Stem cells are located in Stem cells, their properties and practical applications

Olga Lukinskaya

We hear about stem cells in recent years in a very different context: they are offered to be used in cosmetic procedures and even added to creams, they learn to extract from milk teeth and the umbilical cord, they are used in the treatment of a variety of diseases. Often in the news they report new possibilities for their use, which still have to be studied in the laboratory for a long time; as a result, stem cells seem to some to be something from the future, while others think that they have already become commonplace and are used in any beauty salon. We understand what stem cells are in general, what they are often used for now, and what benefits are possible so far only in theory.

Where is it mined from
stem cells

Stem cells are so-called undifferentiated cells that can turn into different cells of the body - and in humans there are more than two hundred of them - with various functions inherent to them. For example, nerve cells or blood cells have narrow, specific tasks - and they spend all their energy on performing these tasks, without wasting it on reproduction. And new red blood cells or neurons arise from stem cells that every person has at any age. They come in different types: some are able to differentiate into only one type of cell, others into several; embryonic stem cells in early pregnancy can transform into any cell type in the body.

There are terminological disputes among scientists about whether all these cells can be called stem cells and whether the terms “stem cell” and “progenitor cell” are synonymous, but in general both terms can be used equally. We are talking about basic cells that can turn into any others - which means that if you learn how to handle them correctly, they can potentially allow you to grow new skin at the site of a burn or replace liver tissue affected by hepatitis. Unfortunately, it is not yet possible to use stem cells for such purposes - but still there are a number of serious problems that they help to solve. Stem cells can be obtained from embryos (for example, abortive materials can be used for research purposes), and in adults, their main source is the bone marrow. Stem cells are also actively isolated from the dental pulp and from the umbilical cord of newborns.

What are they used for

Stem cells have been used for several decades in the treatment of severe diseases of the blood and bone marrow, such as leukemia. The bone marrow is a hematopoietic organ; in fact, it is made up of stem cells. When it does not function or produces "defective" blood cells, one treatment option is transplantation, that is, the "replacement" of bone marrow stem cells with healthy ones. For this, both donor cells and your own can be used, if they have undergone a certain processing.

Embryonic stem cells (ESCs) are classic stem cells because they are capable of endless self-renewal and have a multipotent differentiation potential. Their source is usually primary germ cells, the inner cell mass of the blastocyst or individual blastomeres of 8-cell stage embryos, as well as morula cells of later stages.

Embryonic stem cells have the highest telomerase activity of any category of stem cells, which provides them with the ability for unprecedented self-renewal (more than 230 cell doublings in vitro; while differentiated cells divide approximately 50 times during a lifetime).

Under laboratory conditions, these cells are able to differentiate into various types of both embryonic and adult cells. They have a normal karyotype and under controlled conditions can be cloned and reproduced many times without changing their properties.

Studies have shown that ESC transplantation is effective for the treatment of pathologies that are based on dysfunction or death of specialized cell types. Thus, Parkinson's disease, caused by the progressive degeneration and loss of dopamine-producing neurons in a certain area of ​​the brain, can be successfully treated with intracerebral injection of embryonic neurons. Also, in type 1 diabetes mellitus (caused by a malfunction of pancreatic islet cells), implantation of pancreatic islet cells in the liver leads to normalization of glucose levels. With the help of ESC transplantation, other difficult-to-treat diseases can also be treated - for example, Duchenne muscular dystrophy, Purkinje cell degeneration. ESC transplantation is also effective in cases of trauma, in particular, spinal cord injuries.

At first glance, ESCs are most suitable for use in reparative medicine. However, it is well known that when transplanted into the body, ESCs are able to generate neoplasms - teratomas. Therefore, before using ESCs in cell therapy, it is necessary to carry out their differentiation in the required direction and remove from the population of ESCs cells potentially capable of leading to the formation of teratomas. Another problem that has to be overcome when using ESCs is the need to somehow ensure their histocompatibility with the recipient's body. Finally, it is difficult to ignore the ethical side of using human embryonic cells to obtain ESCs.

adult stem cells

Stem cells are present in many organs and tissues of adult mammals: in the bone marrow, blood, skeletal muscles, dental pulp, liver, skin, gastrointestinal tract, and pancreas. Most of these cells are poorly characterized. Compared to ESCs, adult stem cells are less capable of self-renewal, and although they differentiate into many cell lines, they are not multipotent. Telomerase activity and, accordingly, proliferative potential in adult stem cells are high, but still lower than in ESCs.

It is assumed that the least differentiated stem cells are in the body in a state of rest. If necessary, an irreversible process of their gradual maturation in a certain direction of differentiation is launched.

stem hematopoietic cells

Of the adult stem cells, hematopoietic stem cells (HSCs) are the most well characterized. These are cells of mesodermal origin. They give rise to all types of hematopoietic and lymphoid cells. Normally, hematopoiesis in the body, apparently, is maintained mainly due to the constantly changing small number of relatively short-lived cell clones. In vitro hematopoietic stem cells are capable of self-sustaining under certain conditions and can be stimulated to differentiate towards the same cell lines as in vivo.

For several decades, bone marrow tissues have been successfully used to treat various blood diseases (for example, leukemia), as well as radiation damage to the body, restoring the impaired functions of hematopoietic and lymphoid organs with their help. This is usually done with a bone marrow transplant; cord blood has also been used recently. The HSC population serves as a potential source for endothelial cell precursors, which makes possible the use of HSC for the treatment of coronary disease and myocardial infarction.

Stem cells of nervous tissue

Another category of cells that is currently being intensively studied is neural stem cells (NCSTs). These cells were originally found in the subventricular zone of the embryonic brain. Until recently, it was believed that the adult brain does not contain stem cells. However, experiments on rodents and primates, as well as clinical trials involving volunteers, have shown that SKNT continues to be present in the adult brain. In vitro, neural tissue stem cells can be "targeted" for both proliferation and differentiation into various types of neurons and glial cells (supporting and protective cells of the nervous tissue). Both embryonic SKNTs and adult SKNTs transplanted into the brain can generate neuronal and glial cells. Although it is not known how long it takes for neural stem cells to self-renew, they can be cultured in the laboratory for long periods.

Stromal progenitors and mesenchymal stem cells

Stromal progenitor cells and mesenchymal stem cells (MSCs) were discovered about 30 years ago. These are a kind of universal cells that are contained in the bone marrow, in a kind of depot where they are stored "in reserve". They are capable of extensive proliferation, can differentiate into many cell types, and are transplantable in vivo. If necessary, they enter the damaged organ or tissue and turn into the necessary specialized cells.

In vitro, the number of mesenchymal stem cells can increase by 100,000 times within 6–8 weeks, while they remain in an undifferentiated state. Each colony of stromal cells is a clone, that is, it is formed by the proliferation of a single cell, which has been called the fibroblast colony-forming cell (COC-F). In animals and humans under physiological conditions, the efficiency of colony COC-F cloning remains relatively stable and is an important parameter of skeletal status, which indicates the role of COC-F in the pathophysiology of bone and bone marrow defects.

Much evidence has been obtained that, in contrast to hematopoietic stem cells, bone marrow COC-Fs ​​are a local population, that is, they do not migrate from one part of the body to another and, accordingly, do not take root during infusion. It is a pity if this problem does not find its solution - after all, for the treatment of such common bone diseases as osteoporosis or incomplete osteogenesis, when it is impossible to transplant genetically modified stromal cells into all areas of lesions, the possibility of their delivery through the circulatory system looks very desirable. In general, the question of the possibility of migration of stromal cells, as well as the factors that favor it, remains open.

Stromal progenitor cells also play a very important role, providing a specific microenvironment necessary for the proliferation and differentiation of hematopoietic and immunocompetent cells in the hematopoietic and lymphoid organs. Thus, the “correction” of microenvironment disturbances can, in principle, be carried out precisely through this category of cells.

Of considerable interest for clinical use are mesenchymal stem cells, which are part of the population of stromal progenitor cells (or colon-forming stromal fibroblast cells - COC-F) of the bone marrow. Their use began with the successful treatment of ununited bone fractures with cultured autologous bone marrow stromal cells. Until now, the repair of bone and cartilage remains one of the most important areas of application of MSCs. With the help of transplantation of these cells, it was possible to achieve success in the treatment of a severe contingent of patients with false joints, ununited fractures and chronic osteomyelitis, osteoarthritis. The principles of the biotechnological methods used in this case are universal and can also be used to treat patients with bone tissue defects of various localization (traumatology, orthopedics, neurosurgery, craniofacial surgery, dentistry-implantology).

As possible carriers of recombinant DNA, mesenchymal stem cells also represent a very attractive object for genetic engineering, for the treatment of a number of degenerative and hereditary diseases.

Bone marrow cells and MSCs can also be used in the treatment of coronary heart disease, lesions of the extremities and brain, as well as for the treatment of myocardial infarction. This is another area of ​​application of MSCs, which is at the stage of preclinical trials. In animal laboratory studies and in the treatment of myocardial infarctions in humans, bone marrow SCs have been transplanted into the area of ​​infarction, either by direct injection or by intravascular injection. As a result, a real reduction in the infarct zone was achieved. However, before SC therapy in an adult organism is carried out in full, additional clinical trials and well-planned clinical studies are needed to make a final conclusion about the safety and efficacy of the proposed method.

Of particular interest are the first data showing the possibility of using bone marrow stromal cells in repair processes in the skin. In particular, studies show that after intradermal injection of bone marrow stromal cells, the regeneration of damaged skin tissue was more orderly with less undesirable consequences, which include scar formation.

It should be noted that the correct choice of the SC transplantation method remains the key to the success of treatment. A number of laboratories are also working to improve the way to purify SC populations and enrich them with early progenitors in order to create conditions for more effective cell therapy. According to the general opinion, further laboratory studies are also required to study the phenomenon of stem cell plasticity, as well as many other aspects.

As you can see, there are many hopes and expectations associated with stem cells. Perhaps the time is not far off when the discovered properties of stem cells and those that are still sealed for us today will create new prospects for the treatment of a number of serious diseases.

Why are stem cells unique?

In the process of development of the human embryo, a number of key events occur: the fertilization of the egg is followed by the so-called. crushing, the essence of which is reduced to the rapid accumulation of totipotent (i.e., capable of creating a whole organism, repeating embryogenesis from one cell) cellular material.

After about 12 cell divisions, this process slows down sharply, and the synchronism of divisions is disturbed. Transcription of the genome of the embryo begins, that is, the implementation of hereditary information. This change, known as the transition to the middle blastula, most likely reflects the depletion of a certain maternal component that is used to bind to newly synthesized DNA.

Transcription ends with the accumulation of information in the cytoplasm of these unique primary cells in the form of messenger RNAs, which determines further intrauterine development. The implementation of information is ultimately carried out by migration, specialization of cells and the formation of the main germ layers - ectoderm (source of skin cells, central nervous system, etc.), mesoderm (source of muscle cells, bones, blood, etc.) and endoderm (source of gland cells, gastrointestinal tract etc.), what happens in the process of the so-called. gastrulation.

From this point on, a limited number of unspecialized cells remain in each tissue. Such cells are called stem cells or progenitor cells, their main function is to control the process of creating an organism as a whole, transfer and implement hereditary programs.

Stem cells are undifferentiated, immature cells of the embryo, fetus, newborn or adult organism, capable of self-renewal and differentiation into various types of tissues and organs. In the body of an adult, they play the role of "regeneration machines", their goal is to maintain the morphological and functional constancy of the tissue, they have less potential than at the very beginning of embryogenesis, but are able to effectively replace the damaged elements of specialized tissue in the required volume. Almost every type of tissue has its own progenitor cells (predifferentiated cells). True pluripotent (capable of differentiating into cells of different tissues of different germ layers) cells are extremely rare under normal conditions in the body, their isolation from an adult organism at the moment without the use of cloning techniques is not possible.

In the process of aging, the amount of originally incorporated regeneration information in cells rapidly decreases, and the number of stem cells themselves decreases. An exhausted reparation system becomes ineffective - a number of diseases associated with aging occur: skin fades, cartilage elasticity decreases, bone density decreases, vascular endothelium is damaged - blood supply worsens, gradually all tissues of the body fall into conditions of reduced oxygen supply, the processes of replacing functionally active tissues with defective ones are accelerated connective stromal tissues. The impact of a number of infections, the implementation of congenital, hereditary and multifactorial diseases, chronic intoxication (including alcohol), injuries also lead to similar consequences - the body is unable to cope with the growing flow of problems and gradually dies.

The success of transplantation of human organs and tissues has opened a new era in medicine - the fundamental possibility of replacing defective tissues and organs of a patient with donor, healthy ones has been demonstrated. Unfortunately, organ transplantation remains inaccessible, is accompanied by complex surgical interventions and requires constant immunosuppression in a large volume.

Scientists around the world are intensively working on the problem of laboratory production of progenitor cells with a view to their subsequent implantation to replace dead tissues, which, according to the medical scientific community, can serve as an alternative to organ transplantation. In 1998, American scientists John Gerhart and James Thompson, for the first time in the laboratory, managed to obtain and grow cultures of embryonic stem cells and sex progenitor cells capable of completely repeating embryogenesis. Thus, humanity has a real opportunity to grow the necessary amount of "spare parts" for the body in laboratory conditions and thereby correct the consequences of a number of chronic and acute diseases. Dm. Shamenkov, Ph.D.

stem cell plasticity

Until recently, it was believed that organ-specific stem cells can only differentiate into cells of the corresponding organs. However, according to a number of data, this is not the case: there are organ-specific stem cells of adult animals that are capable of differentiating into cells of organs that are different from the organs of origin of stem cells, even if they ontogenetically belong to different germ layers. This property of stem cells is called plasticity. Thus, there is a lot of evidence that bone marrow MSCs have a wide plasticity and are able to give rise to some elements of the nervous tissue, cardiomyocytes, epithelial cells, and hepatocytes.

An alternative hypothesis of the plasticity phenomenon is that multipotent stem cells are present in various organs even after birth and are stimulated to specific proliferation and differentiation in response to local factors presented by the organ into which stem cells are recruited. There is also an assumption that stem cells are recruited to damaged organs and already there they realize their plasticity properties, i.e., they differentiate in the direction necessary for their restoration.

At the same time, it should be noted that a number of scientists question the very concept of stem cell plasticity, pointing out that the corresponding experiments were performed on pure populations of tissue-specific stem cells.

Dictionary

diploid cell(from the Greek. diplуos - double and eidos - view) - a cell with two homologous (similar) sets of chromosomes. All zygotes are diploid and, as a rule, cells of most tissues of animals and plants, except for germ cells.

Differentiation potential- the ability to transform into a variety of body cells.

Karyotype(from the Greek karyon - nut and typos - imprint, shape) - a set of morphological types of chromosomes typical for the species (shape, size, structural details, number, etc.). An important underlying genetic characteristic of a species. To determine the karyotype, a micrograph of the chromosomes of dividing cells is used.

Mesoderm- the middle germ layer in most multicellular animals and humans. Organs of blood and lymph formation, excretory organs, genital organs, muscles, cartilage, bones, etc., develop from it.

multipotency- the ability to differentiate within one germ layer.

Pluripotency- the ability to differentiate different tissues of different germ layers.

Polypotency- the ability of the adult stem cell genome to change the differentiation profile during transplantation into a new tissue of the recipient.

Stroma(from the Greek stroma - bedding) - the main supporting structure of organs, tissues and cells of living organisms and plants.

Stromal cells- cells of the connective tissue supporting structure of the organ.

Telomeres- specialized DNA-protein structures that are located at the ends of linear eukaryotic chromosomes.

Telomerase activity- the activity of telomerase, an enzyme that synthesizes telomeric DNA using a special mechanism, and thereby affects cell growth. High telomerase activity is characteristic of germ and stem cells. Once stem cells begin to differentiate, telomerase activity drops and their telomeres begin to shorten.

Teratoma(from the Greek. teratos - freak) - a benign tumor caused by a violation of embryonic development. As a rule, it consists of muscle, nervous and other tissues.

Totipotency- the ability to create a whole organism, the repetition of embryogenesis from a single cell.

fibroblasts(from lat. fibra - fiber and blastуs - sprout) - the main cellular form of the connective tissue of animals and humans. Fibroblasts form the fibers and ground substance of this tissue. When the skin is injured, they are involved in the closure of wounds and the formation of scars.

ectoderm- outer germ layer of multicellular animals. From the ectoderm, the skin epithelium, the nervous system, the sense organs, the anterior and posterior sections of the intestine, etc. are formed.

Endoderm- internal germ layer of multicellular animals. From the endoderm, the intestinal epithelium and associated glands are formed: pancreas, liver, lungs, etc.

Today, probably everyone has heard about stem cells. But there are so many speculations and rumors around this topic that it is very difficult to separate the truth from the fiction. Let's try to figure out how stem cells can help us and why we need to save them.

What are stem cells?

Stem cells are the precursor cells from which all human organs and tissues are formed. When conception occurs, during the first month a living lump - an embryo - consists only of stem cells. They are the strongest, but they cannot be used - such a ban has been imposed by the governments of all countries of the world.

Stem cells are found in small amounts in human bone marrow and adipose tissue. Moreover, with age, their number decreases, and the quality deteriorates. Scientists have learned how to isolate such cells from the bone marrow and use them to treat diseases. But the optimal source of stem cells is the blood found in the placenta and umbilical cord of the newborn. It is in it that the concentration of stem cells is maximum.

How are stem cells obtained?

Stem cells can be isolated from the human bone marrow and their number can be increased - cultured. And you can get them from cord blood or umbilical cord, and this possibility is available only at the time of the birth of the child.

How does this happen? As soon as the baby is born and separated from the umbilical cord, the doctor who takes delivery inserts a needle into the umbilical vein, and from there, by gravity, 50 to 250 ml of blood comes out into a bag with a special substance against blood clotting, which consists of 3-5% of powerful and strong stem cells. After the placenta has passed, the midwife cuts off 10-20 cm of the umbilical cord and places it in a special package, which is delivered to the stem cell bank laboratory.

As you can see, the procedure for collecting cord blood and umbilical cord stem cells is completely painless and absolutely safe for both mother and baby. It can be performed both in natural childbirth and in caesarean section.

Then within 4-6 hours the biomaterials are delivered to the laboratory. Here they are processed, frozen and stored. Cord blood or umbilical cord stem cells, frozen under certain conditions, can be stored at extremely low temperatures for decades.

Why save stem cells?

Today, medicine can do a lot, but there are diseases in front of which traditional methods of treatment are powerless. This is where stem cells can help. In many cases, they contribute to the restoration of blood, bone marrow, tissue regeneration after wounds and burns. And for diseases of the immune system and blood, stem cell transplantation is the only radical method of therapy.

One of the problems of this method is the selection of stem cells suitable for a particular patient. With nominal storage, all harvested cord blood stem cells will be native to your child and will be ideal for him. And stem cells from the umbilical cord can be used to treat the whole family.

What diseases can stem cells help with?

To date, stem cells have been used for decades all over the world in the complex therapy of oncological diseases of the blood, immunodeficiencies of various etiologies.

The use of stem cells has shown positive results in the treatment of strokes, heart attacks, type 1 diabetes and cartilage growth.

The list includes more than 80 diseases. The most severe and common include:

• blood diseases (leukemia) and malignant tumors;
• diabetes;
• heart disease;
• stroke and brain damage;
• muscular dystrophy;
• Parkinson's disease;
• Alzheimer's disease;
• multiple sclerosis;
• spinal injuries;
• amyotrophic lateral sclerosis;
• systemic lupus erythematosus;
• autoimmune diseases;
• cerebral palsy;
• chronic hepatitis and cirrhosis of the liver.

What do stem cell banks do?

Stem cell banks process and store samples containing stem cells. Storage of stem cells can be public and nominal. Samples from the public registry can be used by anyone who needs stem cells. In nominal storage, stem cells are disposed of by their owners. Thus, stem cells isolated from the blood of the umbilical cord or umbilical cord belong to the child's parents. But in this case, they pay for the services of their collection, processing and storage.

What to consider when choosing a stem cell bank:

✓ How many years has the bank been in existence?

The older the bank is, the greater the guarantee of stability you get, the more experience the bank employees have in isolating, harvesting and storing stem cells.

✓ Is the bank licensed?

The bank must have a license for the collection, transportation and storage of stem cells issued by the health committee.

✓ On the basis of which institution is the bank located?

The advantage for the bank is its location on the basis of a medical institution or research institute. Firstly, because in hospitals there is an autonomous power supply system. Secondly, the conditions necessary for working with biological material have already been created here.

The bank, like any medical institution, must have round-the-clock security, because the bank contains precious stem cell samples, a lot of unique medical equipment and a database.

✓ What equipment does its laboratory and store have?

To date, there are 3 devices on which stem cells can be isolated: double centrifuge (semi-automated device), Sepax (Switzerland) and Macopress (France) devices.

The presence of these devices is mandatory for the successful operation of the bank.

✓ Does the bank have a system for automatic control of cryostorages?

The bank's cryo-storage should be equipped with an IT-monitoring system for cryodewars, in which stem cell samples are stored. At any time, bank employees can check the temperature of the sample storage and the filling of the cryo dewar. And also get a report on the storage of the sample for any period of time and save it on the server for the archive.

✓ Does the bank have its own courier service?

In order to promptly collect cord blood from the maternity hospital and extract the stem cell sample as soon as possible without losing their viability, the bank must have a courier service, whose employees can take a blood sample from the maternity hospital and deliver it to the bank at any time.

✓ Does the bank conduct research in the field of cellular technologies?

It is very important that scientific work be organized on the basis of the bank, as well as cooperation with leading research institutes and medical institutions of the city.

✓ Does this bank have experience with successful use of cord blood stem cells?

It would not be superfluous to ask the tank for statistics on the demand for samples and experience in using stem cells to treat patients with various diseases.

Stem cells are undifferentiated cells that are present in the human body as a "strategic reserve" at any stage of its life. A feature is their unlimited ability to divide and the ability to give rise to any kind of specialized human cells.

Due to their presence, there is a gradual cellular renewal of all organs and tissues of the body and the restoration of organs and tissues after damage.

History of discovery and research

The Russian scientist Alexander Anisimov was the first to prove the existence of stem cells. It happened back in 1909. Their practical application interested scientists much later, around 1950. And only in 1970, for the first time, stem cells were transplanted into patients with leukemia, and this method of treatment began to be used all over the world.

From about that time, the study of stem cells was singled out as a separate direction, separate laboratories and even entire research institutes began to appear, developing methods of treatment using progenitor cells. In 2003, the first Russian biotechnology company called the Human Stem Cell Institute appeared, which today is the largest repository of stem cell samples, and also promotes its own innovative drugs and high-tech services on the market.

At this stage in the development of medicine, scientists have managed to obtain an egg from a stem cell, which in the future will allow infertile couples to have their own children.

Video: Successful biotechnology

Where are progenitor cells located?

Stem cells can be found in almost every part of the human body. They are necessarily present in any of the tissues of the body. Their maximum amount in an adult is contained in the red bone marrow, slightly less in peripheral blood, adipose tissue, and skin.

The younger an organism is, the more it contains, the more active these cells are in terms of the rate of division, and the wider the range of specialized cells that each progenitor cell can give birth to.

Where do they get the material

• Embryonic.

The most “tasty” for researchers are embryonic stem cells, since the less the organism has lived, the more plastic and biologically active precursor cells are.

But if it is not a problem for researchers to obtain animal cells, then any experiments using human embryos are recognized as unethical.

This is despite the fact that, according to statistics, approximately every second pregnancy in the modern world ends in an abortion.

• From cord blood.

Available in terms of morality and legislative decisions in a number of countries are cord blood stem cells, the umbilical cord itself and the placenta.

Entire banks of cord blood stem cells are currently being created, which can later be used to treat a range of diseases and consequences of bodily injuries. On a commercial basis, numerous private banks offer parents a nominal “deposit” for their child. One of the arguments against collecting and freezing cord blood is the limited amount that can be obtained in this way.

It is believed that only a child up to a certain age and body weight (up to 50 kg) will be enough to restore hematopoiesis after chemotherapy or radiotherapy of their own defrosted stem cells.

But it is not always necessary to restore such a large amount of tissue. To restore, for example, the same cartilage of the knee joint, only a small part of the saved cells will be enough.

The same applies to the restoration of cells of the damaged pancreas or liver. And since stem cells from one portion of umbilical cord blood are divided into several cryotubes before freezing, it will always be possible to use a small part of the material.

• Obtaining stem cells from an adult.

Not everyone was lucky enough to receive their "emergency supply" of stem cells from umbilical cord blood from their parents. Therefore, at this stage, methods are being developed to obtain them from adults.

The main tissues that can serve as sources are:

• adipose tissue (taken during liposuction, for example);
• peripheral blood, which can be taken from a vein);
• red bone marrow.

Adult stem cells obtained from different sources may have some differences due to the loss of cell versatility. For example, blood and red bone marrow cells can give rise predominantly to blood cells. They are called hematopoietic.

And stem cells from adipose tissue are much easier to differentiate (reborn) into specialized cells of organs and tissues of the body (cartilage, bones, muscles, etc.). They are called mesenchymal.

Depending on the scale of the task that scientists face, they may need a different number of such cells. For example, methods are now being developed to grow urine-derived teeth from them. There are not so many of them there.

But given the fact that a tooth needs to be grown only once, and its service life is significant, then little stem cells are needed for it.

Video: Pokrovsky Stem Cell Bank

Banks for storage of biological material

Special banks are created for storage of samples. Depending on the purpose of storing the material, they may be state-owned. They are also called registrar banks. Registrars store stem cells from unnamed donors and may, at their discretion, provide the material to any medical or research institution.

There are also commercial banks that earn money by storing samples from specific donors. Only their owners can use them to treat themselves or close relatives.

If we talk about the demand for samples, then the statistics are as follows:

• every thousandth sample is in demand in registrar banks;
• material stored in private banks is even less frequently used.

However, it makes sense to keep a nominal sample in a private bank. There are several reasons for this:

• donor samples cost money, sometimes a lot, and the amount required to buy a sample and ship it to the right clinic is often many times the cost of storing your own sample for several decades;
• a nominal sample can be used to treat blood relatives;
• it can be assumed that in the future, organs and tissues will be restored using stem cells much more often than it happens in our time, and therefore the demand for them will only grow.

Application in medicine

In fact, the only direction of their use that has already been studied is bone marrow transplantation as a stage in the treatment of leukemia and lymphomas. Some studies on the reconstruction of organs and tissues with the help of stem cells have already reached the stage of experiments on humans, but there is no talk of mass introduction into the practice of doctors yet.

To obtain new tissues from stem cells, it is usually necessary to perform the following manipulations:

• collection of material;
• isolation of stem cells;
• growing stem cells on nutrient substrates;
• creation of conditions for the transformation of stem cells into specialized ones;
• reducing the risks associated with the possibility of malignant transformation of cells derived from stem cells;
• transplantation.

Stem cells are isolated from tissues taken for the experiment using special devices called separators. There are also various methods of stem cell sedimentation, but their effectiveness is largely determined by the qualifications and experience of the staff, and there is also a risk of bacterial or fungal contamination of the sample.

The resulting stem cells are placed in a specially prepared medium that contains the lymph or blood serum of newborn calves. On a nutrient substrate, they divide many times, their number increases several thousand times. Before being introduced into the body, scientists direct their differentiation in a certain direction, for example, they receive nerve cells, liver or pancreas cells, a cartilaginous plate, etc.

It is at this stage that there is a danger of their degeneration into tumor. To prevent this, special techniques are being developed that reduce the likelihood of cancerous degeneration of cells.

Methods for introducing cells into the body:

• introduction of cells into tissues directly in the place where there was an injury or tissues were damaged as a result of a pathological process (disease): introduction of stem cells into the area of ​​hemorrhage in the brain or into the site of damage to peripheral nerves;
• introduction of cells into the bloodstream: this is how stem cells are injected in the treatment of leukemia.

Pros and Cons of Using Stem Cells for Rejuvenation

The study and use in the media is increasingly being cited as a way to achieve immortality, or at least longevity. Already in the distant 70s, stem cells were administered as a rejuvenating agent to elderly members of the Politburo of the CPSU.

Now that a number of private biotechnology research centers have emerged, some researchers have begun to conduct rejuvenating injections of stem cells previously taken from the patient himself.

Such a procedure is quite expensive, but no one can guarantee its result. When agreeing, the client must be aware that he is participating in an experiment, since many aspects of their use have not yet been studied.

Video: What Stem Cells Can Do

The most common types of procedures are:

• the introduction of stem cells into the dermis (the procedure is somewhat reminiscent of biorevitalization);
• filling in skin defects, adding volume to tissues (this is more like using fillers).

In the second case, the patient's own adipose tissue and his stem cells are used, mixed with stabilized hyaluronic acid. Animal experiments have shown that such a cocktail allows a larger amount of adipose tissue to take root and maintain volume for a long time.

The first experiments were carried out on people who were removed wrinkles according to this method and had an increase in the mammary glands. However, there is still not enough data for any doctor to repeat this experience on his patient, providing him with a guaranteed result.

To renew the cellular composition of a damaged organ without surgical intervention, to solve the most complex tasks that were previously only possible with organ transplantation - these tasks are being solved today with the help of stem cells.

For patients, this is a chance to get a new life. The important thing here is that the technology of using stem cells is available for almost every patient and gives a truly amazing result, expanding the possibilities of transplantation.

Stem cells are able to transform, depending on the environment, into tissue cells of various organs. One stem cell produces many active, functional offspring.

Research on genetic modification of stem cells is carried out all over the world, methods of their growth are being intensively studied.

There are many diseases that are practically not treated or their treatment is not effective with medication. It is these diseases that have become the object of the closest attention of researchers.

Stem cells, regeneration, tissue repair. From Adam to the atom

What is stem cells?

When an egg is fertilized, one zygote (fertilized cell) divides and gives rise to cells whose main task is to transfer genetic information to the next generations of cells.

These cells do not yet have their own specialization, the mechanisms of such specialization have not yet been turned on, and that is why such embryonic stem cells make it possible to use them to create any organs.

We all have stem cells. They were originally found in the tissues of the bone marrow. The easiest way to detect and isolate stem cells is in young people, children. But older people also have them, though in much smaller quantities.

Compare: a person aged 60-70 years has only one stem cell for five to eight million cells, and an embryo has one stem cell for ten thousand.

Possibilities of adult stem cells - Sergey Kiselev

What is the secret of stem cells?

The secret of stem cells is that, being immature cells themselves, they can transform into a cell of any organ.

As soon as the stem cells of the body receive a signal about damage to tissues, any organs, they are sent to the lesion. There they turn into precisely those cells of human tissues or organs that need protection.

Stem cells can transform and become any cell: hepatic, nervous, smooth muscle, mucous. Such stimulation of the body leads to the fact that he himself begins to actively regenerate his own tissues and organs.

An adult person has a very small supply of stem cells. Therefore, the older a person is, the more difficult and with greater complications is the process of regeneration and restoration of the body after injuries or during illness. Especially if the damage to the body is extensive.

The body cannot regenerate lost stem cells on its own. Developments in the field of modern medicine today make it possible to introduce stem cells into the body and, most importantly, direct them in the right direction. Thus, for the first time, it becomes possible to treat such dangerous diseases as cirrhosis, diabetes, and stroke.

Garyaev, Petr Petrovich - How to manage stem cells

Sources of stem cells

The main source of stem cells in the body is the bone marrow. Some, but very small, their amount is found in other human tissues and organs, in peripheral blood. Many stem cells contain blood from the umbilical vein of newborns.

Cord blood as a source of stem cells has a number of undeniable advantages.

First of all, it is much easier and painless to collect it than peripheral blood. Such blood gives genetically ideal stem cells in case of need for its use by close relatives - mother and child, brothers and sisters.

During transplantation, the immune system, newly created from donor stem cells, begins to fight the patient's immune system. It is very dangerous for the life of the patient. The condition of a person in such cases is extremely difficult, up to death. The use of cord blood in transplantation significantly reduces such complications.

In addition, there are a number of undoubted advantages of using cord blood.

1. This is the infectious safety of the recipient. Infectious diseases (cytomegalovirus and others) are not transmitted from the donor through the umbilical cord blood.
2. If it was collected at the time of a person's birth, then he can use it at any time to restore health.
3. The use of blood from the umbilical vein of newborns does not raise ethical problems, as it is then disposed of.

Stem cell applications

Stem cells were first used to treat anemia in 1988 in France.

Highly effective stem cell treatment of tumors, strokes, heart attacks, injuries, burns, has forced the creation of special institutions (banks) in developed countries to store frozen stem cells for a long time.

It is already possible today, by order of relatives, to place the umbilical cord blood of a child in such a commercial nominal blood bank, so that in case of injury, illness, it would be possible to use one's own stem cells.

Transplantation of internal organs restores human health only if it is carried out in a timely manner, and the organ is not rejected by the patient's immune system.

Approximately 75% of patients in need of an organ transplant die during the waiting period. Stem cells can be an ideal source of "spare parts" for humans.

Even today, the spectrum of stem cell application in the treatment of the most severe diseases is very wide.

Recovery of nerve cells allows you to restore capillary circulation and cause the growth of the capillary network at the site of injury. To treat a damaged spinal cord, they use the introduction of neural stem cells, or pure cultures, which will then turn into nerve cells on the spot.

Some forms of leukemia in children have become curable thanks to advances in biomedicine. Hematopoietic stem cell transplantation is used in modern hematology, and bone marrow stem cell transplantation is used in a wide clinic.

Exceptionally difficult to treat systemic diseases caused by dysfunction of the immune system: arthritis, multiple sclerosis, lupus erythematosus, Crohn's disease. Hematopoietic stem cells are also applicable in the treatment of these diseases

There is practical clinical experience in the use of neural stem cells in the treatment of Parkinson's disease. The results are beyond all expectations.

Mesinchymal (stromal) stem cells have already been used in the orthopedic clinic for the past few years. With their help, they restore destroyed articular cartilage, bone defects after fractures.

In addition, these same cells have been used for the last two or three years by direct injection in the clinic for the restoration of the heart muscle after a heart attack.

The list of diseases that can be treated with stem cells is growing every day. And it gives hope for life to terminally ill patients.

List of diseases treated with stem cells

Benign diseases:

• adrenoleukodystrophy;
• Fanconi anemia;
• osteoporosis;
• Gunther's disease;
• Harler's syndrome;
• thalassemia;
• idiopathic aplastic anemia;
• multiple sclerosis;
• Lesh-Nihan syndrome;
• amegakaryocytic thrombocytopenia;
• Kostman's syndrome;
• lupus;
• resistant juvenile arthritis;
• immunodeficiency states;
• Crohn's disease;
• Bar's syndrome;
• collagenoses.

Malignant diseases:

• non-Hodgkin's lymphoma;
• myelodysplastic syndrome;
• leukemia;
• breast cancer;
• neuroblastoma.

Miracles of medical and aesthetic cosmetology

The desire of a person to look young, fit for decades is due to the modern pace of life. Is it possible to look as good at fifty as at forty?

Medical cosmetics, with the use of modern biotechnology, provides such an opportunity. Today it is possible to significantly improve turgor, skin elasticity, save a person from eczema and dermatitis.

Stem cells, which are injected during mesotherapy, eliminate skin pigmentation, scars, the effects of exposure to chemicals, laser. Wrinkles, spots after acne disappear, skin tone improves.

In addition, with the help of mesotherapy, problems of hair and nails are solved. They acquire a healthy appearance, their growth is restored.

However, when using highly effective cosmetic preparations, one should beware of scammers advertising preparations that allegedly contain stem cells.

The cost of stem cell treatment

Stem cell treatment is carried out in many countries, including Russia. Here it ranges from 240,000 to 350,000 rubles.

The high price is justified by the high-tech process of growing stem cells.

In medical centers, for such a cost, one hundred million cells are injected into the patient per course. If a person is more than mature, it is possible to introduce such an amount in one procedure.

The cost of procedures, as a rule, does not include manipulations to obtain stem cells. With the introduction of stem cells during surgery, you will have to pay separately for this type of medical service.

Mesotherapy is more accessible today. For those who want to get a pronounced cosmetic effect, the approximate cost of one procedure in Russia will cost from 15,000 to 30,000 rubles. In total, they need to be done from five to ten for the course.

Forewarned is forearmed

Realizing the brilliant future of the application of new medical technologies, however, I would like to warn against excessive optimism and recall the following:

1. Stem cells are an unusual drug that is difficult to reverse. The fact is that stem cells, unlike other drugs, are not removed from it in the same way as conventional drugs. They contain living cells and their behavior is not always predictable. In case of harm to the patient's body, it is impossible for doctors to stop the process;
2. Medical scientists hope that the side effects of stem cell treatment will be minimal. But it cannot even be assumed that there will be no side effect in the treatment. Like any drug, even aspirin, stem cells have limitations and side effects in their use;
3. Clinical trials in leading medical centers have only confirmed that bone marrow transplantation is the only method of cell therapy so far;
4. The use of stem cells is not a panacea for the treatment of absolutely all diseases, although they do have great potential in the treatment of many injuries, burns, injuries and diseases;
5. Even if many famous people, athletes, politicians use stem cell therapy, this does not mean that this treatment method is suitable for everyone. Practitioners must be trusted.

Is immortality possible?

Human immortality is possible – we are convinced by the achievements of modern medicine.

Fantastic ideas about the synthesis of human organs are already turning into a reality in the near future. Ten years will pass and artificial kidneys, heart, liver will become available to every person. Simple injections will restore the skin, rejuvenate. The main merit in this will belong to stem cells.