What Are Stem Cells?
Today, many people have heard about stem cells, including the ones far from science. However, not everyone understands what stem cells are, where they come from and where stem cells live. Stem cells are called cells that do not have specialization and are able to divide while turning into any kind of tissue - skeletal muscle, neurons, blood, liver tissue, and so on. Stem cells play the role of universal ‘spare parts’ that the body uses to repair various tissues. The only problem is that with age, the content of stem cells in the bone marrow, as well as the body’s ability to produce them, plummet. The solution was found in the introduction of stem cells from the outside. But where do you get them from? The most studied source of stem cells is the bone marrow donor. But donor is not enough even for patients suffering from blood diseases.
There is another source of stem cells - an embryo of an early stage of development. Embryonic stem cells can be obtained from material obtained during abortions or as a result of in vitro artificial insemination. Embryonic stem cells are significantly more versatile than other stem cells from an adult body. However, the issue of the use of embryonic stem cells in medicine is still not well understood. Won’t they degenerate into rampant cancer cells? It is safer to use adults, or, as they are called, postnatal (received after birth) stem cells. And to get them is quite realistic, since there is a fairly safe and cheap source. This is the blood of the umbilical cord of newborns, which is very rich in stem cells. The source is almost inexhaustible. In addition, the collection of cord blood does not cause either ethical or serious technological problems. If you create a bank of samples of such blood, it can completely replace the entire bone marrow collection system for transplantation. The stem cells obtained from the umbilical cord are almost universal and can be used to treat many people suffering, as already mentioned, from a variety of ailments.
Stem cells have been explored for more than half a century. Scientists create them from ordinary adult cells, model various diseases with their help, and grow organoids for transplantation. However, therapeutic methods for using stem cells in most cases do not go beyond laboratories and clinical trials. Stem cells in organism differ from embryonic ones, because they have already slightly matured, that is, they are located in some organs and are ready to turn into the desired type of tissue. This process is irreversible. If a cell has become, for example, an epidermal skin cell, then it cannot be back stem. This was believed until 2006, when the Japanese scientist, Shinya Yamanaka, discovered a method for the genetic reprogramming of mature cells into stem cells. Of the dozens of genes that trigger the development of embryo and subsequently stop working, he identified four crucial ones. The scientist tried to incorporate them into mature mouse cells, and it worked - they acquired immature abilities. The proteins produced by these four genes are now called the Yamanaki cocktail. In 2012, for this achievement, the scientist was awarded the Nobel Prize. After successful clinical trials, Japan researchers approved the treatment of spinal cord injuries with stem cells. Given that a few years ago this method was developed exclusively on laboratory rodents, progress by medical standards is rapid. Until now, only one stem cell treatment technology has been widely practiced: bone marrow transplantation for patients with leukemia, but all in good time.
All plants and animals, including humans, have stem cells. These are immature structures that can turn into any type of special cells: blood cells, neurons, skin cells, bones, muscles, and teeth. With their help, body tissues are constantly updated throughout life. For example, intestinal mucosal cells change every week. Stem cells in theory were described at the beginning of the 20th century. For the first time, the assumption of their existence was expressed by a Russian biologist. This was experimentally confirmed in the 1960s by Canadian scientists. They subjected the mice to a lethal dose of x-rays, thus killing the hematopoietic system, and then transplanted them different types of cells from healthy individuals. So, the researchers saw that blood helps to restore bone marrow cells, and in order to start the renewal process, only one healthy cell is enough, but it must be immature.
The discovery of Yamanaki literally freed up the hands of scientists around the world and spawned a wave of research with these converting objects (they are called induced pluripotent stem cells). Biologists have taken over the idea of transplanting pluripotent stem cells into any damaged or aged organ in order to restore it. However, reality turned out to be more complicated. The implanted stem cells did not take root, died, caused side-effects, or simply had no effect.
Authors of the Cochrane Systematic Review (this body examines the scientific evidence of medical manipulations) in 2015, we analyzed data on the addition of stem cells to the patient’s own fat cells during breast transplantation. Clinics advertising this procedure claimed that engraftment is better in this case. However, analysts did not find any evidence of the positive effect of the procedure - on the contrary, they pointed to its possible danger.
At the same time, the Cochrane systematic review in 2014 noted a positive effect as a result of treatment of spinal injuries with mesenchymal stem cells, after which motor functions were restored faster. In those years, these experiments were done exclusively on rodents and, as practice has shown, their results were applicable for treating people.
Stem Cells Revolution
There is a tremendous interest in stem cells in the world, because they open the way to the treatment of many diseases: neurodegenerative, cardiovascular, diabetes mellitus, damage to the retina, hereditary issues. Scientists are exploring the possibility of growing new teeth from stem cells and repairing joints. Bone marrow transplantation is now used to treat blood diseases all around the world.
Any multicellular organism grows from a small colony of stem cells. If it is divided, for example, into two parts, a complete embryo will form from each. Embryonic stem cells can infinitely divide in vitro. This property is used to create cell cultures for laboratory experiments and testing future drugs. Unlike stem cells in the adult body, which serve to renew a specific organ, embryonic stem cells can turn into any type of cell. For this, they were called pluripotent, that is, cells with numerous capabilities.
Technically, embryonic stem cells can be obtained even in an adult. To do this, one needs a donor cell. The nucleus where the DNA is stored is removed from it and the nucleus of another person’s cell is placed there. Then a cell is forced to divide and an embryo is obtained, the development of which is stopped at an early stage. This was first demonstrated in 2018 in the U.S. So far, these achievements had no practical application, since experiments with embryonic cell cultures are allowed exclusively for research purposes.
Stem Cells in Canada: Law and Practice
Despite the fact that such procedures do not have any approval from the authorities, in Canada there is still a practice of treating patients with stem cells.
All stem cell therapies are considered drug treatments. This means that the distribution and use of this product requires authorization from the Department of Health. None of the stem cell injection procedures practiced today in private clinics have such approval.
Stem cells are a unique category of cells in the human body that can be transformed into a number of cells of various organs. Scientists are studying the potential use of this material for regeneration processes, such as cultivation of tissues and organs, as well as cure of diseases. So far, however, only experiments are being conducted. None of the procedures has yet been officially approved, with the exception of bone marrow transplants for the treatment of cancer or blood diseases.
In Toronto, there is an example of the treatment history of a woman suffering from severe knee pain. Using the Internet, she found clinics that really offered stem cell treatments and could help her with the disaster. After completing the online registration assistance, she got the opportunity to meet with an orthopedic surgeon. All procedures took about an hour. They were carried out in medical offices. Doctors removed particles of the patient’s bone marrow or adipose tissue, placed them in a centrifuge, and then injected the material with a syringe into knee, thigh or other part of the body of the same patient. In the case of a woman from Toronto, the doctor diagnosed arthrosis and recommended injections. The cost of an injection in one knee was about $3100, and in both - $3500. This patient, however, refused injections. A doctor at another clinic stated that injections were 100% effective. However, he did not provide any scientific information confirming that statement. In another case, Rick McGregor went through an injection procedure on both knees. It cost him $1700, but he, in his own words, did not feel any improvement. He had been waiting for six months. For a short time, maybe it was a little better, but it did not last very long.
According to opinion of representatives of the committee on medical law the University of Alberta, procedure involving stem cells is a complex scientific complex. One cannot just inject cells into his knee and hope that it works. Some scientists believe that this practice should be stopped immediately.
To this day, stem cells have not been tested in the usual manner in this case - on two groups of patients, one of which is administered the desired drug, while the others receives a placebo. But some patients and doctors insist that injections save people from pain. Ms. Engel traveled twice to the United States and spent more than $5000 on two sets of injections into her sore knee. So, she claims that the injections helped her, and is thinking about a third trip, however, now she needs to save up money. This patient is confident that her condition has improved by half. However, sceptics are not sure of the effectiveness of the procedures and find other possible explanations for improvement. This, they say, could be the result of a natural retreat of the ailment or the same placebo effect.
One way or another, stem cell injections seem to fall into the gray area of the law. The Canadian Ministry of Health cannot regulate the practice the popularity of which is only growing. None of the professional medical colleges have yet developed a common position or rules. Equipment for the collection of this material is bought directly from the manufacturer, and such equipment is licensed. But the use of stem cells does not have any licenses, with the exception of permits for official clinical trials.
However, in Ottawa it is said that any such procedure must receive appropriate approval before application. Strange, but true, the Ministry of Health is not trying to take any punishment actions to stop this practice. While there are no such permissions or clear prohibitions, injections continue. Some experts have expressed concern that excess cells may cause, among other things, cancer.
Indeed, if the introduced material promotes cell growth (and this is precisely the purpose of the injection - to stimulate the growth of healthy cells in the knee or shoulder), it should be understood that theoretically there is a risk that stem cells will cause the growth of a malignant tumor. In official clinical tests, by the way, there is a special form in which such a risk is indicated.
So far, no serious problems regarding injection into the joints have arisen. But three women in the United States lost their vision after they were injected with stem cells in their eyes to cure macular degeneration (macular degeneration, degenerative changes in the retina). In at least one country, Australia, which is very similar to Canada in many legal respects, it has been banned from directly promoting the use of stem cells.