How is a bone marrow transplant performed? How is a bone marrow transplant done? What are the risks of bone marrow transplantation for the donor and the patient? Are there risks and side effects?

Bone marrow is an organ of the circulatory system that performs the function of hematopoiesis (blood formation). Many diseases associated with disruption of the blood renewal process occur in various categories of the population. This means that there is a need for stem cell transplantation.

Such an operation requires a person whose genetic material is suitable for the recipient. Bone marrow donation scares many people, as people simply do not know about the possible consequences of the transplant.

Transfer options

Bone marrow transplantation is indispensable for diseases associated with dysfunction of this organ or the immune system.

Usually transplantation is needed for malignant blood diseases:

Stem cell transplantation is also necessary for non-malignant diseases:

• Severe metabolic diseases: Hunter syndrome (a disease linked to the X chromosome, characterized by the accumulation of fats and protein-carbohydrates in cells), adrenoleukodystrophy (characterized by the accumulation of fatty acids in cells);
• Immunity deficiencies: HIV infection (acquired disease), severe immunodeficiency (congenital);
• Bone marrow diseases: Fanconi anemia (fragility of chromosomes), aplastic anemia (inhibition of the hematopoietic process);
• Autoimmune diseases: lupus erythematosus (inflammation of connective tissue, characterized by damage to the tissue itself and the vessels of the microvasculature), rheumatoid arthritis (connective tissue and small vessels of the periphery are affected).

In medical practice, these diseases are treated with radiation. But such methods kill not only tumor cells, but also healthy ones.

Therefore, after intensive chemotherapy, damaged or destroyed hematopoietic cells are replaced with healthy ones during transplantation.

This treatment method does not guarantee 100% recovery, but can prolong the patient’s life.

Watch the video about bone marrow transplantation:

Selection of cells

Material for cell transplantation can be obtained:

1. From someone in need, his illness may be in remission for a long period of time (unexpressed symptoms and acceptable tests). This type of transplant is called autologous.
2. From an identical twin. This type of transplant is called syngeneic.
3. From a relative(not all relatives may be suitable based on genetic material). Usually brothers or sisters are suitable, compatibility with parents is much less. The chance that a sibling will match is approximately 25%. This type of transplant is called an allogeneic related donor transplant.
4. From an unrelated person(if relatives are not suitable for the person in need, then national or foreign cell donation banks come to the rescue). This transplant is called an allogeneic foreign donor transplant.

Any person whose age falls within the category of 18-50 years can be a stem cell donor. not sick:

• autoimmune diseases;
• severe infectious diseases;
• hepatitis B and C;
• tuberculosis;
• acquired or congenital immunodeficiency;
• oncology;
• severe mental disorders.

To become a donor, you need to go to the hospital. They will tell you where the nearest one is located. donor registry center. Experts will tell you how cells are taken from a donor, how the operation itself occurs, and what the consequences may be.

In a specialized department of the center you need to donate nine milliliters of blood for undergoing the typing procedure- determining the basics of donor material.

The information is entered into the register (a database where all donor materials are stored). After depositing materials into the donor bank, you must wait until you find person in need of a transplant. The process may drag on for several years, or may never be completed.

Stem cell collection procedure

Hematopoietic cells can be collected from the bone marrow using two methods. One of them is chosen by specialists in accordance with medical indications for a particular donor.

Stem cell collection methods:

1. From the pelvic bone. To carry out the procedure, a preliminary test is taken to determine whether the person can tolerate anesthesia. The day before the operation, the donor is hospitalized. Stem cells are collected under general anesthesia with a large syringe into the area where the bone tissue is concentrated. Usually several punctures are made at once, through which up to two thousand milliliters of liquid, which is several percent of the total bone marrow share. The procedure takes place within 30 minutes, and the full recovery period lasts up to a month.
2. Through the blood of a donor. Seven days before the date of the collection procedure, the donor is prescribed a special drug Leucostim, which causes the release of stem cells into the blood. After at the donor take blood from your hand, and later the stem cells are separated. The rest of the blood with the separated stem cells is returned through the second arm. This procedure takes several hours, and recovery takes about fourteen days.

It is worth remembering that the procedure of stem cell donation is not paid and is performed to save the life of another.

Consequences for the donor

The collection procedure is completely safe if the donor has no medical contraindications. When harvesting through the pelvic bone after surgery possible bone pain.

With the second method, within a week of exposure to the drug There may be unpleasant sensations: pain in muscles and joints, headache, nausea. These consequences are a completely normal reaction of the body to donation.

According to international regulations, the issue of admitting a future donor is decided by doctors not associated with the hospital where the recipient is located. This will further protect the donor.

There are times when complications arise: consequences of anesthesia, infections, anemia and hemorrhages. In this case, Russia provides insurance for hematopoietic cell donors, which means guaranteed treatment in a hospital.

Recovery period

After the donation procedure, the body needs to renew the efforts spent and increase immunity. Folk remedies are used for this:

1. Tea from wild clover(several flowers are brewed in boiling water and drunk);
2. Kalgan(bloodroot). The crushed roots of the plant are poured with 70% medical alcohol and left for seven days. Take a few drops three times a day;
3. They also take general strengthening and boosting immunity drugs: Askofol, Activanad-N.

Thus, each person decides for himself whether to become a donor of bone marrow cells or not, because on the one hand - a noble cause, saving the life of another person, and on the other hand, a complex procedure with, although rare, possible complications.

Bone marrow transplantation is a fairly new procedure that allows you to fight many pathologies that were previously considered incurable. Today, thanks to such a transplant, it is possible, if not saved, to extend the lives of thousands of patients a year.

Such an organ has a liquid structure. It has a hematopoietic function. The bone marrow contains a huge number of pillar cells that have the ability to constantly renew themselves. Thanks to the procedure of implanting the donor's columnar cells, further restoration of the patient's cells is possible.

The transplant procedure should be divided into three main stages:

• Preparing the patient for transplantation;
• Direct transplantation;
• Period of adaptation and recovery.

When it is clear what a bone marrow transplant is, how the operation is performed, it also does not hurt to find out. The procedure takes approximately an hour and is a process similar to an intravenous infusion. The preparation process is considered longer and more difficult, as well as postoperative rehabilitation, during which the engraftment of new cells occurs.

First of all, and this is the most important thing, it is necessary to find a donor suitable in all respects. The columnar cells of a healthy person must be genetically ideal; a lot of research and blood tests are carried out to make sure of this.

Most often, donors are the closest relatives (for example, a brother or sister), and sometimes just strangers who have the most suitable material. Such people are registered in the international donor register. In some cases, the material is taken from the patient himself.

Before the actual transplant is performed, the patient will need to undergo many tests that will reflect the detailed condition. It must fully comply with the parameters that are necessary to perform the operation.

After this, the diseased cells are eliminated. Chemotherapy or radiation therapy may be used for this.

After the last procedures, a catheter is inserted into the vein, through which new cells will be introduced, as well as the necessary medications. It is worth noting that the operation does not require operating room conditions; the transplantation is carried out in a simple ward. Donor cells enter the bloodstream and gradually begin to take root and multiply.

Then comes the most difficult period - adaptation. Its duration can range from 2 to weeks. For successful implementation it is necessary:

• Organization of sterile conditions for the patient;
• Taking special medications that help reduce the risk of donor material rejection;
• Taking antibiotics will help avoid the development of infectious complications.

After the adaptation period, doctors can conclude that the operation was successful.

To understand in more detail what a bone marrow transplant is, you should look video

As already noted, before starting such an operation, you should find a donor that ideally matches the parameters. For a complete picture, you need to not only know what it is How does a bone marrow transplant work? the procedure for the donor also needs to be understood.

The collection of the necessary donor cells is performed under local anesthesia. Punctures are made in a certain area of ​​the pelvic and femur bones, through which material for transplantation is taken along with blood. The volume of such liquid can be from 950 to 2000 ml. The donor's cell count returns to normal within a month. True, pain may be observed at the puncture sites, which resembles the pain after a blow, but they can be easily dealt with by taking anesthetic drugs.

Life after bone marrow transplant and consequences

A procedure such as bone marrow transplantation is quite difficult for a person, both physically, morally and emotionally. And not only for the patient himself, but also for his family.

After the operation, there is a strong feeling of weakness, vomiting, nausea, diarrhea and many other unpleasant consequences.

The most critical period is considered to be up to a month, when the body is weakened and constantly requires blood transfusions, antibiotics and other medications. At this time, a person is prone to various infections and diseases. Doctors are doing everything possible to prevent such consequences.

After the donor's bone marrow engrafts and begins to multiply cells, the patient's condition stabilizes and he is discharged from the hospital.

But that doesn't mean everything is okay now. After discharge, a patient who has undergone a bone marrow transplant must be under constant medical supervision. Even in the future, the body is prone to infection by infectious diseases and the appearance of various complications that require prompt, timely and correct medical care.

In general, a person after a transplant notices an improvement in his condition, but the fear of the return of the disease is very strong, and sometimes develops into excessive panic. In such cases, you cannot do without the help of a psychologist.

Do you understand how a bone marrow transplant works? What are the consequences after a bone marrow transplant for the donor? Leave your opinion or feedback for everyone on the forum.

Upon careful study, it can be seen that bone marrow transplantation is a process that has technical difficulties. If a person wants to be a donor, it is not necessary that he will be one. Due to immune incompatibility reactions, it is difficult to select the optimal material for transplantation into a patient with leukemia or lymphoma.

When planning a bone marrow transplantation, it is necessary not only to select an organ according to the HLA system, but also to study the antigens of other histocompatibility variants. It is impossible to choose the ideal tissue, since there will always be foreign chemicals that will be rejected by the recipient’s body. The task of bone marrow transplantation is to select a material with a minimum amount of incompatible antigens, which will allow control of rejection reactions. Even autotransplantation (transplantation of one's own tissues) is not the best option for lymphomas and leukemia, since stem cells are not cleared of cancerous structures. Re-introduction of oncogenes can provoke an exacerbation or relief of clinical symptoms. The decision is at the doctor’s discretion if there are no alternative options.

How does the transplant take place?

Before transplantation, the recipient undergoes “powerful” chemotherapy and radiation. The goal of the procedure is to destroy the affected formed elements located inside the bone marrow canal. After complete neutralization of infected cells, a transplant of healthy stem cells is required. After engraftment of donor tissues, you can count on optimal hematopoiesis, but you need to control rejection reactions. Regardless of the quality of the bone marrow transplant operation, engraftment is disrupted by immune rejection of foreign tissue.

There are 3 options for taking stem cells from a donor:

1. Brain puncture biopsy through surgery with anesthesia. The most common location is the flat bones of the pelvis;
2. Hematopoietic stem cells are obtained after the administration of drugs aimed at enhancing the release of the rudiments of blood cells from the intraosseous cavity. The collection is carried out from a vein by passing blood through separator filters;
3. When a baby is born, a transplant can be obtained from umbilical cord blood.

The latter option is rarely used due to the impossibility of accurately determining the fetal blood phenotype in advance. Only if it is necessary to introduce a large number of stem cells, the option of using blood from the umbilical cord is ideal.

Bone marrow transplantation (stem cell transplantation) is one of the most effective methods of treating severe cancers that were previously considered incurable. This is a complex medical procedure that requires special training, the use of innovative equipment and careful selection of a donor.

What is bone marrow?

Bone marrow is the same part of the human body as the liver, heart or kidneys, but the correct answer to the question of where this organ is located is “everywhere,” since the products of its activity are blood.

Bone marrow performs several functions, and one of them is the function of hematopoiesis. In its red part, the generation of cells occurs, which are subsequently transformed into blood elements.

In some diseases, the bone marrow is depleted and loses its ability to produce blood cells, and the only way to save the life and health of the patient is bone marrow transplantation (BMT oncology).

You need to understand that TCM is not a replacement for your own bone marrow, but only helps the body restore hematopoietic function.

For what diseases is transplantation performed?

For blood cancer, lymphoma and other oncological diseases, to inhibit the growth of pathological cells, patients undergo chemotherapy or radiation, which have a detrimental effect on the bone marrow.

In this case, patients are also transplanted with donor or own cells to restore hematopoietic function in the body.

How is the operation performed?

The process of bone marrow transplantation is a fairly simple procedure; the preparatory and postoperative stages are much more complicated.

There are two types of transplant surgery - autologous or allogeneic.

1. Autologous is “own” in professional language, that is, stem cells for such an operation are taken directly from the patient
2. An allogeneic transplant involves taking material from a donor who must match the patient genetically. Most often, the donor is a close relative of the patient. The best option is cell transplantation of identical twins, which does not cause a negative reaction in the recipient’s body.

At the first stage of the operation, the patient undergoes chemotherapy and radiation therapy, which should completely destroy the bone marrow. Next, a catheter is inserted into his bloodstream and stem cells are infused.

During the procedure and for some time after it, the patient and his vital functions should be monitored by a doctor.

Engraftment of donor cells takes 21 to 35 days, and complete rehabilitation of the patient can take a year or more. Bone marrow transplantation is considered a relatively safe operation, so it is often performed in children.

Contraindications and complications

The following pathologies are contraindications to bone marrow transplantation:

The main complication that occurs in recipients is the rejection of donor bone marrow by the patient’s immune system, which perceives it as foreign cells. To avoid such consequences, the patient is prescribed antibacterial and immunosuppressive drugs.

The growth of pathological cells in the postoperative period is also possible - this condition is called relapse after transplantation, and requires a second stem cell transplantation.

How long do they live after transplantation?

The prognosis for a patient's survival after surgery depends on several factors, including the primary disease and its course, age and health status, compatibility with the donor, etc.

If the operation is successfully performed and there are no complications, the patient’s life can be counted in decades.

How much does bone marrow and surgery cost?

Bone marrow transplantation is carried out in many countries of Europe and the CIS, including Ukraine, Belarus and Russia - the corresponding medical institutions are located in large cities (St. Petersburg, Moscow, Minsk, Kiev).

The amount that will need to be paid for the operation depends on the country and the specific clinic - for example, the price of BMT in Germany is about 200 thousand euros, and the cost in Israel is about 250 thousand, excluding the patient’s residence and the search for a donor in the international registry (if none of the patient’s close relatives is suitable as a donor).

Russian patients will have to pay about 3 million rubles if the operation is performed in Moscow clinics, and about 2 million in St. Petersburg.

Also in Russia and Belarus there is a quota for free bone marrow transplants - in this case, the procedure is financed by the state or charitable foundations.

Most often, quotas are awarded to children from low-income families whose parents are unable to pay for treatment on their own.

How to become a donor?

Usually the bone marrow that is transplanted into patients is taken from close relatives, but a complete stranger can also become a donor. Stem cell donation is no less common around the world than blood donation.

Any person between 18 and 50 years of age who has not had hepatitis or HIV and is not a carrier of infectious diseases can donate biological material.

Donors for specific patients are selected based on the so-called tissue compatibility - certain proteins on the surface of the cells of the donor and the patient must match.

There is a special international registry that includes millions of potential donors; in addition, such a registry exists in almost every country.

In the context of the financial crisis, many people are interested in the question of how much donors are paid in Russia, because many clinics offer money for seminal fluid and eggs.

It should be noted that bone marrow donation is voluntary, anonymous and free of charge.

Donors are paid for travel to the procedure site, accommodation and food, and are also compensated for financial losses at work.

In other words, it is impossible to sell bone marrow - saving someone else's life can already be considered a sufficient reward.

How is bone marrow harvested?

Bone marrow cells are collected in two ways: from a puncture in the pelvic bone or from peripheral blood.

In the second case, the recipient is injected with a special drug that “expels” the cells into the bloodstream, after which the stem cells are taken from the blood using a special apparatus.

Donating bone marrow is not dangerous. It is not painful and absolutely safe - negative consequences for the donor are extremely rare, and rehabilitation takes about a month.

To become a bone marrow donor, a person must donate blood to determine the phenotype and sign an agreement to join the registry. If someone needs stem cells from a specific donor, they will need to undergo a full examination and donate biological material for transplantation.

The normal functioning of the bone marrow is a constant work of creating new blood cells, which enter the bloodstream to replace those that have aged and died while performing their main tasks of ensuring vital activity and protecting the body. The bone marrow is closely related to the immune system, because it, along with other organs of the immune system, takes an active part in immunopoiesis.

Bone marrow transplantation (BM) often seems to be the last hope for a cure for many patients suffering from diseases of the hematopoietic system that are no longer amenable to other methods of treatment. In addition, bone marrow transplantation can help with congenital and acquired abnormalities of the immune system, as well as with lesions caused by harmful doses of chemicals and radioactive substances for the body.

Interestingly, attempts to transplant a stem cell were made back in the 19th century, however, they could not succeed because it was not open leukocyte systemHLA, characterized by special diversity within itself (polymorphism) and ensuring the immunological compatibility of the donor and recipient (the first antigen of this system was discovered only in 1954 of the last century).

The leading role in transplantology belongs to the major histocompatibility complex located on a small section of the sixth chromosome, which includes loci of the above-mentioned system (HLA) and many loci of other systems. The main task of the major histocompatibility complex genes is to control the synthesis of tissue antigens.

Gives a chance to live

An in-depth clinical study of the major histocompatibility complex, in general, and the HLA system, in particular, united the efforts of many specialists in the field of hematology, immunology, biochemistry and made it possible to consider bone marrow transplantation as one of the most important methods of treating many malignant blood diseases that were previously were considered incurable. At the same time, the correct determination of indications is recognized as the main condition for successful tissue transplantation of active (red) bone marrow (hematopoietic tissue), capable of restoring normal hematopoiesis in the body of the patient (recipient).

However, the greatest effect from bone marrow transplantation can be expected if there is inhibition of hematopoiesis due to the inferiority of the stem cell, rather than from the BM microenvironment. Bone marrow can save a patient’s life in cases of congenital and acquired pathological conditions of the hematopoietic and lymphoid systems, which include:

• Aplastic anemia;
• (acute and chronic);
• Serious immunodeficiency diseases inherited, where primary mixed severe immunodeficiency is an absolute indication for surgery;
• Storage diseases;
• Fanconi anemia;
• Thalassemia major;
• Malignant childhood osteoporosis;
• Malignant;
• Solid neoplastic processes localized outside the bone marrow.

The first place among pathological conditions requiring correction of hematopoiesis with donor bone marrow is shared by leukemia and aplastic anemia. Moreover, in case of leukemia, donor bone marrow will not only replace the diseased organ and begin to work in its place, but will also take on the role of an immunostimulant, capable of giving an adequate immune response to tumor antigens of the leukemia cell.

In aplastic anemia, the main goal of hematopoietic tissue transplantation is aimed at restoring the functional abilities of one's own BM. This category of patients has every chance of recovery provided they receive a compatible transplant according to the antigenic determinants of the main complex.

In the case of immunodeficiency syndromes, a very important factor is identifying the root cause of the disease: it may be a disorder of the functional abilities of the lymphoid system or the inferiority of the stem cell that gives life to all elements of the blood.

It should be emphasized that more than 50% of patients who need a transplant of donor hematopoietic tissue are children, because, as is known, the disease, which is colloquially called “blood cancer,” is young. The peculiarities of transplantation in children lie in the doses of drugs, (often) their names and, in other cases, the use of other equipment (not everything is suitable for children, so the cost of treatment may increase). All stages of bone marrow transplantation, including preparation, in children occur in the same sequence as in adults, so there is little point in dwelling on these issues separately.

New treatment - new difficulties

However, not all so simple. As it turned out, final success depends on many factors, that is, the new, most progressive and effective method of treating hematological pathology has brought new problems, among which are:

1. Secondary disease that develops during transplantation of BM that is HLA compatible, but incompatible with other loci of the main complex (exposure to “minor” transplantation antigens);
2. Infectious complications that develop during the use of immunosuppressive therapy, which must be carried out before and after surgery;
3. The possibility of transplant rejection as a result of undesirable reactions (the new host’s body does not want to accept foreign cells or foreign bone marrow for some reason does not take root in the new place).

In addition, despite the constant increase in BM transplantations, doctors Patients and their relatives constantly face other problems:

• Finding a suitable donor is extremely difficult, because only identical twins are known to be identical;
• Preparation for transplantation requires special equipment and considerable financial costs;
• This operation and subsequent observation may simply not be affordable for the patient’s family if among the relatives there is no person matching the HLA phenotype (first and second class typing).

It should be noted that transplantation of tissue capable of giving life to new full-fledged cells involves not only bone marrow transplantation. In addition, peripheral blood stem cells (PBSC) are transplanted and umbilical cord blood is transfused, which in itself is already a storehouse of stem cells.

Depending on the place where the material was obtained, they talk about transplantation autologous(the patient is transplanted with his own hematopoietic tissue prepared in advance) and allogeneic, referring to donor bone marrow.

autologous bone graft

For example, lymphoma that begins in the lymph nodes can spread to the bone marrow as it progresses. To prevent this from happening, healthy tissue is taken from the patient and sent for storage, and then transplanted into the patient himself. Such a transplantation makes it possible to expand the range of chemotherapeutic measures in the future, since it reduces immunological reactions between the host and the transplant (its own tissue) to zero.

Patients whose hematopoietic organ has practically ceased to function normally and is no longer able to resume its function require an allogeneic transplant. Such people have their last hope in relatives or in those who voluntarily sacrifice their hematopoietic tissue to save another person.

Noble Mission

Some potential donors are shocked by the very name of the future operation. They believe that by giving away such precious material, they themselves will certainly suffer. This happens because many people do not know the principles of BM collection, and they “picture” the consequences of the procedure in their imagination. However there is nothing terrible for the body giving off the CM, the excursion does not entail any serious consequences, except for the complexity of the procedure and pain when collecting material.

Every healthy person from 18 to 55 years of age, whose blood has never been exposed to hepatitis B and C viruses, HIV infection and the causative agent of tuberculosis, who does not suffer from mental disorders and does not have malignant oncological pathology. At the same time, the person donating his bone marrow must understand the dangers for the recipient of concealing the listed diseases, therefore, most often, the antigenic characteristics of blood cells are studied by career donors who regularly undergo medical examinations.

Video: information for bone marrow donors

How and where do they look for a donor?

The first in line for typing for possible bone marrow extrusion for the purpose of transplantation are the patient's close relatives. Due to the fact that a person receives (this happens at conception) half the set of genes that control the synthesis of tissue antigens (haplotype) from each of the parents, the likelihood of matching their HLA phenotype is not so high.

The ideal option is monozygotic (identical) twins, and a good option is siblings, who, according to the laws of genetics, are antigenically compatible with the phenotype of the recipient relative in 1 out of 4 cases. Otherwise, a search begins among compatriots of the same nationality, of whom there are very few, and therefore the chances of finding a suitable donor are low, or an application is made to the international registry if the necessary funds are available for the upcoming operation.

Successful bone marrow transplantation can be carried out provided there is a high degree of antigenic compatibility between the donor and recipient, and here it is necessary to attach particular importance to individual factors.

Leukocyte HLA system

localization of HLA genes on chromosome 6

A special role in transplantation belongs to the leukocyte system (HLA), where tissue antigens are presented in all their diversity on blood cells - leukocytes (T- and B-lymphocytes). It is the HLA system that determines how the new host will accept foreign cells, what the duration of engraftment will be, and how the transplanted tissue will react to the new “place of residence” (if it does not like it, a “graft versus host” reaction will follow).

Considering the polymorphism of the HLA system, one cannot particularly hope that a donor identical in phenotype to a particular patient will be found quickly; it can be found among 30-40 thousand people. However, if we do not take into account “strong” antigens and cross-reacting ones, then the donor can be found among 3 thousand typed individuals, and if we also raise the question of choosing not an identical, but a compatible donor, then he can be found among 130 examined people. True, when transplanting a relatively compatible CM, the main bet will have to be placed on immunosuppressive therapy after surgery, which helps suppress unwanted reactions. In connection with the above, it is better to look for a donor among fellow tribesmen, because Asian, African, and American phenotypes in terms of antigen set can differ significantly from European ones.

Other "influential" moments

Survival after transplantation is somewhat influenced by other antigenic systems, in particular AB0 and Rhesus, therefore, in the case of a positive decision on the possible transplantation of BM from a specific donor to a specific recipient, individual tests for full compatibility. Incompatibility for these antigens in the presence of antibodies against A(II) or B(III) in the patient (“major incompatibility”) or donor (“minor incompatibility”) can result in hemolysis or graft-versus-host disease.

In the context of impending bone marrow transplantation, the female gender and patients who receive frequent blood transfusions during treatment cannot be ignored. Women can be sensitized by previous pregnancies, childbirth and blood transfusions, and men have enough blood transfusions, so this group of patients is approached especially carefully and, having discovered antibodies (and in fact contraindications), are in no hurry to transplant BM, otherwise the phenomenon of secondary replantation and transplantation will develop is rejected “with terrible force” (super acutely).

It should be emphasized that immune reactions, which are the main problem in transplantology, in the most severe form are typical for bone marrow transplantation, because here it is necessary to keep in mind not only the degree of sensitivity of the recipient to specific proteins of the obtained foreign tissue, but also the reaction of the tissue itself to the antigenic set of the new host.

Donor found!

And after much work and ordeal (this is usually what happens when searching for a donor), a person matching the HLA antigens was found. He consents to bone marrow extrusion and can no longer change his mind, since they begin to actively prepare the patient for the upcoming transplant (they “kill” the patient’s bone marrow and immunity and place him in a sterile room while waiting). Now the patient’s life depends entirely on the donor, and if the latter refuses to undergo BM excision, the patient will face certain death.

The donor, who has agreed to donate part of his hematopoietic tissue, is admitted to the hospital for one day, where, under general anesthesia, precious material is obtained in an amount of ≈ 1 liter (by numerous punctures of the ilium). If bone marrow tissue is taken from the patient himself, that is, an autologous transplantation is planned, the material is frozen.

After the procedure, the donor is not in danger of anything bad, however, in the places where the bones are punctured, he may feel pain, which, however, can be easily dealt with with the help of painkillers. There is no need to grieve too much about the lost volume of CM: in a healthy person it recovers within two weeks.

Preparation for a peripheral blood stem cell transplant is somewhat different in terms of its removal. Before the procedure, the person who is going to give the DBS helps it move into the blood vessels and for this purpose takes special drugs called growth factors(sargramostim, filgrastim, etc.). SBCC is collected within 5 hours using the apheresis.

An apheresis system (special equipment) divides the blood into parts, takes stem cells, and returns the remaining blood elements back into the donor’s bloodstream. The productivity of the device is ≈ 40 ml per hour, and thus in 5 hours the donor gives about 200 ml of cells that can save a life.

Apheresis can be called an absolutely safe procedure, even if it is performed on children under one year of age. Yes, yes, no need to be surprised - a child who is six months old can become a donor, he is healthy and matches his phenotype (class 1 and 2 of the HLA system) to a sick brother or sister. Typically, bone marrow or stem cells are collected from the baby when he or she is 9 months old, unless there is an emergency and the material is needed sooner. Unfortunately, statistics indicate that siblings in half of the cases (50%) are semi-identical, 25% match the antigens of the main locus, and the remaining 25% look like strangers in terms of HLA phenotype.

stem cell transplant process

By the way, bone marrow can be transplanted from a person who is over 55 (up to 60 years old), but provided that the hematopoietic tissue has not lost its functional abilities.

Before a bone marrow transplant, an in-depth examination of the patient is performed to study the functional abilities of his organs and systems (the better they work, the higher the likelihood of a successful transplant).

The preparation period is under the constant supervision of high-class doctors. At the same time, during this period, immunological preparation of the transplant is carried out, which is aimed at achieving the following goals:

• Minimize the antigenic activity of the tissue structures of the transplanted tissue;
• Suppress the functional activity of immunocompetent cells of the transplant that are capable of developing a reaction against the tissues of the new host.

The difficulties of immunological preparation of BM are that it should not disrupt the hematopoietic and other functional abilities of the transplanted tissue.

preparing a patient for a bone marrow transplant

In order for the transplant to quickly adapt and take root, it must find itself in comfortable conditions, which the recipient’s body must provide. For this purpose, the patient undergoes a procedure such as conditioning which involves the use of aggressive chemotherapy drugs, destroying bone marrow of the patient and weakening his immune activity. This procedure increases the degree of engraftment of foreign tissue, because in the future it is this tissue that will take on the tasks of life support for the patient’s body, which the patient’s own bone marrow can no longer cope with.

The stage of preparation for transplantation takes place for the patient with restriction of any contacts, in conditions as close as possible to sterile (room, food, linen, etc.). In this condition, the patient is completely defenseless (his own hematopoietic system does not work, immunity is practically absent), so it is no longer possible to leave him without a transplant for a long time.

Transplantation of bone marrow, BMSCs or fetal hematopoietic tissue is carried out in the same sterile box. The operation occurs like a regular blood transfusion.(introduction of a liquid medium into a patient’s vein) and in no way resembles other surgical interventions.

After receiving donor tissue, a new, no less difficult stage begins. Success will depend on how both the transplant and the recipient's body behave.

Life after bone marrow transplant

Engraftment of genetically foreign tissue into a new organism is a long process (up to 2 months) and unpredictable. Life after a bone marrow transplant during the first weeks is another test for the patient, which takes place against the background of constant anxiety and physical weakness. Nausea, diarrhea, and fatigue do not add to optimism. Psycho-emotional stress is also intensified by the fact that only medical staff who, on duty, visit the sterile box can cheer up the patient; other contacts are prohibited.

At this stage, the patient is prescribed special medications aimed at preventing unwanted complications. With the suppression of immunological reactions in a person, anti-infective immunity sharply decreases, or rather, it is completely absent. Weakened immune activity undoubtedly helps foreign cells adapt, but leaves the patient’s body completely without protection.

The first 1–2 months of life after a bone marrow transplant takes place in the hospital. And, even after leaving the medical institution upon discharge, the patient cannot travel a significant distance (for example, go to another city). He should be able to go to the clinic at any time for emergency assistance at the slightest suspicion of the development of complications.

After a bone marrow transplant, a working patient cannot even dream of visiting his favorite team in the next 6 months, just like walking in public places or going shopping, because At every step he will face the danger of encountering an infection.

The patient must remain under the watchful eye of doctors for about a year, undergo tests and examinations. The patient will receive permission to experience the fullness of life only when doctors believe that the foreign tissue has successfully “fused” with the patient’s body and began to perform all the functions of the lost bone marrow.

The survival rate of patients who were lucky in finding and selecting foreign hematopoietic tissue also depends on other circumstances:

• Age (children and young people under 30 benefit, and children can even count on a full recovery);
• The nature of the course and duration of the disease before the procedure (it is advisable to have it within 2 years);
• Gender (in women, graft-versus-host disease develops less frequently).

In general, survival beyond 6-8 years ranges from 40 to 80%. In the absence of reactions from the graft and recipient, that is, with good engraftment of the transplanted tissue, yesterday's patient can start a new life, not limited to any particular age.

Most patients, according to their own reviews, remain satisfied with the transplant and cannot believe that everything is already behind them. Meanwhile, emotional tension may not go away for a long time; a person constantly thinks that the terrible illness will return and then nothing will help him... In such cases, you should contact a psychotherapist, who can definitely instill faith in a bright future without illness.

Organizational and cost issues

Today, the global database consists of 25 million HLA-typed donors. Among Western European countries, Germany confidently holds the lead; their register numbers about 7 million people. In the post-Soviet space, Belarus is the leader, as the republic most affected by the Chernobyl accident. There, already 3 years after the Chernobyl events, tissue typing laboratories were opened and actively working in Gomel and Mogilev. Currently, such laboratories operate in all regional centers, and the total number of potential bone marrow donors is approaching 30 thousand people. Large in territory and population, Russia noticeably lags behind our small neighbor - the Russian register is about 10 thousand people.

But in terms of equipment, clinics in the Russian Federation are in no way inferior to foreign institutions of this type. Doctors involved in transplantology in Russia are rightfully proud of their clinics:

• Institute of Pediatric Hematology and Transplantology named after. R. M. Gorbacheva (St. Petersburg);
• Russian Children's Clinical Hospital (Moscow);
• Hematological Center of the Ministry of Health of the Russian Federation (Moscow).

However The main difficulties of BM transplantology in Russia are not so much the lack of the required number of specialized medical institutions as the small number of the registry. The costs of maintaining laboratories are quite impressive; most government agencies are not able to solve the problem; they are not involved in creating a data bank and searching for typed donors outside of Russia.

It should be noted that the cost of the operation is quite high; in Moscow, for example, the smallest amount you can count on is 1 million rubles, and in the northern capital it is even more - about 2 million rubles. A transplant abroad will cost a pretty penny: in Germany, for example, a donor will be selected, the bone marrow will be transplanted, and postoperative treatment will be provided, but it will cost about 100 thousand euros. In Belarus, the cost of bone marrow transplantation for adults, in principle, differs little from that in Western Europe. Few people can count on a free operation (budget is limited, own register is small).

Video: mini-lecture on bone marrow transplantation

The author selectively answers adequate questions from readers within his competence and only within the OnkoLib.ru resource. Face-to-face consultations and assistance in organizing treatment are not provided at this time.