks to that, in just a couple of months he succeeded.

Since Dolly was born, in 1996, scientists predicted that adult cells could, in theory, turn into stem cells. But at the time, they did not know how, except to apply the cloning technique of transcription, which was used by Ian Wilmut and Keith Campbell to create Dolly sheep (See the Earth Manh Hung, Current Ethics and Biological Challenges Hanoi: Religion Publishing House, 2003, pages 33-42).

With the nuclear transfer technique , the researchers cleaved the nucleus (nucleus) of the adult cell - the ratio of the skin cell - and placed it in the egg cell, without fertilization, but its nucleus was removed. Egg cells that have been newly harvested will automatically grow as normal, as when the egg is fertilized. Just a few days later, people will see blastocysts appear, which contain stem cells. The feature of this technique is that stem cells will have exactly the same genetic material (same DNA). Therefore, scientists hope that transplanting them back to patients will prevent the cells from being eliminated by the body or the immune system because they do not have the same gene.

After success in creating new embryos by transfer technology. Scientists want to take another step, by asking the question: How can egg cells reproduce the genetic material, after receiving a new nucleus, from donated cells? Can we transform adult cells without using egg cells?

This is what prompted Dr. Yamanaka and Dr. Thomson attempted to work out which genes were used in embryonic stem cells but not in adult cells, to see if such genes could be used to alter mature cells. stem cells. Dr. Yamanaka tested by experimenting on mice, especially Dr. Thomson used human skin cells (taken from the forehead) to experiment.

Both groups have found more than 1,000 potentially suitable genes, but with such a number of genes it is difficult to determine exactly which genes actually play a major role. In that way, they continue the process of eliminating and leaving behind only about 20 genes that they think are the main genes. They then asked the question: how to turn skin cells into stem cells. They finally found four key genes, which can be implanted into skin cells into stem cells. These genes, despite their similar functions, are considered to be the main regulating genes, in order to switch off or open other genes.

The moral impediment can be overcome.

With this modern discovery, scientists can eliminate the moral problem, because they do not need to use human embryos or create these embryos by cloning method, through transfer technology. Just as they do not need to ask women to donate eggs (eggs), to use for cloning, but they can still make stem cells, which have the same genetic material as the donor. These stem cells, when used to replace tissues for patients, will not be rejected by the immune system. More importantly, according to scientists, the cells that share a genetic material, made up of patients, will help them study and learn more in the laboratory about incurable diseases, For example, dementia.

For the current new technique, the use of asexual cloning method to study specific stem cells, such as the creation of human embryos to harvest stem cells, would not be necessary. For that reason, scientist Ian Wilmut, considered the father of nuclear transfer technology (nuclear transfer technique) and the creator of Dolly sheep (1996), writes in a newspaper article - The Telegraph - released in the United Kingdom, on November 16, 2007 publicly announced that he gave up the cloning method because he himself pioneered to create Dolly sheep.

Dr. Tran Manh Hung (LJ Goody Bioethics Center)
phtran-ljgbc@iinet.net.au